Impact of Different Personal Protective Clothing on Wildland Firefighters' Physiological Strain

Abstract

Wildfire firefighting is an extremely demanding occupation performed under hot environment. The use of personal protective clothing (PPC) is needed to protect subjects from the thermal exposure. However, the additional use of PPC may increase the wildland firefighters' physiological strain, and consequently limit their performance. The aim of this study was to analyze the effect of four different PPC on the physiological strain of wildland firefighters under moderate conditions (30°C and 30% RH). Eight active and healthy wildland firefighters performed a submaximal walking test wearing a traditional short sports gear and 4 different PPC. The materials combination (viscose, Nomex, Kevlar, P-140 and fire resistant cotton) used during the PPC manufacturing process was different. During all tests, to simulate a real scenario subjects wore a backpack pump (20 kg). Heart rate, respiratory gas exchange, gastrointestinal temperature, blood lactate concentration, perceived exertion and temperature and humidity underneath the PPC were recorded throughout tests. Additionally, parameters of heat balance were estimated. Wearing a PPC did not cause a significant increase in the subjects' physiological response. The gastrointestinal temperature increment, the relative humidity of the microclimate underneath the PPC, the sweat residue in PPC, the sweat efficiency, the dry heat exchange and the total clothing insulation were significantly affected according to the PPC fabric composition. These results suggest that the PPC composition affect the moisture management. This might be taken into account to increase the wildland firefighters' protection in real situations, when they have to work close to the flames.

Fractional Contribution of Wildland Firefighters’ Personal Protective Equipment on Physiological Strain

“…In addition, wildland firefighters may perform their work in adverse conditions that involve smoke and particulate matter inhalation ( Adetona et al, 2016 ) and be exposed to both solar and flame radiation ( Keiser and Rossi, 2008 ; Rodríguez-Marroyo et al, 2012 ), which increase their heat stress ( González-Alonso et al, 1999 ; Cheuvront et al, 2010 ). Under these circumstances, the use of personal protective clothing (PPC) may exacerbate the wildland firefighters’ thermal strain ( Carballo-Leyenda et al, 2017 ) and limit their performance. In general, the PPC protective characteristics may interfere with thermoregulation, reducing or preventing the heat transfer and sweat evaporation ( Holmér, 2006 ; Cheung et al, 2010 ; Carballo-Leyenda et al, 2017 ).…”

“…Under these circumstances, the use of personal protective clothing (PPC) may exacerbate the wildland firefighters’ thermal strain ( Carballo-Leyenda et al, 2017 ) and limit their performance. In general, the PPC protective characteristics may interfere with thermoregulation, reducing or preventing the heat transfer and sweat evaporation ( Holmér, 2006 ; Cheung et al, 2010 ; Carballo-Leyenda et al, 2017 ). Therefore, the study of the wildland firefighters’ thermophysiological response to different PPC has acquired special relevance in recent years ( Den Hartog et al, 2016 ; Carballo-Leyenda et al, 2017 ).…”

Analysis of forest fire fatalities in Southern Europe: Spain, Portugal, Greece and Sardinia (Italy)

“…operations are adequate, safe and effective (Maditinos and Vassiliadis 2011;Cardil et al , 2016Jones et al 2016). Additionally, the abundance of WUI areas, and their exposure to such a phenomenal threat, poses a real challenge for civil protection and firefighting personnel (Caballero 2017). Although a wealth of assets have been duly allocated to fire suppression and prevention (Liang et al 2008), recent multiple-fatality events show that there is still a noticeable gap between the observed fire behaviour and the applied firefighting and self-protection capacity.…”

Fire intensity, individual protective clothing and firefighting safety

“…Therefore, firefighting safety demands the wearing of clothing with thermophysical properties appropriated to each firefighting feature, which include the assessment of the required activity level and of the thermal environment. These matters are described in the literature and are known by the firefighters which are aware of the individual protective clothing that should be used in each kind of fire (Sharkey 1999;McLellan & Selkirk 2005;Bröde et al 2010;Carballo-Leyenda et al 2017;McQuerry et al 2018).…”

“…Experimental studies concerning the thermophysiological response of firefighters carrying out typical firefighting activities (both structural and wildland), wearing the recommended protective clothing and exposed to environments that are representative of these fires have already been published (Carballo-Leyenda et al 2017;Fontana et al 2017;McQuerry et al 2018; among others). However, due to safety reasons of the individuals involved, these trials always terminate before firefighters reach levels of hyperthermic stress with the potential to cause heat-related illnesses.…”