Measurement Techniques for Low Heat Flux Exposures to Fire Fighters Protective Clothing.
Measurement Techniques for Low Heat Flux Exposures to
Fire Fighters Protective Clothing.
(1735 K)
Vettori, R. L.; Twilley, W. H.; Stroup, D. W.
NIST SP 971; NISTIR 6750; 89 p. August 2001.
NIST SP 971: "Collected Reports and Publications by the
National Institute of Standards and Technology on Heat
Flux Gage Calibration and Usage.", 2001.
Available from:
For More Information on NIST SP 971 visit: WEBSITE:
http://www.bfrl.nist.gov/866/heatflux/index.htm
Order number: PB2001-106575
Keywords:
protective clothing; fire fighters; heat flux; exposure;
burns (injuries); fire research; sensors; temperature
measurements; test methods
Abstract:
A series of experiments were conducted to identify
measurement technologies that are appropriate for
evaluating the thermal performance of firefighter
protective clothing under low heat flux (less than or
equal to 5.0 kW/m2) exposure conditions and for
relatively long periods of time, up to 10 minutes.
Selected sensors were tested in six different
configurations and exposed to three different levels of
heat flux from a gas fired radiant panel. The 6
different configurations were (1) the sensor exposed to
the radiant panel with no contact with anything other
than the wires transmitting the sensor output signal (2)
the sensor mounted on a substrate such that the surface
of the sensor is flush with the surface of the substrate
and exposed to the radiant panel (3) a piece of
firefighter protective clothing is placed between the
sensor and the radiant panel, the sensor is touching the
back of the material (4) a piece of firefighter
protective clothing is placed between the sensor and the
radiant panel, the sensor is placed 6 mm behind the
material (5) a piece of firefighter protective clothing
is placed between the sensor and the radiant panel, the
sensor is mounted on the substrate and touching the back
of the material (6) a piece of firefighter protective
clothing is placed between the sensor and the radiant
panel, the sensor is mounted on the substrate and placed
6 mm behind the material. The three levels of heat flux
were 1.25 kW/m2, 2.50 kW/m2, and 5.00 kW/m2. For a given
configuration, there was a considerable variation in the
reported measurement between sensors. All sensors were
affected by placing them on the substrate. Based on the
results from this experimental series the
Schmidt-Boelter total heat flux gauge was deemed the
most appropriate for measuring incident heat flux. For
measuring the surface temperature of a fabric, the use
of a thermal pad, made of a material with a high thermal
conductivity to which is attached a thermocouple with
lead wires made of a material with a low thermal
conductivity, may be the most appropriate.
Building and Fire Research Laboratory
National Institute of Standards and Technology
Gaithersburg, MD 20899