Skip to Content
Questions or Comments: airperm@tceq.texas.gov

Outdated Standard Exemptions 98 - 107, January 8, 1980

Outdated Title 30 TAC 116 Standard Exemptions organized by exemption number and date.

Exemption

Clicking on a highlighted number below links you to the standard exemption.

98 | 99 | 100 | 101 | 102 | 103 | 104 | 105 | 106 | 107

98. Any pressure vessel storing carbon compounds composed only of carbon, hydrogen or oxygen provided that:

The pressure vessel vent is directed to an incinerator, boiler or other firebox having a stationary flue or a waste gas flare system that will operate with no visible emissions except as provided by the General Rules.

99. Any pressure vessel storing carbon compounds provided that:

The pressure vessel maintains working pressures sufficient at all times to prevent vapor or gas loss to the atmosphere.

100. Anhydrous ammonia storage tanks and distribution facilities in accordance with the following conditions:

  1. The tank is located at least 1/4 mile from any public building, public recreational area or any residence not owned and occupied by the company proposing to install the tank.
  2. The capacity of the storage tanks is 30,000 gallons or less.
  3. When transferring ammonia, all vapors shall be vented back to the host tank and never to the atmosphere.
  4. When relieving pressure from connectors and hoses, all vapors shall be bled into an adequate volume of water and never directly to the atmosphere.
  5. Before construction/installation of the facility begins, written site approval must be received from the Executive Director of the Texas Air Control Board.
  6. Before construction begins the facility must be registered with Form PI-6.

101. All aqueous fertilizer storage tanks.

102. Any fixed roof or floating roof storage tanks used to store alkanes, alkenes and aromatic compounds (composed of only hydrogen and carbon) crude oil, petroleum condensate, gasoline, naphtha, reformate or aviation fuel provided that:

  1. The tank is located at least 500 feet from any public building, public recreational area or any residence not owned and occupied by the person proposing to install the tank.
  2. The total emission of non-methane, non-ethane carbon compounds is less than 25 tons per year for each tank.
  3. The true vapor pressure of the compound to be stored is less than eleven (11.0) psia at the maximum storage temperature.
  4. For those compounds that have a true vapor pressure greater than 0.5 psia and less than 11.0 psia at the maximum storage temperature, the storage vessel shall be equipped with an internal floating roof with a single seal or an external floating roof with two seals.
  5. For any tank equipped with a floating roof the integrity of the floating roof seals shall be verified annually and records maintained to describe dates, seal integrity and corrective actions taken.
  6. The floating roof design shall incorporate sufficient flotation to conform to the requirements of API Code 650, Appendix C or and equivalent degree of flotation.
  7. Compounds with a true vapor pressure of 0.5 psia or less may be stored in a fixed roof tank which includes a submerged fill pipe or utilizes bottom loading.
  8. Except where a dark color is required for product heating, all uninsulated tank exterior surfaces exposed to the sun shall be painted chalk white.
  9. Compounds listed as hazardous air pollutants subject to National Emission Standards for Hazardous Air Pollutants (40 CFR 61) at the time the registration is received shall not be stored under this exemption.
  10. Emissions shall be calculated by methods outlined in Section 4.3 of EPA Publication AP-42, except that a seal factor (Ks) of 0.25 shall be used.
  11. Before construction begins, storage tanks of 25,000 gallons capacity or greater and located in a designated non-attainment area for photochemical oxidants shall be registered with Form PI-6. The exemption registration shall include the following supplemental information: (a) Table 1 of Form PI-2 listing all tanks and calculated emissions for each carbon compound in tons per year for each tank. (b) Table 7 of Form PI-2 - One table for each different tank design. (c) Where tank services are to be changed periodically the registration shall include for each tank a list of carbon compounds to be stored by name (Geneva system or other definitive nomenclature where possible), expected liquid volume annual throughput and physical property data for each carbon compound including vapor pressure and molecular weight.

103. Any new or modified production tank battery processing sweet crude oil and condensate provided that:

1. The plant is located at least 1/4 mile away from any public building, public recreational area or any residence not owned and occupied by the company proposing to install the tank or tank battery.
2. The total emissions of non-methane, non-ethane hydrocarbons are no more than 25 tons per year. Emissions may be determined as follows:

(a) The vents may be measured with an orifice well tester for a period of at least 24 hours. The average molecular weight and composition of the vent stream shall be determined by an analysis of the gas stream. The vent rates shall be measured when the oil or condensate production rate is at least 30 percent of the maximum production expected from the battery and the vent rates shall be corrected to the maximum expected production rate by multiplying by the appropriate factor as follows:

V max=V meas x (P max/P meas)

Where:
V max = maximum expected vent rate
V meas = measured vent rate
P max = maximum expected oil production rate
P meas = oil production rate during vent measurement

(b) The vents may be measured as in method(a); however, instead of analyzing the composition of the vent stream, the average molecular weight can be assumed to be 50 lb/lb mole and the composition to be 75 weight percent non-methane, non-ethane hydrocarbons.

(c) Emissions from tankage may be calculated by performing flash calculations based on analysis of the crude oil or condensate from the separator or heater treater plus appropriate temperature and pressure data.

(d) For batteries with no more than 250 barrels per day of production and liquid volatility no more than 5 lb. Reid, the following equation can be used to estimate the vent rate from a tank.

E = Wp M [0.0005 (P / (14.7 - P)) 0.68 D 1.73 + 0.00021 P Wo]

Where:
E = Emissions of non-methane, non-ethane hydrocarbons (tons/year).
M = Average molecular weight of vapors (as determined by analysis or assumed to be 50)
Wp = Weight fraction of non-methane, non-ethane hydrocarbons in the vent (as determined by analysis or assumed to be 0.75)
P = True vapor pressure at the storage temperature (psia)
D = Tank diameter (feet)
Wo = Tank throughput (thousand barrels per year)

Total emissions shall be determined by adding the calculated emissions from each tank. Emission from gun-barrel separators must be measured as required in either (a), (b) or (c).

104. Any new or modified production tank battery processing sour crude oil and condensate provided that:

(1) All requirements of Standard Exemption No. 103 for batteries handling sweet crude oil and condensate are satisfied.

(2) Total emission rate of hydrogen sulfide from operation of the battery (including upsets) does not exceed 4 pounds per hour.

(3) The total emission rate of hydrogen sulfide from the battery during normal operation or upsets determines the required height of emission for the vents. The venting of all produced gas due to loss of the gas sales line is considered to be an upset that must meet these requirements. No vent shall be less than 20 feet high. The following table determines the minimum height required for the vents. Stack heights for emission rates not covered can be determined by linear interpolation.

Total H2S Emissions, lb/hr Minimum Required Height of Stack, feet
0.27 20 feet
0.60 30 feet
1.15 40 feet
1.94 50 feet
3.00 60 feet
4.00 68 feet

(4) As an alternative to the requirements of (3), vents containing up to 50 pounds per hour of hydrogen sulfide may be burned in a smokeless flare that is equipped with a continuous pilot provided that the flare is at least 25 feet tall and meets the following requirements on heat release.

Q = 0.129 x 10 5 ((BTU/hr)/(lb/hr)) x E SO2

Where:
Q = minimum required heat release, BTU/hr
E SO2 = SO 2 emission, lb/hr

The total emission of sulfur dioxide form normal operation must be less than 25 tons per year.

105. Any cryogenic natural gas-liquids separation plant provided that:

  1. The plant is located at least 1/4 mile from any public building, public recreational area or any residence not owned and occupied by the company proposing to install the separation plant.
  2. Emissions of non-methane, non-ethane organic compounds, including fugitive losses, are less than 25 tons per year. Emissions from storage tanks and loading operations shall be calculated using methods and factors from AP-42.
  3. Emissions of sulfur dioxide are less than 25 tons per year and hydrogen sulfide emission are less than 4 pounds per hour. The height of the hydrogen sulfide emission point must meet condition (3) in Exemption No. 104 for tank batteries handling sour crude oil.
  4. Compressors associated with this facility shall meet the requirements of Exemption No. 6

106. Pathological incinerators with a capacity equal to or less than 200 pounds per hour provided that:

  1. The incinerator is a dual chamber design.
  2. Adequately sized burners are located in each chamber and the burners are automatically operated when the unit is charged with waste.
  3. Operating instructions are posted at the unit.
  4. The incinerator will operate with no visible emissions.
  5. Fuel shall be sweet natural gas or No. 2 fuel oil with less than 0.5% sulfur by weight.
  6. Before construction begins the facility must be registered with Form PI-6.

107. Boilers and heaters burning fuel oil with a sulfur content of 0.5% by weight or less or sweet natural gas and the maximum heat input is 10 X 10 6 BTU per hour or less.


Questions? We Can Help

If you have questions contact us.