ALMA-J Site Testing
ALMA-J Site Testing Archive
Last update 2005-05-11

Gamma-ray Dosimeter

    Gamma-ray dose was measured with two Polimaster PM-1621 dosimeters were used to record the absorbed dose near the AOS and the OSF. The detector of PM-1621 is a Geiger-Müller tube with a sensitivity range from 10 keV to 20 MeV.


    Detector Geiger-Muller tube
    Dose equivalent rate measurement range (DER) Hp(10):
    - PM1621
    - PM1621A
    0,1 mSv/h - 0,1 Sv/h
    0,1 mSv/h - 1 Sv/h
    Dose equivalent rate indication range (DER) Hp(10):
    - PM1621
    - PM1621A
    0,01 mSv/h - 0,2 Sv/h
    0,01 mSv/h - 2,0 Sv/h
    Dose equivalent rate threshold range Within all DER measurement range
    Dose equivalent measurement range Hp (10)
    Dose equivalent indication range Hp (10)
    1 mSv - 9.99 Sv
    0.01 mSv - 9.99 Sv
    Dose equivalent threshold range
    Maximum permissible intrinsic relative error of DER measurement (H - dose equivalent rate in mSv/h)
    Within all DE measurement range
    }(15+0.0015/H +0.01H)%
    Maximum permissible intrinsic relative error of DE measurement }15%
    Energy range 10.0 KeV - 20.0 MeV
    Energy response relative to 0,662 MeV (Cs-137) within the full energy range }30%
    Time of response at discontinuous variation of DER (according to IEC 61526), no more than 5s - at increase
    10s - at decrease
    Coefficient of variation <15%
    Survive after momentary influence of maximum permissible gamma radiation:
    - PM1621
    - PM1621A
    1 Sv/h
    10 Sv/h
    Additional functions PC communication mode
    Drop test on concrete floor 0.7 m
    Power supply One battery PANASONIC POWER LINE LR6 AA
    Battery lifetime (at natural conditions) 12 months
    Battery discharge indication (partial and critical) LCD indication
    Operating conditions:
    - temperature
    - LCD indication
    - relative humidity
    - pressure

    from - 40 up to +60R
    from - 20 up to +60R
    up to 98% at 35R
    from 84 up to 106,7 {Pa
    Degree of protection provided by housing IP67
    Dimensions 87 x 2 x 5 mm
    Weight (with battery), no more than 150 g

Technical Description