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Industrial/Commercial/Institutional (ICI) Boilers

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For state-specific information, including state agency points of contact, please use the ICI Boiler State Information tool.

This section covers environmental regulations and related topics, such as sustainability issues and news, associated with industrial/commercial/institutional (ICI) boilers:

  • Industrial boilers are used by heavy industry (e.g., paper products, chemical, food, and petroleum industries) to run processes or machinery or to produce heat or electricity. Most industrial boilers have a capacity between 10 and 250 million British thermal units (MMBtu/hr).

  • Commercial boilers are used by wholesale and retail trade, office buildings, hotels, restaurants, and airports to supply steam and hot water for space heating. Commercial boilers are generally smaller than the industrial units with heat input capacities generally below 10 MMBtu/hr.

  • Institutional boilers are used in establishments such as medical centers, universities, schools, government buildings, and military installations to provide steam, hot water, and/or electricity. Institutional boiler systems are used for heating with hot water or steam. A majority of these are located at educational facilities and have heat input capacities generally below 10 MMBtu/hr.

ICI boilers can use a number of different fuels including coal (bituminous, sub bituminous, anthracite, lignite), fuel oil, natural gas, biomass (wood residue, bagasse), liquefied petroleum gas, and a variety of process gases and waste materials. Each of these fuels has different combustion characteristics and produces distinct greenhouse gas emissions (GHG) emissions. Coal is the highest carbon dioxide (CO2) producer in ICI boilers with an average emission factor of 93.98 kg CO2/MMBtu; natural gas has the lowest emissions of CO2 from ICI boilers with an average emission factor of 53.06 kg CO2/MMBtu.

The ICI boiler information below is organized by the following topics:


Air Regulations

ICI boilers emit pollutants such as hazardous air pollutants (HAPs), particle pollution, and volatile organic compounds (VOC). These pollutants can contribute to health problems that may affect employees, residents, and the community. While Federal, state, local, and Tribal regulations limit the amount of emissions from ICI boilers, dangerous releases of HAPs can occur if an ICI boiler does not operate in compliance with regulations. More information on the health effects of pollutants emitted from ICI boilers.

EPA has promulgated New Source Performance Standards (NSPS) and proposed National Emission Standards for Hazardous Air Pollutants (NESHAP) for ICI boilers, which are discussed below.

New Source Performance Standards (NSPS)

Section 111 of the Clean Air Act, "Standards of Performance of New Stationary Sources," requires EPA to establish federal emission standards for source categories which cause or contribute significantly to air pollution. These standards are intended to promote use of the best air pollution control technologies, taking into account the cost of such technology and any other non-air quality, health, and environmental impact and energy requirements. These standards apply to sources which have been constructed or modified since the proposal of the standard. Since December 23, 1971, EPA has promulgated 88 such standards and associated test methods.

Generally, state and local air pollution control agencies are responsible for implementation, compliance assistance, and enforcement of the new source performance standards. EPA retains concurrent enforcement authority and is also available to provide technical assistance when a state or local agency seeks help. EPA also retains a few of the NSPS responsibilities -- such as the ability to approve alternative monitoring methods -- to maintain a minimum level of national consistency.

New Source Performance Standards for ICI boilers vary depending on the rated capacity of the boiler:

  • Standards for small boilers, defined as having a heat input capacity between 10 - 100 MMBtu/hr that were constructed, modified, or reconstructed after 9 June 1989

  • Standards for large boilers, defined as having a heat input capacity in excess of 100 MMBtu/hour that were constructed, modified, or reconstructed after 19 June 1984

Depending on the size of the unit and type of fuel combusted, the regulations have emission standards for sulfur dioxide (SO2), nitrogen's oxides (NOx) and particulate matter (PM). The NSPS also have requirements for monitoring and record keeping.

Subpart Dc--Standards of Performance for Small Industrial-Commercial-Institutional Steam Generating Units

This section applies to steam-generating boilers that were constructed, modified, or reconstructed after 9 June 1989 and have a design heat input capacity between 10 - 100 MMBtu/hr (2.9 - 29 megawatts). This standard sets emissions limits for SO2, and PM, and is found at 40 CFR 60.40(c).

Type of Standard Text of Standard
Applicability and delegation of authority §60.40c
Definitions. §60.41c
Standard for sulfur dioxide (SO2). §60.42c
Standard for particulate matter (PM). §60.43c
Compliance and performance test methods and procedures for sulfur dioxide. §60.44c
Compliance and performance test methods and procedures for particulate matter. §60.45c
Emission monitoring for sulfur dioxide. §60.46c
Emission monitoring for particulate matter. §60.47c
Reporting and recordkeeping requirements. §60.48c

Subpart Db--Standards of Performance for Large Industrial-Commercial-Institutional Steam Generating Units

This section applies to boilers that were constructed, modified, or reconstructed after 19 June 1984 and have a rated heat input capacity in excess of 100 million British thermal units per hour (MMBtu/hour) (29 megawatts). This standard sets emissions limits for SO2, PM, and NOx, and is found at 40 CFR 60.40(b).

Type of Standard Text of Standard
Applicability and delegation of authority. §60.40b
Definitions. §60.41b
Standard for sulfur dioxide (SO2). §60.42b
Standard for particulate matter (PM). §60.43b
Standard for nitrogen oxides (NO). §60.44b
Compliance and performance test methods and procedures for sulfur dioxide. §60.45b
Compliance and performance test methods and procedures for particulate matter and nitrogen oxides. §60.46b
Emission monitoring for sulfur dioxide. §60.47b
Emission monitoring for particulate matter and nitrogen oxides. §60.48b
Reporting and recordkeeping requirements. §60.49b

National Emission Standards for Hazardous Air Pollutants (NESHAP) for Major and Area Sources covering Industrial/Commercial/ Institutional Boilers and Process Heaters

National Emissions Standards for Hazardous Air Pollutants (NESHAPs) are emissions standards set by U.S. EPA for an air pollutant not covered by National Ambient Air Quality Standards (NAAQS) that may cause an increase in fatalities or in serious, irreversible, or incapacitating illness. The standards for a particular source category require the maximum degree of emission reduction that the EPA determines to be achievable, which is known as the Maximum Achievable Control Technology (MACT). These standards are authorized by Section 112 of the Clean Air Act and the regulations are published in 40 CFR Parts 61 and 63.

For the latest information on the Boiler NESHAP, see https://www.epa.gov/stationary-sources-air-pollution/compliance-industrial-commercial-and-institutional-area-source

NOx SIP Call

On September 24, 1998, EPA finalized a "Finding of Significant Contribution and Rulemaking for Certain States in the Ozone Transport Assessment Group Region for Purposes of Reducing Regional Transport of Ozone" (commonly known as the "NOx SIP Call") requiring 22 States and the District of Columbia to submit State Implementation Plans (SIPs) that address the regional transport of ground-level ozone. The rule requires emission reduction measures to be in place by May 1, 2003. These measures include controls on ozone precursors, such as NOx, emitted by fossil fuel-fired boilers and power generation units.

Boilers with a rated capacity over 250 million BTUs that are located in the eastern half of the US should be in contact with their state permitting agencies to see how this may apply.

More information is available from EPA on an information page on the NOx SIP Call.

Asbestos National Emission Standard for Hazardous Air Pollutants (NESHAP)

Asbestos is the name given to a group of naturally occurring minerals used in certain products to resist heat and corrosion. Common products that contain asbestos include, but are not limited, to pipe and boiler insulation, spray-on insulation, floor tiles, ceiling tiles, patching and joint compound, roofing material and transite shingles and siding.

The primary characteristic that makes asbestos a concern is its ability to separate into microscopic needle-like fibers. Once these fibers become airborne, (usually by disturbing the product in which they are contained), they can be inhaled into the lungs. The inhalation of asbestos fibers can cause serious diseases of the lungs and other organs that may not appear until years after the exposure has occurred.

Any facility that contains asbestos is subject to the Asbestos National Emission Standard for Hazardous Air Pollutants (NESHAP). The Asbestos NESHAP requires advanced notification (using an Intent to Renovate/Demolish Form) for projects exceeding established thresholds (based on linear or square feet of area disturbed) to ensure all precautions are being taken to minimize asbestos emissions. The rule covers work practices to be followed during demolition and renovation and other activities involving the processing, handling, and disposal of asbestos-containing material and specifies that no visible asbestos emissions can be discharged to the outside air during these activities.

In most states, EPA has delegated the authority to enforce the Asbestos NESHAP to the state environmental and/or labor agency. Find information for your state on the Asbestos State Resource Locator

More Resources for Air Regulations

Alternative Control Techniques Document-- NO Emissions from Industrial/Commercial/Institutional (ICI) Boilers (EPA-453/R-94-022). A report is issued by the Emission Standards Division, Office of Air Quality Planning and Standards, U.S. Environmental Protection Agency, to provide information to State and local air pollution control agencies.

Asbestos - EPA. Information from the Environmental Protection Agency concerning asbestos hazards, regulations, publications and resources.


Water Resources Protection

Combustion processes may generate wastewater associated with blowdown, condensate, and washout. Discharges of wastewater are regulated under the Clean Water Act (CWA). Facilities which discharge indirectly through a Publically Owned Treatment Works (POTW) are regulated under the Pretreatment Program, which insures that industrial facilities pretreat wastewater to remove pollutants which would affect the pollutant removal ability of the POTW. Facilities that discharge process or non-process wastewater directly to streams, rivers, etc. are regulated under the National Permit Discharge Elimination System (NPDES) and must obtain coverage under a General Permit or an Individual Permit.

In addition to compliance with rules covering wastewater generated by boilers, applicable facilities must be concerned with stormwater runoff.

Each of these topics is summarized below with links to related web pages and documents.

Indirect Discharge

Facilities that discharge wastewater into a sewer system that leads to a municipal treatment plant, also known as Publicly Owned Treatment Works (POTW) are indirect dischargers. The POTW typically is owned by the local municipality or a regional board or sewer authority.

In response to potential problems caused by industrial wastewater being discharged into POTW's, federal pretreatment regulations were developed. These regulations apply to all industrial and commercial facilities. Local POTW's with approved pretreatment programs have responsibility for enforcing pretreatment requirements. Otherwise, the rules are enforced by the state or EPA regional authority.

All indirect dischargers must meet national General Pretreatment Regulations (40 CFR 403). Additionally, certain types of facilities must also meet applicable categorical pretreatment standards. When a pollutant, discharged by an indirect discharging industry is not specifically limited by pretreatment standards, it is up to the state or local regulatory agency to develop local limits or to determine other appropriate means to control its discharge.

More information on discharges to POTW's:

EPA Pretreatment Program. Provides links to detailed information related to EPA's pretreatment program.

Envcap Wastewater State Locator (will link to new locator Mark is working on). Find state-specific information on permitting, technical resources and points of contact.

Direct Discharge

Facilities that discharge process wastewater or cooling water to surface waters are direct dischargers. Direct dischargers must obtain a permit under EPA's National Pollutant Discharge Elimination System (NPDES) program. A NPDES permit sets limits on the amount of specific pollutants that can be discharged to surface waters.

Some states offer general permits for non-contact process water that includes boiler blowdown (e.g., Arkansas ARG250000). The purpose of the general permit is to provide a streamlined NPDES permitting process for certain classes or categories of industrial point source discharges. Coverage under a NPDES general permit is unique in that a facility operates and discharges under the requirements of the applicable general permit rule rather than the requirements of an individual permit. Check with your state environmental agency to determine if a general permit is applicable to your facility.

More information on direct discharge NPDES permits:

EPA's National Pollutant Discharge Elimination System (NPDES). The site contains technical and regulatory information about the NPDES permit program. The NPDES Permits Program consists of a number of programs and initiatives.

Envcap Wastewater State Locator (will link to new locator Mark is working on). Find state-specific information on permitting, technical resources and points of contact.

Stormwater

Most industrial, commercial and institutional facilities must either obtain permit coverage under an individual or general permit or submit a no exposure certification form for stormwater associated with their operations. "No exposure" means all industrial materials and activities are protected by a storm resistant shelter to prevent exposure to rain, snow, snowmelt, and/or runoff.

Throughout most of the nation, U.S. EPA has delegated the stormwater program to the states to administer as they see fit, so long as minimum federal requirements are met. For more information on state stormwater rules see the Envcap Industrial Stormwater Resource Locator. The locator will help you find state-specific information on permitting, technical resources and points of contact.

More information on Stormwater:

EPA's Stormwater Program. Provides links to detailed information related to EPA's stormwater program.

Stormwater Discharges from Industrial Facilities. Explains the federal stormwater regulations for businesses and the permitting and waiver options available.

Industrial Stormwater Permit Guide. This tool explains federal stormwater regulations for business, and the options available for compliance.


Spill Prevention, Control and Counter Measures

EPA promulgated the Spill Prevention, Control and Counter Measures (SPCC) rule to reduce the risk of damaging our waterways from oil spills. These rules are applicable to a very wide range of facilities and operations, including fuel oil storage tanks for boilers. The rule requires specific facilities to prepare, amend, and implement SPCC Plans. The SPCC rule is part of the Oil Pollution Prevention regulation, which also includes the Facility Response Plan (FRP) rule.

An SPCC Plan is required for facilities which due to their location, could reasonably be expected to discharge oil to surface water or adjoining shorelines and have:

  • Total aboveground storage capacity of 1,320 gallons or more of oil (however, only containers or oil-containing equipment with a capacity equal to or greater than 55 gallons count toward the threshold); or

  • A total oil underground storage capacity of 42,000 gallons or more (however, underground storage tanks subject to regulation under RCRA [40 CFR 280 or 281] are not included); or

  • Been required by the EPA to prepare and implement an SPCC Plan.

The SPCC regulations require the facility owner/operator to prepare and implement an SPCC plan for their facility. This plan must be well thought out and prepared in accordance with good engineering practices. It must document the location of storage vessels, types of containment, dangers associated with a major release of material from the tanks, types of emergency equipment available at each site, and procedures for notifying the appropriate regulatory and emergency agencies.

More resources on SPCC:

Applicable rules: 40 CFR 112.


Pollution Prevention

Various programs and resources exist that are aimed at reducing the quantity of pollution, including greenhouse gas emissions (GHG), generated by operation of ICI boilers. Summaries are provided below with links to websites or full text documents.

  • EPA Clean Energy Programs. EPA's Clean Energy Programs are working with state policy makers, electric and gas utilities, energy customers, and other key stakeholders. By identifying, designing and implementing clean energy policy and technology solutions, we are delivering important environmental and economic benefits.

  • Available and Emerging Technologies for Reducing Greenhouse Gas Emissions from Industrial, Commercial, and Institutional Boilers. Provides information on control techniques and measures that are available to mitigate greenhouse gas (GHG) emissions from industrial, commercial, and institutional (ICI) boilers at this time (2010). The majority of the identified options focus on measures that are common from the perspective of applicability, availability, and owner/operator experience. Some options that may require project or site reconfiguration and process modifications, such as combined heat and power (CHP) and repowering, are also included in this section. Additional costs and complexities would need to be considered with these options.

  • Combined Heat and Power Partnership: A voluntary program seeking to reduce the environmental impact of power generation by promoting the use of CHP (cogeneration).

  • Boiler BMPs. Primarily focuses on boiler blowdown.

  • The American Boiler Manufacturers Association (ABMA) is the national, nonprofit trade association that represents the companies that design and build the systems that combust the fuels and generate the steam and hot water. See their Web site for technical information.

  • The Canadian Pollution Prevention Information Clearinghouse contains case studies highlighting pollution prevention at boilers.

Other ICI Boiler Resources

Small Business Ombudsman/Small Business Environmental Assistance Program (SBO/SBEAP) List of Contacts. Use this resource to find compliance assistance in your state. This EPA program was established to help small businesses comply with air quality regulations. However, many of these state technical assistance programs have expanded their air quality focus to provide technical assistance in other environmental areas.