Access Controls and Shielding from Radioactive Hazards

DOE-STD-6003-96

Containment and isolation of liquid spills--Containment features instituted during the

design phase (e.g., curbing, dikes, reserve tankage, increased sump capacity) will

reduce contamination during the operational life of the facility and thus reduce the

contaminated surface area to be removed during decommissioning.

s. Preplaced blast holes--By incorporating blasting holes into monolithic concrete

structures during the construction of the facility before they have become radioactive,

the occupational exposure associated with their demolition is reduced.

6.2.2.2 Access Controls and Shielding from Radioactive Hazards

10 CFR 835 specifies that radiation exposure in controlled areas shall be kept below

regulatory limits and also ALARA through facility and equipment design and administrative

controls. The primary (preferred) methods to be used are physical design features such as con-

finement, ventilation, shielding, and remote operation. Administrative controls, including proce-

dural requirements, are to be used as secondary methods. Confinement and ventilation are

addressed in Section 6.2.1.4., access controls and radiation shielding are addressed below.

a. Access Controls

10 CFR 835 specifies that personnel access control shall be maintained for each radiolog-

ical area, with the degree of control to be commensurate with the potential or actual hazard.

One or more of the following methods is to be used.

1. Signs and barricades,

2. Control devices on entrances,

3. Conspicuous visual or audible alarms or both,

Locks on entrances, and

5. Administrative controls.

Items 1 and 5 are not a part of facility design and are not addressed below. For a High or

a Very High Radiation Area, one or more of the following seven features should be used for

each entrance or access point where radiation levels exist such that an individual could receive

an external dose to the whole body of 1 rem or more in any 1 h at 30 cm from the source or from

any surface through which the source radiation penetrates:

1. a control device that prevents entry to the area when high radiation levels exist or that

upon entry of a person causes the radiation level to be reduced to below the lower

limit for a High Radiation Area;

2. a device that functions automatically to prevent use or operation of the radiation

source or field while personnel are in the area;

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