![]() The test manikin is based on the 50 th percentile male Caucasian geometry 16 ), made from a high temperature epoxy composite shell structure, capable of withstanding incident heat flux of 8.4 k∙W∙m −2 for 60 s. The goal of this study was to determine which combinations of time and intensity of heat radiation people with appropriate personal protective equipment could be exposed without experiencing pain. So adequate protection is needed to operate in environments with high heat radiation levels. According to Rossi 11 ) skin temperature can still increase even when the heat source has already been removed after initial sensation of pain at 43☌. Most references in literature show that skin burns can occur at skin temperatures from 44☌ 9, 10 ). Based on the present knowledge maximum skin temperatures of 43☌ can be accepted as a relatively safe limit to prevent from harmful skin burns. ![]() Havenith and Daanen 8 ) mentioned a maximum skin temperature for pain of 43–45☌. As a consequence for generating European guidelines no reference will be made to risk of skin burns and the results will be limited to the possible experience of pain by the wearers of the protective clothing and equipment. Therefore, it is not allowed to determine safe work times referring to the time people will develop skin burns (health damage) 6 ) despite the use of personal protective equipment 7 ). Due to European legislation health and safety of employees must always be guaranteed and injuries avoided. This study intended to generate guidelines for work times under heat radiation exposure conditions not leading to health and safety hazards for the employees. In a study by Den Hartog and Heus 1 ) it was reported that thermal strain injuries 5 ) related to radiant heat stress at short term activities were improbable, however they did not go into details on the risks of skin burns. Additionally, a need was identified to define safe exposure limits for short term emergency response actions (15–30 min) during incidents in the (petrochemical) industry. The ‘1’ and ‘3’ k∙W∙m −2 contours were originally meant for prevention of heat strain during longer duration firefighting and rescue activities. In perspective of the revision of guideline for above ground storage of flammable liquids in vertical cylindrical tanks 4 ) there was a need to validate these safe working conditions for emergency responders in the 1 k∙W∙m −2, 3 k∙W∙m −2 and higher heat radiation contours. These calculated distances are called the 1 k∙W∙m −2 and 3 k∙W∙m −2 radiation contours. Generally the distance where the calculated radiant heat loads are 1 k∙W∙m −2 and 3 k∙W∙m −2 4 ) respectively are expected to be safe distances from these large scale fires. In industrial safety these fires are modelled and radiant heat loads are calculated to estimate safe working distances from the fire. When such incidents occur they are marked by very high levels of radiant heat and flames, much different from structural fires. ![]() Especially in the oil and gas industry, where large volumes of flammable liquids are stored, incidents are battled by industrial emergency responders and firefighters. In the industrial health sector, however, there is also a significant need in fire protective clothing (following requirements such as NFPA 2112 2 ) and EN 11612 3 )) as well as fire fighter protective clothing. ![]() Most research on protection against fire and radiant heat has been conducted to serve the first responders. At levels of 10.0 k∙W∙m −2 (emergency conditions) emergency responders should move immediately to lower heat radiation levels. Maximum working times in aluminized clothing at 6.3 k∙W∙m −2 was about five min. At higher heat radiation levels firefighter’s clothing gave insufficient protection and aluminized clothing should be used. With firefighter’s clothing it was possible to work almost three min up to 4.6 k∙W∙m −2. Operator’s clothing did not fulfil requirements to serve as protective clothing for necessary activities at heat radiation levels above 1.5 k∙W∙m −2 as was stated earlier by Den Hartog and Heus 1 ). Time till pain threshold (43☌) is set as a cut-off criterion for regular activities. The clothing was evaluated at four different heat radiation levels (3.0, 4.6, 6.3 and 10.0 k∙W∙m −2) in standing and walking posture with a thermal manikin RadMan™. To determine safe working conditions in emergency situations at petro-chemical plants in the Netherlands a study was performed on three protective clothing combinations (operator’s, firefighter’s and aluminized).
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