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196
RADIOLOGICAL CLEANUP OF ENEWETAK ATOLL
The individual was decontaminated if skin contamination exceeded 200
disintegrations per minute (dpm) alpha per 100 square centimeters at
contact, or 400 dpm beta per 15 square centimeters at 1 inch. Equipment
released to a clean area for any reason required decontamination if it
exceeded limits based on draft American National Standards Institute
(ANSI) Standard N328-1976, as amended by DOE-Nevada Operations
Office (DOE-NV), i.e.:
a. Alpha: 1000 dmp/100 square centimeters fixed, or 20 dpm/1!00 square
centimeters removable.
b. Beta: 5000 dpm/100 square centimeters fixed, or 200 dpm/100 square
centimeters removable.
c. Gamma: 15 wR/hr.
Because of the potential for contamination, a laundryfacility for cleaning
washable personnelprotective equipment wasbuilt at Lojwa. Thisfacility,
operated by the USAE undersupervision of the FRST, had holding tanks
and provisions for ait and waste water sampling. FCRR SOP 608-10,
Decontamination Laundry Procedures, 2 July 1978, provided detailed
guidance on the operation and monitoring ofthis facility.
Radiation measurement, in itself, does not reduce exposure or
contamination. Rather, it provides data which may be used to determine
the requirements for preventive or remedial action. Such measures
include monitoring, dosimetry, air sampling, and bioassay. Each is
discussed in the following paragraphs.
Monitoring of personnel, vehicles and equipment was
used to
determine the extent of decontamination required, if any, upon exit from
a controlled area as described above. Monitoring also was used to
document the clean status of equipment released for general use and
retrograded from the atoll.
Personnel dosimetry is the means by which the beta/gamma dose to
which an individual has been exposed may be determined. At Enewetak,
the primary dosimetric device—as prescribed by AR 40-14—wasthe film
badge, issued and evaluated by the U.S. Army Lexington-Blue Grass
Depot Activity (LBDA). The film badge program was administered in
accordance with AR 40-14, and the dosimetry results were recorded on DD
Form 1141. Initially, visitors to the atoll who toured radiologically controlled
islands were issued self-reading pocket dosimeters which could be
evaluated onatoll, instead of film badges which required weeksto process.
The high heat and humidity conditions at Enewetak, combined with
generally wet working conditions, damaged a considerable percentage of
the film badgesin the initial months of the project. Typically, this damage
was such that, if low doses had been received by the wearers, they would
have been obscured by the damage. Higher dosesstill would have been