Cleaver-Brooks | Reference Center | EPA Compliance | Definitions


Area Source facility is one that emits less than 10 tons per year of any single air toxic and less than 25 tons per year of any combination of air toxics. Most boilers covered by the Area Source Rule are located at commercial and institutional facilities, with a smaller number in the industrial sector. Commercial boilers include those found in stores/malls, laundries, apartments, restaurants, and hotels/motels. Institutional boilers are found in many locations, including medical centers (hospitals, clinics, nursing homes), educational and religious facilities (schools, churches), amusement parks, and municipal buildings (courthouses, prisons). 

Boiler is an enclosed device using controlled flame combustion in which water is heated to recover thermal energy in the form of steam or hot water. Controlled flame combustion refers to a steady-state, or near steady-state, process wherein fuel and/or oxidizer feed rates are controlled. 

Gas-fired boiler is one that burn fuels, including: natural gas, process gas, landfill gas, coal-derived gas, refinery gas, hydrogen, or biogas, not combined with any solid fuels. If a unit burns liquid fuel (e.g., oil) only during periods of gas curtailment, gas supply emergencies, or periodic testing, it is considered a gas-fired boiler. Periodic burning of a liquid fuel shall not exceed a combined total of 48 hours during any calendar year in order to maintain status as a gas-fired boiler. A boiler must be individually metered for fuel quantity and run time if it uses a backup fuel that does not qualify as gas based on the above list. 

Limited-use boiler is a unit with a federally enforceable operating limit of less than 10 percent of an average annual capacity factor. 

Notification of Applicability is a form required by the EPA to denote if a facility is an Area Source or a Major Source. 

Notification of Compliance is a form to be submitted to the EPA indicating that a unit is adhering to the required standards for tune-ups, emission limits, and energy audits, as required. 

Major Source facility emits 10 or more tons per year of any single air toxic or 25 tons or more per year of any combination of air toxics. The majority of Major Source boilers and process heaters are located at industrial facilities, such as: refineries, chemical and manufacturing plants, and paper mills. They may also stand alone to provide heat for commercial facilities such as warehouses, or institutional facilities such as universities. 

Process heater is an enclosed device using controlled flame, and the unit’s primary purpose is to transfer the heat indirectly to a process material (liquid, gas, or solid) or to a heat transfer material for use in a process unit, instead of generating steam.Process heaters are devices in which the combustion gases do not come into direct contact with process materials. Process heaters do not include units used for comfort heat or space heat, food preparation for on-site consumption, or autoclaves. 

Qualified Energy Assessor is someone who has the background, experience and expertise to evaluate energy savings opportunities for the types of boiler/energy use systems located at a particular facility.  The energy assessor may either be a company employee or an outside specialist.  For more complicated boiler or energy use systems or facilities with multiple boilers, a group, such as a consulting firm or a company’s engineering staff, with the needed expertise, could perform the required engineering assessment. 

Record keeping is required under the EPA rules. Although the type of records may vary according to the fuel type, size, and age of a boiler, most facilities will be required to maintain the following: boiler tune-up logs, records of fuel types used by boiler each month, record of fuel analysis, corrective actions associated with boiler/control equipment, performance tests, and fuel switching records. Maintain records for 5 years. For the first 2 years, records must be kept on site or accessible from a central location by computer or other means of instant access. 

Seasonal boiler is a unit that undergoes a shutdown for at least 7 consecutive months every 12-month period.

Startup is the first-ever firing of fuel in a boiler or process heater for the purpose of supplying steam or heat for heating and/or producing electricity, or for any other purpose, or the firing of fuel in a boiler after shutdown even for any purpose. Startup ends when any of the steam or heat from the boiler or process heater is supplied for heating, and/or producing electricity, or for any other purpose.

Shutdown is the cessation of the operation of a boiler or process heater for any purpose. Shutdown begins either when none of the steam from the boiler is supplied for heating and/or producing electricity, or for any other purpose, or at the point of no fuel being fired in the boiler or process heater, whichever is earlier. Shutdown ends when there is no steam and no heat being supplied and no fuel being fired in the boiler or process heater. 

Temporary boiler is a unit used in place of another boiler while that unit is being replaced or repaired, usually for less than 12 months unless an extension is approved.

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