Revision I 

October 1979 U.S. NUCLEAR REGULATORY COMMISSION

REGULATORY GUIDE 

OFFICE OF STANDARDS DEVELOPMENT 

REGULATORY GUIDE 8.21 

HEALTH PHYSICS SURVEYS FOR BYPRODUCT MATERIAL AT 

NRC-LICENSED PROCESSING AND MANUFACTURING PLANTS

A. INTRODUCTION 

Paragraph 20.201(b) of 10 CFR Part 20, "Standards for 

Protection Against Radiation," requires that each licensee 

make or cause to be made such surveys as may be necessary 

for him to comply with the regulations in Part 20. As used 

in Part 20, the term "survey" is defined as an evaluation of 

the radiation hazards incident to the production, use, re

lease, disposal, or presence of radioactive materials or other 

sources of radiation under a specific set of conditions. This 

guide identifies the types and frequencies of surveys that 

are acceptable to the NRC staff for use in plants licensed by 

the NRC for processing byproduct material or manufactur

ing such material for distribution. 1 

B. DISCUSSION 

Surveys are considered to be part of a comprehensive 

protection program established by the licensee according 

to the philosophy and principles of Regulatory Guide 8.10, 

"Operating Philosophy for Maintaining Occupational Radia

tion Exposures As Low As Is Reasonably Achievable." Prin

ciples, methods, and instrumentation for carrying out radia

tion and contamination surveys were developed early in the 

atomic energy program and have been discussed in reports 

of the National Council on Radiation Protection and Mea

surement (NCRP) (Refs. 1-3), the International Atomic 

Energy Agency (IAEA) (Refs. 4-8), and the International 

Commission on Radiological Protection (ICRP) (Ref. 9). 

The health physics literature contains abundant informa

tion for use in establishing radiation survey programs and 

selecting appropriate methods, procedures, and equipment 

for their implementation (Refs. 3, 5, and 6). 

Surveys2 are a necessary supplement to personnel moni

toring, which measures individual radiation exposures with 

devices worn by the workers (Refs. 3, 5, 6, 8, and 9). 

1

NRC-Uicensed processing and manufacturing plants are referred 

to in this guide as "manufacturing plants." 2 The word "survey," often used synonymously with "surveil

ance," "monitoring," or "area monitoring," is used in this guide 

to connote the personal Inspection of various locations in a facil

ity using radioactive materials, with or without accompanying 

measurements, to determine the effectiveness of measures to 

protect against radiation.

C. REGULATORY POSITION 

Methods and procedures in this guide are acceptable to 

the NRC staff for establishing acceptable survey programs 

in accordance with the as low as is reasonably achievable 

(ALARA) philosophy. Manufacturers licensed by the NRC 

should have a health physics staff capable of developing and 

implementing survey programs as described below. 

1. TYPES OF SURVEYS 

1.1 General Description 

Surveys performed in compliance with §20.201 of 10 

CFR Part 20 should include those necessary to evaluate 

external exposure to personnel, concentrations of airborne 

radioactive materials in the facility, surface contamination 

levels, and radioactive effluents from the facility. Environ

mental monitoring of effluents is beyond the scope of this 

guide .

3 

Radiation protection programs should include the types 

of surveys discussed below.. 

1.2 Surveys of External Radiation Exposure Levels in 

Restricted Areas 

Radiation safety personnel 4 should survey locations 

where individuals may be exposed to radiation intensities 

that might result in radiation doses in excess of 10 percent 

of the limits of paragraph 20.101(a) of 10 CFR Part 20 in 

any calendar quarter or where an individual is working with 

a source that could be used unshielded at any time to pro- * 

duce a gamma or beta dose rate exceeding 0.5 mrad/h at 

1 meter. 

0 

Lines indicate substantive changes from previous issue. 

3However, the radiation safety program should include surveys or 

records that indicate control of the quantities of radioactive material 

released in air and water to unrestricted areas, as required by 10 CFR 

Part 20. 

4Reference to radiation safety staff or personnel in this guide is 

not intended to indicate that such staff necessarily consists of more 

than one person designated as responsible for radiation safety. The 

size and qualifications of the staff depend on the scope and idnd of 

manufacturing activities involving radioactive materials.

USNRC REGULATORY GUIDES Comments should be sent to the Secretary of the Commission. 

U.S. Nuclear Regulatory Commission Washington, D.C. 20555, 

Regulatory Guides are Issued to describe and make available to the Attention: Docketing and Service Branci. 

public methods acceptable to the NRC staff of implementing 

specific parts of the Commission's regulations, to delineate tech- The guides are issued in the following ten broad divisions: 

niques used by the staff In evaluating specific problems or postu

ated accidents or to provide guidance to applicants. Regulato 1. Power Reactors 6. Products 

Guides are noi substitutes for regulations, and compliance with 2. Research and Test Reactors 7. Transportation 

them is not required. Methods and solutions different from those set 3. Fuels and Materials Facilities 8. Occupational Health 

out In the guides will be acceptable If they, provide a basis for the 4. Environmental and Siting 9. Antitrust and Financial Review 

findings requisite to the Issuance or continuance of a permit or 5. Materials and Plant Protection 10. General 

license by the Commission. Copies of Issued guides may be purchased at thecurrent Government 

Comments and suggestions for improvements In these guides are Printing Office price. A subscription service for future guides in spe

encouraged at all times, and guides will be revised,. as appropriate, cific divisions Is available through the Government Printing Office. 

to accommodate comments and to reflect new information or Information on the subscription service and current GPO prices may 

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ments received from the public and additional staff review. Washington, D.C. 20555, Attention: Publications Sales Manager.
Preoperational, routine, and special surveys of these 

areas should be performed by the radiation protection staff 

as described in Section C.2 of this guide. Results of these 

surveys should be recorded as described in Section C.3. 

In addition, workers should monitor themselves and their 

own individual activities if they are exposed to external 

radiation levels that could exceed any of the limits of para

graph 20.101(a). These surveys by workers should consist 

of periodic instrument surveys during work with radioactive 

materials. Workers should be properly trained to conduct 

such surveys. 

Surveys are not acceptable for routine compliance with 

the personnel monitoring requirements of §20.202. How

ever, in the event of accidental loss of personnel dosimetry 

data, e.g., as a result of losing the dosimeter or chemical 

or physical damage to the dosimeter, the best alternative 

means of estimating the exposure may be to use survey data 

in conjunction with any fixed station dosimeters, doses 

received by co-workers, and appropriate occupancy fac

tors. In such case, the estimate, including the survey data 

used, should be documented and retained indefinitely (see 

paragraph 20.401(c)(2)(ii)). Survey results supplement 

personnel monitoring, when it is required, and they should 

be reviewed carefully by the Radiation Safety Officer in 

conjunction with personnel monitoring records to identify 

potentially hazardous situations and to ensure that all per

sonnel are adequately monitored. 

1.3 Measurements of Radioactive Material Concentrations 

in Air 

The radiation safety staff should perform measure

ments of radioactive material concentrations in air, at 

frequencies specified in Section C.2 of this guide, for areas 

where radioactive materials are handled or processed in 

unencapsulated form and when operations could expose 

workers to the inhalation of quantities of radioactive mate

rial exceeding those specified in paragraph 20.103(b)(2). 

Special requirements for such monitoring may also be made 

a condition of the license. 

Air samples collected should be representative of the air 

in the workers' breathing zone. However, when obtaining 

representative samples from the breathing zone is not prac

ticable, the samples should be obtained from a location at 

which the radioactivity concentration in air is known to 

be greater than that of the workers' breathing zone. For 

example, samples taken outside the breathing zone are 

acceptable if the sampler head is located so that the concen

tration of radioactive material in air at the location of the 

sampler head is equal to or greater than the concentration 

in the breathing zone. 

When measuring the quantity of radioactive material 

deposited on or in an air sample filter, the radiation safety 

staff should include appropriate corrections for alpha or 

beta absorption by the filter media and by material col

lected on the filter whenever these corrections may change 

results more than 10 percent. Filter media used for the col

lection of alpha emitters should retain collected material

on the filter surface. Overestimates of the volume of air 

that has passed through the filter should be avoided by 

means of accurate calibration of the flow rate and by pre

venting or correcting for the loss of flow due to the accu

mulation of material on the filter. 

Breathing zone or general air sampling should be con

ducted while work is in progress unless the results of con

tinuous sampling verify that the concentration of radio

active material in the breathing zone is not likely to exceed 

25 percent of the values given in 10 CFR Part 20, Appen

dix B, Table I, Column 1. The use of personal (lapel) 

samplers is acceptable for continuous air sampling as long 

as airflow rates are adequate to detect 25 percent of the 

appropriate values in Table I of Appendix B. during the sam

pling period. The air sampling frequency, if not con

tinuous, and the times selected for sampling should be 

based on the nature of the manufacturing process involved 

and the probability that airborne radioactive material will 

be present. When assessing this probability is difficult, 

frequencies based on information given in Section C.2 and 

Table 1 of this guide are acceptable. 

An air monitors may be needed to provide a warningsignal 

that the concentration of airborne radioactivity has become 

unexpectedly high. For each room or area where radioactive 

material is handled, the licensee should perform an analysis 

to determine whether an air monitor is necessary. Each anal

ysis should be kept available for inspection. 6 An air moni

tor should be provided if the analysis indicates that it is 

likely that, in the absence of an appropriate air monitor 

alarm, accidental conditions could cause an intake of radio-I 

active material exceeding the intake that would result from 

inhaling such material for 40 hours at the concentrations 

specified in 10 CFR Part 20, Appendix B, Table I,Column 1.7 

Workers should recognize that the principal function of 

an air monitor is to alert personnel to take immediate 

action to protect themselves from exposure to the unex

pected release of airborne radioactive material. Inhalation 

exposures are in progress during the time between the re

lease of the radioactive material and the sounding of the 

alarm. Thus, every reasonable effort should be made to 

minimize this time period. In particular, the air inlet of the 

monitor should be located near the potential source of air

borne radionuclides, preferably between the source and the 

workers. The use of long tubing or piping leading to the in

let should be avoided because of the high probability of 

alarm delay due to radionuclide deposition on the interior 

$The term "air monitor" as used here refers to a device providing an air or particle collection system, a radiometric measurement sys

tem, a continuous recorder (when the monitor Is also to be used to | assess personnel exposures), a meter with preset alarm capability, 

and an audible-alarm system. 

6Applicants should provide either the name of the manufacturer 

and model number of the air monitor to be used, specifications forI 

the appropriate type of air monitor to be used, or a copy of the 

analysis that verifies that an air monitor is not required. 

7To determine the quantity of radioactive material associated 

with this 40-hour exposure, multiply the concentation value 

specified in Appendix B to 10 CFR Part 20 by 4.8 x lO ml.

8.21-2
walls of the tube or pipe. The dose to personnel may be 

reduced by selecting a low-activity-level setpoint for the 

alarm; however, this may result in false alarms that weaken 

the workers' confidence in the monitor. These alternatives 

should be balanced to maximize safety. 

The dose to personnel may also be reduced by providing 

a high flow rate of air through the detection chamber or 

filter. A device such as a limiting orifice that is intended 

to provide a constant flow rate should not be used with I an air monitor when it reduces the flow rate to a level in

adequate for sufficient warning of an accidental release. It 

is more important to maintain a high volume of air drawn 

through the filter, thus reducing the time of exposure be

fore the alarm by using a higher flow rate, than to measure 

the concentration accurately. However, it is also important 

that routine intermittent and continuous releases be moni

tored. 

1.4 Surface Contamination Surveys 

Routine monitoring for radioactive contamination that 

could be present on surfaces of floors, walls, laboratory 

furniture, and equipment is a necessary part of the survey 

program. Failure to control surface contamination may 

result in unnecessary external or internal exposure of per

sonnel to radiation. Although external radiation levels from 

radioactive contamination may at times be hazardous, the 

primary concern is to avoid internal exposure resulting 

from the intake of loose radioactive material by inhalation, 

ingestion, or skin absorption. Also of concern is limiting 

contamination to areas where it can be controlled and 

maintaining contamination levels low enough that leaks or 

failures in control equipment can be detected as early as 

practicable. 

1.4.1 Removable Contamination 

For the purpose of this guide, removable contamination 

is that fraction of the contamination present on a surface 

that can be transferred to a smear test paper by rubbing 

with moderate pressure. Considerable information is avail

able to aid radiation protection personnel in the selection 

and use of instruments for performing surface contamina

tion surveys appropriate to the radionuclides involved in 

manufacturing plants (Refs. 1-22). 

Methods and instruments used in surface contamination 

surveys should be sufficiently sensitive to detect the nu

clides being monitored. Also, uniform methods for collect

ing and analyzing smear samples should be used over ex

tended periods of time in order to evaluate trends. Count

ing equipment used to analyze radioactive contamination 

on smear samples should be properly calibrated and main

tained and should be capable of detecting the radiation 

from the smears. For example, smears containing low

energy radiation emitters (e.g., H-3, C-14, 1-125) should be 

analyzed with liquid scintillation or internal proportional 

counters. Check or calibration sources should be counted 

with each batch or daily workload of smear samples.

When contamination levels in restricted areas can poten

tially exceed 0.1 percent of the respective limits in line 2 

of Table 2, the collection of smear samples should gener

ally be preceded by a rapid overall survey with a portable, 

thin-window detector in order to: 

a. Ensure that gross contamination levels are not already 

too high for counting in sensitive equipment, 

b. Minimize the chance for inadvertent spread of con

tamination by the smear survey or other activities to be 

performed in the meantime, and 

c. Determine which areas require greater attention in 

smear testing. 

The instrument used should have a readout system with as 

short a time constant as appropriate for the type of radia

tion to be detected and should be equipped with earphones I 

or an external speaker system. 

A standardized method for smear testing of a relatively 

uniform area should be used to aid in comparing contami

nation at different times and places. A dry smear taken 

from an area of about 100 cm 2 is acceptable to indicate 

levels of removable contamination. 

A diagram of each routinely surveyed area should 

ordinarily be used for recording survey results. When appro

priate, the diagram may be supplemented by or replaced by 

a detailed list of items and equipment surveyed. This pro

cedure will provide radiation safety personnel with a meth

od for identifying trends as well as satisfying regulatory 

requirements for survey records. The surveyor will find it 

helpful to specify key locations on the survey diagram that 

are smear-tested at each survey, in addition to other areas 

to be smear-tested in particular surveys, and also to provide 

a space reminding the recorder to include: 

. a. Contamination levels converted to radioactivity units 

in terms of equivalent alpha, beta, or gamma emission per 

unit area, in units specified in 10 CFR Part 20, 

b. Make and model number of instruments used in the 

survey and in counting the smear samples or appropriate 

reference to information in the same set of available rec

ords, 

c. Disintegration rate of each sample, 

d. Background count, 

e. All counting times, and 

f. Name of the person making the evaluation and re

cording the results and date. 

Provision should also be made on the diagram for recording 

an instrument check with an appropriate check or calibra

tion source.

8.21-3
The surveys discussed above are regularly scheduled, 

conducted by radiation safety personnel, and recorded on the survey diagrams. In addition, whenever the manufac

turing process is such that excessive contamination could occur between surveys by radiation safety personnel, more frequent, informal radiation surveys should be conducted 

by the radiation workers themselves; they need not be 

recorded. For example, a contamination survey can be 

made by collecting a smear sample and holding it within a few mm of (but not touching) a thin (less than 2 mg/cm 2 ) end-window detector while the detector is in an area where 

radiation levels are less than about 0.05 mrem/h. At these 

levels, any appreciable surface contamination can be de

tected by simply holding the detector in a fixed position 

and moving the smear sample close to and away from the 

detector several times and noting the meter readings. This 

method may be used for the majority of radionuclides 

processed in manufacturing plants (excluding alpha and 

very low-energy beta emitters). 

Part 20 of 10 CFR does not specify limits for surface 

contamination. Each applicant should propose and justify what removable surface contamination limits will be allow

able before decontamination will be performed in each 

work area. These limits should be based on the types of 

work to be performed and the need to avoid transfer of 

significant amounts of contamination to unrestricted areas and to maintain exposures as low as is reasonably achieva

ble (ALARA). The contamination limits for restricted areas presented in Table 2 of this guide are the maximum that 

will be acceptable to the NRC staff. Limits established for a particular installation should generally be lower than 

those in Table 2 and should be ALARA for the particular 

operations involved. 

1.4.2 Fixed Contamination 

For the purpose of this guide, fixed contamination 

is defined as radioactivity remaining on a surface after 

repeated decontamination attempts fail to significantly 

reduce the' contamination level. Since most detectors 

respond to both removable and fixed contamination, 

limits should be based on total contamination. Total con tamination surveys, using instruments suitable for the 

radionuclides involved, should be conducted at least quar

terly and simultaneously with a removable contamination 

survey. The applicant may propose and justify what total 

contamination limits will be allowable for both restricted 

and in-plant unrestricted areas before decontamination will 

be performed. The limits appearing on line 2 of Table 2, 

multiplied by a factor of 5, are the maximum that will be 

acceptable to the NRC staff. Limits that are ALARA 

should be established and justified by each applicant. 

1.5 Protective Clothing and Equipment Contamination 

Surveys 

Individuals working in areas where a potential for skin or clothing contamination exists should be provided with 

suitable protective clothing. If respiratory protective equip

ment is needed to protect against inhalation of airborne 

radioactivity, the equipment should be used according to

the instructions in Regulatory Guide 8.15, "Acceptable 

Programs for Respiratory Protection." Section 20.103 of 

10 CFR Part 20 specifies monitoring requirements when 

protection factors are assumed to be provided by the use of 

respiratory protection devices. 

Potentially contaminated protective clothing and equip

ment should be surveyed, removed, and placed in suitable 

containers or lockers before the worker leaves the restricted 

area. Since airborne radioactivity from contaminated 

protective clothing is likely to be produced by dislodging 

any absorbed radioactive particles during removal, fixed 

station monitors should also be available in clothing change areas to survey clothing before it is removed whenever 

clothing contamination levels may exceed 10 percent of the 

limits on line 4 of Table 2. In addition, suitable areas should be provided for surveying protective clothing and 

equipment before storing them for further use or for 

decontamination and laundering. 

When protective clothing contamination levels exceed 

preselected limits, workers should be instructed to take care to avoid dispersal of contamination and to report the situa

tion to the Radiation Safety Office. A member of the radi

ation safety staff should then survey and supervise any nec essary decontamination or clothing disposal. The applicant 

should propose and justify protective clothing contamina

tion limits considered adequate for each restricted area. 

The limits given on line 4 of Table 2 are the maximum that 

will be acceptable to the NRC staff. 

Contamination levels observed and procedures followed 

for incidents requiring special surveys and decontamination 

should be recorded. The record should include the names of persons surveyed, a description of prior work activities, 

the probable causes, steps taken to reduce future incidence 

of contamination, times and dates, and the surveyor's sig

nature. This information may be entered in a logbook. Indi

vidual worker surveys of themselves need not be recorded 

unless the limits on line 3 of Table 2 are exceeded. However, 

the radiation safety staff should maintain daily surveillance 

to ensure that the workers continue their own personal con tamination surveys. Results of radiation safety surveillance 

should be recorded. 

In restricted areas with little potential for surface con tamination, personal clothing is often worn beneath protec

tive clothing. Such personal clothing should be surveyed by the wearer before he or she leaves the restricted area. (How

ever, this is neither practicable nor necessary for employees 

working with only submicrocurie quantities of tritium or carbon-14.) When personal clothing contamination levels 

exceed preselected limits, workers should be instructed to 

report the situation to the Radiation Safety Office. A mem ber of the radiation safety staff should then survey and 

supervise any necessary decontamination or clothing dis

posal. The applicant may propose and justify personal cloth

ing (total) contamination limits. The limits given on line 3 

of Table 2 are acceptable to the NRC staff and need not be 

justified by the applicant. Clothing contamination is assumed 

to be removable but may be measured by a portable end

window detector as total contamination for survey purposes.

8.21-4
Records should be maintained in the same manner as those 

for protective clothing contamination. 

For individuals whose work is conducted in restricted 

areas with a potential for high surface contamination levels, 

complete clothing changes are normally provided. In this 

case, personal clothing should be stored outside the restrict

ed area. Surveys of personal clothing are not necessary, pro

vided the area in which the clothing is stored is surveyed as 

discussed in Section C.1.4 of this guide and the survey 

results are below the limits adopted for in-plant unrestrict

ed areas. Particular attention should be paid to surveying 

the body, hair, bottoms of the shoes or feet, and the hands 

after removal of protective clothing and to washing before 

donning personal clothing. 

1.6 Personal Surveys 

Individuals whose duties require work in restricted areas 

where radioactive contamination of body surfaces is proba

ble should also survey all exposed areas of the body after 

showering and before donning personal clothing or leaving 

the restricted area. Workers should be required to report 

the detection of contamination on the body to the Radia

tion Safety Office. Decontamination attempts, under the 

direction of Radiation Safety Office personnel or a medical 

consultant, should be repeated until (a) such attempts 

cease to effect significant reductions or (b) such attempts 

threaten to damage the skin.8 When decontamination 

attempts are terminated, there should be no further con

cern if the residual contamination does not exceed pre

selected levels since the contamination would no longer 

present a significant ingestion hazard. Such levels should 

be proposed and justified by the applicant. If residual con

tamination exceeds the selected limits, the affected indi

vidual should be released but periodic surveys should be 

made until the limits are no longer exceeded. The resulting 

dose should be determined and entered in the individual's 

personnel dosimetry record. Complete records should be 

maintained of each incident of this nature. 

Since manufacturing plants often process large quantities 

of unencapsulated radioactive material, bioassay programs 

may be required. Acceptable features of such programs are 

published in Regulatory Guides 8.9, "Acceptable Concepts, 

Models, Equations, and Assumptions for a Bioassay Program," 

8.11, "Applications of Bioassay for Uranium," and 8.20, 

"Application of Bioassay for 1-125 and 1-131," or are issued 

by the License Management Branch. 

1.7 Surveys of Equipment Prior to Release to Unrestrict

ed Areas 

Surface contamination surveys should be conducted for 

both removable and fixed contamination before potentially 

contaminated equipment is released from restricted to un

restricted areas. If contamination is detected, decontamina

Ition procedures should be repeated until contamination 

8 Decontamination attempts without the licensee's medical con

sultant present should be restricted to washing with mild soap and 

water, or with soaps specifically manufactured for hand washing, or 

to decontamination procedures previously agreed upon by the 

medical consultant. If such attempts do not reduce the contamina

tion to acceptable levels, the aid of a physician should be obtained.

levels are ALARA or additional efforts do not significantly 

reduce contamination levels. The applicant may propose 

and justify total and removable contamination limits below 

which uncontrolled release of equipment is permitted. The 

limits given for unrestricted areas on line I of Table 2 are 

acceptable to the NRC staff and need not be justified by 

the applicant. 

1.8 Ingestion 

Although it is highly unlikely that significant internal 

exposures will result from ingesting drinking water near 

work areas (Ref. 4), any water fountains in areas where 

contamination of the fountains or water is possible should 

be smear-tested regularly, and the water should be sampled 

and analyzed at least quarterly. Also, surveillance should be 

included in the radiation safety program to ensure that 

workers observe rules to prevent ingestion of radionuclides, 

e.g., rules pertaining to eating, drinking, or smoking in work 

areas or while wearing potentially contaminated clothing, 

storing foods in work areas, or pipetting by mouth. 

1.9 Surveys of Packages Received and Packages Pre

pared for Shipment 

External radiation surveys and smear tests of external 

surfaces of packages received or packaged for shipment 

should be carried out near the receiving or packaging point 

to avoid unwarranted radiation exposures and inadvertent 

contamination of personnel or the facility. When many 

packages of a kind known to be generally free of contami

nation are received, smear testing of a suitable random sam

ple should be considered in cases where smear testing of a 

large number of packages could increase external exposure 

of personnel. Surveys and required labeling must comply 

with regulatory requirements (see §§20.205, 32.19, and 

32.70 through 32.74 of 10 CFR) and with specific license 

conditions. Delivery of packages within the plant should 

also be monitored when carried by personnel rather than 

mechanical conveyors. Surveys should be made to deter

mine when carts rather than hand carrying should be used. 

Packages containing significant amounts of radioactive mate

rials should not be surveyed or opened until the containers 

have been placed in the appropriate protective facility such 

as a radiological-type fume hood or hot cell. 

No packages should be released for shipment or transfer to 

other users unless contamination levels of internal sources 

or devices have been tested and certified to meet (a) the 

criteria of paragraph 35.14(b)(5) of 10 CFR for Group VI 

products or (b) license conditions for other products as 

provided in §35.14 or in the manufacturer's license. Also, 

no packages may be released for shipment or transfer when 

external radiation or surface contamination levels exceed 

limits set by the Department of Transportation in Title 49 

of the Code of Federal Regulations. External radiation and 

contamination levels should be maintained ALARA. 

1.10 Checks on Posting of Caution Signs, Labels, Signals, 

Controls, and Notices to Employees 

The radiation safety staff should perform surveillance at 

least weekly to ensure that signs, labels, signals, other access

8.21-5
controls, and required Notices to Employees, copies of 

licenses, and other items are properly posted, legible, and 

operative, as required by 10 CFR Part 19, "Notices, Instruc

tions and Reports to Workers; Inspections," and Part 20 or license conditions. Radiation alarm signals and access con

trols should be tested to verify that they will operate pro

perly under both the normal and abnormal conditions that 

might be expected to occur. Care should be taken to mini

mize exposure to personnel who are conducting the tests. 

Any signs, labels, or notices found to be missing should 

be promptly replaced. Temporary signs, signals, or barriers 

together with appropriate worker notification and instruc

tion may be used in the interim when items as specified in 

10 CFR Parts 19 and 20 are not available, but acceptable 

corrections should be provided as soon as practicable. 

1.11 Leak Tests of Sources 

Leak testing of sealed sources must be carried out in 

accordance with the terms and conditions of the manu

facturer's materials license. Also, as provided in para

graphs 35.14(b)(5) and 35.14(e)(1), sealed sources con

taining 

a. More than 100 microcuries of a byproduct mate

rial with a half-life of more than 30 days (except iridium

192 seeds encased in nylon ribbon) or 

b. More than 10 microcuries of an alpha emitter 

must be leak tested for contamination or leakage at inter

vals not to exceed 6 months unless a different interval is 

specified for a particular manufactured source under the 

provisions of paragraph 32.74(b). Further provisions and 

exceptions to leak-testing requirements are established in 

paragraphs 35.14(b) and 35.14(e)( ). 

1.12 Calibration of Radiation Safety Instruments 

Portable survey instruments should be placed on a rou

tine maintenance and calibration program that will ensure 

that properly calibrated and operable survey instruments are available at all times for use by the health physics 

staff. 

An adequate calibration of survey instruments cannot be 

performed solely with built-in check sources. Electronic 

calibrations that do not involve a source of radiation also 

do not determine the proper functioning and response of 

all components of an instrument. However, an initial cali

bration with a radiation source and periodic tests using 

electronic input signals may be considered adequate for 

high ranges that are not used routinely. 

Daily or other frequent checks of survey instruments 

should be supplemented every 6 months with a calibra

tion of each instrument at two points separated by at 

least 50 percent of each linear scale that is used routinely, 

or with a calibration at one point near the midpoint of each 

decade on logarithmic scales that are used routinely. Digital 

readout instruments with either manual or automatic scale 

switching should be calibrated as are linear readout instru

ments. Digital readout instruments without scale switching

should be calibrated as are logarithmic readout instru

ments. Survey instruments should also be calibrated follow

ing repair. A survey instrument may be considered properly 

calibrated when the instrument readings are within + 10 

percent of the calculated or known values for each point 

checked. Readings within + 20 percent are considered 

acceptable if a calibration chart or graph is prepared and 

attached to the instrument. 

1.13 Surveys of Protective Clothing Before and After 

Laundering 

All garments with contamination levels exceeding those 

given on line 3 of Table 2 should be either disposed of as 

radioactive waste or properly surveyed, packaged, and 

labeled and sent to a laundry licensed to process and handle 

radioactively contaminated clothing. 

Each garment returned from a licensed laundry, or a sample of garments that are returned within a single pack

age, should be monitored before use. If contaminationi 

levels on the garment exceed those given on line 4 of Table 

2, the garment should not be used. 

1.14 Ventilation Surveys 

Radiation safety, personnel should conduct surveys 

monthly (or more frequently) to determine the face veloc

ity of air at the entrance of radiological-type fume hoods 

in use to protect workers against the hazards from unencap

sulated radioactive materials. 9 Such surveys should be made 

by using a properly calibrated thermoanemometer, velom

eter, or a U-tube observation after the initial measurement 

of flow rate to determine whether the airflow has been re duced to unacceptable levels by filter loading or the mal

function of blowers, fans, etc. The minimum average face 

velocity for a fume hood with the sash in the operating 

position or for an opening in a special enclosure should be 

100 ft/min, as determined from at least five different 

measurement points. 

Corrective action should be taken as soon as possible 

when the face velocity is found to be deficient. Work 

should be terminated if the average face velocity falls below 

100 ft/min. 

In addition to these surveys, each enclosure should be 

equipped with a device that measures pressure drop across the hood filter. Workers should be instructed to maintain 

daily checks of these devices and to notify radiation safety 

personnel when the pressure drop exceeds a preset level. 

At least annually, or when changes occur that might 

affect airflow, a survey should be made to determine the 

number of air changes per hour provided by the ventilation 

system in each room in which work with unencapsulated 

radioactive materials is conducted. A minimum of six changes 

per hour should be provided. 

9

Where filtered exhausts are employed, devices such as U-tube 

manometers or the equivalent should be provided to indicate the 

pressure drop across the filters so that the filters may be changed I before becoming excessively plugged.

8.21-6
1. 15 Surveys of In-Plant Unrestricted Areas 

Unrestricted areas should be surveyed periodically to 

ensure that radiation and radioactive material are ade

quately confined in restricted areas, except in cases where 

these materials must be transported between areas. Such 

transportation should be surveyed or planned with the radi

ation safety staff. 

1.15.1 Surface Contamination Surveys 

Removable surface contamination surveys in unrestricted 

areas should be performed and recorded at frequencies 

consistent with the potential for spreading contamination 

but not less frequently than quarterly. With the exception 

of lunch rooms and snack bars, random smear testing of 

floors and furniture is adequate. In lunch rooms and snack 

bars, equipment should also be surveyed. If such surveys 

reveal that radioactive contamination is being transferred 

out of restricted areas, immediate corrective action should 

be taken to eliminate such transfers, and decontami

nation efforts in the unrestricted areas should be repeated 

until it is evident that subsequent efforts would not sig

nificantly reduce contamination levels. If contamination 

is found in unrestricted areas, surveys should be performed 

on a more frequent schedule as necessary until the source 

of contamination is ascertained and corrected. The appli

cant may propose contamination levels, following decon

tamination efforts described above, for in-plant unrestricted 

areas. The limits given on line 1 of Table 2 are acceptable 

to the NRC staff and need not be justified by the applicant. 

1.15.2 Radiation Surveys 

Radiation surveys in unrestricted areas should be per

formed and recorded at frequencies consistent with the 

types and quantities of materials in use but not less fre

quently than quarterly. These surveys should be made in areas adjacent to restricted areas and in all areas through 

which byproduct materials are transferred and temporar

ily stored before shipment. Dose rates in these areas should 

be evaluated to determine whether they comply with the 

requirements of § 20.105 of 10 CFR. 

1.16 Surveillance 

1.16.1 Surveillance by Individual Performing Surveys 

The term surveillance, as used in this section, refers 

to observations of radiological working conditions in re stricted areas made by the person who performs the routine 

radiation and contamination surveys. Such surveillance, one of the most important aspects of a radiation protection pro

gram, allows health physics personnel to acquire detailed 

knowledge of each operation in order to (a) identify ways 

of preventing or minimizing exposures, (b) select appro

priate times for making health physics measurements, and 

(c) adequately prepare for emergency conditions. Health 

physics personnel should be sufficiently familiar with each 

operation to explain it in detail, to describe potential haz

ards and the precautions taken to minimize exposures, and 

to discuss how this knowledge of the operation has influenced the selection of appropriate times for performing 

health physics measurements. 

1.16.2 Regular Inventory of Radioactive Materia4 Audit 

of Procedures, and Instruction of Personnel 

The surveillance program includes: 

a. Regular inventory of radioactive materials and their 

locations, 

b. Frequent audits of radiation safety procedures and 

the uses and amounts of material in process compared to 

licensed possession limits, and 

c. Discussions with personnel to ensure their continued 

awareness of safety procedures and the appropriateness of 

their instruction and training for the tasks they are per

forming. 

These surveillance activities may be conducted during 

the performance of other survey measurements or tests. 

The radiation safety staff should conduct surveillance in

spections in a manufacturing plant at least weekly. The 

surveillance should be performed at least annually by the 

Radiation Safety Officer in the presence of a management 

representative such-as the plant manager to provide manage

ment with an awareness of the nature and importance of 

activities conducted for personnel protection and plant 

safety. 

2. FREQUENCY OF SURVEYS 

The frequency of routine surveys depends on the nature, 

quantity, and use of radioactive materials, as well as the 

specific protective facilities, equipment, and procedures 

that are designed to protect the worker from external and 

internal exposure. 

Generally, surveys should be performed before radio

active materials are used in a new facility in order to estab

lish a baseline of background radiation levels and radio

activity from natural sources, structural components of the 

facility (including radon and thoron emanation rates and 

concentrations), and any already existing operations with 

radiation sources in nearby rooms or facilities. These base

line surveys should be performed under the various condi

tions of containment, shielding design, and process heat 

loads to be expected under manufacturing conditions. Sur

veys of simulated process operations with nonradioactive 

reagents or smaller amounts of radioactive material should 

also be performed where appropriate to establish the per

formance of protective equipment and procedures before 

full-scale production using any new or untested facilities or processes. 

Surveys should be repeated as soon as process operations 

begin with normal levels of radioactive material and with all 

potentially exposed workers present and carrying out their 

job functions. Surveys should also be conducted after any 

significant changes in the conditions that existed at the 

time of the most recent survey, including changes in the

8.21-7
quantities of radioactive material handled or in protective 

equipment and procedures. 

Routine and repetitive surveys are necessary to control 

the containment of radioactive materials within handling 

systems and to ensure the continued integrity of protective 

equipment and procedures. Surveys are also necessary for 

procedures in which sealed sources are handled outside 

shielded containers. For operations involving materials 

in gas, liquid, or finely divided forms, the survey program 

should be designed to monitor the continued adequacy of 

containment and control of the materials involved. 

The minimum acceptable frequencies of surveys for manu

facturing plants are given in Table 1. The NRC staff considers 

the frequencies established in Table I to meet the require

ments of §20.101 of 10 CFR. 

3. RECORDS OF SURVEYS 

Reference should be made to §§20.401 and 30.51 and 

Parts 31-35 of 10 CFR for recordkeeping requirements 

regarding surveys related to the receipt, use, packaging, 

transfer, export, and disposal of byproduct material. Sec

tion 20.401 requires that licensees maintain records in the 

same units used in Part 20. Thus, external exposure rates 

should be recorded in estimated maximum dose equivalent 

units to relevant parts of the body as specified in 10 CFR 

Part 20. Air concentration measurement results should be 

recorded in units of .LCi/ml, and surface contamination 

measurement results should be recorded in units of dpm/ 

100 cm2 , pCi/100 cm 2 , or pCi/cm 2 (or as in §20.5). SI 

unit conversions may be specified as part of the record.

Record retention requirements are given in the regula

tions cited above. Paragraph 20.401(c)(2) requires that sur

vey records be preserved for 2 years, except that records of 

air monitoring and (in the absence of personnel monitoring 

data) records of surveys t6 determine external radiation 

dose are to be maintained until the NRC authorizes their 

disposition. 

Records may be maintained in logbooks or on special 

forms as long as they are clear, legible, understandable, and 

authenticated by authorized personnel. The signature of the 

person making the record and the date of the signature should 

be on the same page as the record and should immediately 

follow each record entry. Either the original or a reproduced 

copy or microform (duly authenticated) may be maintained 

to meet the storage requirements of § 20.401. 

D. IMPLEMENTATION 

The purpose of this section is to provide information to 

applicants and licensees regarding the NRC staff's plans for 

using this regulatory guide. 

Except in those cases in which the applicant or licensee 

proposes an acceptable alternative method, the staff will 

use the methods described herein in evaluating an appli

cant's or licensee's capability for and performance in com

plying with specified portions of the Commission's regula

tions after November 15, 1979. 

If an applicant or licensee wishes to use the method 

described in this regulatory guide on or before Novem-I 

ber 15, 1979, the pertinent portions of the application or 

the licensee's performance will be evaluated on the basis 

of this guide.

8.21-8
REFERENCES*

1. National Commission on Radiological Protection 

(NCRP) Report No. 8, "Control and Removal of Radio

active Contamination in Laboratories," December 15, 

1951. 

2. NCRP Report No. 9, "Recommendations for Waste 

Disposal of Phosphorus-32 and Iodine-131 for Medi

cal Users," November 2, 1951. 

3. NCRP Report No. 10, "Radiological Monitoring 

Methods and Instruments," April 7, 1952. 

4. International Atomic Energy Agency (IAEA) Techni

cal Report Series No. 120, "Monitoring of Radioac

tive Contamination on Surfaces," 1970. 

5. IAEA Safety Series No. 38, "Radiation Protection 

Procedures," 1973. 

6. IAEA Safety Series No. 1, "Safe Handling of Radio

nuclides," 1973 Edition, Code of Practice Sponsored 

by the International Atomic Energy Agency (IAEA) 

and the World Health Organization (WHO), 1973. 

7. IAEA Technical Report Series No. 133, "Handbook 

on Calibration of Radiation Protection Monitoring 

Instruments," 1971. 

8. IAEA Safety Series No. 25, "Medical Supervision of 

Radiation Workers," sponsored jointly by IAEA, 

WHO, and ILO, 1968. 

9. International Commission on Radiological Protec

tion (ICRP) Publication 12, "General Principles of 

Monitoring for Radiation Protection of Workers," 

Pergamon Press, 1969. 

10. AAPM Monograph No. 1, "Biophysical Aspects of 

the Medical Use of Technetium-99m," J.G. Kereiakes 

and Karen R. Corey, Editors (available from American 

Association of Physicists in Medicine, Dr. James G. 

Kereiakes, E555 Medical Sciences Building, University 

of Cincinnati, Cincinnati, Ohio 45267), 1976. 

11. International Commission onRadiationUnitsandMeas

urements (ICRU) Report No. 12, "Certification of Stand

ardized Radioactive Sources," September 15, 1968. 

12. NCRP Report No. 57, "Instrumentation and Monitor

ing Methods for Radiation Protection," 1978. 

13. NCRP Report No. 58, "A Handbook of Radioactivity 

Measurement Procedures," 1978. 

14. C. B. Meinhold, "Facility Monitoring Programs, Tech

niques, and Problem Solving,"Health Physics Opeattion

al Monitoring, Vol. 1, C. A. Willis and J. S. Handloser, 

Eds., Gordon and Breach, New York, 1972, p. 363.

15. C. A. Willis, "Safe Specific Activity: A Useful Concept 

in Monitoring Areas Containing Activated Materials," 

Health Physics Operational Monitoring, Vol. 1, C. A. 

Willis and J. S. Handloser, Eds., Gordon and Breach, 

New York, 1972, p. 373. 

16. H. J. Deigl, "Guidelines for Determining Frequency 

of Wipe Surveys," Health Physics Operational Moni

toring, Vol. 1, C. A. Willis and J. S. Handloser, Eds., 

Gordon and Breach, New York, 1972, p. 385. 

17. R. C. Henle and P. E. Bramson, "Evaluation of 

Internally Deposited 2 4 1 Americium from Bioassay 

Data," Health Physics Operational Monitoring, Vol. 

1, C. A. Willis and J. S. Handloser, Eds., Gordon 

and Breach, New York, 1972, p. 731. 

18. P. G. Voilleque, "Calculation of Expected Urinary 

and Fecal Excretion Patterns Using the ICRP Task 

Force Group Report on the Human Respiratory 

Tract," Health Physics Operational Monitoring, 

Vol. 1, C. A. Willis and J. S. Handloser, Eds., Gordon 

and Breach, New York, 1972, p. 773. 

19. R. L. Kathren, "Instruments in the Field Use, Abuse, 

and Misuse," Health Physics Operational Monitoring, 

Vol. 2, C. A. Willis, and J. S. Handloser, Eds., Gordon 

and Breach, New York, 1972, p. 811. 

20. W. P. Howell and R. L. Kathren, "Calibration and 

Field Use of Ionization Chamber Survey Instru

ments," Health Physics Operational Monitoring, 

Vol. 2, C. A. Willis and J. S. Handloser, Eds., Gordon 

and Breach, New York, 1972, p. 925. 

21. A. Brodsky, N. Wald, R. E. Lee, J. Horm, and R. 

Caldwell, "Plutonium-Americium Contamination 

Aspects of a Dry Box Incident Involving Hand Ampu

tation," Health Physics Operational Monitoring, Vol. 

3, C. A. Willis and J. S. Handloser, Eds., Gordon and 

Breach, New York, 1972, p. 1601. 

22. F. E. Gallagher, A. N. Tschaeche, C. A. Willis, J. C. 

Evraets, and J. C. Rogers, "Progress on Surface Con

tamination Standards," Health Physics Operational 

Monitoring, Vol. 3, C. A. Willis and J. S. Handloser, 

Eds., Gordon and Breach, New York, 1972, p. 1767. 

IAEA reports may be obtained from UNIPUB, Inc., P.O. Box 433, 

New York, N.Y. 10016. 

ICRP reports may be obtained from Pergamon Press, Maxwell 

House, Fairview Park, Elmsford, New York 10523. 

ICRU reports may be obtained from the International Commission on Radiation Units and Measurements, P.O. Box 30165, Washington, 

D.C. 20014. 

NCRP reports may be obtained from NCRP Publications, P.O. 

Box 30175, Washington, D.C. 20014.

8.21-9
Radlonuclide Group 

H-3, C-14. F-I8,* K-42,* 

Cu-64,* Tc-99m,* In

113m*

TABLE 1 

ACCEPTABLE FREQUENCIES FOR SURVEYS 

Amounts (Curies) in Process at Any One Time or Placed into Process in Any 

3-Mo. Period Within Any Room Requiring Surveys

External Radiation Surveys 

(nuclides with asterisks only)*

Weekly 

If point source of ac

tivity could exceed 50 

mrad/h at I meter

Monthly 

If point source of ac

tivity could exceed 

0.5 mrad/h at I meter

Air Sampling"* Surface Contamination

Weekly Monthly Quarterly Weekly Monthly Quarterly

2 10

<10

<1 ý 100 > 10 < 100

<10

o0.1

<0.1 II: Br-82, Cr-51,* Fe-55, 

1-123,* Hg-197* 

Ill: S-35, Au-198, Ca-47, 

1-132, Ce-141, Mixed fis

sion products,* Sr-85, La

140, Nb-95, Zn-65, Co

58,* Fe-59,* Na-24,* Co

57,* Se-75,* Mo-99" 

IV: Hf-181, Pm-147, P-32,* 

Ba-140,* Th-234, Kr-85, 

Ir-192,* CI-36, Y-91, Ta

i82, Ca-45, Sr-89, Cs-137, 

Co-60,* Ce-144,* 1-126, Eu-154, 1-131.* 1-125,* 

Tm-170, Na-22,* Mn-54** 

Ag-li0m,* Hg-203.* Rn

222,* Sn-1 13" 

V: Tc-99, 1-129, Ru-106 

VI: Ra-223, Po-210. Th-227, 

Sr-90, Pb-210, Cm-242, 

U-233*

z 0.01 

<0. I

<0.01

> 0.001 

Z 10-4

<0.1

<0.01 

<0.001

> 10-4 

<0.001 

> 10-' < 10-4

lO-S > 10

< 10-3 Sm-147, Nd-144, Ra-226,* 

Cm-244, Ra-228, Pu-24j 

Am-243, Am-241,* Np

237, Ac-227, Th-230, Pu

242, Pu-238, Pu-240, Pu-. 

239, Th-228, Cf-252

> 10-s

>Z10 > I < 10

<I 

>0.1 > 0.01 

< 0.1

<I

<0.1 

<0.01 

<0.001 <10-1 2_> 0.01 >0.001I 

<0.01 

<10-1• > 0.001 > .10-' 

< 0.001 

<O-6 ?! 10-4 > !0

S10-4

> 10- 7 <10-8 1 0- > 10-6 

< 10- < tO- 5

<10-6

*Nuclides with asterisks are those more likely to require external radiation surveys. 

"**Assuming continuous sampling is unnecessary (see Section C. 1.3).

1:

P0 

0

VII: 

VIII:

I
TABLE 2 

RECOMMENDED ACTION LEVELS FOR REMOVABLE SURFACE CONTAMINATION 

IN MANUFACTURING PLANTS 

Type of Radioactive Materiala 

Alpha Emitters Low-Risk 

High Lower Beta or X-Ray Beta or X-Ray 

Toxicity Toxicity Emitters Emitters 

Type of Surface (PCi/cm2 ) (PCi/cm2 ) (pCi/cm 2 ) (PCi/cm 2 ) 

1. Unrestricted areasb 10-7 10" 10-6 10-6 

2. Restricted areasc 10 -4 10-3 103 10-2 

3. Personal clothing worn outside 10"7 10-7 10-6 10-6 

of restricted areas 

4. Protective clothing worn only in 10"5 10"- 10r4 10-4 

restricted areas 

aHigh toxicity alpha emitters include Am-243, Am-241, Np-237, Ac-227, Th-230, Pu-242, Pu-238, Pu-240, Pu-239, Th-228, and Cf-252. 

Lower toxicity alpha emitters include those having permissible concentrations in air greater than that for Ra-226 (s) in 10 CFR Part 20, Appen

dix B, Table I, Column 1. Beta or x-ray emitter values are applicable for all beta or x-ray emitters other than those considered low risk. Low

risk nuclides include those whose beta energies are less than 0.2 MeV, whose gamma or x-ray emission is less than 0.1 R/h at 1 meter per curie, 

and whose permissible concentration in air in 10 CFR Part 20, Appendix B, Table 1, is greater than 10-6 ACi/ml. 

bContamination limits for unrestricted (non-contamination-controlled) areas in this table are considered to be compatible in level of 

safety with those for release of facilities and equipment for unrestricted use, as given in Re ulatory Guide 1.86, "Termination of Operating 

Licenses for Nuclear Reactors," and in "Guidelines for Decontamination of Facilities and Equipment Prir to Release for Unrestricted Use 

or Termination of Licenses for Byproduct, Source, or Special Nuclear Material," which is available from the Division of Fuel Cycle and 

Material Safety, Office of Nuclear Material Safety and Safeguards, U.S. Nuclear Regulatory Commission, Washington, D.C. 20555. 

cAs adapted from Table I of Reference 4. Averaging is acceptable over inanimate areas of up to 300 cm2 or, for floors, walls, and ceiling, 

100 cm'. These limits are allowed only in those restricted areas where appropriate protective clothing is worn. 

Note on Units: The above units of pci/cm2 have been used in this table since they are consistent with units adopted as national standards 

in several other nations and the IAEA (see Reference 6); the units of pCi and cm are already used to express concentration in 10 CFR Part 

20, and they are readily convertible to SI units by the well-known relation; I pCi •04 = 3.? x dis/sec = 3.7 x 1.0 Becquere.s (Bq). They may 

also be easily converted to other Jrequently used units of radiation protection practice, i.e., disintegrations/minute per 100 cm 2 2.22 x 

10* x (activity expressed in p.Ci/cm ). 

Note on Skin Contamination: Skin contamination should always be kept ALARA. Exposed areas of the body of persons working with un

sealed radioactive materials should always be monitored and should be washed when any contamination is detected. It is important, how

ever, that contaminated skin should not be so treated or scrubbed that the chance of intake of radioactivity into the body is increased. See 

Section 1.6 of this guide.

8.21-11
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