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Radiation Protection


A computerized screening tool for evaluating radiationHelpradiationEnergy given off as either particles or rays. exposure from atmospheric releases of radionuclides. May be used for demonstrating compliance with some EPA and Nuclear Regulatory Commission regulations, including the National Emission Standards for Hazardous Air Pollutants (NESHAPs) in 40 CFR Part 61, Subpart H and Subpart I.

COMPLY-R is specified for showing compliance with NESHAPs Subpart B.

Version 1.7.1 has been tested on systems running Windows 7, 8, 8.1, and 10.  A local hard drive or other local storage is required. Version 1.7.1 may not be compatible with all printers. Users encountering difficulty printing should write the output to a file rather than direct to a printer.

On this page:


COMPLY, Version 1.7.1(1 pg, 454 K)

Guide for Determining Compliance With the Clean Air Act Standards for Radionuclide Emissions From NRC-Licensed and Non-DOE Federal Facilities: Revision 2

User's Guide for the Comply Code: Revision 2

PDF Windrose Files (ZIP)(304 K)

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Background & Application


In 1985, the EPA asked the National Council on Radiation Protection and Measurements (NCRP) to develop simple screening methods for assessing compliance with the Clean Air Act by users of small quantities of radionuclideHelpradionuclideRadioactive forms of elements are called radionuclides. Radium-226, Cesium-137, and Strontium-90 are examples of radionuclides.s. NCRP published these procedures in 1986 and 1989 in Addendum to NCRP Commentary No. 3 on Determining Compliance with Environmental Standards (NCRP 89). EPA's COMPLY model was developed based on the procedures in Addendum to NCRP Commentary No. 3 on Determining Compliance with Environmental StandardsLearn about the National Council on Radiation Protection and Measurements (NCRP). Exit


COMPLY calculates the effective doseHelpeffective doseThe amount of radiation absorbed by an object or person, adjusted to account for the type of radiation received and the effect on particular organs. The unit used for effective dose is sievert (Sv, the international unit) or rem (U.S. unit). equivalent (ede) from radionuclides released from stacks and vents. Atmospheric concentrations are estimated using a Gaussian plume model and equations that account for building wake effects.

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Strengths & Limitations

The COMPLY computer software includes four increasing levels of complexity. A user can demonstrate compliance at any level. Level 1 requests the least amount of information: emission concentration or quantity possessed. However, under Level 1, "worst case" assumptions are used in the dose estimate. Level 4 requests the most information and uses site specific data instead of assuming the worst. The values estimated by this screening model are strictly for comparison with environmental standards and are not intended to represent actual doses to real people.

COMPLY has the advantage of accounting for building wake effects. It also can calculate dose at 10 meters from source to receptor, which enables assessment of receptors in or outside a building.

Use of COMPLY is not appropriate for estimating doses from sources that do not originate from an exhaust stack or vent.

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