July 18, 1997





MEMORANDUM

SUBJECT:  Subpart O - Ethylene Oxide Commercial Sterilization
          Plant Explosions

FROM:     John Seitz, Director
          OAQPS

TO:       See Addressees

     On June 13 and July 5 explosions occurred at two ethylene oxide plants,
one in Virginia and one in Massachusetts.  In addition, an explosion occurred
June 24 at a facility in Indiana where one worker was killed and 69 other
persons were injured.  The explosion at the Indiana facility is under
investigation by the Chemical Accident Investigation Team of the Chemical
Emergency Preparedness and Prevention Office (CEPPO) in conjunction with
Region 5 and the State Occupational Safety and Health Administration (OSHA).
Apparently, these facilities are not the only ones which have had explosions
since promulgation of Subpart O on December 6, 1994. While the causes of
these explosions are not yet precisely known, these facilities were
using combustion control units to control emissions.  It is possible
these units could be a factor in these incidents.  We alerted the Regional
Air Toxic Coordinators on July 16 of this situation. 

     I recommend the following immediate course of action.  Regional
Offices/States should inform all ethylene oxide facilities of the recent
incidents and the potential safety problem.  If possible, they should compile
the type of control units plants are using or installing to comply
with the standards and let us know as soon as possible.  As part of this
communication, we recommend you inform the facilities that if they have a
safety concern they may disconnect the control units immediately in the
short term.  Compliance with Subpart O is not required until December 8,
1997.  In the meantime, we will develop options to ensure that facilities
will not be required to operate combustion control units until EPA can
determine that it is safe to do so; such options could include modifying
the compliance date,  if necessary.   I do not want the Subpart O
December 8, 1997 compliance date potentially compromising safety.

     We will work with all stakeholders to share information about
the causes of these incidents, to resolve safety concerns and to enable
the plants to ultimately comply with the requirements of the standards.
Industry representatives will provide, within the next few days, a list of
facilities which have had explosions or difficulties operating new controls
systems.  I'll forward this information to you as soon as we receive it.
If you have any questions regarding the emissions requirements please call
David Markwordt, at 919-541-0837.   If you have any questions about the
accident investigations, please call Craig Matthiessen at 202-260-9781.

                              2


Addressees:

Sent by Electronic Mail

Regional Air Division Directors
Linda Murphy, Region I
Kathy Callahan, Region II
Judy Katz, Reigon III
Winston Smith, Region IV
David Kee, Region V
Allyn Davis, Region VI
William Spratlin, Region VII
Kerrigan Clough, Region VIII
David Howekamp, Region IX
Anita Frankel, Region X

Regional Air Toxics Contacts
Janet Bowen, Region I
Umesh Dholakia/YueOn Chiu, Region II
Dianne Walker/Alice Chow, Region III
Lee Page, Region IV
Bruce Varner, Region V
Belinda Breidenbach, OECA
Robert Todd/Mark Potts, Region VI
Richard Tripp, Region VII
Victoria Parker-Christensen/Ann-Marie Patrie/Heather Rooney
     Region VIII
Mae Wang/Nikole Reaksecker, Region IX
Doug Hardesty/Andrea Longhouse, Region X

cc: Mary Nichols
      Richard Wilson
      Lydia Wegman
      Julie Andresen