Advertisement

Prehospital Use of Ultrathin Reflective Foils

Published:January 05, 2022DOI:https://doi.org/10.1016/j.wem.2021.11.006
      Ultrathin reflective foils (URFs) are widely used to protect patients from heat loss, but there is no clear evidence that they are effective. We review the physics of thermal insulation by URFs and discuss their clinical applications. A conventional view is that the high reflectivity of the metallic side of the URF is responsible for thermal protection. In most circumstances, the heat radiated from a well-clothed body is minimal and the reflecting properties of a URF are relatively insignificant. The reflection of radiant heat can be impaired by condensation and freezing of the moisture on the inner surface and by a tight fit of the URF against the outermost layer of insulation. The protection by thermal insulating materials depends mostly on the ability to trap air and increases with the number of covering layers. A URF as a single layer may be useful in low wind conditions and moderate ambient temperature, but in cold and windy conditions a URF probably best serves as a waterproof outer covering. When a URF is used to protect against hypothermia in a wilderness emergency, it does not matter whether the gold or silver side is facing outward.

      Keywords

      To read this article in full you will need to make a payment

      Purchase one-time access:

      Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online access
      One-time access price info
      • For academic or personal research use, select 'Academic and Personal'
      • For corporate R&D use, select 'Corporate R&D Professionals'

      Subscribe:

      Subscribe to Wilderness & Environmental Medicine
      Already a print subscriber? Claim online access
      Already an online subscriber? Sign in
      Institutional Access: Sign in to ScienceDirect

      References

        • Renström B.
        Space or rescue blanket – a bluff?.
        Arctic Med Res. 1992; 51: 212-213
        • Buggy D.
        • Gardiner J.
        The space blanket and shivering during extradural analgesia in labour.
        Acta Anaesthesiol Scand. 1995; 39: 551-553
        • Whitney A.M.
        The efficiency of a reflective heating blanket in preventing hypothermia in patients undergoing intra-abdominal procedures.
        AANA J. 1990; 58: 212-215
        • Besson U.
        Paradoxes of thermal radiation.
        Eur J Phys. 2009; 30: 995-1007
        • Henriksson O.
        • Lundgren J.P.
        • Kuklane K.
        • Holmér I.
        • Bjornstig U.
        Protection against cold in prehospital care-thermal insulation properties of blankets and rescue bags in different wind conditions.
        Prehosp Disaster Med. 2009; 24: 408-415
        • Ennemoser O.
        • Ambach W.
        • Flora G.
        Physical assessment of heat insulation rescue foils.
        Int J Sports Med. 1988; 9: 179-182
        • Zasa M.
        • Flowers N.
        • Zideman D.
        • Hodgetts T.J.
        • Harris T.
        A torso model comparison of temperature preservation devices for use in the prehospital environment.
        Emerg Med J. 2016; 33: 418-422
        • Kerslake D.M.
        The value of reflecting layers in clothing.
        Proc R Soc Med. 1969; 62: 283-284
        • Marcus P.
        • Robertson D.
        • Langford R.
        Metallised plastic sheeting for use in survival.
        Aviat Space Environ Med. 1977; 48: 50-52
        • Isser M.
        • Kranebitter H.
        • Fink H.
        • Wiedermann F.J.
        • Lederer W.
        High tensile strength increases multifunctional use of survival blankets in wilderness emergencies.
        Wilderness Environ Med. 2020; 31: 215-219
        • Isser M.
        • Kranebitter H.
        • Kofler A.
        • Groemer G.
        • Wiedermann F.J.
        • Lederer W.
        Rescue blankets hamper thermal imaging in search and rescue missions.
        SN Appl Sci. 2020; 2: 1486-1493
        • Kranebitter H.
        • Wallner B.
        • Klinger A.
        • Isser M.
        • Wiedermann F.J.
        • Lederer W.
        Rescue blankets-transmission and reflectivity of electromagnetic radiation.
        Coatings. 2020; 10: 375-383
        • Sanchez-Marin F.J.
        • Calixto-Carrera S.
        • Villaseñor-Mora C.
        Novel approach to assess the emissivity of the human skin.
        J Biomed Opt. 2009; 14024006
        • Zhang H.
        • Hu T.L.
        • Zhang J.C.
        Surface emissivity of fabric in the 8–14 μm waveband.
        J Textile Inst. 2009; 100: 90-94
        • Charkoudian N.
        Skin blood flow in adult human thermoregulation: how it works, when it does not, and why.
        Mayo Clin Proc. 2003; 78: 603-612
        • Webb P.
        Temperatures of skin, subcutaneous tissue, muscle and core in resting men in cold, comfortable and hot conditions.
        Eur J Appl Physiol Occup Physiol. 1992; 64: 471-476
        • Shitzer A.
        Assessment of the effects of environmental radiation on wind chill equivalent temperatures.
        Eur J Appl Physiol. 2008; 104: 215-220
        • Richards M.G.
        • Rossi R.
        • Meinander H.
        • Broede P.
        • Candas V.
        • den Hartog E.
        • et al.
        Dry and wet heat transfer through clothing dependent on the clothing properties under cold conditions.
        Int J Occup Saf Ergon. 2008; 14: 69-76
        • Henriksson O.
        • Lundgren P.
        • Kuklane K.
        • Holmér I.
        • Naredi P.
        • Bjornstig U.
        Protection against cold in prehospital care: evaporative heat loss reduction by wet clothing removal or the addition of a vapor barrier—a thermal manikin study.
        Prehosp Disaster Med. 2012; 27: 53-58
        • Havenith G.
        • Heus R.
        • Lotens W.A.
        Resultant clothing insulation: a function of body movement, posture, wind, clothing fit and ensemble thickness.
        Ergonomics. 1990; 33: 67-84
        • Mert E.
        • Psikuta A.
        • Bueno M.-A.
        • Rossi R.M.
        Effect of heterogenous and homogenous air gaps on dry heat loss through the garment.
        Int J Biometeorol. 2015; 59: 1701-1710
        • Lotens W.A.
        • Pieters A.M.J.
        Transfer of radiative heat through clothing ensembles.
        Ergonomics. 1995; 38: 1132-1155
        • Sun Y.
        • Chen X.
        • Cheng Z.
        • Feng X.
        Study of heat transfer through layers of textiles using finite element method.
        Int J Cloth Sci Technol. 2010; 22: 161-173
        • Chen Y.S.
        • Fan J.
        • Qian X.
        • Zhang W.
        Effect of garment fit on thermal insulation and evaporative resistance.
        Textile Res J. 2004; 74: 742-748
        • Havenith G.
        • Richards M.G.
        • Wang X.
        • Bröde P.
        • Candas V.
        • den Hartog E.
        • et al.
        Apparent latent heat of evaporation from clothing: attenuation and “heat pipe” effects.
        J Appl Physiol (1985). 2008; 104: 142-149
        • Bröde P.
        • Havenith G.
        • Wang X.
        • Candas V.
        • den Hartog E.A.
        • Griefahn B.
        • et al.
        Non-evaporative effects of a wet mid layer on heat transfer through protective clothing.
        Eur J Appl Physiol. 2008; 104: 341-349
        • Drummeter L.H.
        • Hass G.
        Solar absorptance and thermal emittance of evaporated coatings.
        in: Hass G. Thun R.E. Physics of Thin Films. Academic Press, New York1964: 305-361
        • Bennett J.M.
        • Ashley E.J.
        Infrared reflectance and emittance of silver and gold evaporated in ultrahigh vacuum.
        Appl Optics. 1965; 4: 221-224
        • Savage C.J.
        Thermal control of spacecraft.
        in: Fortescue P. Swinerd G. Stark J. Spacecraft System Engineering. 4th ed. Wiley, 2011: 357-390
        • Light I.M.
        • Norman J.N.
        The thermal properties of a survival bag incorporating metallised plastic sheeting.
        Aviat Space Environ Med. 1980; 51: 367-370
        • Watts D.D.
        • Roche M.
        • Tricarico R.
        • Poole F.
        • Brown J.J.
        • Brown Jr., J.J.
        • et al.
        The utility of traditional prehospital interventions in maintaining thermostasis.
        Prehosp Emerg Care. 1999; 3: 115-122
        • Jussila K.
        • Rissanen S.
        • Parkkola K.
        • Hannu A.
        Evaluating cold, wind, and moisture protection of different coverings for prehospital maritime transportation - a thermal manikin and human study.
        Prehosp Disaster Med. 2014; 29: 580-588