The TWL is an integrated measure of the dry bulb, wet bulb, wind speed and radiant heat. From these variables, and taking into consideration the type of clothing worn and acclimatization state of the worker, the TWL predicts the maximum level of work that can be carried out in a given environment, without workers exceeding a safe core body temperature 38.2 °C (100.8 °F) and sweat rate (< 1.2 kg or 2.6 lb per hour). WBGT does not incorporate direct measure of wind speed and requires estimation of metabolic rates, which can have a margin of error up to 50%. Heat stress indexes such as WBGT and ISO 7933 do not take into account the effects of long hours of hard work, dehydration, or the impact of personal protective clothing and equipment. WBGT and heat index are too conservative and inappropriate for practical in extreme working environment such as Middle East countries or high temperature process industry or mines. Scarlet TWL-1S incorporated both WBGT and TWL index features. You can simply switch heat indices for your need. Visit Scarlet for more details www.scarlet.com.tw

1. Madeheatstressmanagementeasy
Heat Stress Monitor
TWL1 s

2. Scarlet Tech
Designing portable instruments
Founded in 2011,Taipei,Taiwan
scarlet.com.tw
Connecting to international academy
Fusing medical knowledge and technology taste
Coordinate local manufactures to implement the design

3. TWL1 s
Measure Environment
Calculate Heat Index
&

4. Measure
Environment
Web bulb temperature (Tw)
Air temperature (Ta)
Globe temperature (Tg)
Wind speed (WS)
Sample parameters
TEMP
FELT
TEMP
WBGT TWL
Calculate
Heat Index
Give scientific-based index

5. Mandatory
© Scarlet Tech Co. Ltd. 2013 www.scarlet.com.tw +886 2 2325 7712

6. 4 Sensors
GLOBE RH%
TEMP WIND

7. Globe
Temperature
Small 3”black ball, for portable
Range 0...80℃
Accuracy ±1.0℃ (15...40℃)
Built-in correction factor for standard 6”
Reach 90% equilibrium in 7 min

8. Relative
Humidity
Capacitive sensor, small and responsive
Range 5...95%rh
Accuracy ±3% @ (10...90 %rh) 25℃
Capacitive sensor 140pF±40pF
Responsive.Took 12 sec from 10% to 80%

9. AirTemperature
Small size, industrial spec
Range 0...60℃
Accuracy ±0.6℃
NTC type thermistor
Beneath globe. Prevent from radiation heat

10. Wind Speed
Wind cup. No worries about wind direction
Range 0.5...10 m/s
Accuracy ±(2% reading + 0.2) m/s
Wind tunnel lab calibrated
Optical method (IR) to read out RPM

11. indoor
4 Calculations
WET
BULB
WBGT
WBGT
outdoor
TWL

12. indoor
WBGT
WBGT
outdoor
WBGT
The US Army proposedWBGT in 1957
Comply with ISO 7243, ACGIHTLV, ISO 7730
WBGT indoor = 0.7 xTw + 0.3 xTg
Wet Bulb GlobeTemperature
WBGT outdoor = 0.7 xTw + 0.2 xTg + 0.1Ta

13. everything in one device
Best solution
four sensors
wet bulb measure RH: 5-95% accuracy 0.1%
calculator
globe 0-80℃, accuracy 0.1℃
Wind 0.5-10 m/s, accuracy 0.1 m/s
Dry bulb 0-50℃, accuracy 0.1℃
© Scarlet Tech Co. Ltd. 2013 www.scarlet.com.tw +886 2 2325 7712
table
Zone Risk Level Cycle (min)
TWL ≥ 140 Low Continuous*
115 ≤ TWL < 140 Medium Continuous*
TWL < 115 High 20 work - 40 rest

14. dashboard
Best solution
© Scarlet Tech Co. Ltd. 2013 www.scarlet.com.tw +886 2 2325 7712
3-color LCD backlight R/Y/G indicates risk level
Risk icons is readable alternative in sunlight
On screen timer is helpful for safety manager to
schedule work-rest cycle based on TWL value
innovative display

15. data logger
Best solution
© Scarlet Tech Co. Ltd. 2013 www.scarlet.com.tw +886 2 2325 7712
logger TWLIT
For research purpose
For build up database of forecast
Configurable sample rate: 10 min to 4 hr/data
Standard mini USB connector
PC software to download data and setup device
Download data in zero click. Simple
Configure device name
Configure sampling rate
Export CSV for Excel analysis
210
255
300
12.06 12:36 13:06 13:36
TWL RH (normalized)

16. sensor protection
Best solution
© Scarlet Tech Co. Ltd. 2013 www.scarlet.com.tw +886 2 2325 7712
protect rh sensor
Polypropylene (PP) film allows vapor going
through but blocks fine dust and dirt. So vapor
and moisture reach sensor but particles don’t.
This design is to extend the life of sensor in harsh
environment.
Protect anemometer bearing
A silicone pad clamped on top of the plate of wind
miller plate. This prevents the bearing inside of
the structure from dust and other particles.
Compare to competitors, this effectively extends
the sensor life.

17. calibration & parts
Services
© Scarlet Tech Co. Ltd. 2013 www.scarlet.com.tw +886 2 2325 7712
humidity wind cup
>> Calibration
Should calibrate every 6 months.
Local agent or clients can do it.
>> Parts
Pp filter is suggested to be
replaced every 2 to 4 weeks in
heavy usage. By order.
Dry/globe bulb
>> Calibration
Calibration drift of thermistors are
negligible. No need to calibrate.
>> Parts
Black ball along with thermistor is
replaceable. By order.
>> Calibration
Local calibration is not feasible due
to wind tunnel costs.
>> Quick check
Hold device and walk 5 meters in
10 sec and make sure the cups
keep rotating.
>> Parts
Wind cup and bearing is
replaceable. By order.

18. Free PC Software

19. Portability is Considered

20. EN 61326-1:2006
(IEC/EN61000-4-2 (2009)/
-3 (2006 + A2:2010))
Electrical Equipment for
Measurement,
Control and Laboratory Use
Certification

21. Middle East includes Abu Dhabi,
Dubai, Oman, Iran, KSA. Australia
and New Zealand
Region Industry
Construction, oil and gas, open-
cut mining, aluminum ,glass,
forest management, cement,
transportation, government
Our Customers

22. Brand
Our Customers

23. CustomerVisiting
We visited 100+ companies in 18 months

24. Construction
Reach 50 °C in summer.
Risk assessment is
mandatory and essential

25. Abu Dhabi
Municipality
Safety in the heat conference.
Scarlet was invited and had a
booth

26. Plastic Plant
Introduction and training

27. Dubai, UAE
World Expo 2020
Introduction and training

28. Road Construction
Introduction and training

29. Mall Beside F1Track

30. Cement Plant

31. Metal Manufacture

32. Cable Factory
Reach 60 °C @ 2 meter.
Heat risk assessment is
mandatory

33. Improvement
Validation
Increase ventilation in the site