This product is now obsolete.
The Microtherm WBGT from Casella CEL
is an ergonomically designed, compact,
and rugged instrument designed to
monitor heatstress potential of personnel
in hot working environments in accordance
with ISO 7243. It is the first heat stress
meter that offers real-time graphical display
of data and also features an audible/visual
alarm which allows the operator to make
rapid decisions if required. PC software for
retrospective data analysis is included.
What is Heat Stress?
Workers exposed to hot working
environments can be susceptible to
heatstress, when the core body temperature
rises to dangerous or hazardous levels. This
can result in physiological symptoms like
heatcramps, nausea, palpitations, stroke and
An overall estimation of heat
stress levels on the body can be measured
by utilising the Wet Bulb Globe Temperature
Index (WBGT). This combines the measurement
of three parameters; natural wet bulb
temperature (tnw), globe temperature (tg)
and air temperature (ta), applied to the
following formulae for both indoor and
WBGT (Indoor) = 0.7tnw + 0.3tg
WBGT (Outdoor) = 0.7tnw+ 0.2tg + 0.1ta.
The data collected for these values are
compared to reference values (as defined
by the standard and appropriate “work rest”
regimes) can then be adopted in the
workplace or more detailed medical
Large LCD graphics display
Full data-logging facilities as
Low water level warning
Audible / visual alarm for
%RH and dewpoint calculation
Long battery life
10m extension cables available
PC software included
Meets requirements of ISO 7243
Automatic calculation of work rest regimes via PC software
Tripod mounting for meter and remote sensor array
Medical surveillance testing
The WBGT meter measures simultaneously from three PRTD
sensors for Wet Bulb, Dry Bulb and Globe Temperatures.
Sensors are manufactured to high accuracy standards:
BS EN60751 and DIN 43760.
Processed data values include:
WBGT (indoor and outdoor)
1 Hour (TWA) WBGT values
Relative Humidity (%)
Sensors can be used either
attached directly on the body
of the unit, or remotely
via 10m extension cables.
Both the electronic
unit and sensor array can be
(tripod not included).
The Microtherm WBGT incorporates a large 128 x 64 pixel
graphics LCD with backlight, capable of displaying data
in two modes;
The Microtherm WBGT is the first area heat stress instrument to
offer a real-time scrolling graph of the temperature parameters
being measured. This display can be shown over variable time
bases of 15, 30, 60 & 120 minutes. This allows the user to assess
how the environment is changing over time, without having to
download to a PC.
Instantaneous values for all parameters are displayed,
combined with the hourly rolling average values.
An adjustable alarm threshold may be defined for one selected
data channel: WBGTtwa, WBGT, Ta or OFF. An audible alarm and
flashing visual message on the display screen provides warning
of excedence of the threshold.
Simple Keypad Operation
The Microtherm WBGT has been designed with a simple, easy to
use menu structure for the displaying of information, instrument
configuration and retrieval of data. The access of this menu via the
touch keypad and screen prompts, ensures ease of use for the
The software (WinHSM) provides an interface for data collection to PC
for retrospective analysis. It produces graphical and tabular reports
which can easily be imported into other applications. Summary and
WBGT Heat Stress Index reports can also be generated.
Work rest regimes are calculated, Clothing (Clo) correction factors,
and metabolic rates can be entered in accordance with OSHA and
Data can also be viewed “live” by selection of the real-time option
whilst connected to the PC.
Calibration of the Microtherm WBGT is performed against an internal
reference prior to every single measurement. This ensures a high
accuracy for each of the temperature sensors and eliminates the need
for annual recalibration. Sensor arrays are also interchangeable without
need for recalibration.
180000A - Microtherm Heat Stress WBGT meter with kit case
180042A - Microtherm Heat Stress WBGT meter with kit case with calibration certificate
180043B - 10m Extension Lead for sensor array
CEL-90330 - Small Tripod (max height 215mm)
CEL-6713 - Standard Tripod (max height 1,160mm)
Microtherm Heat Stress WBGT kit includes:
Microtherm Heat Stress WBGT meter
Pack of spare wicks and screwdriver
Rechargeable batteries (x4)
Universal mains PSU (110/240VAC) with UK, Europe and USA plug adaptors
Distilled water countainer
RS232 communication cable (USB adaptor available)
Windows Win HSM software
Hard carrying case