1、Designation: C 1055 03 (Reapproved 2009)Standard Guide forHeated System Surface Conditions that Produce ContactBurn Injuries1This standard is issued under the fixed designation C 1055; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision
2、, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This guide covers a process for the determination ofacceptable surface operating conditions for heated s
3、ystems.The human burn hazard is defined, and methods are presentedfor use in the design or evaluation of heated systems to preventserious injury from contact with the exposed surfaces.1.2 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thiss
4、tandard.1.3 The maximum acceptable temperature for a particularsurface is derived from an estimate of the possible or probablecontact time, the surface system configuration, and the level ofinjury deemed acceptable for a particular situation.1.4 For design purposes, the probable contact time forindu
5、strial situations has been established at 5 s. For consumerproducts, a longer (60-s) contact time has been proposed byWu (1)2and others to reflect the slower reaction times forchildren, the elderly, or the infirm.1.5 The maximum level of injury recommended here is thatcausing first degree burns on t
6、he average subject. This type ofinjury is reversible and causes no permanent tissue damage.For cases where more severe conditions are mandated (byspace, economic, exposure probability, or other outside con-siderations), this guide may be used to establish a second, lessdesirable injury level (second
7、 degree burns), where somepermanent tissue damage can be permitted. At no time,however, are conditions that produce third degree burns rec-ommended.1.6 This guide addresses the skin contact temperature de-termination for passive heated surfaces only. The guidelinescontained herein are not applicable
8、 to chemical, electrical, orother similar hazards that provide a heat generation source atthe location of contact.1.7 A bibliography of human burn evaluation studies andsurface hazard measurement is provided in the list of refer-ences at the end of this guide (1-16).1.8 This standard does not purpor
9、t to address all the safetyconcerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety andhealth practices and determine the applicability of regulatorylimitations prior to its use.2. Referenced Documents2.1 ASTM Standards:3C 680 Pr
10、actice for Estimate of the Heat Gain or Loss andthe Surface Temperatures of Insulated Flat, Cylindrical,and Spherical Systems by Use of Computer ProgramsC 1057 Practice for Determination of Skin Contact Tem-perature from Heated Surfaces Using a MathematicalModel and Thermesthesiometer3. Terminology3
11、.1 Definitions of Terms Specific to This Standard:3.1.1 skin:3.1.2 epidermisthe outermost layer of skin cells. Thislayer contains no vascular or nerve cells and acts to protect theskin layers. The thickness of this layer averages 0.08 mm.3.1.3 dermisthe second layer of skin tissue. This layercontain
12、s the blood vessels and nerve endings. The thickness ofthis layer averages 2 mm.3.1.4 necrosislocalized death of living cells. A clinicalterm that defines when permanent damage to a skin layer hasoccurred.3.1.5 burns:3.1.6 first degree burnthe reaction to an exposure wherethe intensity or duration i
13、s insufficient to cause completenecrosis of the epidermis. The normal response to this level ofexposure is dilation of the superficial blood vessels (reddeningof the skin).3.1.7 second degree burnthe reaction to an exposurewhere the intensity and duration is sufficient to cause completenecrosis of t
14、he epidermis but no significant damage to thedermis. The normal response to this exposure is blistering ofthe epidermis.1This guide is under the jurisdiction of ASTM Committee C16 on ThermalInsulation and is the direct responsibility of Subcommittee C16.30 on ThermalMeasurement.Current edition appro
15、ved Sept. 1, 2009. Published September 2009. Originallyapproved in 1986. Last previous edition approved in 2003 as C 105503.2The boldface numbers in parentheses refer to the list of references at the end ofthis guide.3For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact AST
16、M Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3.1.8 third degree burnthe re
17、action to an exposure wheresignificant dermal necrosis occurs. Significant dermal necrosishas been defined in the literature (3) as 75% destruction of thedermis. The normal response to this exposure is open sores thatleave permanent scar tissue upon healing.3.1.9 contact exposurethe process by which
18、 the surface ofskin makes intimate contact with a heated surface such that noinsulating layer, film, moisture, etc., interferes with the rapidtransfer of available energy.3.1.10 insulation systemthe combination of an insulationmaterial or jacket, or both that forms a barrier to the rapid lossof ener
19、gy from a heated surface. The insulation system mayinvolve a broad range of types and configurations of materials.3.1.11 jacketthe protective barrier placed on the exposedside of an insulation to protect the insulation from deteriorationor abuse. The jacket material can be made of paper, plastic,met
20、al, canvas cloth, or combinations of the above or similarmaterials.3.1.12 thermesthesiometera probe device developed byMarzetta (13) that simulates the thermal physical response ofthe human finger to contact with heated surfaces.4. Summary of Guide4.1 This guide establishes a means by which the engi
21、neer,designer, or operator can determine the acceptable surfacetemperature of an existing system where skin contact may bemade with a heated surface.4.2 The process used in the analysis follows the outlinelisted below:4.2.1 The user must first establish the acceptable contactexposure time and the le
22、vel of acceptable injury for theparticular system in question.4.2.2 Secondly, the user determines the maximum operatingsurface temperature. This determination is made either bydirect measurement (if possible) or by use of a calculation atdesign conditions using a method conforming to PracticeC 680.4
23、.2.3 Next, utilizing the contact time (4.2.1), the maximumsurface temperature (4.2.2), and the graph, Fig. 1, the userdetermines the potential injury level. If the operating point fallsbelow the injury level specified (4.2.1), then no further analysisis required. (See Note 1.)NOTE 1The following equ
24、ations have been developed from theoriginal data used to generate Fig. 1 for easier use of this figure.TA5 15.005 1 0.51907 3 Ln time 3 1000! 1 352.97/Ln time3 1000! (1)TB5 39.468 0.41352 3 Ln time 3 1000! 1 190.60/Ln time3 1000! (2)where:TA= critical contact temperature for complete transepidermal
25、ne-crosis, C.TB= critical contact temperature for reversible epidermal injury,C.time = elapsed contact time, s.Ln = natural logarithm.4.2.4 If the injury level exceeds that specified, furtheranalysis of the system is required using either the thermesthe-siometer (a direct method) or an additional ca
26、lculation. Bothmethods are described in Practice C 1057.4.2.5 If after this additional analysis the system still exceedsthe injury level criterion, then the system is unacceptable forthe criterion specified and the design should be revised.5. Significance and Use5.1 Most heated apparatus in industri
27、al, commercial, andresidential service are insulated, unless thermal insulationwould interfere with their function; for example, it is inappro-priate to insulate the bottom surface of a flatiron. However,surface temperatures of insulated equipment and appliancesmay still be high enough to cause burn
28、s from contact exposureunder certain conditions.5.2 This guide has been developed to standardize thedetermination of acceptable surface operating conditions forFIG. 1 Temperature-Time Relationship for BurnsC 1055 03 (2009)2heated systems. Current practice for this determination iswidely varied. The
29、intent of this guide is to tie together theexisting practices into a consensus standard based upon scien-tific understanding of the thermal physics involved. Flexibilityis retained within this guide for the designer, regulator, orconsumer to establish specific burn hazard criteria. Mostgenerally, th
30、e regulated criterion will be the length of time ofcontact exposure.5.3 It is beyond the scope of this guide to establish appro-priate contact times and acceptable levels of injury for particu-lar situations, or determine what surface temperature is “safe.”Clearly, quite different criteria may be ju
31、stified for cases asdiverse as those involving infants and domestic appliances, andexperienced adults and industrial equipment. In the first case,no more than first degree burns in 60 s might be desirable. Inthe second case, second degree burns in 5 s might beacceptable.NOTE 2An overview of the medi
32、cal research leading to the develop-ment of this guide was presented at the ASTM Conference on ThermalInsulation, Materials and Systems on Dec. 7, 1984 (14).5.4 This guide is meant to serve only as an estimation of theexposure to which an average individual might be subjected.Unusual conditions of e
33、xposure, physical health variations, ornonstandard ambients all serve to modify the results.5.5 This guide is limited to contact exposure to heatedsurfaces only. It should be noted that conditions of personalexposure to periods of high ambient temperature or highradiant fluxes may cause human injury
34、 with no direct contact.5.6 This guide is not intended to cover hazards for coldtemperature exposure, that is, refrigeration or cryogenic appli-cations.5.7 The procedure found in this guide has been described inthe literature as applicable to all heated surfaces. For extremelyhigh-temperature metall
35、ic surfaces (70C), damage occursalmost instantaneously upon contact.6. Procedure6.1 This procedure requires the user to make several deci-sions that are based upon the results obtained. Careful docu-mentation of the rationale for each decision and intermediateresult is an important part of this eval
36、uation process.6.2 The first phase in the use of this guide is to establish theacceptable limits for contact exposure time and the acceptablelevel of injury for the system in question. Where no availablestandards for these limits are prescribed, the following limitsare recommended based upon a surve
37、y of the existing medicalliterature.6.2.1 Acceptable Contact Times:6.2.1.1 Industrial Process5 s.6.2.1.2 Consumer Items60s.6.2.2 Acceptable Injury LevelsThe acceptable injury levelis that of first degree burns as defined in 3.1.6 and is the limitrepresented by the bottom curve in Fig. 1.6.3 The next
38、 phase in the process is to establish themaximum operating surface temperature under worst caseconditions. This evaluation may be made either by directmeasurement (but only at worst case conditions) or by using acalculation approximation. The steps required for determiningthe maximum surface tempera
39、ture are as follows:6.3.1 The initial step is to establish the operating systemparameters. This step provides input information to the analy-sis and may preclude any further work concerning burn hazard.The items that need to be identified and recorded are asfollows:6.3.1.1 System DescriptionShape, s
40、ize, materials, includ-ing jacket material, thickness, and surface emittance.6.3.1.2 Operation ConditionsTemperatures of heated sys-tem, times of year, cycle, etc.6.3.1.3 Ambient ConditionsWorst case design tempera-ture for burn hazards would be summer design dry bulb. Or, forinside conditions, the
41、maximum expected room ambient airtemperature. Include the ambient air velocity, if known.NOTE 3Design conditions for burn hazard evaluation may be differentfrom those used for heat loss analysis. For example, the highest ambientis used for burn hazard analysis versus the lowest for heat loss.6.3.2 T
42、he second step is to determine the temperature of thesystem surface at the worst design condition by one of thefollowing methods.6.3.2.1 Insert the system dimensions, material properties,and operating conditions into an analysis technique conformingto Practice C 680. This technique should be used du
43、ring designor where the system surface temperatures cannot be physicallymeasured at worst case conditions.6.3.2.2 Direct contact thermometry (thermocouple or resis-tance device) or infrared, noncontact thermometry.NOTE 4(1) Care should be used in attaching measurement devices onhot systems since bur
44、ns can result; and (2) Proper installation techniquesmust be used with direct contact thermometry to prevent heat sinking ofthe surface and obtaining incorrect temperature readings.6.4 In many situations, surface temperatures exceed therange of applicability of this guide and thus the evaluation ism
45、ade through interpretation of the surface temperature dataand the system properties. The limiting conditions belowshould first be examined to see if further analysis is required.6.4.1 If the surface temperature is below 44C, no shortterm (that is, less than 6 h) hazard exists and the remainingsectio
46、ns can be ignored.6.4.2 If the surface temperature exceeds 70C and thesurface is metallic, it may present a hazard regardless ofcontact duration.Attempts should be made to lower the surfacetemperature below 70C. Nonmetallic skins may be safe forlimited exposure at temperatures above 70C. In these ca
47、ses, aswith all cases between 44C and 70C, the analysis should becompleted.6.5 With the measurement or estimation of surface tempera-ture for the system in question, utilize the graph (Fig. 1) andcheck if the intersection of the operating surface temperatureand the selected time of contact falls bel
48、ow the thresholdtemperature.NOTE 5The threshold temperature used will depend on the limits ofacceptable burn chosen in 6.2.2. If the burn level is first degree, usethreshold line B in Fig. 1. If second degree burns are acceptable, usethreshold line A in Fig. 1.C 1055 03 (2009)36.6 If the operating s
49、urface temperature and time are belowthe threshold (line B) curve, then the system meets the selectedcriteria.6.7 If, however, the point falls above the curve, the systemmay meet the selected criterion only if certain combinations ofinsulation or jacketing, or both, are used. Analysis proceduresfor the jacketing/insulation effects are outlined in PracticeC 1057. Two methods provided in Practice C 1057 are brieflydescribed below.6.7.1 The calculation technique provided in Practice C 1057uses system geometry, material properties, and temperatur
