Airborne Radioactivity Monitoring

DOE-STD-1098-99

Radiological Control

Radiological Health Support Operations

June 2004

Swipe surveys for removable contamination should be recorded in units of disintegrations per minute per 100 cm2

(dpm/100 cm2). For swipe surveys of small items covering less than 100 cm2, the results should be recorded in units

of dpm per area swiped. If contamination levels exceed the range of the available count rate meters, the swipes

should be analyzed by holding an appropriate exposure rate meter within one half inch and the results should be

recorded in units of millirad or rad per hour.

Large area wipes are encouraged and should be used to supplement standard swipe techniques in areas generally

assumed not to be contaminated, such as entrances to radiological areas. If an evaluation indicates that an area

wiped is contaminated, a thorough contamination swipe survey should be performed.

Areas identified as either contaminated with, or having the potential for being contaminated with, highly radioactive

particles ("hot particles") should be surveyed using special swipe techniques to collect hot particles, such as tape

and large area wipes.

555 Airborne Radioactivity Monitoring

In addition to the requirements of Article 551, air monitoring programs should be established to ensure that airborne

radioactivity monitoring is performed at a frequency that is consistent with the existing and potential hazards and

activitie s planned in the area. Selection of air monitoring equipment should be based on the specific job being

monitored. Air monitoring equipment includes portable and fixed air sampling equipment and continuous air

monitors.

Air sampling equipment shall be used where an individual is likely to receive an annual exposure of 40 or more

Derived Air Concentration (DAC) hours [see 835.403(a)(1)]. This intake generally represents a committed effective

dose equivalent to an individual of approximately 100 millire m. Samples shall also be taken as necessary to

characterize the hazard in areas where respiratory protection devices have been prescribed for protection against

airborne radionuclides [see 835.403(a)(2)]. Air samples should be adequate to evaluate the concentrations of

airborne radioactive materials at the individual's work locations.

Real-time (or continuous) air monitors are used to provide early warning to individuals of events that could lead to

substantial unplanned exposures to airborne radioactivity. Such exposures could result from a breakdown of

engineered controls or improper establishment of boundaries during work that creates airborne radioactivity. Real-

time air monitoring as necessary to detect and provide warning of airborne radioactiv ity concentrations that warrant

immediate action to terminate inhalation of airborne radioactive material [see 835.403(b)].

Air sampling equipment should be positioned to measure air concentrations to which individuals are exposed. If

this cannot be achieved, a program of personal breathing-zone air sampling should be initiated.

Air monitoring equipment shall be routinely calibrated and maintained on an established frequency [see 835.401(b)].

Air monitoring equipment should be calibrated at leas t once each year. Continuous air monitors should be capable

of measuring 1 DAC when averaged over 8 hours (8 DAC-hours) under laboratory conditions.

Real-time air monitoring equipment required by Article 555.3 should have alarm capability and sufficient sensitivity

to alert individuals that immediate action is necessary to minimize or terminate inhalation exposures.

A technical basis document should be developed for the airborne radioactivity monitoring program. The technical

basis document should provide the basis for air monitor selection, placement, and operation.

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