Section 720. Insignificant activities

A. Insignificant activities include the following emissions units:

1. Gas flares or flares used solely to indicate danger to the public.

2. Ventilation systems not used to remove air contaminants generated by or released from specific units of equipment.

3. Air-conditioning units used for human comfort that do not have applicable requirements under Title VI of the Act.

4. Portable heaters which can reasonably be relocated through the manual labor of one person.

5. Portable electrical generators that can be moved by hand from one location to another.

6. Space heaters operating by direct heat or radiant heat transfer, or both.

7. Office activities and the equipment and implements used to carry out these activities, such as typewriters, printers, and pens.

8. Tobacco smoking rooms and areas.

9. Interior maintenance activities and the equipment and supplies used to carry out these activities, such as janitorial cleaning products and air fresheners, but not cleaning of production equipment.

10. Architectural maintenance and repair activities conducted to take care of the buildings and structures at the facility, including repainting, reroofing and sandblasting, where no structural repairs are made in conjunction with the installation of new or permanent facilities.

11. Repair or maintenance shop activities not related to the source's primary business activity, not including emissions from surface coating or degreasing (solvent metal cleaning) activities, and not otherwise triggering a permit modification.

12. Exterior maintenance activities conducted to take care of the grounds of the source, including lawn maintenance.

13. Internal combustion engines used for dry-cleaning and steam boilers.

14. Laundry activities, except for dry-cleaning and steam boilers.

15. Bathroom and locker room ventilation and maintenance.

16. Copying and duplication activities for internal use and support of office activities at the source.

17. Blueprint copiers and photographic processes used as an auxiliary to the principal equipment at the source.

18. Equipment used solely for the purpose of preparing food to be eaten on the premises of industrial and manufacturing operations.

19. Equipment used exclusively to slaughter animals, but not including other equipment at slaughterhouses, such as rendering cookers, boilers, heating plants, incinerators, and electrical power generating equipment.

20. Safety devices.

21. Air contaminant detectors and test equipment.

22. Brazing, soldering or welding equipment used as an auxiliary to the principal equipment at the source.

23. The engine of any vehicle, including but not limited to any marine vessel, any vehicle running upon rails or tracks, any motor vehicle, any forklift, any tractor, or any mobile construction equipment, including any auxiliary engine that provides cooling or refrigeration of the vehicle.

24. Fugitive emissions related to movement of passenger vehicles, provided the emissions are not counted for applicability purposes and any required fugitive dust control plan or its equivalent is submitted.

25. Emergency road flares.

26. Firefighting equipment and the equipment used to train firefighters.

27. Fire suppression systems.

28. Laboratories used solely for the purpose of quality control or environmental compliance testing that are associated with manufacturing, production or other industrial or commercial facilities.

29. Laboratories in primary and secondary schools and in schools of higher education used for instructional purposes.

30. Bench-scale laboratory equipment used for physical or chemical analysis, but no lab fume hoods or vents.

31. Routine calibration and maintenance of laboratory equipment or other analytical instruments.

32. Air compressors and pumps (engines for these emissions units are covered separately under subdivision C 1 of this section).

33. Pneumatically operated equipment, including hand tools.

34. Emergency (backup) electrical generators at residential locations.

35. Dumpster.

36. Grinding or abrasive blasting for nondestructive testing of metals.

37. Dryers and distribution systems for instrument air.

38. Parts washer (water-based).

39. Electric or steam-heated drying ovens and autoclaves, but not the emissions from the articles or substances being processed in the ovens or autoclaves or the boilers delivering the steam.

40. Salt baths using nonvolatile salts that do not result in emissions of any regulated air pollutants.

41. Dispensing facilities for refueling diesel-powered vehicles or equipment, including any diesel fuel storage tank serving only such dispensing facility, to the extent that this activity is not regulated by § 111 or § 112 of the federal Clean Air Act.

42. Storage tanks, vessels, and containers holding or storing liquid substances that will not emit any volatile organic compound or hazardous air pollutant.

43. Storage tanks, reservoirs, and pumping and handling equipment of any size containing soaps, vegetable oil, grease, animal fat, and nonvolatile aqueous salt solutions, provided appropriate lids and covers are utilized.

44. Equipment used to mix and package soaps, vegetable oil, grease, animal fat, and nonvolatile aqueous salt solutions, provided appropriate lids and covers are utilized.

45. Laboratory analytical equipment and vents except at stationary sources primarily engaged in research and development.

46. Equipment used for quality control/assurance or inspection purposes, including sampling equipment used to withdraw materials for analysis.

47. Nonroutine clean out of tanks and equipment for the purposes of worker entry or in preparation for maintenance or decommissioning.

48. Sampling connections and systems used exclusively to withdraw materials for testing and analysis including air contaminant detectors and vent lines.

49. Vents from continuous emission monitors and other analyzers.

50. Maintenance activities such as hand-held or manually operated maintenance equipment, railroad track maintenance, repair and maintenance cleaning, and maintenance surface preparation activities.

51. Hand-held equipment for buffing, polishing, cutting, drilling, sawing, grinding, turning, or machining wood, metal, or plastic.

52. Carbon monoxide lasers used only on metals and other materials which do not use hazardous air pollutants in the process.

53. Hand-held applicator equipment for hot melt adhesives with no volatile organic compounds in the adhesive formulation.

54. Equipment used for surface coating, painting, dipping, or spraying operations, except those that emit volatile organic compounds or hazardous air pollutants.

55. Drop hammers or hydraulic presses for forging or metalworking.

56. Blacksmith forges.

57. Solvent storage cabinet (containers covered).

58. Cooling ponds.

59. Coal pile run-off ponds.

60. Mechanical drive or gear boxes.

61. Equipment for steam cleaning or brushing dust off equipment.

62. Repair of residential units.

63. Farm equipment, with the exception of grain elevators or combustion devices not already listed as insignificant activities.

64. Water tanks.

65. Hydroblasting.

66. Hydraulic and hydrostatic testing equipment.

67. Process raw water treatment (e.g., phosphate).

68. Process water filtration systems and demineralizers.

69. Demineralized water tanks and demineralizer vents.

70. Ozone generators.

71. Water cooling tower except for systems including contact process water or water treated with chromium-based chemicals.

72. Spill collection tanks.

73. Steam vents and leaks from boilers and steam distribution systems.

74. Boiler water treatment operations, except cooling towers and those involving use of hydrazine.

75. Oxygen scavenging (de-aeration) of water.

76. Herbicide mixing and application activities not involving herbicide manufacture.

77. Nonhazardous boiler cleaning solutions.

78. Portable or mobile containers.

79. Vent or exhaust system for:

a. Transformer vaults and buildings;

b. Electric motor and control panel vents; and

c. Deaerators and decarbonators.

80. Vents or stacks for sewer lines or enclosed areas required for safety or by code.

81. Pump seals.

82. Rupture discs for gas handling systems.

83. Molasses storage tanks.

84. Storage of substances in closed drums, barrels or bottles.

85. Purging of natural gas lines.

86. Natural gas pressure regulator vents, excluding venting at oil and gas production facilities.

87. Blanking, chopping, trimming, perforating, repacking, and inspecting in connection with plastics manufacturing processes.

88. Consumer use of paper trimmers/binders.

89. Laser trimmers using dust collection to prevent fugitive emissions.

90. Sealed batteries such as those used for emergency backup power supplies.

91. Batteries and battery charging stations, except at battery manufacturing plants.

92. Parking lot resurfacing.

93. Environmental chambers not using hazardous air pollutant gases.

94. Shock chambers.

95. Humidity chambers.

96. Solar simulators.

97. Relief valves, excluding air pollution equipment bypass valves.

98. Steam vents and safety relief valves.

99. Steam leaks.

100. Steam cleaning operations.

101. Steam sterilizers.

B. Insignificant activities include emissions units, other than those listed in subsection A of this section, with the following emissions levels:

1. Emissions units with uncontrolled emissions of less than five tons per year of nitrogen dioxide, sulfur dioxide, or particulate matter (PM₁₀). Particulate matter emissions shall be used to determine uncontrolled emissions for purposes of this subsection only if particulate matter (PM₁₀) emissions cannot be quantified in a manner acceptable to the board. If the particulate matter (PM₁₀) emissions for any unit can be quantified in a manner acceptable to the board, that unit shall be deemed insignificant for particulate matter;

2. Emissions units with uncontrolled emissions of less than five tons per year of volatile organic compounds;

3. Emissions units with uncontrolled emissions of less than five tons per year of carbon monoxide;

4. Emissions units with uncontrolled emissions of less than 0.6 tons per year of lead;

5. Emissions units with uncontrolled emissions of hazardous air pollutants at or below 1,000 pounds per year;

6. Emissions units with uncontrolled emissions of any pollutant regulated under subpart C of 40 CFR Part 68 if those emissions are below the accidental release threshold levels set forth at 40 CFR 68.130 or 1,000 pounds per year, whichever is less.

C. Insignificant activities include emissions units, other than those listed in subsection A or B of this section, with the following sizes or production rates:

1. Internal combustion engines used for standby service, including compressors and pumps used for emergency replacement and portable generators, as follows:

a. Engines burning diesel fuel (maximum 0.5% sulfur) with 259,000 Btu per hour input or less;

b. Engines burning gasoline with 18,200 Btu per hour input or less.

2. Fuel burning equipment or combustion units with heat input levels less than:

a. 10 million Btu per hour rated input, using natural gas;

b. 1 million Btu per hour rated input, using distillate oil (maximum 0.5% sulfur).

3. Reservoirs and storage tanks for lubricant or used oil with a capacity of less than 1,000 gallons.

4. Internal combustion powered generators used at a facility only when power is unavailable to the facility from the utility as follows:

a. Diesel-fueled turbine emergency generators of 780 horsepower or less;

b. Diesel-fueled reciprocating emergency generators of 645 horsepower or less;

c. Natural gas-fueled turbine emergency generators of 1,240 horsepower or less;

d. Natural gas-fueled reciprocating emergency generators of 840 horsepower or less;

e. Dual-fueled reciprocating emergency generators of 840 horsepower or less.

Historical Notes

Derived from Volume 12, Issue 25, eff. October 15, 1996; amended, Virginia Register Volume 17, Issue 04, eff. Jan. 1, 2001.

Statutory Authority

§ 10.1-1308 of the Code of Virginia.