oEPA United State* Environmental Protection Agency Off ice of Solid Waste and Emergency Response DIRECTIVE NUMBER: 9441.02(85) TITLE: Exclusion of Sodium Azide in Air Bag Canisters of Obsolete Automobile Hulks from RCRA Regulations APPROVAL DATE: i-ie-85 EFFECTIVE DATE: i-ie-85 ORIGINATING OFFICE: office of Solid Waste S FINAL D DRAFT LEVEL OF DRAFT DA — Signed by AA or OAA D B — Signed by Office Director DC — Review & Comment REFERENCE (other documents): OSWER OSWER OSWER VE DIRECTIVE DIRECTIVE Dl ------- 261 SUBPART A - GENERAL DOC: 9441.02(85) Key Words: Regulations: Subject: Addressee: Originator: Source Doc: Date: Summary: Exclusion, Commercial Chemical Products 40 CFR 261.33 Exclusion of Sodium Azide in Air Bag Canisters of Obsolete Automobile Hulks from RCRA Regulations Hershel Cutler, Executive Director, Institute of Scrap Iron and Steel, Inc., 1627 K Street, N.W., Washington, D.C. 20006 Jack W. McGraw, Acting Assistant Administrator #9441.02(85) 1-16-85 Automobile air bags inflate upon ignition when the solid propellant burns and produces nitrogen gas. The active ingredients in the air bag propellant cartridges are sodium azide and oxidizers. The gas is generated through the action of both materials. The sodium azide therefore would not be regulated under RCRA as a listed hazardous waste because the Agency regulates commercial chemicals which are pure or technical grade and formulation in which the chemical is the sole active ingredient. The sodium azide in air bags is not the sole active ingredient. The Agency has not established de minimis concentration levels of toxicants below which wastes listed under §261.33 would no longer be regulated as hazardous wastes. The Agency grants exemptions on a case-by-case basis in response to petitions. ------- 9441.02 (&5) JIM Mr. Hershel Cutler Executive Director Institute of Scrap Iron and Steel, Inc. 1627 K St., NW Washington, DC 20006 Dear Mr. Cutler: . Your letter dated December 10, 1984, was referred to my office for response. - You expressed concern about the hazards posed by air bags that contain sodium azide, particularly as it affects the recovery of ferrous scrap from recycled automobiles. The Department of Transportation addressed these issues in a study released July 11, 1984, called Final Regulatory Impact Analysis, Amendment to FMVSS »20B, Passenger Car Front Seat Occupant Protection that explored many issues related to the use of air bags. A NHTSA staff member provided EPA with a copy of the section that discusses sodium azide. Page 111-20 of that report explains that the gas generants consist mainly of sodium azide and oxidizers. Page 111-12 explains that upon ignition, the solid propellant begins to burn, producing nitrogen gas that inflates the air bag. Based on this analysis of the mechanics of air bag deployment, the sodium azide containing initiator would not be regulated as a commercial chemical product regulated by the hazardous waste regulations of the Environmental Protection Agency. EPA regulates commercial chemicals which are pure, or technical grade and formulations 'in which the chemical is the sole, active ingredient. Air baq propellant cartridges contain, as active ingredients, both sodium azide and oxidizers. The gas is generated through the action of both materials. Thus, the Resrource Conservation and Recovery Act would not define the sodium azide in air bag canisters of obsolete automobile hulks as a listed hazardous waste. The Agency has not established de minimis concentration levels of toxicants below which wastes listed under 5261.33 would cease to be regulated as hazardous wastes. Rather, exemptions are granted on a case-by-case basis in response to petitions. Again, the sodium azide that is in air bags would ------- not 09 suoject to RCRA regulation a* a hazardous wasta because it is not a sole active ingredient. ' EPA in preparing a new regulation that would regulate certain mixtures of commercial chemical products. Under such a regulation, it is conceivable that the propellant cartridges could be classified as a hazardous waste. However, as- wa now envision such a regulation, auto hulks contaminated with either sodium azide or the propellent cartridges would not be so classified. In addition, If the air bags are deployed within the auto, the sodium aside is destroyed and there would be no question of even the spent canisters alone being considered subject to regulation. If the canisters were reclaimed, they would also not be regulated. The only case which may be regulated would be canisters which are removed and disposed of, which appears to be an unlikely scenario at the present time. The DOT study on sodium azide propellants concluded that non-deployed inflator modules can be deployed, that an electrical- deployment system is available now, that technical inspections for non-deployed modules are available, that a new retrofit air bag system is easily removed (and should have reasonably high salvage value), and that about 0.1 pound of sodium azide per site would be landfilled each working day. This study used a conservative estimate for the amount of sodium azide expected in each car, and EPA does not believe this management of sodium azide' to be a problem at this tHe. Moreover, EPA understands that auto manufacturers have expressed an interest in providing incentives for removal and collection of air bag canisters, which would further reduce the environmental dispersion of sodium azide. DOT regulation of deployment of. inflator modules and reclamation of air baj canisters appears to pose no environmental concerns that EPA jurisdiction should address at this time. If you have any further questions, please contact Alan Corson or Irene Homer of my staff at (202) 382-4770 for assistance. Sincerely yours, Jack W. McGraw Acting Assistant Administrator bcc: Ruth Bell, OGC Joyce Dain, TSCA William Fanj , NHTSA ------- |