An official website of the United States government.

This is not the current EPA website. To navigate to the current EPA website, please go to This website is historical material reflecting the EPA website as it existed on January 19, 2021. This website is no longer updated and links to external websites and some internal pages may not work. More information »

Oklahoma SIP: OAC 252:100-37-15 to 252:100-37-16: Control of VOCs in Storage and Loading Operations

Regulatory Text: 
Oklahoma Administrative Code.  Title 252.  Department of Environmental Quality 

Chapter 100.  Air Pollution Control (OAC 252:100)


As adopted in Oklahoma Register June 1, 1999 (16 Ok Reg 1767) effective June 11, 1999.
Approved by EPA December 29, 2008 (73 FR 79400) effective February 27, 2009 (OKd06).

252:100-37-15.  Storage of VOCs, OKd06
252:100-37-16.  Loading of VOCs, OKd06

252:100-37-15.  Storage of VOCs

     (a)  Storage capacities greater than 40,000 gallons.  Each VOC storage vessel with a capacity of more than 40,000 gal (151 m3) shall be a pressure vessel capable of maintaining working pressures that prevent the loss of VOC to the atmosphere or shall be equipped with one of the following vapor-loss control devices.
          (1)  An external floating roof that consists of a pontoon type or double-deck type cover, or a fixed roof with an internal-floating cover.  The cover shall rest on the surface of the liquid contents at all times (i.e., off the leg supports), except during initial fill, when the storage vessel is completely emptied, or during refilling.  When the cover is resting on the leg supports, the process of filling, emptying, or refilling shall be continuous and shall be accomplished as rapidly as possible.  The floating roof shall be equipped with a closure seal, or seals, to close the space between the cover edge and vessel wall.  Floating roofs are not appropriate control devices if the VOCs have a vapor pressure of 11.1 psia (76.6 kPa) or greater under actual conditions.  All gauging and sampling devices shall be gas-tight except when gauging or sampling is taking place.
          (2)  A vapor-recovery system that consists of a vapor-gathering system capable of collecting 85 percent or more of the uncontrolled VOCs that would otherwise be emitted to the atmosphere and a vapor-disposal system capable of processing these VOCs to prevent their emission to the atmosphere.  All vessel gauging and sampling devices shall be gas-tight except when gauging or sampling is taking place.
          (3)  Other equipment or methods that are of equal efficiency for purposes of air pollution control may be used when approved by the Division Director prior to installation.

     (b)  Storage capacities of 400 gallons and greater.  Each VOC storage vessel with a capacity of 400 gal (1.5 m3) or more shall be equipped with a permanent submerged fill pipe or a vapor-recovery system as required in 252:100-37-15(a)(2).

     (c)  Exemptions.  VOC storage vessels that are subject to equipment standards (e.g., a fixed roof in combination with an internal floating cover, an external floating roof, or a closed vent system and control device) in 40 CFR 60 Subparts K, Ka, or Kb are exempt from the requirements of 252:100-37-15(a) and (b).

252:100-37-16.  Loading of VOCs

     (a)  Loading facilities with throughput greater than 40,000 gallons/day.  Each VOC loading facility with a throughput greater than 40,000 gal/d (151,416 l/d) from its aggregate loading pipes shall be equipped with a vapor-collection and disposal system unless all tank trucks or trailers are bottom loaded with hatches closed.
          (1)  Vapor-collection and disposal system.
               (A)  Vapor-collection portion of the system.
                    (i)  When loading VOCs through the hatches of a tank truck or trailer, using a loading arm equipped with a vapor collecting adaptor, a pneumatic, hydraulic, or mechanical means shall be provided to ensure a vapor-tight seal between the adaptor and the hatch.
                    (ii)  When loading is effected through means other than hatches, all loading and vapor lines shall be equipped with fittings that make vapor-tight connections and which must be closed when disconnected or which close automatically when disconnected.
               (B)  Vapor-disposal portion of the system.  The vapor-disposal portion of the system shall consist of:
                    (i)  a vapor-liquid absorber system with a minimum recovery efficiency of 90 percent by weight of all the VOC vapors and gases entering such disposal system; or,
                    (ii)  a variable-vapor space tank, compressor, and fuel-gas system of sufficient capacity to receive all VOC vapors and gases displaced from the tank trucks and trailers being loaded.
          (2)  Prevention of VOC drainage.  A means shall be provided in either loading system specified in subsection (a) to prevent VOC drainage from the loading device when it is removed from any tank truck or trailer, or to accomplish complete drainage before removal.

     (b)  Loading facilities with throughput equal to or less than 40,000 gallons per day.
          (1)  Each loading pipe at a VOC loading facility with an aggregate throughput of 40,000 gal/d (151,416 l/d) or less shall be equipped with a system for submerged filling of tank trucks or trailers which is installed and operated to maintain a 97 percent submergence factor.
          (2)  Paragraph 252:100-37-16(b)(1) applies to any facility that loads VOCs into any tank truck or trailer with a capacity greater than 200 gal (757 l) which is designed for transporting VOCs.

     (c)  Exemptions.  Loading facilities subject to the requirements of 40 CFR 60 Subpart XX or 40 CFR 63 Subpart R are exempt from the requirements of 252:100-37-16(a) and (b).