CALIFORNIA AIR RESOURCES BOARD 

APCD/AQMD RULE EVALUATION FORM – Page 1 

(Electronic Format) 

I. GENERAL INFORMATION

District: South Coast Air Quality Management District

Rule No(s): 1146.1 Date adopted/Amended/Rescinded: September 5, 2008

Rule Title(s): 1146.1 - Emissions of Oxides of Nitrogen from Small Industrial, Institutional, and Commercial 

Boilers, Steam Generators, and Process Heaters

Date Submitted to ARB: February 5, 2010

If an Amended Rule, Date Last Amended (or Adopted): May 13, 1994

Is the Rule Intended to be sent to the U.S. EPA as a SIP Revision? Yes No (If No, do not complete remainder of form)

District Contact: Joe Cassmassi Phone Number: 909-396-3155 E-mail Address: jcassmassi@aqmd.gov

Narrative Summary of New Rule or Rule Changes: New Rule Amended Rule 

Amended Rule 1146.1 further reduces NOx emissions from medium-size boilers, steam generators, and process 

heaters with maximum rated heat input capacities between 2 and 5 million BTU per hour by lowering the 

applicable NOx emission limits beginning 2012 through 2015, depending on type of fuel and burner used. In an 

effort to improve compliance, the amended rule significantly strengthens the monitoring requirements of the rule. 

The amendment also harmonizes the NOx compliance limits with those limits in amended Rule 1146 – Emissions 

of Oxides of Nitrogen from Industrial, Institutional, and Commercial Boilers, Steam Generators, and Process 

Heaters.

Pollutant(s) Regulated by the Rule (Check): ROG (NOx) SO2 

 (CO) PM TAC (name): 

II. EFFECT ON EMISSIONS

Complete this section ONLY for rules that, when implemented, will result in quantifiable changes in emissions. Attach reference(s) for emission 

factor(s) and other information. Attach calculation sheet showing how the emission information provided below was determined. 

Net Effect on Emissions: Increase* Decrease** N/A 

Emission Reduction Commitment in SIP for this Source Category: 

There was an emission reduction commitment in the 2007 AQMP of 2.0 tons/day from Control Measure 

MCS-01. This control measure also includes reductions from sources subject to Rules 1146 and 1110.2.

Inventory Year Used to Calculate Changes in Emissions: 2002 (baseline from 2007 AQMP inventory) 

Area Affected: SCAQMD
 

CALIFORNIA AIR RESOURCES BOARD 

APCD/AQMD RULE EVALUATION FORM - Page 2 

(Electronic Format) 

Baseline Inventory in the SIP for the Control Measure1: 0.42 tons/day NOx (2002 Annual Average); 0.47 tons/day NOx 

(2014 Annual Average); and 0.60 tons/day NOx (2023 Summer Planning).

Emissions Reduction Commitment in the SIP for the Control Measure1,2: 0.29 tons/day NOx (2014 Annual Average); and 

0.42 tons/day NOx (2023 Summer Planning).

Revised Baseline Inventory (if any): N/A 

Revised Emission Reduction Estimate (if developed): N/A.

Note that the district’s input to the Rule Evaluation Form will not be used as input to the ARB’s emission forecasting and 

planning. 

III. SOURCES/ATTAINMENT STATUS

District is: Attainment Nonattainment Split 

Approximate Total Number of Small (<100 TPY) Sources Affected by this Amendment: 1,072

Percent in Nonattainment Area: NA

Number of Large (> 100 TPY) Sources Controlled: N/A Percent in Nonattainment Area: N/A

Name(s) and Location(s) (city and county) of Large (> 100 TPY) Sources Controlled by Rule (Attach additional sheets as 

necessary): N/A

IV. EMISSION REDUCTION TECHNOLOGY

Does the Rule Include Emission Limits that are Continuous? Yes No 

If Yes, Those Limits are in Section(s) (c) of the Rule. 

Other Methods in the Rule for Achieving Emission Reductions are: On or after January 1, 2015 or during burner 

replacement, whichever occurs later, owners or operators of low fuel use units (i.e., ≤ 18,000 therms per year) will be 

required to replace with lower NOx level 30 ppm burners. 

V. OTHER REQUIREMENTS

The Rule Contains: 

Emission Limits in Section(s): (c) Work Practice Standards in Section(s): N/A

Recordkeeping Requirements in Section(s): (d) Reporting Requirements in Section(s): (c), (d), and (e) 

 

1

 The NOx emission baseline and reductions only reflect the Rule 1146.1 portion of the Control Measure.

2

 NOx reductions beyond 2014 would be obtained from the low-fuel usage units (i.e., ≤ 18,000 therms per year) through burner 

replacement. 
 

5/1/2002 

CALIFORNIA AIR RESOURCES BOARD 

APCD/AQMD RULE EVALUATION FORM - Page 3 

(Electronic Format) 

VI. IMPACT ON AIR QUALITY PLAN

 No Impact Impacts RFP Impacts attainment 

Discussion: This amendment of Rule 1146.1 will reduce emissions of NOx to help achieve compliance 

with ambient air quality standards for ozone and particulate matter.