Rule 1430 & Rule 1155 in California: Metal Grinding, Particulate Matter & Air Quality Compliance Guide
Is Your California Facility Ready for Rule 1430 & Rule 1155 Compliance?
Metal forging, grinding, cutting, machining and other industrial operations can generate particulate matter (PM), metal dust, toxic air contaminants and visible emissions.
For facilities operating within the South Coast Air Quality Management District (South Coast AQMD), two important rules can become especially relevant:
Rule 1430 — Control of Emissions from Metal Grinding Operations at Metal Forging Facilities
and
Rule 1155 — Particulate Matter (PM) Control Devices
Rule 1430 focuses specifically on metal grinding and cutting operations at metal forging facilities, while Rule 1155 establishes requirements for permitted PM control devices, including baghouses, HEPA systems, bin vents, dust collectors, cyclones, electrostatic precipitators and wet scrubbers.
For companies operating these processes, compliance isn’t simply about installing pollution-control equipment.
It is about capturing emissions, maintaining control equipment, monitoring performance, conducting required observations/testing and maintaining defensible records.
What Is South Coast AQMD Rule 1430?
Rule 1430 was adopted on March 3, 2017, to reduce:
Toxic emissions
Particulate matter emissions
Metal dust
Odors
from metal grinding and metal cutting operations at metal forging facilities.
The rule applies to persons who own or operate a metal forging facility where metal grinding or metal cutting operations are conducted.
Certain activities are excluded, including grinding/cutting performed under a continuous flood of metal-removal fluid and certain grinding activities used for equipment maintenance or repair.
Why Was Rule 1430 Created?
South Coast AQMD developed Rule 1430 after investigations into metal-forging operations identified metal grinding as a potentially significant source of metal particulate emissions, including toxic air contaminants.
The rulemaking included:
Site visits
Air-quality sampling
Emission-control evaluations
Industry research
Review of voluntary emission-reduction measures
South Coast AQMD subsequently adopted Rule 1430 to control emissions from metal grinding and cutting at forging facilities.
The objective is simple:
Capture the emissions before they become a community and compliance problem.
What Does Rule 1430 Cover?
Depending on the operation, Rule 1430 can affect facilities conducting:
Hand grinding
Stand grinding
Swing grinding
Billet grinding
Metal cutting
Torch cutting
Other applicable grinding operations
The rule addresses emission collection systems, control devices, housekeeping and operating practices.
Rule 1430 and Emission Control Systems
A key element of Rule 1430 is controlling emissions generated during grinding and cutting.
Applicable operations must be appropriately captured and vented to emission-control equipment.
The rule also establishes requirements concerning capture velocity and positioning of grinding activity relative to the collection hood.
Why does this matter?
Even an excellent baghouse cannot effectively control emissions if the contaminated air is not properly captured.
The compliance chain is:
Grinding Process
↓
Local Hood / Capture
↓
Ductwork
↓
PM Control Device
↓
Filtered Exhaust
↓
Compliant Operation
A weakness at any point can reduce overall control performance.
Rule 1430: Keep Grinding Operations Within the Capture Zone
Rule 1430 requires permanent visual indicators/markings at applicable grinding and cutting stations to identify the maximum distance from the emission-control device at which grinding may occur.
The rule also requires applicable grinding activity to occur in front of the hood face and within the identified capture area, while airflow between the operation and hood must not be obstructed.
In practical terms:
The hood needs to capture the dust where it is generated.
Simply having a hood somewhere near the grinding machine does not guarantee effective capture.
What Is Rule 1155?
South Coast AQMD Rule 1155 — Particulate Matter (PM) Control Devices establishes requirements for permitted PM air-pollution-control devices serving processes with direct, non-combustion PM emissions.
Covered control equipment can include:
Baghouses
HEPA systems
Bin vents
Fabric filters
Dust collectors
Cyclones
Electrostatic precipitators
Wet scrubbers
Rule 1155: Why Your Baghouse Matters
For many industrial facilities, the baghouse is the final line of defense between the process and the atmosphere.
A baghouse problem can result in:
Visible emissions
Increased PM emissions
Filter damage
Bag leakage
Control-device alarms
Production interruptions
Corrective maintenance
Potential compliance problems
Rule 1155 therefore establishes requirements for operation, maintenance, monitoring and recordkeeping.
Rule 1155 PM Control Device Requirements
Rule 1155 requires permitted PM control devices to be operated and maintained according to the manufacturer’s instructions or equivalent written procedures.
The rule also prohibits visible emissions from applicable permitted PM control devices, excluding condensed water vapor.
This creates an important operational principle:
Don’t wait for a source test to discover that your control device isn’t performing properly.
Routine monitoring can identify problems much earlier.
Tier 1, Tier 2 & Tier 3 Baghouses
Rule 1155 divides baghouses into three categories based on filter surface area:
Tier 1
≤ 500 square feet
Tier 2
>500 to 7,500 square feet
Tier 3
>7,500 square feet
The applicable requirements vary depending on the type and size of the PM control device.
Rule 1155 and Visible Emissions Monitoring
Rule 1155 requires trained personnel to perform visible-emissions observations using EPA Method 22 for applicable PM control devices.
The standard frequency is generally a five-minute Method 22 observation once per week, with specific provisions and exemptions in the rule.
If visible emissions are observed, corrective action must be taken and the equipment rechecked to verify that the problem has been corrected.
This is why trained personnel matter.
A poorly performed observation can create uncertainty in your compliance records.
Baghouse Leak Detection Systems — BLDS
For applicable Tier 3 baghouses, Rule 1155 requires a Baghouse Leak Detection System (BLDS).
A BLDS monitors changes associated with particulate loading and can provide an alarm when elevated emissions or baghouse problems are detected.
Facilities must:
Install the required system
Operate it correctly
Calibrate it
Maintain it
Investigate alarms
Document corrective actions
Why BLDS Is Important
Imagine a filter begins developing a leak.
Without effective monitoring, the problem may continue until:
Visible emissions appear
A routine inspection identifies it
A source test detects an issue
An inspector identifies the problem
A functioning BLDS can provide an earlier warning.
That gives facility personnel an opportunity to investigate and correct the issue before emissions become a larger compliance concern.
Rule 1155 Source Testing
Rule 1155 specifies SCAQMD Methods 5.1, 5.2 or 5.3, as applicable, for source tests used to demonstrate compliance with the applicable Tier 3 PM concentration requirement.
For Title V facilities subject to the applicable requirement, the rule provides for an initial source test and subsequent testing every five years. Source tests must be conducted by a laboratory approved through the SCAQMD Laboratory Approval Program.
This makes source-test planning extremely important.
Before scheduling testing, facilities should verify:
Applicable rule requirements
Applicable permit conditions
Correct test method
Sampling location
Operating conditions
Test protocol requirements
Laboratory qualifications
Reporting requirements
Rule 1155 Recordkeeping
Compliance is not only about what happens inside the facility.
Documentation matters.
South Coast AQMD provides Rule 1155 forms for:
PM control-device information
Visible-emission records
BLDS records
Records can include:
Facility information
Observer information
Observation date/time
Process unit
Observation duration
Visible-emission findings
Corrective actions
BLDS inspections
Alarm information
Alarm duration
Cause of alarm
Corrective action
Operating hours
Rule 1155 requires applicable records to be maintained for at least five years and made available to the Executive Officer upon request.
2026 California Air-Quality Update
What Is Happening in 2026?
South Coast AQMD’s 2026 regulatory program continues to emphasize particulate-matter reduction and community exposure reduction.
The agency’s 2026 rule activity overview identifies PM-reduction activities intended to strengthen requirements for operations such as aggregate facilities and reduce particulate matter affecting surrounding communities.
In September 2026, South Coast AQMD also advanced proposed amendments to Rule 1157, addressing PM10 emissions from aggregate and related operations.
Important distinction:
There is not a new 2026 amendment to Rule 1430 or Rule 1155 identified in the current South Coast AQMD sources reviewed for this article.
However, the broader 2026 PM-control environment makes it sensible for facilities to review their existing PM capture, control, monitoring and recordkeeping programs rather than assuming older procedures are sufficient.
South Coast AQMD’s official rule book currently lists Rule 1430 as adopted March 3, 2017 and Rule 1155 as amended May 2, 2014.
Pros of Rule 1430 & Rule 1155 Compliance
✅ 1. Better PM Control
Proper capture and filtration can significantly reduce particulate emissions from industrial processes.
✅ 2. Reduced Toxic Metal Exposure
For metal-processing operations, controlling metal-containing particulate matter can reduce potential exposure.
✅ 3. Improved Equipment Performance
Routine inspections can identify filter, ductwork and baghouse problems before they become major failures.
✅ 4. Early Problem Detection
BLDS and visible-emission monitoring can provide early warning of control-device problems.
✅ 5. Better Compliance Documentation
Well-maintained records demonstrate that the facility is actively managing its control systems.
✅ 6. Stronger Environmental Performance
Effective PM control can contribute to cleaner air around industrial communities.
Cons & Compliance Challenges
❌ 1. Testing Costs
Source testing requires specialized personnel, equipment and laboratories.
❌ 2. Monitoring Requirements
Facilities may need regular Method 22 observations and BLDS monitoring.
❌ 3. Maintenance Expenses
Filters, bags, ducts, fans and control systems require routine maintenance.
❌ 4. Production Disruption
Corrective maintenance or testing may require coordination with production schedules.
❌ 5. Recordkeeping Work
Every observation, alarm, inspection and corrective action needs appropriate documentation.
❌ 6. Equipment Upgrades
Older collection systems may require upgrades to maintain effective capture and filtration.
Common Rule 1430 Mistakes
❌ Grinding Outside the Capture Area
A hood may exist, but the grinding operation may be positioned too far away for effective capture.
❌ Obstructing Airflow
Materials, equipment or other objects can interfere with capture.
❌ Poor Hood Positioning
Incorrect hood placement can reduce capture efficiency.
❌ Ignoring Fugitive Dust
Controlling the exhaust stack does not eliminate all potential fugitive emissions.
❌ Weak Housekeeping
Accumulated metal dust can become an additional environmental and operational concern.
❌ Delayed Maintenance
Waiting until a baghouse or collection system fails can create unnecessary operational and compliance risks.
Common Rule 1155 Mistakes
❌ Skipping Visible-Emission Observations
Applicable Method 22 observations need to be performed and documented.
❌ Ignoring BLDS Alarms
An alarm should trigger investigation and corrective action where required.
❌ Poor Recordkeeping
Missing dates, times, observers, findings or corrective actions can weaken compliance documentation.
❌ Using Unqualified Testing Resources
Applicable source tests must meet the rule’s requirements, including laboratory approval provisions.
❌ Testing Under the Wrong Conditions
Source testing should represent the operating conditions required by the applicable rule and permit.
❌ Ignoring Manufacturer Maintenance Requirements
Control devices need proper operation and maintenance—not just periodic testing.
How EES Helps With Rule 1430 & Rule 1155 Compliance
Rule 1420, 1420.1 & 1420.2 in California: Lead Emissions Testing, Source Testing & 2026 Compliance Guide
Is Your Facility Ready for California’s Lead Emission Compliance Requirements?
If your facility processes lead-containing materials, recycles lead-acid batteries, or operates metal-melting equipment, environmental compliance should be a top priority.
In the South Coast Air Quality Management District (South Coast AQMD), three important lead-emission rules address different categories of facilities:
Rule 1420 – Emission Standard for Lead
Rule 1420.1 – Emission Standards for Lead and Other Toxic Air Contaminants from Large Lead-Acid Battery Recycling Facilities
Rule 1420.2 – Emission Standards for Lead from Metal Melting Facilities
These rules address lead emissions through combinations of emission limits, ambient air monitoring, source testing, control systems, housekeeping, recordkeeping, compliance plans and operational requirements.
And 2026 brings an important reason to review your compliance program.
South Coast AQMD’s 2026 rulemaking forecast identifies potential amendments to all three rules. The proposed work includes arsenic-related requirements, updated testing methods, source-test protocol clarifications, monitoring, storage/handling and post-closure provisions.
For affected facilities, this means that relying on an old compliance checklist may not be enough.
What Are Rules 1420, 1420.1 and 1420.2?
Although these rules are closely related, they do not regulate exactly the same facilities.
Understanding which rule applies to your operation is the first step toward an effective compliance program.
Rule 1420 – Emission Standard for Lead
Rule 1420 is the broader lead-emission rule for facilities that use or process lead-containing materials and are not regulated under the more specific Rules 1420.1 or 1420.2.
The rule’s purpose is to reduce lead emissions and protect public health.
Potentially affected operations can include:
Lead-processing facilities
Lead-containing material processors
Foundries
Certain metal-processing operations
Lead-acid battery-related operations not covered by Rule 1420.1
Other facilities processing lead-containing materials
South Coast AQMD’s current rule structure identifies Rule 1420 separately from the specialized rules for large lead-acid battery recyclers and large metal-melting facilities.
Rule 1420.1 – Large Lead-Acid Battery Recycling Facilities
Rule 1420.1 specifically addresses large lead-acid battery recycling facilities.
South Coast AQMD states that the rule applies to large lead-acid battery recycling facilities that have processed more than 50,000 tons of lead per year under the applicable historical/current applicability provisions.
The rule addresses not only lead but also other toxic air contaminants associated with these operations.
Requirements can include:
Lead emission limits
Arsenic emission requirements
Benzene controls/limits
1,3-butadiene requirements
Ambient air monitoring
Stack/source testing
Housekeeping
Work practices
Monitoring and recordkeeping
Public notification requirements
Control-system requirements
South Coast AQMD describes Rule 1420.1 as having some of the most stringent requirements for lead-acid battery recycling facilities in the country.
Rule 1420.2 – Lead from Metal Melting Facilities
Rule 1420.2 focuses on metal melting facilities that melt 100 tons or more of lead per year.
The rule was adopted to reduce:
Lead emissions
Ambient lead concentrations
Public exposure to lead
It includes requirements involving:
Point-source emission controls
Ambient air lead concentration limits
Source testing
Ambient air monitoring
Housekeeping
Maintenance
Enclosures
Recordkeeping
Compliance plans when applicable
🚨 Major 2026 Update: All Three Rules Are Under Regulatory Review
This is one of the most important reasons affected businesses should review their compliance programs in 2026.
South Coast AQMD’s 2026 rulemaking forecast identifies:
Rule 1420
Potential amendments to address:
Arsenic emissions
Storage and handling requirements
Closure requirements
The objective is to close a regulatory gap between Rule 1420 and Rule 1407, which regulates arsenic, cadmium and nickel from non-ferrous metal melting operations.
Rule 1420.1
Potential amendments are planned to:
Update applicable test methods
Clarify source-test protocol submittal
Potentially address monitoring
Potentially address post-closure requirements
Rule 1420.2
Potential amendments are planned to:
Address arsenic emissions
Close a regulatory gap between Rule 1420.2 and Rule 1407
Potentially address monitoring
Potentially address post-closure requirements
Important:
These items are rulemaking plans/proposed activities—not automatically final requirements. Facilities should verify the adopted rule language and permit conditions before making compliance decisions.
Why Lead Emission Testing Matters
Lead is a toxic air contaminant, and controlling emissions is an important component of protecting workers and surrounding communities.
For regulated facilities, emissions testing can provide evidence that:
Testing can also help identify problems before they become more expensive compliance issues.
What Does Lead Source Testing Involve?
Depending on the applicable rule, equipment and approved test method, testing may evaluate:
Lead Emissions
Measurement of lead concentrations or emission rates from applicable exhaust points.
Particulate Matter
Lead can be associated with particulate emissions, making particulate control important in many processes.
Control Device Performance
Testing may help determine whether equipment such as baghouses, scrubbers or other controls is operating effectively.
Capture Efficiency
For applicable sources, testing can evaluate whether emissions are adequately captured.
Operating Parameters
Testing should be performed under representative conditions required by the applicable rule/test protocol.
Ambient Air Monitoring
One of the major components of the lead rules is ambient air monitoring.
Instead of looking only at what leaves a stack, ambient monitoring can evaluate lead concentrations around the facility.
This provides a different compliance perspective:
Stack Testing
What is being emitted from the source?
Ambient Monitoring
What concentration is present in the surrounding air?
Both can be important for facilities subject to applicable requirements.
Rule 1420.2, for example, includes ambient air monitoring and concentration requirements as part of its compliance framework.
Point-Source Controls
Facilities subject to the lead rules may need appropriate controls on emission points.
Depending on the process, controls may include:
Baghouse systems
Fabric filters
Scrubbers
Enclosures
Local exhaust ventilation
Negative-pressure systems
Other approved control technologies
Rule 1420.1, for example, requires large lead-acid battery recycling facilities to maintain building operations under constant negative pressure so emissions can be collected and routed to air-pollution-control equipment.
Baghouse Monitoring Is Critical
For facilities using baghouses or similar particulate-control equipment, monitoring performance is an important component of compliance.
South Coast AQMD’s Rule 1420 materials include requirements concerning:
Pressure-drop monitoring
Calibration
Data acquisition
Recordkeeping
Bag-leak detection
Maintenance
Why this matters:
A source can pass an emissions test but still experience control-system deterioration later.
Continuous or periodic monitoring can provide an early warning.
Rule 1420 Compliance Plans
For certain facilities, a Compliance Plan can be an important part of the regulatory process.
South Coast AQMD’s Rule 1420 framework includes compliance-plan provisions for qualifying lead-processing facilities, including facilities processing more than specified quantities of lead.
A compliance plan can involve information such as:
Material processed
Lead content
Emission sources
Emission estimates
Monitoring
Air-dispersion modeling
Control measures
Compliance strategies
The exact requirement depends on facility applicability and current rule language.
Air Dispersion Modeling
For certain Rule 1420 facilities, air-dispersion modeling can be part of the compliance process.
Modeling helps estimate how emissions from a facility may affect ambient concentrations.
A professional compliance program can therefore involve:
Emission Testing + Ambient Monitoring + Modeling + Control Evaluation
rather than relying on one test alone.
Housekeeping Is Not Optional
Lead dust can become a significant compliance concern.
Rules 1420, 1420.1 and 1420.2 contain requirements addressing housekeeping, maintenance and control of fugitive lead emissions.
Potential areas of concern include:
Floors
Work areas
Material storage
Process areas
Equipment
Conveyors
Dust collection systems
Maintenance activities
Construction/repair work
Rule 1420.2 specifically addresses fugitive lead-dust potential from certain construction and maintenance activities.
The lesson:
Clean facility ≠ automatically compliant.
But poor housekeeping can create additional emissions and regulatory risk.
Rule 1420.1: More Than Lead
Large lead-acid battery recycling facilities should pay attention to more than lead.
Rule 1420.1 also addresses toxic air contaminants including:
Arsenic
Benzene
1,3-Butadiene
South Coast AQMD’s rule activity page identifies additional administrative, monitoring and source-testing requirements associated with these contaminants.
This makes Rule 1420.1 compliance significantly more complex than a simple lead stack test.
Rule 1420.2: Metal Melting Facilities
If your facility melts significant quantities of lead-containing material, Rule 1420.2 deserves special attention.
Potentially affected industries can include:
Metal recyclers
Foundries
Metal manufacturers
Aerospace-related manufacturing
Steel/metal facilities
Lead-acid battery manufacturing
Other lead-melting operations
The original rulemaking documentation identified metal-melting facilities as significant stationary lead-emission sources and established requirements for ambient monitoring, source testing, point-source controls and housekeeping.
2026 Arsenic Regulatory Development
A particularly important development is the planned effort to address arsenic emissions under Rules 1420 and 1420.2.
South Coast AQMD’s 2026 forecast states that proposed amendments would help close a regulatory gap between these rules and Rule 1407 – Control of Emissions of Arsenic, Cadmium, and Nickel from Non-Ferrous Metal Melting Operations.
Why should businesses care?
A facility that has historically focused primarily on lead compliance may need to evaluate whether arsenic requirements could affect:
Testing
Monitoring
Control equipment
Recordkeeping
Permit conditions
Future facility modifications
2026 Source-Test Protocol Update for Rule 1420.1
For large lead-acid battery recyclers, South Coast AQMD specifically identifies potential updates to applicable test methods and clarification of source-test protocol submittal requirements in the 2026 rulemaking forecast.
This is a strong reason to review your testing program before scheduling the next source test.
Don’t simply reuse an old protocol.
Your compliance team should confirm:
Current rule language
Current test methods
Current protocol requirements
Current permit conditions
Current monitoring requirements
Current reporting requirements
Pros of Rule 1420/1420.1/1420.2 Compliance
✅ 1. Better Lead Emission Control
The rules are designed to reduce lead emissions and ambient exposure.
✅ 2. Improved Community Protection
Ambient monitoring and emission controls provide additional protection for surrounding communities.
✅ 3. Early Detection of Problems
Source testing and monitoring can identify deteriorating control-system performance.
✅ 4. Better Regulatory Documentation
Well-organized test reports and monitoring records provide evidence of compliance.
✅ 5. Improved Facility Management
Regular testing can help facilities understand how process changes affect emissions.
✅ 6. Proactive 2026 Planning
Reviewing the rules now gives facilities time to prepare for potential regulatory changes.
Cons & Challenges
❌ 1. Testing Costs
Lead and toxic-air-contaminant testing requires specialized equipment, laboratories and experienced professionals.
❌ 2. Production Coordination
Testing often needs to occur under specific operating conditions.
❌ 3. Control-System Maintenance
Facilities may need ongoing maintenance of baghouses, scrubbers, ventilation and other controls.
❌ 4. Ambient Monitoring Costs
Applicable facilities may need monitoring networks and ongoing data management.
❌ 5. Recordkeeping Burden
Monitoring, testing and maintenance records must be properly maintained.
❌ 6. Potential Capital Investment
Facilities may need control-system upgrades when existing equipment cannot meet applicable requirements.
❌ 7. Regulatory Changes
The 2026 rulemaking activity means businesses should monitor future amendments rather than relying on outdated compliance procedures.
Common Lead-Compliance Mistakes
❌ Mistake #1: Assuming Rule 1420 Applies to Everyone
Rules 1420.1 and 1420.2 address specific facility categories.
❌ Mistake #2: Treating the Three Rules as Identical
They have different applicability, requirements and compliance pathways.
❌ Mistake #3: Using an Old Source-Test Protocol
Rule 1420.1 is specifically identified for potential 2026 test-method and protocol-submittal updates.
❌ Mistake #4: Ignoring Ambient Monitoring
Stack emissions and ambient concentrations are different compliance questions.
❌ Mistake #5: Ignoring Arsenic
The 2026 rulemaking activity specifically highlights arsenic under Rules 1420 and 1420.2.
❌ Mistake #6: Poor Control-Device Records
A baghouse or scrubber needs documented monitoring and maintenance.
❌ Mistake #7: Waiting Until an Inspection
A proactive compliance review gives you more time to correct problems.
How EES Helps Industries With Rule 1420, 1420.1 & 1420.2
Energy Environmental Solutions, Inc. (EES) can help facilities develop a structured emissions-testing and compliance strategy.
1. Rule Applicability Review
EES can help determine whether your operation falls under:
Rule 1420
Rule 1420.1
Rule 1420.2
or another applicable South Coast AQMD requirement.
2. Lead Emissions Source Testing
EES can support applicable testing programs for:
Lead
Particulate-related emissions
Applicable toxic air contaminants
Control-device performance
3. Source-Test Protocol Development
EES can help prepare source-test protocols covering:
Applicable rule
Emission limits
Test methods
Sampling locations
Operating conditions
QA/QC
Analytical requirements
Calculations
Reporting
4. Ambient Air Monitoring Support
For facilities subject to applicable ambient-monitoring requirements, EES can assist with monitoring program planning and compliance documentation.
5. Control-System Evaluation
EES can help evaluate emission-control systems such as:
Baghouses
Scrubbers
Local exhaust systems
Enclosures
Negative-pressure systems
Other pollution-control equipment
6. Compliance Documentation
EES can help organize:
Source-test reports
Monitoring records
Maintenance records
Compliance documentation
Corrective-action records
7. 2026 Regulatory Readiness
With Rules 1420, 1420.1 and 1420.2 identified for potential 2026 amendments, EES can help facilities review their existing compliance program against developing requirements.
If your facility processes lead-containing materials or operates lead-melting/recycling equipment, reviewing your compliance program before your next test can help identify gaps while there is still time to address them.
🚨 Is Your Facility Ready for the 2026 Lead Compliance Requirements?
EES Can Help With:
✔ Rule 1420 Applicability Review
✔ Rule 1420.1 Compliance Support
✔ Rule 1420.2 Compliance Support
✔ Lead Emissions Testing
✔ Source-Test Protocol Development
✔ Ambient Air Monitoring Support
✔ Control-System Evaluation
✔ Toxic Air Contaminant Testing
✔ Compliance Reporting
✔ Retesting & Corrective-Action Support
Request a Lead Emissions Compliance Review
Know Your Emissions. Verify Your Controls. Prepare for Regulatory Changes.
If you operate a lead-processing, battery-recycling or metal-melting facility, contact EES for a professional compliance review.
Send EES:
📍 Facility Location ⚙️ Process Type 🧪 Materials Processed 🔥 Furnace/Process Information 💨 Control Equipment Details 📄 Current Air Permit 📊 Previous Source-Test Report
Is Your Chromium Plating or Chromic Acid Anodizing Facility Ready for Rule 1469 Compliance in 2026?
If your facility performs chromium electroplating or chromic acid anodizing in the South Coast Air Quality Management District (South Coast AQMD), Rule 1469 should be a critical part of your environmental compliance program.
South Coast AQMD Rule 1469 – Hexavalent Chromium Emissions from Chromium Electroplating and Chromic Acid Anodizing Operations is designed to reduce emissions of hexavalent chromium from affected facilities. The rule applies to facilities performing chromium electroplating or chromic acid anodizing and establishes requirements for emission controls, building enclosures, source testing, monitoring, housekeeping, recordkeeping and reporting.
And there is an important 2026 development:
Rule 1469 was amended on December 5, 2025, and new requirements for functional chrome-plating facilities became effective beginning January 1, 2026.
For facilities that have not reviewed their Rule 1469 compliance strategy recently, now is the time to check your tanks, controls, permits, source-test schedule and monitoring records.
Certain associated process tanks and control equipment
The current rule defines Functional Chrome Plating as including hard chromium electroplating, chromic acid anodizing and continuous passivation.
Rule 1469 is a South Coast AQMD rule, so it should not be presented as a universal statewide California requirement. Facilities outside South Coast AQMD may have different requirements from their local air district and applicable California regulations.
Why Is Hexavalent Chromium Compliance Important?
Hexavalent chromium, commonly written as Cr(VI) or Cr+6, can be generated as a mist or emission during certain chromium plating and anodizing operations.
Rule 1469 therefore focuses on controlling emissions at the source.
The compliance strategy can involve:
Tank Controls
→ Emission Capture
→ Air Pollution Control
→ Source Testing
→ Parameter Monitoring
→ Maintenance
→ Recordkeeping
→ Annual Compliance Reporting
This makes Rule 1469 considerably more than a one-time emissions test.
🚨 Major 2026 Rule 1469 Update
One of the most important developments for 2026 is the implementation of stricter requirements for functional chrome-plating facilities.
South Coast AQMD’s 2025 regulatory advisory stated that, beginning January 1, 2026, functional plating facilities would face:
Lower emission limits for applicable Tier III tanks
More frequent source testing
Additional requirements for pollution-control systems
The advisory identified a 0.00075 mg/amp-hr emission limit for functional chrome-plating tanks measured downstream of the add-on air-pollution-control device.
The amended Rule 1469 now incorporates these requirements for functional chrome facilities.
Why this matters
A facility that passed an older source test may not automatically be ready for the newer 2026 requirements.
Your previous test report, control device, permit conditions and testing frequency should be reviewed against the current requirements.
Rule 1469 Was Amended December 5, 2025
South Coast AQMD’s official rule book currently identifies Rule 1469 as amended:
October 9, 1998
May 2, 2003
December 5, 2008
November 2, 2018
April 2, 2021
December 5, 2025
The December 5, 2025 amendment is particularly important because it incorporates more stringent requirements associated with California’s Chrome Airborne Toxic Control Measure and establishes additional provisions for functional chrome operations and phase-out of hexavalent chromium use.
What Changed for Functional Chrome Facilities?
Beginning January 1, 2026, applicable functional chrome-plating facilities must meet the requirements in the amended rule.
For affected Tier III tanks, the rule establishes different emission limits depending on the tank and control-device configuration.
Examples include:
0.00075 mg/amp-hr
For a Tier III tank connected to an add-on air-pollution-control device that also controls a functional chrome-plating tank.
0.20 mg/hr
For certain Tier III tanks connected to an applicable add-on control device with a maximum exhaust rate of 5,000 cfm or less, or certain non-ventilated control configurations.
0.004 mg/hr-ft²
For certain Tier II/Tier III tanks connected to an add-on air-pollution-control device with an exhaust rate greater than 5,000 cfm and not connected to a functional chrome-plating tank.
The applicable limit must be determined from the facility’s exact configuration and current rule/permit conditions.
New Source-Testing Expectations
Source testing is one of the most important components of Rule 1469 compliance.
The amended rule requires applicable facilities to conduct source testing according to the specified schedule and approved source-test procedures.
For functional chrome facilities, the requirements are more frequent than the older general schedule.
South Coast AQMD’s 2025 regulatory advisory stated that source tests were required in 2024 or 2025 to demonstrate compliance with the January 1, 2026 requirements, followed by source testing every two calendar years.
In practical terms:
2026 compliance is not simply “we tested last year.”
You need to determine:
What tank?
What tier?
What process?
What control device?
What emission limit?
When was the last passing test?
When is the next test due?
Rule 1469 Source-Test Protocol
Source testing should be planned well before the actual field test.
The rule requires applicable source tests to be conducted according to an approved source-test protocol.
The protocol addresses items such as:
Test criteria
Target chromium concentration
Analytical information
Sampling parameters
Operating conditions
Test methods
Applicable emission limits
Required calculations
South Coast AQMD also requires advance notification of scheduled source testing. Under the current rule, the owner/operator must notify the Executive Officer at least 60 calendar days before the scheduled source test.
Don’t make this mistake:
Scheduling the test first and worrying about the protocol afterward.
A professional compliance program should start with the regulatory review and test protocol.
What Is Measured During Rule 1469 Testing?
Depending on the applicable source and testing requirement, Rule 1469 testing can involve measurement and evaluation of:
Hexavalent Chromium
The primary toxic pollutant addressed by the rule.
Total Chromium
Certain approved methods can report chromium emissions as total chromium where permitted by the applicable requirements.
Capture Efficiency
Testing may be necessary to demonstrate that chromium emissions are properly captured by the air-pollution-control system.
Control-Device Performance
Pressure, airflow and other operating parameters can be important to demonstrating proper control-device operation.
South Coast AQMD identifies CARB Method 425, U.S. EPA Method 306 and South Coast AQMD Method 205.1 among approved testing approaches in the rule, depending on the applicable requirement.
Tier I, Tier II and Tier III Tanks
Rule 1469 categorizes certain hexavalent-chromium tanks into Tier I, Tier II and Tier III classifications.
For example, the current rule defines a Tier I tank based in part on operation with a hexavalent chromium concentration of 1,000 ppm or greater.
Tier II and Tier III classifications are determined using specified temperature/concentration ranges and other equipment/process characteristics.
Why classification matters
Your tank classification can affect:
Emission controls
Testing
Monitoring
Operating requirements
Source-test frequency
Compliance limits
Phase-out requirements
A tank-by-tank applicability review is therefore essential.
Air Pollution Control Systems
Rule 1469 can require affected facilities to control chromium emissions using appropriate pollution-control techniques.
Examples include:
Add-on air pollution control devices
Add-on non-ventilated control devices
Composite mesh-pad systems
Packed-bed scrubbers
Fiber-bed mist eliminators
HEPA filtration
Tank covers
Mechanical fume suppressants
Approved chemical fume suppressants
The rule also establishes operating-parameter monitoring requirements for applicable control systems.
Control-Device Monitoring Matters
Passing a source test does not mean the facility can stop monitoring.
Rule 1469 establishes monitoring requirements for parameters such as:
Static pressure
Differential pressure
Airflow
Collection-slot velocity
Push-air manifold pressure
For certain control systems, measurements are required at specified intervals and must remain within applicable ranges.
The rule also includes specific corrective-action requirements when measurements fall into repairable or failing ranges.
Example: Collection-Slot Monitoring
For certain add-on control systems, Rule 1469 establishes categories such as:
Acceptable
Measurements above specified thresholds based on the most recent passing source test or screening.
Repairable
Measurements falling into specified intermediate ranges may require repair or replacement and re-measurement.
Failing
Measurements below specified thresholds can require immediate action, including shutdown of tanks controlled by the affected system.
Why this matters for your business
Your environmental compliance team needs to know what happens when a monitoring value moves outside the acceptable range.
Waiting until an annual test can be too late.
Housekeeping & Fugitive-Emission Controls
Rule 1469 is not only about stack emissions.
The rule also addresses potential fugitive chromium emissions through requirements involving:
Building enclosures
Tank process areas
Cleaning
Dragout control
Containment
Storage
Tank labeling
Handling of contaminated materials
Prevention of visible residue accumulation
For example, the current rule requires certain containment devices used to control dragout to be cleaned weekly so that visible residue, dust or potentially contaminated liquid does not accumulate.
Building Enclosure Requirements
Applicable Tier II and Tier III tanks must operate within required building-enclosure configurations.
Rule 1469 also contains specific provisions concerning enclosure openings and sensitive receptors.
For certain openings facing a sensitive receptor or school within 1,000 feet, additional closure requirements apply.
This makes facility layout and ventilation design an important part of compliance.
Chemical Fume Suppressants
Facilities using wetting-agent chemical fume suppressants must use products certified by South Coast AQMD under the applicable program.
South Coast AQMD states that certified chemical fume suppressants must achieve the applicable emission-performance criterion, and PFOS-containing suppressants are prohibited from being added to anodizing/chrome-plating tanks under the applicable requirements.
Facility operators should verify:
Suppressant certification
Surface tension
Bath chemistry
Monitoring records
Required testing
Applicable restrictions
Training & Certification
Rule 1469 includes training and certification provisions for personnel responsible for specified environmental compliance activities.
The current rule states that designated personnel involved in areas such as environmental compliance recordkeeping, electroplating bath chemistry and surface-tension testing must complete an approved training program and receive the required certification, with certification occurring on a two-year cycle.
This means your compliance program should include people, procedures and equipment—not just emissions testing.
Phase-Out of Hexavalent Chromium
One of the biggest long-term developments is the phase-out framework.
The amended Rule 1469 prohibits construction or operation of new tanks using hexavalent chromium for decorative plating, hard chromium plating or chromic acid anodizing unless the facility already had qualifying hexavalent-chromium equipment permitted on or before January 1, 2024.
Decorative Chrome
The default phase-out date is:
January 2, 2030
subject to the alternative phase-out provisions in the rule.
Functional Chrome
The rule establishes a phase-out date beginning:
January 2, 2039
or the date specified in the applicable California Air Toxics Control Measure, whichever is later, subject to the rule’s provisions.
What does this mean for manufacturers?
Businesses using hexavalent chromium should begin evaluating:
Alternative chemistry + replacement equipment + permits + capital planning + testing + production impacts
rather than waiting until a phase-out deadline approaches.
Rule 1469 Requirements for Modified Facilities
Facilities undergoing modifications face additional requirements.
Under the current rule, facilities modifying applicable equipment after January 1, 2024 must meet specified requirements, including maintaining permitted annual ampere-hour limitations and controlling affected tanks using appropriate add-on or non-ventilated control systems.
For applicable modified tanks, the rule establishes a 0.00075 mg/amp-hr or lower emission limitation demonstrated through source testing.
Planning a facility modification?
Review Rule 1469 before purchasing or installing the equipment.
Environmental compliance should be part of the engineering design—not an afterthought.
Rule 1469 Compliance Pros
✅ 1. Better Control of Hexavalent Chromium
Emission controls and testing help reduce chromium emissions from affected operations.
✅ 2. Improved Process Control
Monitoring airflow, pressure, surface tension and other parameters can identify problems early.
✅ 3. Better Environmental Documentation
Professional source-test reports and monitoring records provide valuable compliance documentation.
✅ 4. Early Detection of Control-System Problems
Testing and monitoring can reveal issues with scrubbers, mist eliminators, ventilation systems and other controls.
✅ 5. Supports Long-Term Transition Planning
The phase-out framework gives businesses an opportunity to evaluate alternative technologies and processes.
Functional chrome facilities face increased source-testing requirements under the newer framework.
❌ 3. Equipment Upgrades
Some facilities may need upgrades to air-pollution-control systems to meet applicable limits.
❌ 4. Operational Disruption
Testing, maintenance and equipment modifications must be coordinated with production.
❌ 5. Detailed Recordkeeping
Compliance involves maintaining testing, monitoring, maintenance and reporting records.
❌ 6. Future Transition Costs
Facilities relying on hexavalent chromium should evaluate future process and equipment replacement costs well ahead of phase-out dates.
Common Rule 1469 Compliance Mistakes
❌ Using an outdated source-test schedule
The 2026 requirements can be more stringent for functional chrome operations.
❌ Testing without reviewing the current rule
A previous successful test does not automatically establish current compliance.
❌ Ignoring the control device
A good emissions result depends on properly functioning capture and control equipment.
❌ Poor monitoring records
Missing pressure, airflow or surface-tension records can weaken your compliance documentation.
❌ Delaying protocol preparation
Applicable source-test protocols need regulatory approval before the field test.
❌ Ignoring facility modifications
A modification can trigger additional requirements.
❌ Waiting for an inspection
A proactive compliance review is generally much easier to manage than an emergency response.
How EES Helps With Rule 1469 Compliance
Energy Environmental Solutions, Inc. (EES) can help chromium-plating, anodizing and metal-finishing facilities with the technical testing and compliance documentation associated with Rule 1469.
1. Rule 1469 Applicability Review
EES can review:
Facility + Tanks + Process + Chromium Type + Tank Tier + Control Device + Permit
to identify applicable testing and monitoring requirements.
2. Hexavalent Chromium Source Testing
EES can provide/support applicable hexavalent chromium emissions testing and source-test programs.
This can include evaluation of:
Chromium emissions
Applicable emission limits
Operating conditions
Sampling parameters
Control-device performance
3. Source-Test Protocol Development
EES can help prepare a detailed source-test protocol covering:
Applicable regulations
Test methods
Sampling procedures
Test conditions
Analytical requirements
QA/QC
Calculations
Reporting requirements
4. Capture Efficiency Testing
EES can support applicable testing to evaluate whether chromium emissions are being properly captured by the ventilation and control system.
5. Control-System Performance Evaluation
EES can help evaluate relevant operating parameters such as:
Airflow
Pressure
Collection velocity
Control-device performance
Applicable monitoring parameters
6. Compliance Reporting
EES can help organize technical documentation and source-test reports for regulatory compliance records.
7. Retesting & Corrective-Action Support
If testing identifies an exceedance or control-system problem, EES can assist with planning follow-up testing and documenting corrective actions.
EES Rule 1469 Compliance Process
REVIEW
Facility + Permit + Tanks + Rule Applicability
↓
CLASSIFY
Tier I / Tier II / Tier III + Process Type
↓
PLAN
Applicable Limit + Test Method + Operating Conditions
↓
PROTOCOL
Prepare & Submit Source-Test Protocol
↓
TEST
Hexavalent Chromium / Chromium + Capture & Control Parameters
Is Your Chromium-Plating Operation Ready for the 2026 Requirements?
Send EES your:
📍 Facility Location ⚙️ Process Type 🧪 Chromium Chemistry 🛢️ Tank Information 💨 Air Pollution Control Device 📄 Current Permit 📊 Previous Source-Test Report
Request a Rule 1469 Compliance Assessment Today.
Test Your Emissions. Verify Your Controls. Strengthen Your Compliance Program.
Rule 1147 Compliance in California: NOx Testing, CO Testing & Source Testing Requirements
Is your combustion equipment ready for South Coast AQMD Rule 1147 compliance?
If your facility operates permitted gas- or liquid-fueled combustion equipment that is not covered by another Regulation XI rule, South Coast AQMD Rule 1147 – NOx Reductions from Miscellaneous Sources may apply to your equipment. The rule is designed to reduce NOx emissions while limiting CO emissions.
For manufacturers, industrial facilities, commercial operations, environmental managers and plant owners, understanding Rule 1147 is important because compliance can involve emission limits, source testing, monitoring, combustion-system maintenance, recordkeeping and permit requirements.
Important: Rule 1147 is a South Coast AQMD rule, not a uniform statewide California requirement.
What Is Rule 1147?
Rule 1147 – NOx Reductions from Miscellaneous Sources applies to manufacturers, distributors, retailers, installers, owners and operators of gaseous- and/or liquid-fueled combustion equipment that requires a South Coast AQMD permit when another Regulation XI rule does not apply.
The current adopted rule was amended May 6, 2022.
Rule 1147 can cover a wide range of equipment, including:
Ovens
Dryers
Heaters
Furnaces
Kilns
Calciners
Cookers
Roasters
Heated tanks
Thermal oxidizers
Catalytic oxidizers
Afterburners
Vapor incinerators
Evaporators
Fryers
Parts washers
Autoclaves
Make-up air heaters
Certain turbines
Other miscellaneous combustion equipment
The exact applicability depends on the equipment, permit status, fuel, heat-input rating and whether another South Coast AQMD rule applies.
Why Rule 1147 Matters to California Industries
NOx emissions contribute to ozone and other air-quality problems. Rule 1147 establishes emission requirements intended to reduce NOx from combustion sources while also establishing CO limits for applicable equipment.
For businesses, compliance is not simply about having a permitted burner.
You need to demonstrate that applicable equipment continues to meet the required emission limits under the applicable compliance pathway.
2026 Rule 1147 Update: What Businesses Need to Know
The major regulatory change remains the May 6, 2022 amendment, which introduced updated NOx and CO limits, implementation schedules, monitoring/source-testing requirements, revised exemptions and provisions affecting both RECLAIM and non-RECLAIM facilities.
South Coast AQMD’s current official rule book lists Rule 1147 as amended May 6, 2022.
South Coast AQMD also provides a Rule 1147 Guidance Document dated March 7, 2025, which explains applicability, implementation schedules and source-testing requirements.
What does this mean in 2026?
Facilities should not rely on an old compliance checklist.
Your team should verify:
Current Rule + Current Permit + Equipment Age + Rated Heat Input + Previous Test Date + Applicable Compliance Schedule
Which Equipment Can Be Affected?
Rule 1147 has a broad equipment scope.
Examples include:
🔥 Industrial Heating Equipment
Furnaces
Heaters
Ovens
Dryers
Kilns
Calciners
Roasters
🏭 Process Equipment
Heated process tanks
Evaporators
Parts washers
Autoclaves
Cookers
🌡️ Air & Pollution-Control Equipment
Make-up air heaters
Thermal oxidizers
Catalytic oxidizers
Afterburners
Vapor incinerators
⚡ Other Combustion Equipment
Certain turbines and miscellaneous gas- or liquid-fired units may also fall within the rule.
Equipment Below 325,000 BTU/hr
One important exemption is that Rule 1147 does not apply to units with a heat-input rating below 325,000 Btu/hr, subject to the rule’s other provisions. Charbroilers and food ovens are also specifically excluded.
This is one reason a facility should perform an equipment-by-equipment applicability review rather than assuming every combustion device is regulated identically.
Rule 1147 NOx & CO Limits
The rule uses different emission limits depending on:
Equipment category
Fuel type
Process temperature
Equipment age/status
Applicable compliance schedule
For example, Table 2 includes requirements such as:
These are reference examples from Table 2, not a substitute for determining the limit applicable to a particular unit.
The “Less Than 1 Pound of NOx Per Day” Option
One of the important Rule 1147 compliance pathways allows an owner/operator to elect to demonstrate that NOx emissions are less than one pound per day averaged over a calendar month, subject to the rule’s requirements.
This can involve a non-resettable totalizing time meter or fuel meter and prescribed operating/fuel-use limits.
For example, the rule provides monthly operating-hour limits based on rated heat input for certain units:
Below 1 MMBtu/hr: 240 hours/month
1 to below 1.5 MMBtu/hr: 160 hours/month
1.5 to 2 MMBtu/hr: 120 hours/month
The actual compliance pathway must be evaluated against the rule and facility conditions.
Rule 1147 Source Testing Requirements
This is where professional emissions testing becomes particularly important.
Rule 1147 requires applicable compliance determinations to use a South Coast AQMD-approved source-test protocol and test under specified operating conditions. Testing generally uses a period of at least 15 minutes and no more than 60 consecutive minutes, unless an alternative period is approved.
Testing must be performed after startup and at the unit’s normal firing rate.
For specified equipment categories, an additional compliance determination may be required at low heat input or during a specified period after startup.
Source-Test Protocol: A Critical Step
Don’t wait until the testing date to think about the protocol.
Rule 1147 requires the source-test protocol to be submitted to the Executive Officer for approval no later than 90 days before the scheduled source test.
Typical process:
Rule Review
↓
Equipment Review
↓
Test Protocol Development
↓
Protocol Submission
↓
Regulatory Approval
↓
Field Testing
↓
Data Analysis
↓
Compliance Report
This is one reason early scheduling is important.
Required Testing Frequency
For applicable units with NOx emissions ≥1 pound/day, Rule 1147 establishes source-testing frequencies based on rated heat input capacity:
Units <10 MMBtu/hr
Every 5 calendar years
Units ≥10 and <40 MMBtu/hr
Every 3 calendar years
Units ≥40 MMBtu/hr
Every calendar year
The rule also establishes minimum intervals between tests and special provisions for units that have been shut down for extended periods.
This makes one thing clear:
Knowing your last test date is not enough.
You need to know the rated heat input and applicable compliance category.
Who Can Conduct Rule 1147 Testing?
Rule 1147 requires applicable compliance determinations to be performed using an independent contractor approved by the Executive Officer under the Laboratory Approval Program for the applicable test methods.
This is an important consideration when selecting a testing company.
Before scheduling your test, verify:
Appropriate test-method approval
Qualified personnel
Proper instrumentation
Calibration procedures
QA/QC
South Coast AQMD experience
Reporting capability
What Is Tested?
Depending on the equipment and compliance pathway, testing can involve:
NOx
The primary pollutant targeted by Rule 1147.
CO
Rule 1147 also establishes CO requirements for applicable equipment.
Oxygen
O₂ measurements are used in applicable emission calculations and correction procedures.
Carbon Dioxide
CO₂ may also be measured as part of applicable source-test procedures.
South Coast AQMD Method 100.1 and Method 10.1 are among the methods identified in Rule 1147 for applicable compliance determinations.
Rule 1147 Maintenance Requirements
Testing alone is not enough.
Rule 1147 requires owners/operators to perform combustion-system maintenance according to the manufacturer’s schedule and specifications and maintain the relevant records.
Rule 1134 Compliance in California: Stationary Gas Turbine NOx Testing, Monitoring & Source Testing Guide
Does your facility operate a stationary gas turbine in Southern California?
If yes, South Coast AQMD Rule 1134 – Emissions of Oxides of Nitrogen from Stationary Gas Turbines may be an important part of your air-quality compliance program.
Rule 1134 establishes NOx emission requirements and monitoring/source-testing provisions for applicable stationary gas turbines. The rule is particularly important for facilities operating larger turbines, turbines with catalytic controls, and turbines located at non-RECLAIM NOx facilities.
South Coast AQMD currently lists Rule 1134 as amended February 4, 2022. It also currently lists a Proposed Amended Rule 1134 in its active rulemaking section, meaning facilities should continue monitoring regulatory developments in 2026.
For facility owners, plant managers and EHS professionals, the message is simple:
Don’t wait for a compliance test to reveal an emissions problem.
Rule 1134 California
What Is Rule 1134?
Rule 1134 – Emissions of Oxides of Nitrogen from Stationary Gas Turbines is a South Coast AQMD source-specific rule intended to control NOx emissions from stationary gas turbines.
It is part of South Coast AQMD’s Regulation XI, which contains source-specific standards. The current rule book identifies Rule 1134 as applying to emissions of oxides of nitrogen from stationary gas turbines and shows its latest adopted amendment as February 4, 2022.
Important:
Rule 1134 is not a statewide California rule.
It applies within the South Coast AQMD jurisdiction when the facility/equipment meets the rule’s applicability provisions.
Facilities elsewhere in California may be subject to requirements established by their local air district.
Why Does Rule 1134 Matter?
NOx is a major air pollutant associated with combustion equipment.
NOx can contribute to:
Ozone formation
Smog
Nitrogen dioxide pollution
Fine particulate formation
Regional air-quality problems
South Coast AQMD developed Rule 1134 specifically to reduce NOx emissions from stationary gas turbines.
For businesses, however, compliance is not simply about operating a turbine.
It is about being able to demonstrate that the turbine is operating within the applicable regulatory and permit requirements.
Which Gas Turbines Can Be Subject to Rule 1134?
The rule contains specific applicability provisions and exemptions.
Historically and under the current rule framework, stationary gas turbines rated at 0.3 MW or greater are an important category.
South Coast AQMD’s compliance guidance states that, beginning January 1, 2024, owners/operators of stationary gas turbines rated 0.3 MW or larger must operate within the applicable Table I NOx emission limits, subject to the rule’s provisions.
Potentially affected equipment can include:
Industrial gas turbines
Cogeneration turbines
Combined-cycle turbines
Power-generation turbines
Turbines at wastewater facilities
Natural-gas-fired turbines
Turbines with SCR systems
Turbines at non-RECLAIM NOx facilities
But don’t assume every turbine has identical requirements.
Applicability depends on factors including:
Turbine size + installation history + facility status + fuel + control technology + operating conditions + permit conditions
2026 Update: What Facilities Should Know About Rule 1134
There are two important points for businesses in 2026.
1. The Current Adopted Rule
South Coast AQMD’s official rule book identifies Rule 1134 as amended February 4, 2022.
The 2022 amendment included changes involving:
NOx requirements
Recuperative gas turbines
Selective catalytic reduction (SCR)
CEMS provisions
Monitoring requirements
Startup/shutdown provisions
Liquid-fuel use during natural-gas curtailments at certain health facilities
South Coast AQMD’s February 2022 Governing Board materials describe these amendments and their purpose.
2. Rule 1134 Is Also Listed in Active Rulemaking
South Coast AQMD’s current Active Proposed Rules page lists Proposed Amended Rule 1134 among rules currently in the proposal/amendment process.
The dedicated Rule 1134 proposal page contains the 2021 amendment-development materials, including draft rule language, staff reports and public-hearing documents.
What does this mean for industry?
A proposed amendment is not automatically an adopted requirement.
Facilities should comply with the currently adopted rule and permit conditions while monitoring the rulemaking process for future changes.
Rule 1134 NOx Emission Limits
Rule 1134 contains NOx limits based on turbine size and applicable technology.
The rule’s reference limits include categories such as:
Stationary Gas Turbine
Reference NOx Limit
0.3 to <2.9 MW
25 ppm
2.9 to <10 MW
9 ppm
2.9 to <10 MW, No SCR
15 ppm
10 MW and larger
9 ppm
10 MW and larger, No SCR
12 ppm
≥60 MW Combined Cycle, No SCR
15 ppm
≥60 MW Combined Cycle
9 ppm
There are additional provisions and special categories, including turbines using qualifying sewage-digester-gas fuel. The applicable compliance calculation can also involve the turbine’s demonstrated or manufacturer-rated efficiency.
Important:
Never determine your compliance obligation from a generic table alone.
The applicable limit can depend on the specific turbine, control technology, permit and rule provisions.
Why NOx Testing Is Important
A gas turbine can appear to operate normally while its NOx emissions change because of:
Combustion conditions
Fuel characteristics
Turbine load
Air/fuel ratio
Burner condition
SCR performance
Catalyst condition
Ammonia injection
Control-system performance
Maintenance condition
Therefore:
Normal operation does not automatically mean compliant emissions.
Professional emissions testing provides objective data.
Rule 1134 Source Testing
For applicable turbines that do not use a CEMS, Rule 1134 includes source-testing requirements.
The rule provides for measurement of parameters including:
NOx concentration
Carbon monoxide concentration
Turbine efficiency, where applicable
NOx and CO concentrations are expressed in ppm by volume and corrected to 15% oxygen on a dry basis, according to the rule’s provisions.
This is where professional source testing becomes critical.
A compliant test requires more than simply taking an emissions reading.
It requires:
Correct sampling location
Correct test method
Proper calibration
Representative operating conditions
Quality assurance
Accurate calculations
Regulatory documentation
CEMS Requirements Under Rule 1134
Large turbines may have additional monitoring obligations.
Under Rule 1134, certain gas turbines 2.9 MW and larger at non-RECLAIM NOx facilities are subject to continuous monitoring provisions.
The rule requires applicable systems to monitor NOx and oxygen and also capture information such as:
Flow rate
Water/steam-to-fuel ratio where applicable
Operating time
Turbine output in MW
The CEMS requirements reference South Coast AQMD Rules 218, 218.1, 218.2 and 218.3.
That means Rule 1134 compliance can connect directly with:
CEMS Certification + QA/QC + RATA + CGA + Data Validation
CEMS vs. Source Testing
CEMS
Source Testing
Continuous monitoring
Periodic testing
Provides ongoing emissions data
Provides test-period emissions data
Used for applicable large turbines
Used where source testing is required
Requires QA/QC
Requires approved test procedures
May require certification
Requires proper field testing
Can identify changes over time
Provides a compliance snapshot
Depending on the turbine and regulatory requirements, a facility may need one or both approaches.
What Happens During a Gas Turbine Emissions Test?
A professional test program may include:
Step 1 — Pre-Test Review
Review:
Air permit
Turbine specifications
Fuel
Control equipment
Previous test results
Applicable Rule 1134 requirements
Step 2 — Test Planning
Determine:
Pollutants
Test methods
Operating conditions
Sampling location
Required test runs
Equipment
QA/QC
Step 3 — Equipment Preparation
Verify:
Calibration
Sampling equipment
Analyzers
Data systems
Gas standards
Flow measurement
Step 4 — Field Testing
Collect representative emissions data under applicable operating conditions.
Step 5 — Data Validation
Review:
Calibration data
Run data
QA/QC
Operating parameters
Calculations
Step 6 — Compliance Evaluation
Compare the results with applicable requirements.
Step 7 — Reporting
Prepare the technical source-test report and required documentation.
Common Rule 1134 Compliance Problems
1. High NOx
Potential causes include:
Combustion problems
Poor tuning
Control-system malfunction
Fuel changes
Catalyst problems
2. SCR Performance Problems
Catalyst degradation or improper ammonia control can affect emissions performance.
3. CEMS Problems
Analyzer drift, calibration issues or sampling-system problems can affect data validity.
4. Incorrect Operating Conditions
Testing at an inappropriate load may produce results that do not represent required compliance conditions.
5. Poor Documentation
Missing calibration, maintenance or testing records can create unnecessary compliance difficulties.
Rule 1134 Compliance Pros
✅ 1. Better NOx Control
Testing and monitoring help identify excessive NOx emissions.
✅ 2. Early Problem Detection
Emission testing can reveal problems before they become larger operational issues.
✅ 3. Improved Combustion Performance
Testing can help facilities understand turbine performance.
✅ 4. Better Compliance Documentation
Professional test reports create useful regulatory records.
✅ 5. Supports Environmental Goals
NOx reductions contribute to improved regional air quality.
✅ 6. Better Maintenance Decisions
Emission trends can provide an additional indicator of equipment condition.
Rule 1134 Compliance Cons / Challenges
❌ Testing Costs
Source testing requires specialized personnel, instruments and laboratory resources.
❌ Operational Coordination
The turbine may need to operate under specified conditions during testing.
❌ CEMS Investment
Large applicable turbines may require continuous monitoring systems.
📍 Facility Location ⚙️ Turbine Manufacturer & Model ⚡ MW Rating 🔥 Fuel Type 🛠️ Control Technology / SCR Information 📄 Current Permit 📊 Previous Test Report
Request a Rule 1134 Compliance Review Today
Test Your Emissions. Verify Your Compliance. Protect Your Operation.
Rule 1110.2 Compliance in California: Stationary Engine Testing, NOx, CO & VOC Requirements
Is your stationary engine compliant with California’s air-quality requirements?
If your facility operates a gaseous- or liquid-fueled stationary engine in the South Coast Air Quality Management District (South Coast AQMD), Rule 1110.2 may apply to your equipment.
The rule is designed to reduce NOx, VOC and CO emissions from regulated engines. The current South Coast AQMD rule was amended on November 3, 2023, and South Coast AQMD currently lists Proposed Amended Rule 1110.2 (PAR 1110.2) among rules in the proposal/amendment process.
For facility owners, plant managers and EHS professionals, this means engine testing, monitoring, recordkeeping and compliance planning should not be treated as an afterthought.
Rule 1110.2 California
What Is South Coast AQMD Rule 1110.2?
Rule 1110.2 – Emissions from Gaseous- and Liquid-Fueled Engines establishes emission and monitoring requirements for applicable engines.
The current rule states that its purpose is to reduce:
NOx — Nitrogen Oxides
VOC — Volatile Organic Compounds
CO — Carbon Monoxide
The rule generally applies to stationary and portable engines over 50 rated brake horsepower (bhp), subject to its applicability provisions and exemptions.
Important California compliance point
Rule 1110.2 is not a single statewide California rule. It is a South Coast AQMD rule, so facilities outside the South Coast AQMD jurisdiction must determine which local air-district requirements apply.
Why Rule 1110.2 Matters to Your Business
Stationary internal-combustion engines are used throughout California industry for:
Power generation
Natural-gas compression
Cogeneration
Industrial processes
Water and wastewater operations
Agricultural operations
Emergency/standby power
Other mechanical and electrical applications
Depending on the engine and operating conditions, emissions can include significant amounts of NOx, CO and VOCs.
That’s why regulatory agencies require facilities to demonstrate that applicable engines are operating within their permitted and regulatory limits.
Which Engines Can Be Subject to Rule 1110.2?
Potentially regulated equipment can include:
Natural Gas Engines
Used for generators, compressors, pumps and industrial equipment.
Biogas Engines
Engines operating on landfill gas or digester gas can have specific requirements.
Liquid-Fueled Engines
Certain stationary engines using liquid fuels may fall under the rule.
Large Industrial Engines
Large engines can trigger more extensive monitoring requirements.
Low-Use Engines
The rule contains specific provisions for engines operating less than 500 hours/year or using less than 1 × 10⁹ Btu/year of fuel, subject to the applicable requirements.
2026 Regulatory Update: Rule 1110.2 Remains Under Amendment Review
One of the most important things facility operators should know in 2026 is that South Coast AQMD currently lists Proposed Amended Rule 1110.2 as an active rulemaking item.
The PAR 1110.2 process was developed alongside proposed Rule 1110.3 for linear generators. South Coast AQMD’s rulemaking page contains draft documents and working-group materials from the process.
What does this mean for industry?
It means businesses should monitor regulatory developments rather than relying only on an old compliance checklist.
However, a proposed amendment should not be treated as an adopted requirement until officially adopted and effective.
Depending on the applicable engine category and compliance requirement, testing can involve:
NOx Testing
NOx is one of the primary pollutants regulated under Rule 1110.2.
CO Testing
Carbon monoxide provides important information about combustion performance and compliance.
VOC Testing
VOC emissions are also regulated, with applicable limits depending on the engine category.
South Coast AQMD maintains a specific source-test protocol for NOx, CO and VOC testing for stationary internal-combustion engines subject to Rule 1110.2.
Why Professional Engine Emissions Testing Matters
A stationary engine may appear to operate normally while still producing emissions above an applicable limit.
For example:
Engine running normally
↓
Combustion conditions change
↓
NOx/CO/VOC emissions increase
↓
Compliance test fails
↓
Corrective action + retesting
This is why proactive emissions testing can be valuable.
Rule 1110.2 Source Testing Requirements
For applicable source testing, the rule contains detailed requirements.
Among other provisions, applicable testing can require testing during:
Normal operation
Actual duty cycle
Peak load
Minimum practical load
The rule states that certain source testing must include at least 30 minutes during normal operation, plus NOx and CO testing at applicable peak and minimum loads, unless the permit limits operation to a defined load range.
Another important requirement:
The rule states that testing should occur at least 40 operating hours or one week after engine servicing or tuning, as applicable. It also prohibits pre-tests for compliance.
That means testing schedules need to be planned carefully.
Source-Test Protocol: Don’t Leave It Until the Last Minute
One of the biggest compliance mistakes is treating the source-test protocol as paperwork to complete immediately before testing.
Rule 1110.2 requires, for applicable tests, submission of a source-test protocol for written approval at least 60 days before the scheduled test date. The protocol must address items such as:
Engine identification
Permit/application information
Applicable emission limits
Test methods
Number of test runs
Operating loads
VOC sampling requirements
Parameters measured under the Inspection & Monitoring Plan
The rule also requires approval before testing.
That’s why early planning matters.
Protocol → Approval → Testing → Reporting
Testing Contractor Requirements
For applicable Rule 1110.2 source tests, the rule requires use of a contractor approved by the Executive Officer under the Laboratory Approval Program (LAP) for the necessary test methods.
South Coast AQMD also maintains its source-testing methods and procedures, including the dedicated Rule 1110.2 protocol.
Before hiring a testing company, verify:
Appropriate test-method approval
Relevant experience
Qualified personnel
Proper instrumentation
QA/QC procedures
Reporting capability
Familiarity with South Coast AQMD requirements
Source-Test Reporting
Testing doesn’t end when the instruments are removed from the stack.
For applicable Rule 1110.2 testing, the rule requires source-test reports to be submitted to the Executive Officer within 60 days of completion of the test.
A professional testing program therefore includes:
Planning → Field Testing → Data Validation → Calculations → Report Preparation → Submission
CEMS Requirements Under Rule 1110.2
Large engines may have additional continuous monitoring requirements.
The current rule requires NOx and CO CEMS for certain engines rated 1,000 bhp or greater and operating more than 2 million bhp-hours per calendar year.
CEMS can also be required at facilities with applicable engines having a combined rating of 1,500 bhp or greater at the same location and combined fuel usage exceeding 16 × 10⁹ Btu/year, subject to the rule’s provisions and exclusions.
The rule also requires applicable CEMS to comply with relevant requirements under Rules 218 and 218.1, including equipment specifications, certification, operation, recordkeeping, QA and reporting.
This connects Rule 1110.2 directly with CEMS compliance.
Rule 1110.2 also contains Inspection and Monitoring (I&M) requirements.
Applicable operators may need an approved I&M Plan covering items specified by the rule.
South Coast AQMD also provides:
Combustion Gas Periodic Monitoring Protocol
Calibration recordkeeping forms
Periodic monitoring forms
Stability-check forms
Linearity/interference records
through its Rule 1110.2 compliance resources.
Portable Analyzer Testing
Portable combustion analyzers can play an important role in Rule 1110.2 compliance.
South Coast AQMD states that portable-analyzer engine tests required under the I&M provisions must be conducted by a person who has completed an approved training program and received South Coast AQMD certification.
This is important because a portable-analyzer measurement is not simply a matter of taking a reading.
Proper procedure matters.
The person conducting the test needs appropriate training, equipment, calibration and documentation.
Emergency Standby Engines: A Common Compliance Misunderstanding
Many businesses assume:
“It’s an emergency generator, so air-quality rules don’t apply.”
That’s not necessarily correct.
South Coast AQMD identifies an emergency backup generator as a standby ICE or turbine for non-utility power generation that operates no more than 200 hours per year and is used for emergency power failure or routine testing/maintenance, subject to the applicable requirements.
Rule 1110.2 also contains exemptions for certain emergency standby engines limited by permit conditions to 200 hours or less per year, along with other specified categories.
The permit condition matters.
Don’t assume that simply calling an engine an “emergency generator” automatically exempts it from every requirement.
Rule 1110.2 service provider in California
Rule 1110.2 Compliance: Pros & Cons
Advantages of Proactive Compliance
1. Early Problem Detection
Testing can identify elevated emissions before a regulatory deadline.
2. Better Engine Performance
Combustion testing can identify operating problems.
3. Reduced Compliance Risk
Regular monitoring provides better visibility into emissions.
4. Better Documentation
Professional reports create an organized compliance record.
5. Improved Maintenance Planning
Emission trends can help identify equipment problems.
6. Better Preparation for Rule Changes
Facilities that maintain accurate emissions data can make better upgrade decisions.
Potential Challenges
Testing Costs
Professional source testing requires equipment, personnel and laboratory/analytical resources.
Operational Coordination
The engine may need to operate at specific loads during testing.
Protocol Lead Time
Applicable protocols may need regulatory approval well before testing.
Failed Tests
An exceedance can require corrective action and potentially additional testing.
CEMS Costs
Large applicable engines may require continuous monitoring systems.
Recordkeeping
Compliance requires maintaining appropriate records and documentation.
What Happens If an Engine Fails?
A failed test shouldn’t be ignored.
A typical corrective approach is:
1. Identify the Cause
Check:
Fuel system
Air/fuel ratio
Ignition
Engine condition
Catalyst
Control equipment
Operating load
Maintenance history
2. Correct the Problem
Tune, repair or modify the equipment as appropriate.
Natural Gas Engines
Advantages of Proactive Compliance
Testing Costs
Manufacturing
Energy & Power
Oil & Gas
Water & Wastewater
Agriculture
Commercial & Institutional
Don’t Wait Until Your Engine Fails a Compliance Test
Review Rule 1110.2 applicability