1、Designation:F 1491 93(Reapproved 2002)Standard Specification forAn Avalanche Beacon Frequency1This standard is issued under the fixed designation F 1491;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A numb
2、er in parentheses indicates the year of last reapproval.Asuperscript epsilon(e)indicates an editorial change since the last revision or reapproval.1.Scope1.1 This specification establishes a National AvalancheBeacon Frequency.2.Terminology2.1 Definitions of Terms Specific to This Standard:2.1.1 aval
3、anche beaconan electronic device for radiolocation of persons buried or trapped,usually by snow,andemploying radio frequency electromagnetic induction.3.Requirements3.1 Standard FrequencyThe avalanche beacon shall op-erate on a frequency of 457.0 kHz.3.2 Additional Interim FrequencyThe avalanche bea
4、conmay also operate on a frequency of 2.275 kHz.3.3 Frequency PrioritiesThe standard frequency(457.0kHz)is mandatory in all devices.Use of the interim frequency(2.275 kHz)shall not impair or disable effective operation withthe standard frequency.3.4 Transition to Standard FrequencyBoth frequenciessh
5、ould be employed during the interim period.Incorporation ofthe interim frequency is intended to provide temporary back-ward interoperability with older beacons,until such devicescan be replaced or retired.Beacons incorporating both frequen-cies should be employed until December 31,1995.After thisdat
6、e,only single frequency(457.0 kHz)beacons should beemployed and the use of 2.275(kHz)should be discontinued.4.Significance and Use4.1 Avalanche beacons are used for the location of personswho are buried by avalanches.In operation,users wear thebeacons,which are all set to transmit.After an incident,
7、therescuers switch their units to receive and search for the subject,whose units are still in transmit.5.Keywords5.1 avalanche;beacon;frequency;snow;transceiverASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this stan
8、dard.Users of this standard are expressly advised that determination of the validity of any such patent rights,and the riskof infringement of such rights,are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed
9、 every five years andif not revised,either reapproved or withdrawn.Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters.Your comments will receive careful consideration at a meeting of theresponsible tech
10、nical committee,which you may attend.If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards,at the address shown below.This standard is copyrighted by ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA
11、 19428-2959,United States.Individual reprints(single or multiple copies)of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585(phone),610-832-9555(fax),or serviceastm.org(e-mail);or through the ASTM website(www.astm.org).1This specification is under the jurisdicti
12、on of ASTM Committee F32 on Searchand Rescue and is the direct responsibility of Subcommittee F32.01 on Equipment,Testing,and Maintenance.Current edition approved August 15,1993.Published October 1993.1Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959,United States.