Enforcement Policy For Hot Particle Exposure - Answers to Three Questions
HPPOS-246 PDR-9111220096
Title: Enforcement Policy For Hot Particle Exposure -
Answers to Three Questions
See the memorandum from L. J. Cunningham to J. H. Joyner
(and others) dated November 3, 1990. This memo notes that
IE Information Notice No. 90-48 states what NRC will do,
not what licensees are required to do, in assessing the
dose from hot particle exposures. The enforcement policy
does not require any licensee to change any procedure, and
the existing flexibility in determining compliance with
dose limits in 10 CFR 20 has not been eliminated as a
result of this policy. The dose to be recorded on NRC Form
5 (or equivalent) is the dose calculated to determine
compliance with the relevant Part 20 limit. The health
physics position was written in the context of 10 CFR
20.101, but it also applies to "new" 10 CFR 20.1201.
IE Information Notice 90-48, "Enforcement Policy for Hot
Particle Exposures," dated August 2, 1990, was sent to all
power reactor licensees. Since that time, nearly everyone
who has telephoned the NRR technical contacts about this
policy has asked if licensees are required to change any of
their procedures as a result of this policy. Also,
attendees at the Edison Electric Institute (EEI) Health
Physics Group meeting in Long Beach asked if, as a result
of this policy, existing flexibility in determining
compliance with the Part 20 limits has been eliminated.
The answer to the first question is no; the enforcement
policy does not require any licensee to change any
procedure. The enforcement policy states what the NRC will
do, not what licensees are required to do. This question
arose primarily because of the statement in the policy that
"In determining whether a hot particle exposure has
exceeded the limits of 10 CFR 20.101 [or 10 CFR 20.1201],
... hot particle exposures will not be added to skin doses
from sources other than hot particles...." Licensees, who
have been adding hot particle exposures to other skin
doses, asked if they needed to change their procedures for
recording skin doses. They were assured that they did not
need to change, but that the NRC would follow this policy
in determining whether or not an overexposure had occurred.
However, because of this statement in the policy, any
licensee who chooses to change record-keeping procedures so
as not to add hot particle exposures to other exposures is
free to do so.
The answer to the second question is also no; existing
flexibility in determining compliance with the Part 20 dose
limits has not been eliminated as a result of the policy.
This question arose primarily as a result of the statement
in the policy, taken from NCRP Report No. 106, that "...
the hot particle will be assumed to have been in contact
with the skin." However, this statement applies to use of
the policy after it has been determined that there has been
an overexposure. It does not have to be applied in the
determination of compliance or non-compliance with the dose
limits in 10 CFR 20.101 [or 10 CFR 20.1201]. However, once
the NRC staff has been informed that there has been an
overexposure, the staff is to use the assumptions required
by the policy to determine whether a notice of violation
will be issued and, if so, what the severity level should
be.
The following example may help clarify the answer to the
second question. Assume a hot particle has been found on
the inside of an inner (modesty) garment of a worker. In
determining the skin dose [or shallow dose equivalent] for
comparison with the relevant Part 20 dose limit [see 10 CFR
20.1201], the licensee and the NRC staff need not assume
that the particle was on the skin during the period of the
exposure. As in the past, the particle may be assumed to
have been on the clothing where it was found and the dose
to the skin may be determined using reasonable time and
motion studies that take into account the movement of the
garment and particle relative to the skin. If the dose
determined using these assumptions is below the relevant
Part 20 limit [see 10 CFR 20.1201], the enforcement policy
need not be considered. However, if the dose exceeds the
limit, the enforcement policy, which is based on NCRP
Report No. 106, must be applied by the NRC staff. In
applying this policy to this example, it must be assumed
that the particle was on the skin during the entire period
of the exposure, because it cannot be shown that the
particle was never on the skin.
The above example also raises the question of what dose
should be recorded on NRC Form 5 (or equivalent). Since
Part 20 requirements are not changed by the enforcement
policy, the dose to be recorded is the dose calculated to
determine compliance with the relevant Part 20 limit.
However, licensees may, if they choose, add supplemental
information concerning methods and values used by NRC staff
in enforcement actions.
Regulatory references: 10 CFR 20.101, 10 CFR 20.1201
Subject codes: 2.1, 8.3, 12.7
Applicability: Reactors