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Outdated Standard Exemptions 1-6, April 25, 1986

Outdated Title 30 TAC 116 Standard Exemptions organized by exemption number and date.


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

1 | 2 | 3 | 4 | 5 | 6

1. Any facility constructed and operated at a domestic residence for domestic use.

2. Dual-chambered incinerators with a burner in the secondary chamber that maintains a temperature of 1200 degrees F or higher in the secondary chamber and with a burning capacity equal to or less than 1000 pounds per hour for Type 0, Type I and Type 2 wastes only where:

Type 0 (Trash) wastes - Principal components are highly combustible waste, paper, wood, cardboard cartons, including up to 10% treated papers, plastic or rubber scraps. Moisture content less than or equal to 10%; incombustible solids less than or equal to 5% and

Type 1 (Rubbish) wastes - Principal components are trash, rags, wood scraps, garbage (animal and vegetable wastes) and combustible floor sweepings. Garbage content cannot exceed 20%. Moisture content less than or equal to 25%; incombustible solids less than or equal to 10%, and

Type 2 (Refuse) wastes - Principal components are trash and rubbish. Garbage content cannot exceed 50%. Moisture content less than or equal to 50%; incombustible solids less than or equal 7%;

and which meet the following conditions:

(a) Operating instructions shall be posted at the incinerator.
(b) Fuel for the incinerator shall be limited to sweet natural gas, liquid petroleum gas, No. 2 fuel oil with less than 0.5% sulfur by weight or electric power.
(c) There shall be no obstruction to stack flow, such as by rain caps, unless such devices are designed to automatically open when the incinerator is operated. Items such as properly installed and maintained spark arrestors are not considered obstructions.
(d) This facility shall be used solely for the disposal of waste materials generated on-site. Incinerators used in the processing or recovery of materials are not covered by this exemption. Heat recovery, where no auxiliary fuel is burned, is allowed by this exemption.
(e) For incineration of wastes containing pathological type materials, see Standard Exemption 90.

3. Combustion units designed and used exclusively for comfort heating purposes employing liquid petroleum gas, natural gas or solid wood as fuel. Combustion of bark chips, sawdust, wood chips, treated wood or wood contaminated with chemicals is not included.

4. Comfort air conditioning systems or comfort ventilating systems which are not used to remove air contaminants generated by or released from specific units of equipment.

5. Internal combustion (IC) engine driven compressors, IC engine driven electric generator sets and IC engine driven water pumps and equipment components for gas dehydration units, gas-oil separators, free water knockouts, iron sponge units, production tank batteries and natural gas liquids separation plants used only for emergency replacement or standby services provided that:

(a) There will be no increase in emissions resulting from the operation.
(b) If not previously permitted the emissions meet the applicable emission abatement and emission rate requirements of Standard Exemptions 6, 66 or 79.
(c) Registration requirements of Standard Exemptions 6 or 66 are met.
(d) Replacement of equipment components at permitted facilities must comply with permit amendment or permit revision procedures.

6. Gas or liquid fuel fired stationary internal combustion engines or gas turbines, provided that all proposed engines and turbines satisfy all the following conditions:

(a) Within 10 days after construction of the facility begins, it shall be registered with Form PI-7, including applicable information demonstrating compliance with (b) below and information concerning the air quality in the area of the proposed facility. [See (c) below]. Engines smaller than 240 horsepower (HP) need not be registered, but must meet all other conditions of this exemption.
(b) The emissions of nitrogen oxides (NO x) [(nitrogen oxide (NO) plus nitrogen dioxide (NO 2)] are no more than 5.0 grams per horsepower-hour (gr/HP-HR) for any such gas fired engine or turbine, or 11 gr/HP-HR for any such liquid fired engine or turbine where such are classified as follows:

  1. Manufactured new after September 23, 1982, and rated at 825 HP or more.
  2. Rebuilt, reconditioned and/or modified after September 23, 1982, where the cost of such rebuilding, reconditioning and/or modifications exceeds 50% of the cost of a new, similar or complete replacement engine or turbine and rated at 825 HP or more.
  3. Engines or turbines used for emergency, standby or temporary replacement purposes (provided that maximum annual operating hours of the substituted equipment do not exceed 10% of normal annual operating schedule of the primary equipment) shall be exempt from the gr/HP-HR emission limits specified above. Maintenance test running of these engines or turbines shall not exceed 52 hours per year.

Documentation of manufacturing date is required, as well as certification that the engine or turbine has not been rebuilt, reconditioned and/or modified after September 23, 1982. In addition, the owner or operator shall submit and implement monitoring and/or testing plans sufficient to demonstrate that the NO x emissions do not exceed the gr/HP-HR limitation specified above. Monitoring and testing results shall be made available to the agency upon request.

(c) There will not be violations of any National Ambient Air Quality Standard (NAAQS) in the area of the proposed facility. Compliance with this condition shall be demonstrated by one of the following three methods:

(1) Ambient sampling or dispersion modeling accomplished pursuant to guidance obtained from the Executive Director.

Unless otherwise documented by actual test data, the following NO 2/NO x ratios shall be used for modeling NO 2 NAAQS:

Device NOx Emis. Rate (Q) gm/hp-hr NO2/NOx Ratio
IC Engine Less than 2.0 0.4
IC Engine 2.0 thru 10.0 0.15 + (0.5/Q)
IC Engine Greater than 10.0 0.2
Turbines 0.25
IC Engine with catalytic converter 0.85

or (2) All existing and proposed engine and turbine exhausts are released to the atmosphere at a height at least twice the height of surrounding obstructions to wind flow. Buildings, open sided roofs, tanks, separators, heaters, covers and other type of structure are considered as obstructions to wind flow if the distance from the nearest point on the obstruction to the nearest exhaust stack is less than five times the lesser of the height, Hb, and the width, Wb, where:

Hb = maximum height of the obstruction and
Wb = projected width of obstruction = 2 square root of {(L x W)/(3.1416)}

L = length of obstruction
W = width of obstruction

or (3) The total emissions of NO x (NO plus NO 2) from all existing and proposed facilities on the property do not exceed the most restrictive of the following: (1) 250 tons per year, (2) the value (0.3125 D) tons per year, where D equals the shortest distance in feet from any existing or proposed stack to the nearest property line.