IEC 62363:2008 pdf free download

IEC 62363:2008 pdf free download Radiation protection instrumentation — Portable photon contamination meters and monitors
For assemblies intended for outdoor use，the manufacturer shall state the precautions thathave been taken to prevent the ingress of moisture.
5.5Alarm threshold
This clause is applicable to monitors only.
A monitor shall include circuits necessary for activating an alarm at one or more thresholds.The number of tripping levels shall be subject to agreement between manufacturer andpurchaser.
The values of alarm threshold shall be given either as percentages of the ranges or in termsof units of the display.
Each alarm threshold shall be designed to allow convenient operational verification by meansof test signals, radioactive sources or signal input circuitry.
The range of adjustment shall be specified and the value of the alarm threshold shall becapable of being adjusted to any point within this range. It shall not be possible toincapacitate the alarm by any means such as setting the alarm thresholds beyond rangelimits. lf a mute facility is provided it shall automatically reset when the alarm conditionceases.
Alarm threshold adjustments shall not be easily accessible to the operator (for examplekeyswitch operated or protected password).
5.6Pulse height thresholds
Measurement assemblies should have the facility to set pulse height thresholds，whichcorrespond to photon energy thresholds,in order to discriminate against interfering photonand/or beta radiations. Thresholds should be secure and only changed through internalcontrols or menus accessed by means of a password.
5.7 Measurement assembly indications
5.7.1 Meter display
The assembly should display the count rate.
Displays where the quantity displayed is derived from count rate such as activity should onlybe used where the radionuclide mix has been characterised. ln this situation,themeasurement assembly shall be programmed with the relationship between the surfaceemission rate and total activity (or activity per unit area) of the mix，taking account of thedecay efficiency of the radionuclide(s), the surface emission rate response and the sourceefficiency.The manufacturer shall state the method used to program the assembly with thisrelationship. Where the assembly indicates activity，the manufacturer should indicate theassumed surface area of the activity.The unit of activity shall be the Becquerel(Bq).
For digital displays，an additional pseudo-analogue graphical indication should be providedwhich shows the count rate (or activity) in terms of the proportion of the maximum of therange indication, for example a bargraph.
Where an instrument has a digital display， a feature shall be provided to check that allsegments of the display are operational.
Where linearly scaled displays are used for this application, autoranging functionality should also be provided.