United States Nuclear Regulatory Commission - Protecting People and the Environment

U.S. Nuclear Regulatory Commission

Access Control to High Radiation Areas at Nuclear Power Plants

HPPOS-234 PDR-9111210345

Title: Access Control to High Radiation Areas at Nuclear

Power Plants

See the memorandum from L. J. Cunningham to J. H. Joyner

(and others) dated August 2, 1991. A step-off pad (SOP) at

the access point to a high radiation area does not

constitute a barricade as required by Technical

Specifications. The health physics position was written in

the context of 10 CFR 20.203, but it also applies to "new"

10 CFR 20.1601.

Most Technical Specifications, in Section 6.12, "High

Radiation Area," require that each area in which the dose

rate is between 100 and 1000 mrem/hr be "barricaded and

conspicuously posted as a high radiation area ...." A

Region I licensee instituted a policy in which the

"barricade" consists of a SOP at the access to the high

radiation area. The area is roped off and posted but the

entry at the SOP is not roped off. The licensee maintained

that the SOP satisfies the barricading requirement in

Technical Specifications. This policy is used only in

situations where the area is a contamination area as well

as a high radiation area.

Technical Specifications with this barricade and posting

requirement provide a method for control of high radiation

areas that is an alternative to the method specified in 10

CFR 20.203 (c) (2) [or 10 CFR 20.1601 (a)]. Although not

explicitly stated, these controls are designed to prevent

inadvertent entry into the area. Controls specified in

Technical Specifications are intended to achieve the same

basic aim, namely prevention of inadvertent entry, but in a

different manner from that specified in Part 20. The

difference is to allow for the different nature of the

sources at nuclear power plants as well as the different

administrative controls and training found at such


Inadvertent entry is interpreted in this context to mean

entry by an individual who is not paying sufficient

attention to postings and who may walk into the high

radiation area unless his or her attention is drawn to

these postings. The assumption is that if an individual's

attention is drawn to the postings, that individual will

recognize their implications and take appropriate action.

A barricade is one mechanism to accomplish this purpose.

The dictionary defines a barricade as "any barrier that

obstructs passage." A SOP is not a barrier to movement

into the area and therefore does not qualify as a barricade

required by Technical Specifications. Implicit in the

requirement for the barricade is that the barricade can be

partially taken down for periods of access. This is

acceptable as long as the access point is attended by an

individual who will prevent inadvertent / authorized access

to the high radiation area.

Regulatory references: 10 CFR 20.203, 10 CFR 20.1601,

Technical Specifications

Subject codes: 4.1, 4.7

Applicability: Reactors

Page Last Reviewed/Updated Thursday, March 29, 2012