(Adopted: 11/06/81; Rescinded: mm/dd/yy)

AVAQMD Rule 1110 1110-1

Emissions From Stationary IC Engines (Demonstration)

D1: 11/15/12

RULE 1110

Emissions From Stationary Internal Combustion Engines 

(Demonstration)

(a) Definitions

For purposes of this rule, the following definitions shall apply:

(1) A Stationary Internal Combustion Engine (engine) is any spark ignition (Otto cycle) 

internal combustion engine that is operated at a specific site for more than one year or is 

attached to a foundation at that site.

(2) A Rich-Burn Engine is an engine that is operated with an exhaust stream oxygen 

concentration of less than one percent by volume.

(3) A Lean-Burn Engine is an engine that is operated with an exhaust stream oxygen 

concentration greater than one percent by volume.

(4) An Existing Engine is an engine that prior to November 6, 1981:

(A) has been issued a valid Permit to Construct or Operate by the District, or

(B) Is in operation, including those operating pursuant to the provisions of District 

Rule 219(b)(1), or

(C) Is subject to review due to submittal of an application for Permit to Construct or 

Operate which has been deemed complete by the Executive Officer.

(5) Output is the shaft output form the engine plus energy reclaimed by any heat recovery 

system, subject to the approval of the Executive Officer.

(6) Rated Brake Horsepower is the rating specified by the engine manufacturer.

(b) Requirements

(1) Owners and/or operators of more than 5,000 total installed rated brake horsepower of 

existing engines shall participate in a program to demonstrate the effectiveness of

methods for the reduction of oxides of nitrogen emissions from such engines, where:

(A) Rich-burn engines demonstrate that:
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Emissions From Stationary IC Engines (Demonstration)

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(i) Oxides of nitrogen emissions do not exceed 0.28 microgram per joule 

output (0.75 g/bhp-hr), or

(ii) These engines have been modified or equipped with control devices 

to reduce oxides of nitrogen emissions by 90 percent, or

(iii) Alternate emission limits of 48 ppm by volume oxides of nitrogen, 

corrected to 15 percent oxygen by volume, or limits as allowed by 

Attachment "A" are not exceeded, or 

(iv) With control equipment installed and operating the emission limits of 

rich-burn engines, subsection (i), (ii) and (iii) above, cannot be met. 

For such engines the Executive Officer may alter emission limits and 

require continuation of testing, after studying costs, to provide 

meaningful information.

(B) Lean-burn engines demonstrate that:

(i) Oxides of nitrogen emissions do not exceed 0.56 microgram per joule 

output (1.5 g/bhp-hr), or

(ii) These engines have been modified or equipped with control devices 

to reduce oxides of nitrogen emissions by 80 percent, or

(iii) Alternate emission limits of 96 ppm by volume oxides of nitrogen, 

corrected to 15 percent oxygen by volume, or limits as allowed by 

Attachment "A" are not exceeded, or

(iv) With control equipment installed and operating the emission limits of 

lean-burn engines, subsections (i), (ii) and (iii) above, cannot be met. 

For such engines the Executive Officer may alter emission limits and 

require continuation of testing, after studying costs, to provide 

meaningful information.

(C) The number of demonstration engines to be selected for testing by each owner 

and/or operator are determined from the Table of Sample Requirements RichBurn Engines and Table of Sample Requirements Lean-Burn Engines below, 

except for substitutions allowed by the Executive Officer, but the total test 

engine horsepower shall not exceed five percent of the total horsepower of all 

engines under the control of the same owner and/or operator.

The engines selected for testing shall show as much diversification of engine 

model and control system as possible and the selection shall be subject to the 

approval of the Executive Officer.
AVAQMD Rule 1110 1110-3

Emissions From Stationary IC Engines (Demonstration)

D1: 11/15/12

(i) TABLE OF SAMPLE REQUIREMENTS

RICH-BURN ENGINES

No. of Rich-Burn

Engines Operated Ranges of

In District Each Rated Brake No. of

Operated At Least Horsepower Demonstration

2,000 hr/yr Per Engine Engines Required

20 or less 50 to 200 None

21 to 50 50 to 200 1

51 to 80 50 to 200 2

over 80 50 to 200 3

7 or less 201 to 500 None

8 to 15 201 to 500 1

over 15 201 to 500 2

7 or less 501 to 1,000 None

8 to 15 501 to 1,000 1

over 15 501 to 1,000 2

4 or less over 1,000 None

5 to 10 over 1,000 1

over 10 over 1,000 2

(ii) TABLE OF SAMPLE REQUIREMENTS FOR

LEAN-BURN ENGINES

No. of Lean-Burn

Engines Operated Ranges of

in District Each Rated Brake No. Lean-Burn

Operated At Least Horsepower Demonstration

2,000 hr/yr Per Engine Engines Required

6 or less 500 and over 500 None

7 to 15 500 and over 500 1

16 to 24 500 and over 500 2

Over 24 500 and over 500 3

(D) Notwithstanding provisions of section (C), where an owner and/or operator has 

engines totaling more than 5,000 installed rated brake horsepower which operate 

more than 2,000 hours per year each, he shall provide at least one demonstration 

engine for the test program.
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Emissions From Stationary IC Engines (Demonstration)

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(E) The hours operated by test engines in the demonstration program shall be 

recorded in log books or by elapsed time recorders.

(F) The owner and/or operator shall submit to the Executive Officer the list by 

model and rating of all his engines, the list of selected test engines which are to 

be retrofitted with control devices or engine modifications, and the test plan, 

prepared following the guidelines provided by the Executive Officer, for the 

demonstration program by January 5, 1982. After approval of the selected test 

engines and test plan by the Executive Officer, the owner and/or operator shall:

(i) Have rich-burn engines modifications completed and control systems 

installed and operating within six months, and

(ii) Have lean-burn engines modifications completed and control systems 

installed and operating within twenty-four months, or

(iii) Have received approval from the Executive Officer for an extension 

in program schedule because of nonavailability of control equipment 

and/or support services, or

(iv) Received approval from the Executive Officer for delay in program 

implementation, not to exceed 12 months, because of funding 

problems (for Public Service Agencies).

(G) Sequential measurements for oxides of nitrogen reduction, along with 

measurements of concentrations of oxygen, carbon monoxide, carbon dioxide, 

total hydrocarbons, and non-methane hydrocarbons by method referenced in 

Attachment "B" or equivalent, are made by the owner and/or operator within the 

first month of operation and, at a minimum, after each 2,000 hours of operation 

or each 6 months of operation, whichever comes first. Measurements of 

ammonia shall be made if deemed necessary by the Executive Officer.

(H) The test program continues for at least 12 consecutive months or until 4,000 

hours of operation are accumulated for each test engine, whichever occurs first.

(I) Breakdown or failure of control equipment to control oxides of nitrogen 

emissions within allowable limits of this rule during the program for periods 

exceeding forty-eight hours shall be summarized in a monthly report to the 

Executive Officer, together with a description of the corrective measures 

undertaken and/or to be undertaken.

(J) Test results shall be reported to the Executive Officer within sixty days after 

completion of each test period.

(2) After oxides of nitrogen control device installation or engine modifications a person 

shall not operate a test engine without periodic manual air-fuel ratio adjustments or 

automatic controls to minimize the discharge of carbon monoxide (CO) into the 

atmosphere.
AVAQMD Rule 1110 1110-5

Emissions From Stationary IC Engines (Demonstration)

D1: 11/15/12

(3) Notwithstanding Rule 219, owners and/or operators of demonstration engines and/or 

control devices shall apply for permits to construct and operate the demonstration 

engines and/or control devices. A test engine with control equipment will be 

considered a single permit unit.

(4) If an owner and/or operator participating in the test program meets the other 

requirements of this rule, the failure of his control equipment to meet the specified 

emission limits will not constitute a violation of the rule.

(5) Owners and/or operators may apply engine test program results from this District and 

from other adjacent counties provided:

(A) That the subject engine is, or would be considered in the case of an adjacent 

county, an existing engine; and

(B) That other requirements of this rule are met; and

(C) The control was not installed to comply with the requirements of any other nondemonstration rule or regulation, including mitigations provided as offsets or 

emission reductions credits for New Source Review, Prevention of Significant 

Deterioration, or Emission Banking.

(6) Owners and/or operators may appeal to the South Coast Air Quality Management Hearing 

Board:

(A) Any decision of the Executive Officer to continue a test program when costs are 

excessive.

(B) A requirement to test selected engines which are deemed to be obsolete for 

purposes of application of NOx control technology.

(C) Any decision of the Executive Officer to include an owner/operator in the test 

program, if such owner/operator is included in the program due to engines 

which will be permanently removed from service no later than three months 

after the dates specified in subsection (b)(1)(F)(i) or (b)(1)(F)(ii), as appropriate.

(7) Engines tested in this Demonstration Program shall be permitted to operate with the 

Nox control system used under this rule for a period of ten years from November 6, 

1981 and shall not be subject to conditions of any other subsequent NOx rule during 

that ten-year period.
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Emissions From Stationary IC Engines (Demonstration)

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(c) Exemptions

(1) The provisions of this rule shall not apply to:

(A) Existing engines with less than 50 brake horsepower rating.

(B) Existing non-carbureted turbocharged four-stroke and existing two-stroke Otto 

cycle engines all less than 500 brake horsepower rating.

(C) Engines used directly and exclusively for agricultural operation necessary for 

the growing of crops, or the raising of fowl or animals.

(D) Diesel cycle engines or gas turbines.

(E) Emergency standby engines which operate only as temporary replacements for 

primary mechanical or electrical power sources during periods of fuel or energy 

shortage or while the primary power source is undergoing repairs.

(F) Engines used exclusively for fire fighting operations.

[SIP: Approved 5/3/84, 49 FR 18822, 40 CFR 52.220(c)(121)(i)(C)]
AVAQMD Rule 1110 1110-7

Emissions From Stationary IC Engines (Demonstration)

D1: 11/15/12

ATTACHMENT A

Alternative Emission Limit to Limit

the Oxides of Nitrogen (NOx) Emissions

from Stationary Internal Combustion Engines

For stationary internal combustion engines, emissions of oxides of nitrogen shall not exceed an 

emission limit as determined by the following equation:

EMISSION LIMIT = STANDARD x UNIT EFFICIENCY

STANDARD EFFICIENCY

The STANDARD is 48 ppm NOx for rich-burn or 96 ppm for lean-burn as corrected to 15 percent 

oxygen at an engine STANDARD EFFICIENCY of 30 percent. 

UNIT EFFICIENCY equals the total shaft output and reclaimed heat from any heat recovery system 

divided by the energy input (as determined by a fuel measuring device accurate to + 5 percent and 

based on the higher heating value of the fuel). Any engine which has a tested efficiency greater than 

30 percent is allowed a 30 percent unit efficiency for the purpose of this limitation.

The volume concentration (ppm) of the oxides of nitrogen (NOx) shall be corrected to 15 percent 

oxygen (O2) on a dry basis as follows:

20.9% - 15%

PPM NOx (15% O2) = PPM NOx (measured) x measured

20.9% - % O2
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Emissions From Stationary IC Engines (Demonstration)

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ATTACHMENT B

Modified EPA Method 20

For the purpose of this rule, the following modifications shall be applied to EPA Reference Method 20 

as published in the Federal Register on September 10, 1979.

(1) General Note - All references to SO2 of sulfur measurement shall be deleted.

(2) Section 4.1.4 - The NOx to NO converter as shown in Figure 20.1 is normally integrated into 

the NOx analyzer. In addition, the deletion of the converter shall not be an option as it presently is in 

Method 20.

(3) Section 4.3 - Calibration gases shall be at 0, 50 percent, and 90 percent of full scale. The full 

scale value shall be selected so that the measured value is approximately 50 percent of scale.

(4) Section 6.1.2 - Delete all references to a preliminary O2 traverse; however, O2 shall be 

measured continuously during the test.

(5) Section 6.1.2.1 - To allow for very small cross sections the minimum number of points shall be 

adjusted at the discretion of the Executive Officer.

(6) Section 6.2 - Testing shall be at actual load conditions. The test period shall be a minimum of 

fifteen minutes per load condition to determine compliance initially. However, if the source is not in 

compliance after the initial fifteen minutes, the test shall be continued for at least one hour and fortyfive minutes. The stack shall be traversed initially to determine the degree of stratification in the stack. 

Sampling time at each traverse point shall be a minimum of two minutes plus system response time. 

The remainder of the test period shall be with the probe inlet at the average point.

(7) An ultimate analysis or equivalent shall be performed on the fuel fired using ASTM Method 

D3178-74 or D3176 (liquid fuels) or D1946-67 (72) (gaseous fuels) as applicable, to determine the 

theoretical maximum concentration in the flue gases shall not deviate by more than an amount 

specified by the Executive Officer, from the predicted O2 concentration based on the concurrent CO2

measurement and the ultimate analysis.