ForewordThe purpose of this standard is to specify performance and design criteria for personal electronic monitors used for the determination of personal dose equivalent@ or dose equivalent rate from external sources@ of radiation. It is necessary to standardize the performance and design of devices used for this important purpose. Recent developments in this area of instrumentation have necessitated the revision of ANSI N42.20-1995 for these devices. This standard should be used in conjunction with ANSI N42.17a-2003.ScopeThis standard applies to the following types of active electronic devices that are worn on the trunk of the body for the purpose of measuring the personal dose equivalent@ or dose equivalent rate from external sources@ of radiation. The types of dosimeters@ include those designed for measuring@ are the following: Type 1??X@ gamma@ and high energy beta radiations Type 2??Neutron radiation Type 3??X@ gamma@ high energy beta@ and neutron radiations (i.e.@ total dose) The standard specifies the design and performance criteria for the personal electronic dose monitors and@ if supplied@ the associated readout system. It applies to devices used for the measurement of personal dose equivalent (rate) from photon radiations (X-rays and gamma rays) of energies 50 keV to 1.5 MeV@ beta radiation of maximum energies greater than 500 keV@ and neutron radiation from thermal energies to approximately 15 MeV. This standard does not include instruments referred to as chirpers@which are described in ANSI N13.27-1981. This standard does not specify methods for the proficiency testing and accreditation of dosimetry systems. The standard addresses only the radiation detection portions of instruments with telemetric capability. It also does not address passive devices such as thermoluminescent dosimeters@ photographic film dosimeters@ or quartz fiber electroscope dosimeters. This standard specifies the following items for active personal electronic dosimeters: required general characteristics; general testing procedures; radiation characteristics; and electrical@ mechanical@ safety@ and environmental characteristics. The standard specifies the criteria for validating the accuracy of stored dosimetry information. This standard should be used for the evaluation of active personal electronic dosimeters as part of a type testing program or a qualification of the devices for purchase and subsequent use in a radiation protection program. The proficiency testing or accreditation of these devices is covered in related standards developed by Accredited Standards Committee (ASC) N13.?