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Compliance Levels for GRaDER Instrument Performance

The Countering Weapons of Mass Destruction (CWMD) Office was established in December 2017 by consolidating primarily the Domestic Nuclear Detection Office, a majority of the Office of Health Affairs, as well as other DHS elements.

For current information related to CWMD, please visit the following:

The Domestic Nuclear Detection Office (DNDO) will attest to instrument conformity with published standards based on independent third-party testing. This attestation uses published standards, compliance levels and criteria provided below, and it will be published in the form of a Graduated Rad/Nuc Detector Evaluation and Reporting (GRaDERSM) Evaluated Equipment List (GEEL).

In order to be considered for DNDO evaluation under the GRaDER Program, instruments must be tested by an independent, DNDO-accepted or National Voluntary Laboratory Accreditation Program (NVLAP)-accredited laboratory (for testing under National Institute of Standards and Technology (NIST) Handbook 150-23). The independent laboratory must provide the results of testing to the DNDO GRaDER Program in accordance with formats provided in the Test and Evaluation protocols published by NIST on behalf of DNDO.

The GEEL will be available on the password-protected GRaDER Program Homeland Security Information Network (HSIN) Community of Interest (COI) and the Federal Emergency Management Agency (FEMA) Responder Knowledge Base (RKB). A summary of the test evaluation results will also be available to authorized agencies, and the test report and DNDO evaluation report may be requested from DNDO through the GRaDER Program. Release of test reports will be determined using published guidance, coordination with the manufacturer, and stipulations of law.

Compliance Level Definitions

Level 0

For this level, the following conditions apply:

  • Test results are not yet available, or the DNDO evaluation is not completed.
  • An instrument does not meet the minimum subset of the ANSI/IEEE (American National Standard Institute/Institute of Electrical and Electronic Engineers) standards for levels 1, 2 or 3 and instrument categories listed below.
  • An instrument is found to have changed configurations since last tested.
  • An instrument has been on the GRaDER Evaluated Equipment List for four years or more without retesting. Its GRaDER Program attestation has expired.
  • An instrument is no longer in production, and production stopped one year or more ago.

Level 1

Instrument partially meets ANSI/IEEE standards and has demonstrated specified performance compared to selected key sections of the standards. Criteria for Level 1 are specifically defined for each instrument category listed below.

Level 2

Instrument fully meets ANSI/IEEE standards, unless otherwise exempted by the instrument category criteria listed below.

Level 3

Instrument meets Level 1 and/or Level 2 criteria listed below, and also satisfies the requirements of the applicable published government-unique technical capability standards.

The Department has adopted several ANSI/IEEE standards against which to test and evaluate radiation detection instruments. Listed below are the instrument categories and corresponding ANSI/IEEE N42 test standards that a given type of instrument must satisfy at each described compliance level. Additional levels may be designated once the technical capability standards are approved and published.

In the levels described here, the following word usage applies:

  • the word "shall" signifies a mandatory requirement (where appropriate, a qualifying statement is included to indicate that there may be an allowable exception);
  • the word "should" signifies a recommended specification or method;
  • the word "may" signifies an acceptable method or an example of good practice.

Instrument Categories, Standards and Compliance Level Criteria

Category 1 - Alarming Personal Radiation Detectors (PRDs)

ANSI N42.32-2006 American National Standard Performance Criteria for Alarming Personal Radiation Detectors for Homeland Security.

Manufacturers must define instrument capabilities and provide information required in Clauses 5 and 10 of the standard.

Level 1 - For this level some ANSI N42.32 requirements are either modified or removed. These modifications include changing requirements from "shall" to "should." If a requirement is not listed below, the instrument shall meet it as specified in the standard.

Instruments should meet the following:

  • Functionality Test (Section 5.7 ANSI N42.32-2006)
  • Vibration alarm (Section 5.9 ANSI N42.32-2006)
  • ANSI N42.42 Data format (Section 5.16 ANSI N42.32-2006)
  • Cold temperature start-up requirement (Section 7.5 ANSI N42.32-2006)
  • Vibration Test (Section 9.1 ANSI N42.32-2006)
  • Interfering ionizing radiation (Section 6.9 ANSI N42.32-2006)
  • Neutron detection is optional, so all sections involving neutron detection become "should."

Instruments shall meet the following modified requirements:

  • Time to alarm needs to be ≤ 4 seconds for Co and Cs, and it should respond to Am241 (Section 6.3 ANSI N42.32-2006).
  • Temperature range needs to be from 0°C to 40°C (Section 7.1 ANSI N42.32-2006).

Level 2 - The instrument shall meet all ANSI N42.32 requirements.

Level 3 - The instrument shall meet all Technical Capability Standards requirements when published.

Category 2 - Survey Meters

ANSI N42.33-2006 American National Standard for Portable Radiation Detection Instrumentation for Homeland Security.

Manufacturers must define instrument capabilities and provide information required in Clauses 5 and 10 of the standard.

Level 1 - For this level, some ANSI N42.33 requirements are either modified or removed. If a requirement is not listed below, the instrument shall meet it as specified in the standard.

Instruments should meet the following:

  • Functionality Test (Section 5.5 ANSI N42.33-2006)
  • Vibration (Section 5.7 ANSI N42.33-2006)
  • Batteries replaced without tools (Section 5.11 ANSI N42.33-2006)
  • ANSI N42.42 Data format (Section 5.12 ANSI N42.33-2006)
  • Cold temperature start-up (Section 7.5 ANSI N42.33-2006)
  • Vibration test (Section 9.1 ANSI N42.33-2006)
  • Photon energy response for 241 Am (Section 6.3 ANSI N42.33-2006).
  • Variation of response with angle of incidence for 241 Am (Section 6.3 ANSI N42.33-2006)

Instruments shall meet the following modified requirements:

  • Instruments are required to meet the accuracy test for exposure rates above 100 µR/h (Section 6.2 ANSI N42.33-2006).
  • Temperature range needs to be from 0°C to 50°C (Section 7.1 ANSI N42.33-2006).

Level 2 - The instrument shall meet all ANSI/IEEE N42.33 requirements.

Level 3 - The instrument shall meet all Technical Capability Standards requirements when published.

Category 3 - Radionuclide Identifiers (RIDs)

ANSI N42.34 2006 American National Standard Performance Criteria for Hand-Held Instruments for the Detection and Identification of Radionuclides.

Manufacturers must define instrument capabilities and provide information required in Clauses 5 and 10 of the standard.

Level 1 - For this level, some ANSI N42.34 requirements are either modified or removed. If a requirement is not listed below, the instrument shall meet it as specified in the standard.

Instruments should meet the following:

  • Interface Communication (Section 5.5 ANSI N42.34-2006)
  • User interface (Section 5.6 ANSI N42.34-2006)
  • Cold temperature start-up (Section 7.5 ANSI N42.34-2006)
  • Case construction (Section 5.2.6 ANSI N42.34-2006)
  • Spectral Identification (Section 5.10 ANSI N42.34-2006)
  • Personal protection alarm (Section 5.11 ANSI N42.34-2006)
  • Alarms (Section 6.4 ANSI N42.34-2006)
  • Interference from surrounding material (Section 6.11 ANSI N42.34-2006)
  • Neutron response (Section 6.13 ANSI N42.34-2006)
  • Over-range characteristics for exposure rate indication (Section 6.17 ANSI N42.34-2006)
  • Neutron indication in the presence of photons (Section 6.18 ANSI N42.34-2006)

Instruments shall meet the following modified requirements:

  • Reference point on case. Reference point identified in operating instructions or drawing is acceptable. (Section 5.2.6 ANSI N42.34-2006).
  • Location of effective center(s) or area(s) of detection (reference point) permanently fixed on instrument exterior. Reference point identified in operating instructions or drawing is acceptable. (Section 5.4.1.c ANSI N42.34-2006).
  • Warm-up time less than or equal to (≤) 6 minutes (Section 5.7.1 and 5.7.2 ANSI N42.34-2006).
  • Effective gamma ray energy response range should include 50keV to 3 MeV (Section 5.9.1 ANSI N42.34-2006).
  • Testing of the instrument shall be performed in the manufacturer-suggested operational mode (Section 6.5 ANSI N42.34-2006). Therefore, testing will occur in only one mode of operation.

Table 1. Expected Radionuclides and Daughters for Sources Listed in ANSI N42.34-2006. 

Radionuclide 
or Source

Required
Radionuclide 

Expected
Daughter 

40K

40K

None

57Co

57Co

None

60Co

60Co

None

67Ga

67Ga

None

99mTc

99mTc

99Mo

125I

125I

None

131I

131I

None

133Ba

133Ba

None

137Cs

137Cs

None

192Ir

192Ir

None

201Tl

201Tl

None

226Ra

226Ra

214Bi, 214Pb

232Th

232Th

212Bi, 212Pb, 228Ac

233U

233U

None

235U

235U

238U, 210Po

238U

238U

235U, 226Ra

Pu (RGPu)

239Pu

242Pu, 241Pu, 240Pu, 238Pu, 241Am, 237Np, 233Pa, 233U, neutron

241Am

241Am

None

  • Single radionuclide identification requirements is limited to the following list of unshielded radionuclides (identification within 2 minutes) - 40K, 60Co, 133Ba, 137Cs, 192Ir, 226Ra, 235U, 238U, Pu [Reactor grade plutonium (>10% 240Pu)], 241Am (Section 6.6.1 ANSI N42.34-2006).
  • Instruments are not required to identify the following list of radionuclides (Section 6.6 ANSI N42.34-2006):
    • Behind 5 mm steel shielding -40K, 125I, 226Ra, 233U, 235U, 238U, Pu (RG Pu containing >10% 240Pu), 241Am.
  • Simultaneous radionuclide identification – identify at least one of the two radionuclides within 2 minutes (Section 6.7 ANSI N42.34-2006).
  • Neutron detection is optional, therefore all tests involving neutrons become "should."
  • Temperature range from 0°C to 50°C (Section 7.1 and 7.2 ANSI N42.34-2006).

Level 2 - The instrument shall meet all ANSI N42.34 requirements except for the following modified requirements:

  • Testing of the instrument shall be performed in the manufacturer-suggested operational mode (Section 6.5 ANSI N42.34-2006). Therefore, testing will occur in only one mode of operation.
  • Instruments are not required to identify the following list of radionuclides (Section 6.6 ANSI N42.34-2006):
    • Unshielded - 233 U
    • Behind 5 mm steel shielding - 40 K, 125I, 226 Ra, 233 U, 235 U, 238 U, Pu [(Reactor grade plutonium (>10% 240 Pu)], 241 Am
  • NOTE - Testing laboratories need to base the 50 µR/h exposure rate on the radionuclide of interest. If the source used for testing has impurities (e.g., 241 Am impurity in a RGPu source), then the exposure rate for testing needs to be produced by the radionuclide of interest and not the impurities present in the source. This applies to Category 3 sources only.

Level 3 - The instrument shall meet all Technical Capability Standards requirements when published.

Category 4 - Radiation Detection Portal Monitors.

ANSI N42.35 2006 American National Standard for Evaluation and Performance of Radiation Detection Portal Monitors for Use in Homeland Security.

Manufacturers must define instrument capabilities and provide information required in Clauses 5 and 10 of the standard.

Level 1 - For this level, some ANSI N42.35 requirements are either modified or removed. If a requirement is not listed below, the instrument shall meet it as specified in the standard.

Instruments should meet the following:

  • Background effects test (Section 6.8 ANSI N42.35-2006)
  • AC line voltage test (Section 8.3 ANSI N42.35-2006)
  • Battery lifetime (Section 8.4 ANSI N42.35-2006)

Instruments shall meet the following modified requirements:

  • Temperature range needs to be from -10°C to 40°C (Section 7.1 ANSI N42.35-2006).
  • Gamma response (Section 6.4 ANSI N42.35-2006) and neutron response (Section 6.5 ANSI N42.35-2006) will not be tested at the maximum height of the detection zone for all categories. All other test heights are still determined assuming the full detection zone.

Level 2 - The instrument shall meet all ANSI N42.35 requirements.

Level 3 - The instrument shall meet all Technical Capability Standards requirements when published.

Category 5 - Spectroscopic Portal Monitors

ANSI N42.38 2006 American National Standard Performance Criteria for Spectroscopy - Based Portal Monitors Used for Homeland Security.

Manufacturers must define instrument capabilities and provide information required in Clauses 5 and 10.

Level 1 - For this level, some ANSI N42.38 requirements are either modified or removed. If a requirement is not listed below, the instrument shall meet it as specified in the standard.

Instruments should meet the following:

  • Power supply (Section 5.7 ANSI N42.38-2006)
  • Battery lifetime (Section 5.8 ANSI N42.38-2006)

Instruments shall meet the following modified requirements:

  • Temperature range needs to be from -10°C to 40°C (Section 7.1 ANSI N42.38-2006).
  • Gamma response (Section 6.3 ANSI N42.38-2006) and neutron response (Section 6.4 ANSI N42.38-2006) will not be tested at the maximum height of the detection zone for all categories. All other test heights are still determined assuming the full detection zone.
  • The source enrichment for all tests to be performed is changed to the following: HEU has an enrichment that is at least 90% 235 U, DU at 0.2% 235 U, and Unat at 0.7% 235 U, RGPu contains at least 10% 240 Pu, and WG Pu less than 6% 240 Pu (Section 6.14 ANSI N42.43-2006).
  • For the simultaneous radionuclide test (Section 6.8.4 ANSI N42.38-2006), zircon sand will be used instead of 40 K + 226 Ra + 232 Th. The total emission rate produced by the zircon sand needs to be a factor of 5 larger than that of the DU and the RG Pu.

Level 2 - The instrument shall meet all ANSI N42.38 requirements.

Level 3 - The instrument shall meet all Technical Capability Standards requirements when published.

Category 6 - Mobile and Transportable Systems

ANSI N42.43-2006 American National Standard Performance Criteria for Mobile and Transportable Radiation Monitors Used for Homeland Security.

Manufacturers must define instrument capabilities and provide information required in Clauses 5 and 10 of the standard. The manufacturer must indicate that the instrument is to be operated as transitory, stationary or both. Manufacturer must define the output files, data fields within those output files, and relate to compliance requirements in section 5.3 of the standard.

Level 1 - For this level, some ANSI N42.43 requirements are modified. If a requirement is not listed below, the instrument shall meet it as specified in the standard.

Instruments should meet the following:

  • Data storage (Section 5.3 ANSI N42.43-2006)
  • Transportable monitors used primarily for vehicle monitoring applications have ability to support occupancy sensors (Section 5.5.a ANSI N42.43-2006)
  • Occupancy sensors for vehicle monitors trigger circuit using external signal or through software for testing purposes (Section 5.5.e ANSI N42.43-2006)
  • Marking requirements (Section 5.6 ANSI N42.43-2006
  • Monitors have ability to operate from multiple power sources (Section 5.7.a ANSI N42.43-2006)
  • Communication protocol and data format (Section 5.10.1 ANSI N42.43-2006)
  • Warning/status indicators listed in section 5.10.2.1 except for alarm indication that remains a "shall" requirement (ANSI N42.43-2006)
  • Basic indications and functions (Section 5.10.2.2 ANSI N42.43-2006)
  • Advanced indications and functions (Section 5.10.2.3 ANSI N42.43-2006)
  • Overload test (Section 6.10 ANSI N42.43-2006)
  • Background effects (Sections 6.12 and 6.13 ANSI N42.43-2006)
  • Pile-up effects (Section 6.14.6 ANSI N42.43-2006)

Instruments shall meet the following modified requirements:

  • Testing for backpacks will be performed at a distance of 1.5 m (Section 5.1 ANSI N42.43-2006).
  • Testing with 252Cf for backpacks will be performed using a water phantom (Section 6.9 ANSI N42.43-2006). Approximate phantom dimensions 59 cm (H) x 35 cm (L) x 19 cm (D).
  • Gamma response (Section 6.8 ANSI N42.43-2006) and neutron response (Section 6.9 ANSI N42.43-2006) will not be tested at the maximum height of the detection zone for all categories. All other test heights are still determined assuming the full detection zone.
  • The source enrichment for all tests to be performed is changed to be the following: HEU has an enrichment that is at least 90% 235U, DU at 0.2% 235U, and Unat at 0.7% 235U, RGPu contains at least 10% 240Pu and WGPu less than 6% 240Pu (Section 6.14 ANSI N42.43-2006).

Table 2. Expected Radionuclides and Daughters for Sources Listed in ANSI N42.43-2006. 

Radionuclide 
or Source

Required
Radionuclide
Expected
Daughter

40K

40K

None

57Co

57Co

None

60Co

60Co

None

67Ga

67Ga

None

99mTc

99mTc

99Mo

131I

131I

None

133Ba

133Ba

None

137Cs

137Cs

None

192Ir

192Ir

None

201Tl

201Tl

None

226Ra

226Ra

214Bi, 214Pb

232Th

232Th

212Bi, 212Pb, 228Ac

237Np

237Np

233Pa, 233U

HEU

235U

238U, 210Po

DU

238U

235U, 226Ra

WGPu

239Pu

242Pu, 241Pu, 240Pu, 238Pu, 241Am, 237Np, 233Pa, 233U, neutron

RGPu

239Pu

242Pu, 241Pu, 240Pu, 238Pu, 241Am, 237Np, 233Pa, 233U, neutron

252Cf

Neutron detection

neutron, 252Cf, 249Cf

  • The radionuclide identification evaluation (Section 6.14.2 and 6.14.3 ANSI N42.43-2006) shall be limited to the categorization and radionuclides listed in section 6.5 Table 4 Activity Values for Gamma-ray and Neutron Sources and 6.14.1.
  • For the simultaneous radionuclide test (Section 6.14.4 ANSI N42.43-2006), zircon sand will be used instead of 40K + 226Ra + 232Th. The total emission rate produced by the zircon sand needs to be a factor of 5 larger than that of the DU and the RGPu.
  • Temperature range needs to be from -10°C to 40°C (Section 7.1 ANSI N42.43¬2006)

Level 2 - The instrument shall meet all ANSI N42.43 requirements.

Level 3 - The instrument shall meet all Technical Capability Standards requirements when published.

Category 7 - Spectroscopic Personal Radiation Detectors (SPRDs)

ANSI/IEEE N42.48-2008 American National Standard Performance Requirements for Spectroscopic Personal Radiation Detectors (SPRDs) for Homeland Security.

Manufacturers must define instrument capabilities and provide information required in Clauses 5 and 10 of the standard. Manufacturer must define the output files, data fields within those output files, and relate to the compliance requirements in section 5.12 of the standard.

Level 1 - For this level some ANSI N42.48 requirements are either modified or removed. These modifications include changing requirements from "shall" to "should." If a requirement is not listed below, the instrument shall meet it as specified in the standard.

Instruments should meet the following:

  • User Interface (Section 5.13 ANSI N42.48-2008)
  • Vibration alarm (Section 5.6 ANSI N42.48-2008)
  • ANSI N42.42 Data format (Section 5.12 ANSI N42.48-2008)
  • Cold temperature start-up requirement (Section 7.6 ANSI N42.48-2008)
  • Vibration Test (Section 9.1 ANSI N42.48-2008)
  • Interfering ionizing radiation (Section 6.9 ANSI N42.48-2008)

Instruments shall meet the following modified requirements:

  • Time to alarm needs to be ≤ 4 seconds for Co and Cs, and it should respond to Am241 (Section 6.3 ANSI N42.48-2008)
  • Temperature range needs to be from 0°C to 40°C (Section 7.2 ANSI N42.48-2008)

Table 3. Expected Radionuclides and Daughters for Sources Listed in ANSI N42.48-2008. 

Radionuclide 
or Source

Required
Radionuclide
Expected
Daughter

23Na

23Na

None

40K

40K

None

57Co

57Co

None

60Co

60Co

None

67Ga

67Ga

None

99mTc

99mTc

99Mo

123I

123I

None

131I

131I

None

133Ba

133Ba

None

137Cs

137Cs

None

152Eu

152Eu

None

192Ir

192Ir

None

201Tl

201Tl

None

226Ra

226Ra

214Bi, 214Pb

232Th

232Th

212Bi, 212Pb, 228Ac

241Am

241Am

None

HEU

235U

238U, 210Po

RGPu

239Pu

242Pu, 241Pu, 240Pu, 238Pu, 241Am, 237Np, 233Pa, 233U, neutron

252Cf

Neutron detection

neutron, 252Cf, 249Cf

Note: Section 6 Radiological test requirements.

Level 2 -The instrument shall meet all ANSI N42.48 requirements.

Level 3 -The instrument shall meet all Technical Capability Standards requirements when published.

DNDO periodically reviews these criteria for adequacy and applicability. DNDO is pursuing the coordination and development of the Technical Capability Standards that will soon be used by Federal agencies to augment the requirements outlined in the ANSI/IEEE N42 voluntary consensus standards. DNDO understands that the pertinent ANSI/IEEE voluntary consensus standards are under review and are likely to be republished in the next 2-3 years. Therefore, these criteria are likely to be revised to reflect the requirements of any newly published standards.

Last Updated: 08/02/2024
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