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

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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.

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                                                                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

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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

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