UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

REGION IX AIR DIVISION

Technical Support Document 

for

EPA’s Direct Final Rulemaking

for the

California State Implementation Plan

Ventura County Air Pollution Control District Rule 74.11.1

Large Water Heaters and Small Boilers

Prepared by: Nicole Law

February 2014
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Agency: Ventura County Air Pollution Control District

(VCAPCD)

SIP Approved Rule: Rule 74.11.1 – Large Water Heaters and Small Boilers

Adopted – September 14, 1999

Submitted – January 21, 2000

EPA Approved – December 20, 2000 (65 FR 79752)

Superseded Submittals: none

Subject of this TSD: Rule 74.11.1 – Large Water Heaters and Small Boilers

Amended – September 11, 2012

Submitted – April 22, 2013

RULE SUMMARY - Rule 74.11.1 regulates emissions of oxides of nitrogen (NOx) 

and carbon monoxide (CO) from natural gas fired water heaters, boilers, steam 

generators, and process heaters. Changes from the approved SIP rule include:

1. Revised the applicability of the rule to specify that the rule applies to 

natural gas-fired units.

2. Revised the applicability of the rule to only cover units with heat input 

capacity greater than or equal to 75,000 BTU/hr and less than or equal to 

1,000,000 BTU/hr. The rule covered units with heat input capacity greater 

than or equal to 75,000 BTU/hr and less than or equal to 2,000,000 BTU/hr 

until January 1, 2013. Beginning in January 1, 2013, units with heat input 

capacity equal to or greater than 1,000,000 BTU/hr and less than or equal 

to 2,000,000 BTU/hr will be regulated in the revised Rule 74.15.1. 

3. Lowered the NOx limit for new units with a heat input capacity of greater 

than or equal to 75,000 BTU/hr and less than or equal to 400,000 BTU/hr

to 14 nanograms per joule of heat output or 20 parts per million. This goes 

into effect January 1, 2014. Units specifically designed to heat swimming 

pools, hot tubs, and spas have a separate limit of 40 nanograms per joule 

of heat output or 55 parts per million.

4. Lowered the NOx limits for new units with a heat input capacity of greater 

than 400,000 BTU/hr and less than 1,000,000 BTU/hr to 20 ppm.

5. Revised the certification requirement to allow South Coast Air Quality 

Management District certification in accordance with SCAQMD Rule 

1146.2 to qualify for use in Ventura County.

6. Added the date of manufacture as information required in identifying 

complying water heaters.

7. Added a definition for “new unit,” specifying applicability to various sections 

depending on sold/sale/install date.
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EVALUATION CRITERIA - The following criteria were used to evaluate the 

submitted rule. 

1. Enforceability - The Bluebook (Issues Relating to VOC Regulation 

Cutpoints, Deficiencies, and Deviations, EPA, May 25, 1988) and the Little 

Bluebook (Guidance Document for Correcting Common VOC & Other Rule 

Deficiencies, EPA Region 9, August 21, 2001) were used to help evaluate 

compliance with the CAA §110(a)(2)(A) requirement for enforceability. 

2. Stringency - EPA’s Alternative Control Technique Document (ACT) titled, 

“NOx Emissions from Industrial/Commercial/Institutional (ICI) Boilers” (EPA453/R-94-022, March 1994), CARB’s RACT/BARCT guidance titled, 

“Industrial, Institutional, and Commercial Boilers, Steam Generators, and 

Process Heaters” (July 18, 1991), and other state and local rules for this 

category were used to help evaluate stringency. Generally, SIP rules are 

evaluated for RACT requirements of CAA §182(b)(2) and §182(f). 

3. SIP Relaxation - CAA §110(l) prohibits EPA from approving any SIP revision 

that would interfere with any applicable requirement concerning attainment 

and reasonable further progress (RFP) or any other applicable requirement 

of the CAA. In addition, CAA §193 prohibits the modification of any SIPapproved control requirement in effect before November 15, 1990, in a 

nonattainment area.

EPA EVALUATION - A summary of our evaluation of the three criteria follows.

1. The rule requirements and applicability are clear, and the monitoring, 

recordkeeping, reporting and other provisions sufficiently ensure that 

affected sources and regulators can evaluate and determine compliance 

with Rule 74.11.1 consistently. 

2. The submitted rule is as stringent as other California District rules for this 

category, including South Coast AQMD Rule 1146.2, Sacramento 

Metropolitan AQMD Rule 414, and Bay Area AQMD Rule 9-6, and it is more 

stringent than CARB’s RACT/BARCT guidance. As a result, we have 

determined that this rule fulfills stringency requirements. Rule 74.11.1 is not 

subject RACT since the rule is applicable to sources too small to exceed the 

major source threshold and there is no CTG for the source category.

3. The submitted rule’s applicability is narrowed after January 1, 2013. Instead 

of applying to water heaters, boilers, steam generators, and process heaters 

with a rated heat input capacity greater than 75,000 BTU/hr and less than or 

equal to 2,000,000 BTU/hr, the rule will only apply to units with rated heat 

input capacity greater than or equal to 75,000 BTU/hr and less than 

1,000,000 BTU/hr. This is not a SIP relaxation because the units formerly 

covered in the rule are now covered in the revised VCAPCD Rule 74.15.1 
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with lower emission limits for NOx. We are simultaneously acting on Rules 

74.11.1 and 74.15.1. We propose to determine that our approval of the 

submittal would comply with CAA §§110(l) and 193 because (1) the 

proposed SIP revision would not interfere with the on-going process for 

ensuring that requirements for RFP and attainment of the NAAQS are met, 

and (2) the emission limits in the submitted rule are more stringent than the 

existing SIP-approved control requirements that they would replace.

RULE DEFICIENCIES – We have identified no deficiencies with Rule 74.11.1 

sufficient for EPA to propose less than full approval.

ADDITIONAL RECOMMENDATIONS FOR THE NEXT RULE REVISION – At 

this time we have no additional recommendations for Rule 74.11.1.

EPA ACTION - The submitted Rule 74.11.1 strengthens the SIP, and the 

associated District staff report projects it will reduce NOx emissions by 11.3 

tons/year. The rule fulfills the relevant CAA §110 and part D requirements. EPA 

staff recommends a full approval of Rule 74.11.1 pursuant to CAA §110(k)(3) and 

§301(a). 

REFERENCES -

1. VCAPCD Rule 74.11.1, Large Water Heaters and Small Boilers, as 

amended June 26, 2012 and submitted to EPA on April 22, 2013.

2. VCAPCD Rule 74.11.1, Large Water Heaters and Small Boilers, as 

adopted on September 14, 1999, and approved into the SIP on December 

20, 2000 (65 FR 79752). 

3. “NOx Emissions from Industrial/Commercial/Institutional (ICI) Boilers,” 

EPA-453/R-94-022, March 1994. 

http://www.epa.gov/glo/SIPToolkit/ctg_act/199403_nox_epa453_r-94-

022_ici_boilers.pdf

4. “Issues Relating to VOC Regulation Cutpoints, Deficiencies, and 

Deviations,” (a.k.a., Bluebook) EPA OAQPS, May 25, 1988.

5. “Guidance Document for Correcting Common VOC & Other Rule 

Deficiencies,” (a.k.a., Little Bluebook), EPA Region 9, August 21, 2001 

(http://www.epa.gov/region09/air/sips/littlebluebook2001.pdf).

6. “Determination of Reasonably Available Control Technology and Best 

Available Retrofit Control Technology for Industrial, Institutional, and 

Commercial Boilers, Steam Generators, and Process Heaters,” CARB, July 

18, 1991 http://www.arb.ca.gov/ractbarc/boilers.pdf.