ANALOX ADM Aspida, Руководство пользователя

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ADM & Sub Aspida
User Manual
Int. Approved
Document ref: PSA-811-22 March 2020 Page 24 of 45
Copyright © 2017 Analox Ltd. All Rights Reserved.
Commercial in Confidence
NOTE: USE IN A MOVING VEHICLE MAY PROVIDE ENOUGH
MOVEMENT TO DEFEAT THE MAN-DOWN DETECTION.
NOTE: MAN-DOWN IS DISABLED IF THE INSTRUMENT IS
CONNECTED TO USB OR CHARGER.
6.17 Panic alarm
In cases where a worker is in distress and still conscious, it is possible to activate the ultra-loud
siren manually. To activate the panic alarm, press and hold the button for a minimum of 1
second.
6.18 Time-weighted average (TWA) monitoring of carbon dioxide
Carbon dioxide is toxic to the human body as concentrations increase. Short term exposure to the
gas can be potentially lethal. Longer term exposure to more moderate levels of carbon dioxide can
also be detrimental to health, so health and safety bodies such as UK HSE define occupational
exposure levels (OEL) for the gas. These OELs provide a recommended safe exposure to carbon
dioxide whilst under working conditions. The occupational exposure levels are based on a
calculated time-weighted average (TWA) level of carbon dioxide in any one 24-hour period. The
TWA calculation is based on average carbon dioxide levels weighted to an assumed standard 8-
hour daily working shift.
The Analox Aspida has a facility which automatically calculates a TWA value on a per-user basis.
When a user powers on the device and selects a user ID, the Analox Aspida begins calculating and
contin
uously updating that user’s own TWA. The device also considers any historic data from the
last 24 hours which is relevant to the selected user. TWA data is logged alongside the actual gas
readings in the internal data log.
NOTE: IF NO USERS IDS ARE REGISTERED TO THE DEVICE, THE TWA
VALUES WILL ALL BE ATTRIBUTED TO A DEFAULT USER.
An alarm feature is provided which will warn of a high TWA exposure to carbon dioxide. In addition
to the normal 3 available gas alarms per sensor, carbon dioxide sensors have a 4
th alarm (priority
4) which is triggered when the calculated TWA value exceeds the TWA set-point. This alarm is set
by default to the UK HSE recommended OEL for carbon dioxide of 5000ppm (0.5%). When this
alarm is triggered, the red indicators, vibration and horn warnings will activate as with other gas
alarms. In the case of a TWA alarm, a TWA symbol will be shown below the carbon dioxide reading
on the display, as shown below. The TWA alarm is the lowest priority alarm and as such will be
over-ridden by any gas alarms triggered by a short-term increase in carbon dioxide levels.