Thermo EPD Mk2, Technical Handbook

Page: 13 / 115

EPD/HB/40521/000
ISSUE 5
EPD TECHNICAL HANDBOOK Page 3
displayed to the user on a LCD display on the top of the EPD (see Figure 2.1). To
minimise the loss of data from battery or other failure, data is saved to secure
memory within the EPD every 15 minutes.
Data is written to and read from the EPD via an integral infra-red communications
interface. The Thermo Electron supplied
EasyEPD2 program reads and writes data
to the EPD via the Infra-red communications link and displays the data in a PC
window. Thermo Electron also produces a range of Access Control Systems for use
with the EPD.
Dose is accumulated separately in the EPD in three stores: Dose , Total Dose and
ADS Dose . The use of several stores allows dose to be recorded over differing
periods, for example the Dose store may be used for each job or task performed (
and reset after each ), whilst the Total Dose records the total or aggregate dose from
all the jobs or tasks performed. ADS Dose is a password -protected dose store
intended for ‘legal dosimetry’ applications. Note that audible alarms are given if either
the accumulated dose or dose rates exceed programmable threshold levels. Dose
alarms are raised against the
Dose store only.
The EPD is a sealed unit and is splash-proof. The unit will withstand short periods of
immersion in water but is not designed for prolonged immersion under pressure.
General maintenance is confined to:
♦
Removing/replacing the EPD battery,
♦
Removing/replacing the EPD clip assembly,
♦
Clearing fault conditions (where possible),
♦
Checking the functionality and calibration of the EPD,
♦
Keeping the unit clean.
Note:
1. This manual deals with Sieverts (Sv) throughout. To convert to rem multiply all
values by 100.