Thermal Ergonomics Standards

Thermal ergonomics standards are relevant where heat or cold are factors in the environment and are important in sports, fire fighting, construction, surgery and other occupations. Thermal ergonomic standards are important to protective clothing manufacturers and workers in extreme environments. Thermal ergonomic standards promote safety, productivity, health and well-being. ISO TC 159 is a technical committee involved in standardization in the field of ergonomics. ISO TC 159 SC5 is a subcommittee working on ergonomics of the physical environment. Within this category are thermal ergonomics standards for measurement of physical quantities, analysis and interpretation of thermal stress on workers, methods for the assessment of human responses to hot and cold as well as other standards.

The University of Ottowa Thermal Egronomics Laboratory conducts research in the field of thermal ergonomics and looks at health, performance and the human body's response to heat and cold. The Health Safety Executive has resources, legislation and publications for further reading on the topic of thermal comfort and occupational exposure to heat and cold.

ISO 13731:2001

Ergonomics of the thermal environment - Vocabulary and symbols

This International Standard defines physical quantities in the field of the ergonomics of the thermal environment. The corresponding symbols and units are also listed. The aim of this International Standard is to give vocabulary and symbols for the quantities used in International Standards on ergonomics of the thermal environment, to provide a reference of vocabulary and symbols to be used in writing future International Standards or other publications on the ergonomics of the thermal environment.

ISO 10551:2019

Ergonomics of the physical environment - Subjective judgement scales for assessing physical environments

This document presents principles and examples of practical application for the construction of appropriate subjective scales for use in the assessment and evaluation of the physical environment. It does not standardize particular scales. It considers scales of perception, comfort, preference, acceptability, expression form and tolerance, and environmental components such as thermal, visual, air quality, acoustic and vibration. It does not consider other scales such as: scales related to the effects of the environment on the ability to read displays or signs, on manual performance or on psychological conditions such as mood, etc.; scales related to pain or scales related to stimuli that can lead to injury. This document does not present principles of surveys (see Note) or questionnaire design. However, the scales that are developed using this document can be incorporated into surveys or questionnaires. NOTE Environmental surveys are described in ISO 28802. ISO 28802 includes scales that are complementary to, and based upon, the principles of scale construction that are described in this document.

ISO 11079:2007

Ergonomics of the thermal environment - Determination and interpretation of cold stress when using required clothing insulation (IREQ) and local cooling effects

ISO 11079:2007specifies methods and strategies for assessing the thermal stress associated with exposure to cold environments. These methods apply to continuous, intermittent as well as occasional exposure and type of work, indoors and outdoors. They are not applicable to specific effects associated with certain meteorological phenomena (e.g. precipitation), which are assessed by other methods.

ISO 11399:1995

Ergonomics of the thermal environment - Principles and application of relevant International Standards

Purpose is to specify information which will allow the correct, effective and practical use of International Standards concerned with the ergonomics of the thermal environment. Describes the underlying principles concerning the ergonomics of the thermal environment.

ISO 12894:2001

Ergonomics of the thermal environment -- Medical supervision of individuals exposed to extreme hot or cold environments

This International Standard provides advice to those concerned with the safety of human exposures to extreme hot or cold thermal environments. Extreme thermal environments are those which result in a high rate of heat gain or loss by the body. A precise definition of such environments cannot easily be given, as the change in body heat storage depends on clothing and activity as well as the parameters of the climatic environment. As a guide, the boundaries of extreme environments might be considered to be as follows: for hot environments, a wet bulb globe temperature of 25 C; for cold environments an air temperature of 0 C or below. Extreme environments can only be tolerated for limited periods of time before a risk of ill health results. Control measures are necessary to ensure the safety of those so exposed, one of which is the provision of appropriate medical supervision prior to and during exposures. This International Standard is intended to assist those with responsibility for such exposures to reach decisions about the appropriate level of medical supervision in different situations. This International Standard should be read and used in the context of other relevant guidance and legislation. This guidance is applicable to laboratory and occupational exposures to extreme environments. In either case an assessment should be made of the expected thermal stress on the individual, but the detailed arrangements for medical supervision will differ. Control of occupational exposures must also satisfy national health and safety legislation. The laboratory or climatic chamber studies for which this International Standard will be relevant include those in which people may be exposed to high or low ambient conditions or local heating or cooling. Studies may, for example, investigate physiological or psychophysical responses to the environment or the benefit of clothing or other protective equipment. Scientific investigations and demonstrations for teaching purposes are included in the scope. In some countries, such studies are subject to specific legislation and, in all cases, experimental exposures should be conducted in the context of accepted ethical criteria as detailed in relevant national and international statements (see informative annex A and the bibliography). Extremes of environment may be only one component of the total physiological stress imposed in a study. In such cases, appropriate advice must also be obtained with regard to any medical supervision required prior to exposure to the other stressors involved, for example whole body vibration. In some cases, ergonomic investigations are conducted in the field, for example, to document the physiological stress of particular occupations. If the overall stress of the task is increased as a result of the proposed study, this International Standard will be relevant. This International Standard does not apply to the use of hypo or hyper thermia in the course of medical investigation or treatment.

ISO 13732-1:2006

Ergonomics of the thermal environment - Methods for the assessment of human responses to contact with surfaces - Part 1: Hot surfaces

ISO 15536-1:2006 provides temperature threshold values for burns that occur when human skin is in contact with a hot solid surface. It also describes methods for the assessment of the risks of burning, when humans could or might touch hot surfaces with their unprotected skin. In addition, ISO 13732-1:2006 gives guidance for cases where it is necessary to specify temperature limit values for hot surfaces, but does not set surface temperature limit values. ISO 13732-1:2006 deals with contact periods of 0,5 s and longer. It is applicable to contact when the surface temperature is essentially maintained during the contact. It is not applicable if a large area of the skin (approximately 10 % or more of the skin of the whole body) can be in contact with the hot surface. Neither does it apply to skin contact of more than 10 % of the head or contact which could result in burns of vital areas of the face. ISO 13732-1:2006 is applicable to the hot surfaces of all kind of objects: equipment, products, buildings, natural objects, etc. It is applicable to hot surfaces of products that may be touched by healthy adults, children, elderly people and also by people with physical disabilities. For the purposes of simplification, it mentions only products; nevertheless, it applies to all other objects as well. It is applicable to products used in any environment, e.g. in the workplace, in the home. It does not provide data for the protection against discomfort or pain.

ISO 13732-3:2005

Ergonomics of the thermal environment - Methods for the assessment of human responses to contact with surfaces - Part 3: Cold surfaces

ISO 13732-3:2005 provides methods for the assessment of the risk of cold injury and other adverse effects when a cold surface is touched by bare-hand/finger skin. It provides ergonomics data for establishing temperature limit values for cold solid surfaces. The values established can be used in the development of special standards, where surface temperature limit values are required. Its data are applicable to all fields where cold solid surfaces cause a risk of acute effects: pain, numbness and frostbite, and are not limited to the hands but can be applied in general to the healthy human skin of male and female adults.

ISO/TS 13732-2:2001

Ergonomics of the thermal environment -- Methods for the assessment of human responses to contact with surfaces -- Part 2: Human contact with surfaces at moderate temperature

This part of ISO/TS 13732 presents principles and methods for predicting the thermal sensation and degree of discomfort for people where parts of the body are in contact with solid surfaces at moderate surface temperatures (approximately 10 C to 40 C). It deals with the thermal sensation for contacts of the hand, foot and for the sitting position on the floor.

ISO 15265:2004

Ergonomics of the thermal environment - Risk assessment strategy for the prevention of stress or discomfort in thermal working conditions

ISO 15265:2004 describes a strategy for assessing and interpreting the risk of physiological constraints, or of discomfort, while working in a given climatic environment. It is applicable in any working situation with steady or varying conditions of the climate, metabolic rate or clothing. ISO 15265:2004 does not describe a single procedure, but a strategy in three stages that can be used successively to gain deeper insight in the working conditions, as it is needed to draw the most appropriate conclusions about the risk involved and identify the best control and prevention measures. It is definitely oriented towards the prevention and/or control of these working problems in the heat or cold. The risk of heat or cold disorders and/or discomfort is therefore assessed only to the extent that it is required to reach this goal.

ISO 15743:2008

Ergonomics of the thermal environment - Cold workplaces - Risk assessment and management

ISO 15743:2008 presents a strategy and practical tools for assessing and managing cold risk in the workplace, and includes: models and methods for cold risk assessment and management; a checklist for identifying cold-related problems at work; a model, method and questionnaire intended for use by occupational health care professionals in identifying those individuals with symptoms that increase their cold sensitivity and, with the aid of such identification, offering optimal guidance and instructions for individual cold protection; guidelines on how to apply thermal standards and other validated scientific methods when assessing cold related risks; a practical example from cold work. It is applicable to both indoor and outdoor work situations indoor work includes work done inside vehicles, outdoor work both inland and offshore work but is not applicable to diving situations or other types of work performed underwater.

ISO 7726:1998

Ergonomics of the thermal environment - Instruments for measuring physical quantities

This International Standard specifies the minimum characteristics of instruments for measuring physical quantities characterizing an environment as well as the methods for measuring the physical quantities of this environment. It does not aim to define an overall index of comfort or thermal stress but simply to standardize the process of recording information leading to the determination of such indices. Other International Standards give details of the methods making use of the information obtained in accordance with this standard. This International Standard is used as a reference when establishing specifications for manufacturers and users of instruments for measuring the physical quantities of the environment; a written contract between two parties for the measurement of these quantities. It applies to the influence of hot, moderate, comfortable or cold environments on people.

ISO 7730:2005

Ergonomics of the thermal environment - Analytical determination and interpretation of thermal comfort using calculation of the PMV and PPD indices and local thermal comfort criteria

ISO 7730:2005 presents methods for predicting the general thermal sensation and degree of discomfort (thermal dissatisfaction) of people exposed to moderate thermal environments. It enables the analytical determination and interpretation of thermal comfort using calculation of PMV (predicted mean vote) and PPD (predicted percentage of dissatisfied) and local thermal comfort, giving the environmental conditions considered acceptable for general thermal comfort as well as those representing local discomfort.

ISO 7933:2004

Ergonomics of the thermal environment - Analytical determination and interpretation of heat stress using calculation of the predicted heat strain

ISO 7933:2004 specifies a method for the analytical evaluation and interpretation of the thermal stress experienced by a subject in a hot environment. It describes a method for predicting the sweat rate and the internal core temperature that the human body will develop in response to the working conditions. The various terms used in this prediction model, and in particular in the heat balance, show the influence of the different physical parameters of the environment on the thermal stress experienced by the subject. In this way, this International Standard makes it possible to determine which parameter or group of parameters should be modified, and to what extent, in order to reduce the risk of physiological strains. The main objectives of ISO 7933:2004 are the following: the evaluation of the thermal stress in conditions likely to lead to excessive core temperature increase or water loss for the standard subject; the determination of exposure times with which the physiological strain is acceptable (no physical damage is to be expected). In the context of this prediction mode, these exposure times are called maximum allowable exposure times . ISO 7933:2004 does not predict the physiological response of individual subjects, but only considers standard subjects in good health and fit for the work they perform. It is therefore intended to be used by ergonomists, industrial hygienists, etc., to evaluate working conditions.

ISO 8996:2021

Ergonomics of the thermal environment - Determination of metabolic rate

This document specifies different methods for the determination of metabolic rate in the context of ergonomics of the thermal working environment. It can also be used for other applications, e.g. the assessment of working practices, the energetic cost of specific jobs or sport activities and the total energy cost of an activity. The methods are classified in four levels of increasing accuracy: level 1, Screening, with a table giving examples of activities with low, moderate and high metabolic rates; level 2, Observation, where the metabolic rate is estimated by a time and motion study; level 3, Analysis, where the metabolic rate is estimated from heart rate recordings or accelerometers measurements; and level 4, Expertise, where more sophisticated techniques are described. The procedure to put into practice these methods is presented and the uncertainties are discussed.

ISO 9920:2007

Ergonomics of the thermal environment - Estimation of thermal insulation and water vapour resistance of a clothing ensemble

ISO 9920:2007 specifies methods for estimating the thermal characteristics (resistance to dry heat loss and evaporative heat loss) in steady-state conditions for a clothing ensemble based on values for known garments, ensembles and textiles. It examines the influence of body movement and air penetration on the thermal insulation and water vapour resistance. It does not deal with other effects of clothing, such as adsorption of water, buffering or tactile comfort, take into account the influence of rain and snow on the thermal characteristics, consider special protective clothing (water-cooled suits, ventilated suits, heated clothing), or deal with the separate insulation on different parts of the body and discomfort due to the asymmetry of a clothing ensemble.

ISO 9886:2004

Ergonomics - Evaluation of thermal strain by physiological measurements

ISO 9886:2004 describes methods for measuring and interpreting the following physiological parameters: body core temperature; skin temperatures; heart rate; body-mass loss.