Boilers at Area Sources
The EPA finalized changes to Clean Air Act standards for boilers Dec. 20, 2012. These standards included separate rules for boilers at area sources (minor sources of hazardous air pollutants), found in 40 CFR 63, subpart JJJJJJ, and for boilers at major sources, found in 40 CFR 63, subpart DDDDD. Rules for both area and major sources can be found at Regulatory Actions.
The compliance date for the area sources rule is Jan. 20, 2014.
Frequently Asked Questions
You are affected if your facility is an area source and your boiler burns:
- coal (including coal refuse, petroleum coke, or synthetic fuels derived from coal)
- oil or other liquid fuel (for boilers that burn primarily gas but infrequently burn oil, see below)
- biomass
- non-waste materials
The following types of boilers are not covered by the rule:
- gas-fired boilers (a boiler that primarily burns gas is still considered a gas-fired boiler even if it also burns oil or other liquid fuel during periods of gas curtailment, gas supply interruption, startups, or for periodic testing not to exceed 48 hours during any calendar year)
- boilers that burn solid waste (these boiler are subject to incinerator standards)
- hot water heaters
- waste heat boilers (heat recovery steam generators)
- temporary boilers
- residential boilers
- electric boilers
- electric utility steam generating units (EGUs)
Area sources are commercial (laundries, apartments, hotels), institutional (schools, churches, medical centers, municipal buildings), or industrial (manufacturing, refining, processing, mining) facilities that emit or have the potential to emit less than 10 tons per year of a single hazardous air pollutant, or less than 25 tons per year of combined hazardous air pollutants.
| Heat Capacity (BTU/hr) | Existing Coal Units | New Coal Units | Existing Oil Units | New Oil Units | Existing Biomass Units | New Biomass Units |
|---|---|---|---|---|---|---|
| ≥ 10 MM | Yes 1 | Yes 1 | No | Yes 1,2,3 | No | Yes 1,2 |
| < 10 MM | No | No | No | No | No | No |
1 Provided the boiler does not meet the definition of limited-use boiler
2 Provided the boiler does not meet the definition of seasonal boiler
3 Boilers combusting only oil containing £ 0.50 weight % sulfur or a mixture of 0.50 weight % sulfur oil with other fuels not subject to PM emission limit and do not use a post combustion technology (except a wet scrubber) are not subject to emission limits.
| Heat Capacity (BTU/hr) | Existing Coal Units | New Coal Units | Existing Oil Units | New Oil Units | Existing Biomass Units | New Biomass Units |
|---|---|---|---|---|---|---|
| ≥ 10 MM | Yes 1 | No | Yes 1 | No | Yes 1 | No |
| < 10 MM | No | No | No | No | No | No |
1 Provided the boiler does not meet the definition of limited-use boiler
| Heat Capacity (BTU/hr) | Existing Coal Units | New Coal Units | Existing Oil Units | New Oil Units | Existing Biomass Units | New Biomass Units | Existing Seasonal or Limited Use Units | New Seasonal or Limited Use Units |
|---|---|---|---|---|---|---|---|---|
| ≥ 10 MM | No | No | Yes 1 | Yes 1 | Yes | Yes | ||
| < 10 MM | Yes 1 | Yes 1 | Yes 1 | Yes 1 | Yes | Yes | ||
| > 5 MM | Yes 1 | Yes 1 | ||||||
| ≤ 5 MM | Yes | Yes |
1 Provided the boiler does not meet the definition of limited-use boiler
2 Provided the boiler does not meet the definition of seasonal boiler
3 3 Boilers combusting only oil containing £ 0.50 weight % sulfur or a mixture of 0.50 weight % sulfur oil with other fuels not subject to PM emission limit and do not use a post combustion technology (except a wet scrubber) are not subject to emission limits.
4 Provided the boiler uses an oxygen trim system that maintains an optimum air-to-fuel ratio, otherwise tune-ups required biennially
Yes. A tune-up may be conducted early as long as the tune-up included all elements of the tune-up specified in the rule. In addition, the next tune-up is due no later than 25 months or 61 months, as applicable, after the date of the early tune-up.
No. If a boiler is not operating on the required date for a tune-up, the tune-up is required within 30 days of start-up.
There are more than 183,000 area source boilers used to generate heat in the United States. The individual emissions from these units may be small, but the total emissions from all boilers is significant. Air pollution from boilers includes particulate matter (PM 2.5), carbon monoxide, hydrochloric acid, mercury (from coal-fired boilers), and trace amounts of other heavy metals. Health effects include a range of respiratory issues, especially asthma among children and seniors.