Boiler Certification, Tune-Up & Testing California | EES

Boiler Certification, Tune-Up & Testing California | EES

Boiler Certification, Tune-Up & Testing in California: 2026 Compliance Guide for Industrial & Commercial Facilities

Is your boiler operating efficiently—and is it meeting California air-quality requirements?

For industrial, institutional and commercial facilities, boiler compliance is more than keeping equipment running. Depending on the boiler size, fuel, location, permit and applicable air district rules, facilities may need certification, periodic tune-ups, emissions testing, recordkeeping and other compliance activities.

In Southern California, South Coast AQMD Rules 1146, 1146.1 and 1146.2 are particularly important for boilers, steam generators, process heaters and certain water heaters. South Coast AQMD’s current rule book lists Rule 1146 as amended in 2020, Rule 1146.1 as amended in 2018, and Rule 1146.2 as amended in 2024.

For facility owners and EHS managers, the key question is not simply:

“Does my boiler work?”

It is:

“Can my boiler demonstrate compliance with the applicable air-quality requirements?”

This is where professional Boiler Certification, Tune-Up and Testing services become valuable.


What Is Boiler Certification, Tune-Up & Testing?

These are related but different compliance activities.

Boiler Certification

Certification generally involves demonstrating that applicable equipment meets the requirements of the governing air-district rule or certification program.

For example, South Coast AQMD maintains a Certified Boilers List under Rule 1146.2, with the current equipment list updated December 30, 2025.

Boiler Tune-Up

A tune-up evaluates and adjusts combustion performance to help the boiler operate properly while controlling emissions.

Boiler Emissions Testing

Testing measures actual emissions—such as NOx, CO and oxygen—using the applicable regulatory test method.

These activities work together:

Certification → Tune-Up → Testing → Documentation → Compliance


Why Is Boiler Compliance Important in California?

Boilers are combustion sources.

Combustion can produce pollutants including:

  • NOx
  • Carbon monoxide (CO)
  • Particulate matter
  • Greenhouse gases
  • Other combustion-related pollutants

NOx is particularly important because it contributes to ozone and smog formation.

South Coast AQMD states that combustion sources are among the sources of NOx emissions in the region, and its Rule 1146.2 amendments were designed to achieve significant NOx reductions.

For businesses, this means boiler operation can have both:

Environmental consequences + Regulatory consequences


2026 California Boiler Compliance: What’s Changing?

California does not have one identical boiler requirement for every facility.

Requirements can differ between air districts, including:

  • South Coast AQMD
  • Bay Area AQMD
  • San Joaquin Valley APCD
  • Sacramento Metropolitan AQMD
  • San Diego APCD
  • Ventura County APCD
  • Other local air districts

Therefore, a boiler compliance strategy should always begin with:

Facility Location + Permit + Boiler Size + Fuel + Applicable Rule


2026 Update: South Coast AQMD Is Actively Reviewing Rules 1146 & 1146.1

One of the most important developments for 2026 is South Coast AQMD’s ongoing work on Proposed Amended Rule 1146 and Proposed Amended Rule 1146.1.

The proposed rules address:

  • Industrial boilers
  • Institutional boilers
  • Commercial boilers
  • Steam generators
  • Process heaters
  • Small boilers and process heaters

South Coast AQMD held Working Group Meeting #4 on June 25, 2026, as part of the Rule 1146/1146.1 rule-development process.

This is important for facility managers because future amendments could affect:

Emission limits → testing → compliance planning → equipment upgrades

Facilities operating older boilers should therefore monitor rule developments rather than assuming today’s requirements will remain unchanged.


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2026 Update: Rule 1146.2 Has Important Zero-Emission Requirements

South Coast AQMD amended Rule 1146.2 on June 7, 2024, establishing a transition toward zero-emission equipment for certain water heaters, boilers and process heaters.

A major 2026 milestone is:

January 1, 2026

South Coast AQMD’s 2026 compliance-deadline guidance states that certain Type 1 units ≤400,000 Btu/hr and qualifying instantaneous water heaters ≤200,000 Btu/hr installed in new buildings must comply with zero-emission limits.

The practical implication is significant:

Boiler and water-heating equipment planning is changing.

Facilities installing or replacing equipment should evaluate applicable requirements before purchasing equipment, rather than discovering a compliance issue after installation.


What Does a Boiler Tune-Up Actually Do?

A professional tune-up focuses on combustion performance.

Depending on the equipment and applicable rule, the process can include checking:

  • Fuel-to-air ratio
  • Oxygen concentration
  • Carbon monoxide
  • Stack temperature
  • Flame condition
  • Burner operation
  • Draft
  • Combustion-air supply
  • Fuel pressure
  • Operating load
  • Control settings

South Coast AQMD’s Rule 1146 tuning procedures specifically address operating the equipment at a representative firing rate and recording combustion parameters such as stack temperature, oxygen and CO.

The objective:

Efficient combustion + controlled emissions + reliable operation


Why Boiler Tune-Up Is More Than Maintenance

Routine mechanical maintenance keeps equipment operating.

A regulatory tune-up has an additional objective:

Emission control.

For example, poor combustion can contribute to elevated CO or inefficient operation.

Too much excess air can also reduce combustion efficiency.

Too little combustion air can create incomplete combustion and elevated CO.

A properly performed tune-up seeks an appropriate combustion balance while maintaining safe operation.

South Coast AQMD’s tuning procedures explicitly state that tuning must not create unsafe conditions or violate applicable safety requirements, manufacturer specifications or other relevant regulations.


When Is Boiler Tune-Up Required?

This depends on the applicable rule and the specific unit.

For example, Rule 1146.1 contains a tune-up option for certain qualifying units with annual heat input of 18,000 therms or less. Units using this option must be tuned at least twice per year, at intervals of four to eight months, according to the prescribed or manufacturer’s procedure, with records maintained for a rolling 24-month period.

That does not mean every California boiler requires two tune-ups every year.

This distinction is important.

The applicable:

Rule + Unit Size + Fuel + Operating History + Permit

determine what is required.


Boiler Emissions Testing: What Is Measured?

Depending on the applicable regulatory requirement, testing may include:

NOx

Nitrogen oxides are a major regulatory focus for combustion equipment.

CO

Carbon monoxide helps evaluate combustion performance and may be subject to emission limits.

Oxygen

O₂ measurements can be used for combustion analysis and, depending on the rule, emissions corrections.

Other Parameters

Depending on the source, testing may also evaluate:

  • Stack temperature
  • Exhaust flow
  • Fuel consumption
  • Heat input
  • Operating load
  • Control-device parameters

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How Often Does a Boiler Need Emissions Testing?

There is no single California-wide testing interval.

The frequency depends on the applicable rule and equipment.

For example, South Coast AQMD Rule 1146 provides specific compliance-testing provisions. Under one provision, certain units at or above 10 MMBtu/hr have a three-year compliance determination interval, while certain units from 5 to below 10 MMBtu/hr have a five-year interval.

Other requirements may apply depending on the boiler category, compliance option and regulatory program.

Don’t assume your neighbor’s testing schedule applies to your boiler.


Boiler Certification vs. Boiler Testing

These terms are often confused.

CertificationTesting
Demonstrates equipment meets a certification requirementMeasures actual emissions
Often associated with specific equipment categoriesUsually associated with operating equipment
Can apply to equipment models/configurationsMeasures field performance
May be required before installation/operationMay be periodic
Documentation-basedData/measurement-based

South Coast AQMD maintains certified equipment lists to help businesses identify equipment that meets applicable requirements. The current Rule 1146.2 certified-boiler list was updated December 30, 2025.


Why Boiler Testing Can Fail

A boiler doesn’t necessarily fail because it is mechanically broken.

Compliance problems can come from:

1. Incorrect Burner Settings

Improper combustion settings can increase emissions.

2. Excessive CO

Incomplete combustion can produce elevated CO.

3. Excess NOx

Combustion conditions may result in NOx above an applicable limit.

4. Poor Maintenance

Dirty burners, fouled surfaces or degraded components can affect combustion.

5. Incorrect Operating Conditions

A test performed under the wrong load or process conditions may not demonstrate compliance.

6. Aging Equipment

Older boilers may have difficulty meeting newer emissions requirements.

7. Inadequate Documentation

Even when equipment performs properly, missing records can create compliance complications.


The Cost of Ignoring Boiler Compliance

For a facility manager, a boiler compliance problem can quickly become an operational problem.

Potential consequences may include:

Failed emissions test

Investigation

Corrective maintenance

Retesting

Production disruption

Additional engineering expense

Possible regulatory enforcement

The exact consequences depend on the applicable air district, rule, permit and circumstances.

The smarter approach is preventive compliance.


Pros of Professional Boiler Certification, Tune-Up & Testing

✅ 1. Helps Demonstrate Regulatory Compliance

Measured data and proper documentation provide evidence of compliance with applicable requirements.

✅ 2. Improves Combustion Performance

A properly tuned boiler can operate more effectively.

✅ 3. Helps Identify Problems Early

Testing can reveal elevated emissions before they become a larger compliance issue.

✅ 4. Supports Better Maintenance Decisions

Testing data can help identify when burners, controls or other components need attention.

✅ 5. Reduces Compliance Surprises

A planned testing program is safer than waiting for a regulatory deadline.

✅ 6. Supports Equipment Planning

Testing can help determine whether an older boiler can continue operating within applicable limits.


Challenges / Cons

Professional testing also involves costs and planning.

ChallengePotential Impact
Testing costBudget required
Tune-up costTechnician/engineering expense
Production coordinationBoiler access may require scheduling
RetestingAdditional cost if results are unsatisfactory
DocumentationRequires organized recordkeeping
Regulatory changesExisting equipment may face future requirements
Equipment upgradesOlder boilers may require modernization

But there is a difference between a compliance cost and an unexpected compliance crisis.

Planning usually gives a facility more options.


Which Industries Need Boiler Compliance Services?

Potential clients include:

Manufacturing

  • Food processing
  • Pharmaceutical manufacturing
  • Chemical manufacturing
  • Automotive
  • Aerospace
  • Textile
  • Paper
  • Plastics

Institutional

  • Hospitals
  • Universities
  • Schools
  • Government facilities

Commercial

  • Hotels
  • Large commercial buildings
  • Laundry facilities
  • Food-service operations

Industrial

  • Refineries
  • Industrial processing plants
  • Warehouses with process heating
  • Energy facilities

The exact requirements depend on the equipment and jurisdiction.


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Why Hospitals and Large Facilities Should Pay Special Attention

Hospitals, universities and large commercial buildings often rely heavily on boilers for:

  • Steam
  • Hot water
  • Heating
  • Sterilization
  • Laundry
  • Process applications

A boiler compliance issue can therefore affect more than emissions.

It can affect:

Operations + Energy Use + Maintenance + Compliance

This makes proactive testing particularly valuable.


How EES Helps With Boiler Certification, Tune-Up & Testing

Energy Environmental Solutions, Inc. (EES) can support industrial and commercial facilities through the boiler compliance process.

1. Regulatory Review

EES can review:

  • Boiler size
  • Fuel type
  • Permit conditions
  • Applicable air-district rule
  • Testing frequency
  • Emission limits

2. Boiler Certification Support

For applicable equipment, EES can help facilities understand certification requirements and documentation.


3. Boiler Tune-Up

EES can support combustion tune-up programs designed around applicable regulatory and equipment requirements.

The process can evaluate:

O₂ + CO + Stack Temperature + Firing Rate + Combustion Conditions


4. NOx Testing

EES can perform applicable boiler NOx emissions testing to determine whether the source meets its regulatory requirements.


5. CO Testing

Carbon monoxide testing can help evaluate combustion performance and applicable compliance limits.


6. Source-Test Protocol Development

Before testing, EES can prepare a test protocol addressing:

  • Applicable rule
  • Pollutants
  • Test methods
  • Operating conditions
  • Sampling requirements
  • QA/QC
  • Calculations
  • Reporting

7. Compliance Testing

EES can coordinate the field-testing program with facility personnel to minimize operational disruption.


8. Engineering Calculations

Testing data can be evaluated and converted into the required regulatory units.


9. Compliance Reporting

EES can prepare technical documentation for applicable regulatory reporting and compliance records.


EES Boiler Compliance Process

STEP 1 — REVIEW

Permit + Boiler + Rule

STEP 2 — IDENTIFY

Emission Limits + Testing Requirements

STEP 3 — PLAN

Test Protocol + Operating Conditions

STEP 4 — TUNE

Optimize Combustion

STEP 5 — TEST

NOx + CO + O₂ + Applicable Parameters

STEP 6 — ANALYZE

Review Results + QA/QC

STEP 7 — REPORT

Compliance Documentation

STEP 8 — IMPROVE

Corrective Action / Retesting if Required


Why Choose EES for Boiler Testing?

A boiler test should not be treated as an isolated laboratory exercise.

Your testing company should understand:

The boiler → the combustion process → the air district → the rule → the test method → the compliance limit

That’s the difference between simply collecting emissions data and building a useful compliance program.


2026 Boiler Compliance Checklist

Before your next boiler test or tune-up, ask:

  • Is the boiler properly permitted/registered?
  • What is the rated heat-input capacity?
  • What fuel does it use?
  • Which California air district regulates the facility?
  • Which boiler rule applies?
  • Is certification required?
  • Is a tune-up required?
  • When was the last tune-up?
  • When was the last emissions test?
  • What are the applicable NOx limits?
  • What are the applicable CO requirements?
  • Is a source-test protocol required?
  • Is agency notification/approval required?
  • Are operating conditions specified?
  • Are records current?
  • Has the boiler or burner been modified?
  • Has the applicable rule changed?

2026: Why Facilities Should Review Their Boiler Compliance Program Now

The regulatory environment is moving toward lower-emission and zero-emission technologies.

South Coast AQMD’s 2026 rule-development work includes proposed amendments to Rules 1146 and 1146.1.

At the same time, Rule 1146.2 has already introduced significant zero-emission requirements for certain equipment categories, including requirements taking effect January 1, 2026.

This creates a strategic question for facility owners:

Should you continue maintaining the existing boiler, upgrade it, replace the burner, or transition to another technology?

Current emissions-testing data can help answer that question.


Don’t Wait for a Failed Boiler Test

A failed compliance test is often the worst time to start investigating your boiler.

Instead:

Test → Analyze → Tune → Verify → Document

This approach gives facility managers a better opportunity to identify problems before they become emergencies.


Need Boiler Certification, Tune-Up & Testing in California?

EES Can Help Your Facility Stay Ahead of Compliance Requirements

Energy Environmental Solutions, Inc. (EES) provides professional environmental testing and compliance services for industrial, institutional and commercial facilities.

Our related services include:

Boiler Certification
Boiler Tune-Up
Boiler Emissions Testing
NOx Testing
CO Testing
O₂ Testing
Source Testing
Air Quality Compliance Testing
Test Protocol Development
Rule 1146 Compliance
Rule 1146.1 Compliance
Rule 1146.2 Compliance
Process Heater Testing
Steam Generator Testing
Thermal Oxidizer Testing
RTO Testing
CEMS / RATA / CGA
Particulate Matter Testing
Air Toxics Testing

Tune Your Boiler. Test Your Emissions. Protect Your Compliance.

Energy Environmental Solutions, Inc. (EES)
Phone: 714-630-5210 | 714-630-7844
Email: info@sourcetester.com
Website: sourcetester.org

Rule 1147 California 2026 | NOx Testing & Compliance Services | Source Tester | EES

Rule 1147 California 2026 | NOx Testing & Compliance Services | Source Tester | EES

Rule 1147 in California 2026: Latest Updates, Pros, Cons & How EES Helps Industries

Rule 1147 — NOx Reductions from Miscellaneous Sources is an important South Coast AQMD regulation for certain fuel-fired combustion equipment in Southern California. It is designed to reduce nitrogen oxide (NOx) emissions while limiting carbon monoxide (CO) from permitted gaseous- and liquid-fuel-fired equipment that is not covered by another applicable Regulation XI rule.

Important: Rule 1147 is not a statewide California rule. It applies within the South Coast AQMD jurisdiction to equipment meeting the rule’s applicability requirements. Other California air districts have their own rules and permit requirements.

For industrial facilities operating spray-booth heaters, ovens, dryers, furnaces, thermal oxidizers, afterburners, vapor incinerators, tenter-frame dryers, process heaters and other miscellaneous combustion equipment, understanding the current Rule 1147 requirements can be critical to avoiding compliance problems.

Energy Environmental Solutions, Inc. (EES) helps facilities with Rule 1147 source testing, NOx testing, CO testing, compliance test protocol development, emissions testing, CEMS/RATA/CGA, engineering studies and regulatory reporting.


What Is South Coast AQMD Rule 1147?

Rule 1147 was adopted in 2008 and most recently amended on May 6, 2022. The current South Coast AQMD rulebook identifies it as Rule 1147 — NOx Reductions from Miscellaneous Sources.

The rule applies to certain gaseous- and/or liquid-fuel-fired combustion equipment requiring a South Coast AQMD permit, when another Regulation XI rule does not already apply to the unit.

Covered equipment can include categories such as:

  • Thermal oxidizers
  • Catalytic oxidizers
  • Afterburners
  • Vapor incinerators
  • Ovens
  • Dryers
  • Dehydrators
  • Heaters
  • Furnaces
  • Kilns
  • Calciners
  • Cookers
  • Roasters
  • Tenter-frame dryers
  • Fabric and carpet dryers
  • Remediation units
  • Certain liquid-fuel-fired equipment

The exact applicability depends on the equipment, fuel, rated heat-input capacity, permit status and other provisions of the rule.


Latest 2026 Rule 1147 updates, NOx and CO testing requirements, pros and cons, source-test frequencies and how EES helps South Coast AQMD facilities stay compliant.

Why Does Rule 1147 Matter in 2026?

The environmental reason is straightforward: NOx contributes to ozone and particulate pollution, making NOx reductions an important component of regional air-quality planning.

South Coast AQMD’s Rule 1147 technology assessment explains that the rule’s NOx reductions are an important part of the region’s attainment strategy for federal and state ambient air-quality standards, including standards for ozone, PM2.5 and PM10.

And the need for effective air-quality controls remains highly relevant in 2026. South Coast AQMD’s current 2026 news and regulatory activity includes ozone advisories, particulate-related actions, toxic-air-contaminant rulemaking and additional emissions-control initiatives.

The compliance message for industry:

NOx compliance is not simply about installing a burner or combustion system. Facilities need to demonstrate that applicable equipment actually operates within its required emissions limits.


Latest Rule 1147 Updates for 2026

1. The Current Rule Remains the May 6, 2022 Version

As of August 2026, South Coast AQMD’s current Regulation XI listing identifies Rule 1147 as amended May 6, 2022. There is no indication on the current official rule listing of a newer 2026 amendment to Rule 1147 itself.

That distinction is important.

“Latest 2026 update” does not mean Rule 1147 itself was amended in 2026. Instead, facilities need to consider the current Rule 1147 requirements alongside their current permits and other 2026 regulatory developments.


2. Source Testing Remains a Major Compliance Requirement

For units subject to Rule 1147 with NOx emissions of at least 1 pound per day, the rule requires source testing to demonstrate compliance with applicable NOx and CO limits in the rule or permit.

The testing frequency depends on the equipment’s Rated Heat Input Capacity:

Rated Heat Input CapacitySource-Test Frequency
< 10 MMBtu/hrEvery 5 calendar years
≥ 10 and < 40 MMBtu/hrEvery 3 calendar years
≥ 40 MMBtu/hrEvery calendar year
≥40 MMBtu/hr with ≥6 months shutdownTest within 90 days after resumed operation, subject to the rule’s conditions

These intervals are specified in Rule 1147 paragraph (h)(12).

This is one of the most important points for facility managers:

Your source-test due date can depend directly on the equipment’s rated heat-input capacity and NOx emissions.


3. Rule 1147 Requires an Approved Test Protocol

Source testing isn’t simply a matter of sending a technician to the facility and taking measurements.

Rule 1147 requires the operator to submit a source-test protocol to the Executive Officer for approval no later than 90 days before the scheduled source test, subject to the rule’s timing provisions.

For subsequent compliance determinations, protocol resubmission may not be necessary when an approved protocol already exists, provided the unit has not been modified in a way requiring a permit modification and the applicable limits have not become more stringent.

Why does this matter?

Because an improperly planned test can create unnecessary delays, additional costs and potentially unusable compliance data.

Test planning should happen before the test day—not after.


4. Independent Testing Is Required

Rule 1147 requires compliance determinations to be conducted by an independent contractor approved by the Executive Officer under the Laboratory Approval Program for the applicable test methods.

That means facilities should verify that their selected testing company has the appropriate qualifications and approvals for the methods being used.

This is particularly important when a facility is approaching a regulatory deadline.


5. Recordkeeping Still Matters

Rule 1147 requires source-test reports and maintenance records to be maintained for at least five years and made available to South Coast AQMD personnel upon request.

This means compliance doesn’t end when the testing crew leaves the site.

Your facility should maintain:

  • Source-test reports
  • Maintenance records
  • Rated heat-input information
  • Fuel records where applicable
  • CEMS records where applicable
  • Compliance documentation
  • Approved testing protocols
  • Equipment modification records

Good documentation can be as important as good testing.


What Emission Limits Does Rule 1147 Establish?

Rule 1147 contains different NOx and CO limits depending on the equipment category, fuel type, process temperature and whether the unit is an in-use unit or subject to the newer Table 2 requirements.

For example, Table 1 includes different limits for equipment such as thermal oxidizers, ovens, heaters, dryers and other combustion equipment.

For certain gaseous-fuel-fired thermal oxidizers, catalytic oxidizers, afterburners and vapor incinerators, the Table 1 NOx limit is 60 ppmv or 0.073 lb/MMBtu, with a CO limit of 1,000 ppmv.

Table 2 establishes more stringent requirements for applicable equipment.

For example, gaseous-fuel-fired thermal oxidizers, catalytic oxidizers, afterburners and vapor incinerators are listed at 20 ppmv or 0.024 lb/MMBtu NOx under Table 2.

Do not assume these numbers automatically apply to your equipment. The applicable limit must be determined from the rule, equipment category, permit and compliance schedule.


A Key 2026 Compliance Option: Less Than 1 Pound of NOx Per Day

Rule 1147 provides an alternative pathway for certain units.

An owner or operator may elect to comply by demonstrating NOx emissions below 1 pound per day averaged over a calendar month, or by meeting an existing permit limit below 1 pound per day, whichever is applicable under the rule.

However, if the facility fails to demonstrate compliance with that option, additional permit and compliance requirements can be triggered.

This makes accurate emissions calculations and recordkeeping particularly important.


Pros of Rule 1147 Compliance

1. Lower NOx Emissions

The primary environmental benefit is reduced NOx emissions from miscellaneous combustion sources.

Lower NOx contributes to regional efforts to address ozone and particulate pollution. South Coast AQMD describes Rule 1147’s NOx reductions as an important component of its attainment strategy.

2. Better Combustion Performance

Testing can reveal problems involving burners, combustion-air systems, controls or operating conditions.

A failed or borderline test can therefore become an opportunity to identify equipment problems.

3. More Reliable Compliance Data

Professional source testing provides measured emissions data instead of relying exclusively on theoretical calculations or equipment specifications.

4. Better Maintenance Decisions

Testing results can help environmental and maintenance teams identify whether combustion equipment needs adjustment, repair or modernization.

5. Improved Regulatory Readiness

Maintaining current testing and maintenance records can make inspections and compliance reviews easier.


Cons and Challenges of Rule 1147

1. Testing Costs

Source testing requires specialized equipment, qualified personnel, laboratory or analytical resources and technical reporting.

2. Production Disruption

Testing may need to occur under specific operating conditions, which can require coordination with production schedules.

3. Protocol Approval Takes Planning

The requirement for an approved test protocol means facilities need to start preparing well before the actual test date.

4. Equipment Modifications Can Change Requirements

Changes to burners, combustion systems, fuel systems or operating conditions may affect the compliance pathway.

5. Multiple Equipment Categories

Rule 1147 covers a wide variety of equipment, so the correct testing approach is not identical for every unit.

6. Testing at the Wrong Operating Condition Can Create Problems

Rule 1147 specifies operating conditions for compliance determinations, including testing at the maximum heat-input range at which the unit normally operates and additional conditions for specified equipment categories.


What Equipment Should California Facilities Review?

If your facility is located in the South Coast AQMD jurisdiction, review Rule 1147 applicability if you operate permitted fuel-fired equipment such as:

Thermal Oxidizers • Afterburners • Vapor Incinerators • Ovens • Dryers • Heaters • Furnaces • Kilns • Tenter-Frame Dryers • Fabric Dryers • Carpet Dryers • Cookers • Roasters • Dehydrators • Remediation Units

The actual applicability must be confirmed against the current rule and permit.


Latest 2026 Rule 1147 updates, NOx and CO testing requirements, pros and cons, source-test frequencies and how EES helps South Coast AQMD facilities stay compliant.

How EES Helps With Rule 1147 Compliance

Energy Environmental Solutions, Inc. (EES) provides technical testing and environmental compliance support for industrial facilities.

Rule 1147 Source Testing

EES can assist with testing programs designed to demonstrate applicable NOx and CO emission compliance.

Compliance Test Protocol Development

EES helps develop testing protocols covering:

  • Sampling locations
  • Applicable test methods
  • Operating conditions
  • Test runs
  • QA/QC
  • Calculations
  • Reporting requirements

NOx Testing

Accurate NOx measurements are central to Rule 1147 compliance.

CO Testing

Rule 1147 also establishes CO requirements for applicable equipment, making CO testing an important part of many compliance demonstrations.

CEMS / RATA / CGA

For facilities using continuous emissions monitoring systems, EES can support applicable CEMS, RATA and CGA requirements.

Rule 1147 also provides circumstances in which qualifying periodic monitoring or CEMS relative-accuracy testing may be used as part of the source-testing compliance schedule.

Engineering Studies

EES can help facilities evaluate combustion-system performance, emissions trends and potential compliance strategies.

Regulatory Reporting

Testing isn’t complete until the data have been properly evaluated and documented.

EES can help prepare organized technical reports and supporting documentation.


Rule 1147 Compliance Testing Process

A professional compliance project generally follows this sequence:

1. Review the Permit
Determine the applicable permit limits and conditions.

2. Confirm Rule Applicability
Determine whether Rule 1147 applies to the unit.

3. Determine Testing Frequency
Review NOx emissions and rated heat-input capacity.

4. Develop the Test Protocol
Select appropriate methods and operating conditions.

5. Submit for Approval
Follow South Coast AQMD protocol-approval requirements.

6. Conduct Field Testing
Perform NOx, CO and supporting measurements.

7. QA/QC Review
Review calibration, field data and calculations.

8. Calculate Emissions
Determine compliance with the applicable limit.

9. Prepare the Report
Document the test conditions, methods, results and conclusions.

10. Maintain Records
Retain required documentation for the applicable period.


Why Proactive Rule 1147 Testing Makes Sense in 2026

South Coast AQMD states that its compliance staff conduct regular inspections to ensure equipment and processes are operating in compliance with applicable clean-air rules.

The agency also explains that failure to correct a Notice to Comply can lead to a Notice of Violation and penalties, while continuing violations can result in daily penalties.

That is why waiting until an inspector identifies a problem is a risky compliance strategy.

A better approach:

Know your limit.
Know your test date.
Know your operating conditions.
Know your documentation.


Rule 1147 Compliance Checklist for 2026

Before your next test, review:

  • Is the unit subject to Rule 1147?
  • Is the current permit available?
  • What NOx limit applies?
  • What CO limit applies?
  • What is the unit’s rated heat-input capacity?
  • Is NOx ≥1 lb/day?
  • When was the last approved source test?
  • Is the next test due?
  • Has the test protocol been approved?
  • Has the equipment been modified?
  • Are operating conditions representative?
  • Are maintenance records current?
  • Are required fuel meters installed and maintained?
  • Are five years of required records available?
  • Is the testing contractor appropriately approved?

2026 Bottom Line

Rule 1147 remains an important South Coast AQMD NOx-compliance requirement in 2026. Although the rule itself was last amended on May 6, 2022, its current requirements continue to govern applicable miscellaneous combustion equipment, including specific source-testing frequencies, test protocols, NOx/CO limits and recordkeeping requirements.

For facilities with applicable equipment, the biggest mistake is assuming that “the equipment has always passed” means the next test can be treated casually.

Equipment ages. Burners are replaced. Processes change. Permits change. Operating conditions change.

And compliance requirements need to be checked against the current rule and permit.

Is your Rule 1147 source test due in 2026?

Are your NOx and CO emissions within the applicable limits?

Is your test protocol ready for South Coast AQMD approval?

Are your records inspection-ready?

If you’re uncertain, now is the right time to review your equipment and testing schedule.


Need Rule 1147 Testing in California?

Energy Environmental Solutions, Inc. (EES) helps industries with:

Rule 1147 Source Testing | NOx Testing | CO Testing | Compliance Test Protocol Development | Thermal Oxidizer Testing | Oven & Dryer Testing | Furnace Testing | Source & Stack Testing | CEMS | RATA | CGA | Engineering Studies | QA/QC | Regulatory Reporting

Measure Emissions. Verify Compliance. Protect Your Operations.

EES — Energy Environmental Solutions, Inc.

Phone: 714-630-5210 | 714-630-7844
Email: info@sourcetester.com
Website: sourcetester.org