ISO 8025:2024

International
Standard
ISO 8025
First edition
Ergonomics of the thermal
2024-01
environment — Management
of working conditions in hot
environments
Ergonomie de l'environnement thermique — Gestion des
conditions de travail dans les environnements chauds
Reference number
© ISO 2024
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ii
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms, definitions and symbols . 1
3.1 Terms and definitions .1
3.2 Symbols and abbreviated terms .2
4 Classification of the working situations in hot environments . 2
4.1 General .2
4.2 Risk management system .3
4.3 Exposure assessment and prevention procedure .3
4.3.1 General .3
4.3.2 Stage 1, screening .4
4.3.3 Stage 2, observation .5
4.3.4 Stage 3, analysis .5
4.3.5 Thermal exposure form (TEF) of the work situation .6
5 Control measures . 7
5.1 Work organization.7
5.2 Air temperature .7
5.3 Air humidity .7
5.4 Thermal radiation . .7
5.5 Air velocity .8
5.6 Clothing .8
5.7 Workload.8
5.8 Rehydration .9
5.9 Rest pauses and recovery .9
5.10 Acclimatization to heat .9
6 Information and training .10
7 Medical surveillance of people working in hot environments .11
7.1 General .11
7.2 Initial evaluation .11
7.2.1 General .11
7.3 Periodical evaluations . 12
7.4 Personal monitoring . 12
7.5 Information for workers . 12
7.6 Information to the employer . 13
8 Contact with hot surfaces .13
Annex A (informative) Datasheet for identifying working situations with heat-related problems
(stage 1, screening) . 14
Annex B (informative) Scoring scales for stage 2, observation .16
Annex C (informative) Metabolic rate .18
Annex D (informative) Thermal exposure form .21
Annex E (informative) Example of application of the heat stress assessment procedure .22
Bibliography .28

iii
Foreword
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This document was prepared by Technical Committee ISO/TC 159, Ergonomics, Subcommittee SC 5,
Ergonomics of the physical environment.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.

iv
Introduction
This document belongs to a group of thermal standards intended for use in the assessment and management
of work in hot environments.
Several outdoor and indoor lines of industries, commerce and occupations involve substantial exposure,
where individuals can be exposed to high temperatures, humidity and/or thermal radiation. Working
in such hot environments can lead to several adverse effects on human performance and health, such as
thermal discomfort, increased strain, decreased performance and heat-related disorders. Heat can also
interfere with several other factors in the workplace, modifying or aggravating the risk of common hazards
and increasing the risk of heat-associated disorders. In addition, skin contact with hot surfaces can lead to
burns.
Due to the negative impact of heat on human health and performance, as well as on work productivity,
quality and safety, it is necessary to consider a comprehensive strategy of risk assessment and management
practices.
While other standards have described specific indices to be used to assess the hot work environment and
the potential physiological consequences, this document describes the methods and practices for organizing
the management of these work environments and the supervision of the exposed persons.
The choice of when to use the methods described in this document is at the discretion of the persons
responsible for occupational safety and/or health.

v
International Standard ISO 8025:2024(en)
Ergonomics of the thermal environment — Management of
working conditions in hot environments
1 Scope
This document adopts an approach where actions, particularly control measures and medical supervision,
are specified as a function of the class of severity of the potential effects. It provides instructions for
appropriate management practices for hot workplaces and describes:
— a procedure for managing work in hot environments;
— guidelines on how to apply the different International Standards in the field of thermal environments
when assessing heat-related risks;
— guidelines to organize the medical supervision of the people working in hot environments;
— information for instructing the persons working in hot environments;
— an example of assessment of a hot working situation.
The procedure described in this document aims to anticipate the problems related to work in warm to
hot environments by classifying the different work situations according to their potential health effects,
informing the persons concerned (workers and management) of the seriousness of these effects, planning
appropriate measures to be implemented to prevent these effects and providing medical surveillance of
exposed persons.
This document supports good occupational safety and health practices and is applicable to both indoor and
outdoor work situations.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes
requirements of this document. For dated references, only the edition cited applies. For undated references,
the latest edition of the referenced document (including any amendments) applies.
ISO 15265:2004, Ergonomics of the thermal environment — Risk assessment strategy for the prevention of
stress or discomfort in thermal working conditions
3 Terms, definitions and symbols
3.1 Terms and definitions
No terms and definitions are listed in this document.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/

3.2 Symbols and abbreviated terms
Symbol or Definition Units
abbreviated
term
D duration limit of exposure min
lim
EC exposure class of a work situation
I static (or basic) clothing thermal insulation clo
cl
M metabolic rate W
p partial water vapour pressure kPa
a
PHS predicted heat strain
PMV predicted mean vote
PPD predicted percentage of dissatisfied %
RH relative humidity %
t air temperature °C
a
t globe temperature °C
g
TEF thermal exposure form of a work situation
−1
v air velocity m·s
a
WBGT wet bulb globe temperature °C
WBGTlim limit of the WBGT index as a function of metabolic rate °C
4 Classification of the working situations in hot environments
4.1 General
The nature and the urgency of the control measures to improve and eliminate a working situation where
a heat-related health problem could occur depend upon the severity of this problem. Table 1 defines the
six ECs and the classification criteria, according to the PMV value and the D of the thermal condition. As
lim
defined in ISO 7933, D is the duration of exposure after which either the total sweating exceeds 3 % of the
lim
body weight of the average worker or the core temperature reaches 38 °C.
Table 1 — Definition of the six ECs for hot working situations
EC Definition Criteria
1)
1 Thermal comfort as defined in ISO 7730 −0,7 < PMV < 0,7
2 Light thermal discomfort 0,7 ≤ PMV < 1,7
3 Strong thermal discomfort 1,7 ≤ PMV and D ≥ 480 min
lim
4 Thermal constraint in the long term 120 < D < 480 min
lim
5 Thermal constraint in the short term 30 < D ≤ 120 min
lim
6 Immediate thermal constraint D ≤ 30 min
lim
This document describes the procedure to identify as soon as possible the EC of a given work environment,
select accordingly the optimal control measures to eliminate or minimize the exposure, organize the
working situation in consequence and protect adequately the exposed persons.
1) Under preparation. Stage at the time of publication: ISO/DIS 7730:2024.

4.2 Risk management system
The heat risk management model shall be fully integrated into the occupational health and safety
management system and practices of the organization, to ensure the implementation and continuance of the
activities.
NOTE This kind of system can be established according to, for example, ISO 45001, which was prepared to be
compatible with ISO 9001 for quality management systems and ISO 14001 for environmental management systems.
4.3 Exposure assessment and prevention procedure
4.3.1 General
The exposure assessment procedure follows the principles presented in ISO 15265, with the addition of
an initial stage for the recognition of the situations where a heat-related health problem could occur. The
procedure therefore includes four stages and is illustrated in Figure 1.
— Stage 1, screening: where the working situations that are causing or are likely to lead to heat stress
exposures are identified and listed.
— Stage 2, observation: where the working situations identified in stage 1 are reviewed qualitatively
to determine the simple and straightforward measures to be implemented to reduce the class of the
working situation to EC 1, or at least EC 2.
A decision is made to perform a further analysis if the problem is neither eliminated nor sufficiently
reduced, or whenever it is uncertain whether the preventive actions will be or have been sufficient to
guarantee the persons' health and safety.
— Stage 3, analysis: where quantitative evaluations are made of the parameters characterizing the working
situations and the thermal indices defined in ISO 7730 (PMV and PPD), ISO 7243 (WBGT) and ISO 7933
(PHS) are computed. Additional control or organisational measures are determined and their effects to
improve the working situations are evaluated.
It is anticipated that most common problems of work in hot situations can be managed using the methods
and procedures in stages 1 to 3. For unusual or peculiar work circumstances, a further expertise stage
is conducted (stage 4).
— Stage 4, expertise: will usually deal with highly complex thermal working circumstances and require
sophisticated or specific measurements. This stage is conducted by the same persons as stage 3, with the
additional assistance of highly specialized experts. The approach and techniques that are required will
vary according to the nature of the problem and are within the responsibility of the intervening experts.
This stage will therefore not be further discussed in this document.

Figure 1 — Model for heat risk assessment in workplaces
4.3.2 Stage 1, screening
The screening datasheet presented in Annex A can be used to conduct this screening to identify the climatic
working situations that need to be assessed, as these can lead to thermal problems for the persons exposed.
This stage is performed in anticipation of the problems by a qualified health and safety professional.
The procedure is as follows:
a) Consider the work situation as a whole: before using the checklist, review the different exposure
circumstances that can exist (e.g. day, night, season, production demands).
b) Categorize these work circumstances and choose to study the circumstance(s) that is (are) most
thermally problematic.
c) Complete the data sheet for each selected work circumstance by checking separately each aspect listed
and retaining the options that best match.
d) Collect the opinion of the workers involved in the activity.
e) Record any information related to each aspect.
At the end of this stage, it is decided:
— whether the working situation is definitely of EC 1 or 2, in which case the procedure comes to an end;
— whether additional information needs to be collected to reach a professional decision, in which case the
procedure of evaluation proceeds to stage 2.
This screening data sheet shall be periodically reviewed in one of the following instances:
— at least once a year, preferably before the hot season in the case of seasonal variations;
— when the work activity has changed substantially;
— when the work environment has changed significantly.

4.3.3 Stage 2, observation
It is recommended that this observation study be performed by the health and safety professional who
prepared the screening datasheet, with the close participation of the people directly exposed to these
situations, as they know best all the variants of the work activity and the possibilities of improvement that
can be achieved locally.
It consists of examining, for each work situation identified in stage 1, the reasons why the situation deviates
from comfort and what can be done about air temperature, humidity, heat radiation, ventilation, workload,
clothing and work organization in general to minimize or eliminate any thermal risk.
The procedure at stage 2, observation, shall be in accordance with ISO 15265 as follows:
— Assess the situation for each of the seven parameters separately, using the rating scales described in
Annex B, Table B.1.
— Record the general opinion of the workers.
— Identify with them the necessary measures to eliminate or at least reduce risks and determine how and
when to implement them.
— Determine, if needed, the short-term measures to be taken, for example drinks, recovery periods, work
organization, adaptation of work clothing.
— Assess, based on the scales in Annex B, the expected ratings in the future condition, when the considered
prevention measures will be implemented.
If the future condition is predicted to be of EC 1 or 2, then the procedure comes to an end.
If it is not the case or the future class proves difficult to estimate, this indicates the need to carry out an in-
depth analysis to identify more precisely the factors on which to act through additional control measures.
Annex C describes the methods for assessing work metabolism and, in particular by means of Table C.1,
makes it possible to easily determine whether the workload is light, moderate, heavy or very heavy.
4.3.4 Stage 3, analysis
It is recommended that this analysis be conducted by occupational health and safety professionals qualified
concerning the measurements and evaluation of the basic parameters, the use of different standards and the
estimation of the risks.
The assessment of the exposure class of a work situation requires an evaluation of:
— the air temperature (t , in °C) by any suitable device whose sensor is protected against radiation;
a
— its humidity, usually the relative humidity (RH) in %;
— the radiant heat, usually by measuring the temperature of the black globe, t , in °C;
g
— the air velocity, in m/s, using a hot wire anemometer or equivalent;
— the energy expenditure related to work, i.e. the metabolic rate in watts, estimated or measured using
one of the methods at levels 2 to 4 described in ISO 8996 and briefly presented in Annex C;
— the clothing thermal insulation I , in clo, estimated or measured based on ISO 9920.
cl
The measuring instruments fulfil the requirement of ISO 7726 for the measurement of air temperature,
air humidity, air velocity and thermal radiation, and of ISO 7243 for the evaluation of the natural wet bulb
temperature. They are calibrated according to manufacturer recommendations.
ISO 7726 describes the procedures to be used to evaluate as accurately as possible the exposure of a given
person in a given environment at a given time. This is required for instance in cases of dispute in the
interpretation of data. In the context of this document, the objective being the definition of the exposure

class of a work situation for a group of persons in certain climatic and production circumstances and of
the best prevention measures, the same degree of accuracy is not required and the procedure, detailed as
follows, is less exacting:
— The measurements are performed during the hottest periods of the exposure, the day and the year or
during particularly heavy work phases (e.g. production peaks, machine breakdowns) or when wearing
less suitable clothing.
— These environmental measurements are carried out at the place where the workers are exposed or, if
this is not feasible, at the place where they would be exposed to the thermal environment, or as close as
possible to this place, at 110 cm above the ground if the workers are standing and at 60 cm if seated.
— When parameters in the space surrounding the persons are not homogeneous, measurements are made
at the work position where the parameters are estimated to be the highest, for the exposure class to
characterize the worst possible situation.
— When the exposed person changes work location between areas with different environmental
characteristics, measurements are made in each area and the sequence of time periods spent by the
operator in the different areas is recorded. If the duration of stay in the second environment is short (less
than 5 min) and the environmental parameters do not vary greatly (less than two times the required
accuracy according to ISO 7726 for the respective parameters) from the values of the previous period,
the two periods together can be analysed using the mean parameters obtained by a time-weighted
average of the individual values. If these conditions are not met, the work situations in the different
environments are analysed separately.
— Similarly, if the workload varies in the short term (periods of less than 5 min), a valid estimate of the
mean parameters is obtained by a time-weighted average of the individual values. If this condition is not
met, the different work situations are analysed separately.
The evaluation of the exposure class is done by calculating the PMV-PPD indices (ISO 7730) and from the
evolutions of water loss and central body temperature predicted by the predicted heat strain (PHS) model
(ISO 7933). Optionally, the WBGT index (ISO 7243) is calculated. These evaluations are made using the
average weight and size of the workers concerned and considering they are not acclimatized.
NOTE Using the temperature of the black globe, t , in °C, will overestimate radiant heat if the person is working
g
outdoors under solar irradiation.
4.3.5 Thermal exposure form (TEF) of the work situation
At the end of the exposure assessment and prevention procedure, a thermal exposure form (TEF) is prepared
for each work situation. It includes:
— a detailed description of the work to be performed throughout the duration of the work cycle;
— the EC from 1 to 6, determined at the end of the assessment procedure;
— all planned and scheduled technical and organizational control measures decided based on the
recommendations set out in Clause 6;
— possible emergency and first aid procedures;
— the recommendations of the responsible healthcare provider regarding health requirements and
restrictions for working in that heat exposure situation.
An example of a TEF is given in Annex D.
An example of application of the first three stages of the strategy is presented in Annex E.

5 Control measures
5.1 Work organization
When possible, operations in high EC situations are shifted to cooler hours of the day (morning or evening,
possibly night-time) or during cooler periods of the year. Such operations can also be shifted to cooler
premises or with less stressful operations (lighter work).
This requires that the tasks that can be moved be previously identified and that some adjustments be
made to operational schedules. The provisional list of such operations is established from the maintenance
programme of hot equipment or from incidents that warranted urgent attention in the past.
5.2 Air temperature
Air temperature can be reduced in the following ways.
— Reduction of internal heat gains from sources in the workplace by:
— insulating hot fluid pipes, furnace walls, etc.;
— locally exhausting hot gases generated by the various equipment.
— Reduction of external heat gains through:
— opaque walls and roofs by:
— making the surfaces exposed to sun more reflective with appropriate building materials;
— using insulation materials;
— cooling;
— glass walls by:
— reducing the incident heat flux, considering the orientation of windows, horizontal canopies,
external blinds, etc.;
— using more reflective glass using, for example, special glazing;
— covering them with a translucent material opaque to infrared radiation.
5.3 Air humidity
Air humidity can be lowered in the following ways.
— Reduction of the internal gains by:
— locally exhausting the vapours released from internal sources;
— strictly controlling steam leaks wherever and whenever they occur.
— Reduction of external gains by:
— eliminating any rainwater (or watering) input;
— drying all wet products outside.
5.4 Thermal radiation
Thermal radiation can be lowered in the following ways.
— Reduction of the exposure to sunlight by providing, for example, curtains, blinds or screens, preferably
placed outside.
— Reduction of radiation from hot surfaces by:
— reducing the surface temperature by appropriate thermal insulation;
— making these surfaces smooth, shiny, using low-emissivity paint in order to reduce the emissivity
compared with rough and dull surfaces;
— interposing one of the following reflective physical barriers between the radiation sources and the
person:
— preferably plain, opaque and covered with a glossy material (aluminium);
— very fine wire mesh if it is necessary to keep a visual contact with the radiant surface.
5.5 Air velocity
The work zones should be ventilated to ensure conditions as near as possible to comfort.
The maximum speed to be considered to improve a situation of work for endurable continuous exposure is
−1 −1
1 m·s and ideally 0,5 m·s .
For occasional and short interventions in a very hot environment, ventilation at a higher speed can be
accepted by the person as long as it reduces the difficulty of the task to be performed. It will be uniform over
the surface of the body (preferably from the front) and at the most comfortable temperature possible. The
−1
maximum speed accepted is of the order of 5 m·s .
5.6 Clothing
From a thermal standpoint, the garment should ensure adequate protection against radiant heat while
allowing vapour diffusion.
If possible from a safety viewpoint, work clothes lighter and less insulating than the standard garments
shall be provided.
Search for special clothing to ensure protection against radiation, taking into consideration:
— the direction of radiation, allowing the use of clothing aluminized on one side only;
— the workload, because if physical activity is intense, evaporative needs are hampered by wearing the
garment.
Protective clothes, however, are a last resort, protection being generally obtained at the expense of thermal
comfort. The main disadvantages of these garments are their weight, the limitation of movement due to
their size or rigidity and especially the interference with the evaporation of sweat.
If protective clothing against non-thermal hazards has to be worn, most likely in situations of EC 5 and EC 6,
it is recommended that the use of personal cooling systems be considered. Such systems can comprise vests
or devices worn beneath the clothing which cool with ice or phase-change materials or by ventilation. Cool
and dry air could also possibly be blown into the workplace by means of a flexible tube.
The protective clothes shall be easily slipped over the usual work wear when the intervention in front of the
radiant source is intermittent.
5.7 Workload
The workload, and therefore the metabolic rate, can be lowered by making work easier and less tiring
through, in particular:
— mechanization of some operations;
— reduction of effort through using more appropriate tools;

— provision of tools with mechanical assistance;
— reduction of displacements;
— improvement of posture.
5.8 Rehydration
Rehydration is promoted to enable people to compensate for water loss caused by sweating. This can include:
— offering a selection of fresh drinks, such as still drinking water and non-carbonated and unsweetened
lemonade, and low-sugar electrolyte replenishing fluids;
— prohibition of any alcohol or beverages that could slow down rehydration;
— installation of cool water fountains (10 °C to 15 °C) close to work sites;
— provision of beverages with salt content when recommended by an occupational physician.
Depending on the EC of the work situation, short work breaks should be organized every 15 min to 20 min to
allow frequent drinking in small quantities (150 ml to 200 ml).
5.9 Rest pauses and recovery
If the work situation is EC 3 or EC 4, rest pauses can be organized with the possibility of rapid local cooling,
such as immersion of the hands or forearms in cool water (20 °C).
In the case of EC 5 or EC 6, recovery facilities are required. As the thermohygrometric conditions of the
recovery room play an important role, it is necessary to:
— locate this room close to the workplace to maximize its use;
— make the room thermally comfortable, taking account of the clothes worn by people when recovering.
5.10 Acclimatization to heat
Persons repeatedly working in hot environments develop an additional tolerance called acclimatization that
translates into earlier onset of sweating, greater sweat rate, more even distribution of sweat secretion on
the body surface, decreased ion concentration in sweat and, consequently, reduction of the core temperature
and heart rate.
This acclimatization is achieved by daily exposure for several hours to heat during the first five consecutive
normal days of exposure.
During this period, the exposure shall progress according to the following scheme.
— For persons familiar with the task: 50 % of normal hours the first day, 60 % on the second day, 80 % on
the third day and 100 % from the fourth day.
— For persons newly affected by the task: 20 % on the first day, possibly increasing by 20 % each successive
day.
During this period, the persons are supervised by someone trained to recognize early signs or symptoms of
heat-related illness.
Repeated full-day heat exposure without a staged acclimatization as described can lead to cumulative
fatigue and dehydration, with increasing strain, rather than having a beneficial acclimatization effect.
Acclimatization being rapidly reversible, a person not exposed to heat regularly for 15 days or more shall be
considered as unacclimatized and will therefore have to be subjected again to the acclimatization procedure
described previously.
6 Information and training
The employer develops a programme addressed at all persons before they begin to work in hot situations, as
well as at those responsible for the organization of these working situations, to inform them about the risks
linked to these situations and to train them to anticipate and reduce these risks.
All this information is made readily and freely available for all employees near the workstations concerned
by these measures.
The nature and extent of this information and training depend on the EC of the situation encountered, as
follows.
— For all situations:
— a description of the activities to be performed;
— a description of the EC of this work situation and of the nature and severity of the constraints to
which people are exposed.
— In addition, for situations EC 3 to EC 6:
— a description of the signs and symptoms of heat-related illness, such as heat cramps, heat exhaustion
and heat stroke, as well as the actions to be taken when such signs and symptoms occur;
— the need to regularly drink small amounts of cool water;
— non-occupational factors predisposed to heat problems, such as alcohol, drugs, obesity, excessive
thinness or fatigue;
— circumstances that contribute to reducing the duration (even to abstain from any exposure) and the
actions to be taken in the event of such circumstances:
— the first days following a return from leave or the resumption of work after disease;
— fever or the beginning of an infection;
— the use of anticholinergic substances (e.g. in nasal drops) to treat infections of the higher
respiratory tracts;
— a lack of complete recovery from any previous alcohol consumption;
— a feeling of great tiredness in the previous hours;
— working situations influencing the risk: clothing, effort, climatic parameters;
— technical measures to reduce the risks and how and when to implement them;
— the importance of acclimatization and the progressiveness of the exposure for unacclimatized
persons;
— the correct use and maintenance of heat-protective clothing and equipment.
— In addition, for situations EC 5 or EC 6:
— the risk of working alone isolated in the hottest areas;
— procedures to follow in the case of signs or symptoms of heat-related illness or of accident or incident,
such as first aid or persons to call;
— obligation and procedure to report, for individuals and their colleagues, any symptom of heat-related
illness and any accidents or incidents involving potentially high exposure levels;

— a surveillance system where each person exposed to heat is accompanied by another person or a
supervisor responsible for observing them at periodic intervals and signalling any symptoms of
heat-related illness.
7 Medical surveillance of people working in hot environments
7.1 General
Human responses to heat include complaints, a decrease in mental and physical performance, illness and
injuries. The responses show great individual variations and some individuals can suffer from much more
serious effects than others. To prevent this, it is essential to collect medical information from the individuals
potentially exposed to heat, evaluate their ability to sustain heat strain, identify those particularly at risk
and adopt for them special prevention measures. This medical supervision involves:
a) an initial evaluation before a person is exposed to a new working situation in a hot environment;
b) a periodical evaluation for people who remain exposed to the same working and environmental
situations of EC 3 to EC 6;
c) personal monitoring each time a person is working in a situation of EC 6.
7.2 Initial evaluation
7.2.1 General
This heat-related health assessment will differ according to the EC of the working situation (Figure 2).
Figure 2 — Initial evaluation of the fitness of a person for a given working situation with exposure
to heat, as a function of the EC
For working situations of EC 1 or EC 2: no special measures should be taken, and the general procedure
used in the organization to evaluate the fitness to work is adequate to protect all persons from heat-related
disorders.
In addition, for working situations in EC 3 to EC 6: a health assessment is done by a responsible healthcare
provider with the objective of identifying individuals having diseases or conditions that can exacerbate the
impact of heat or have heat-related personal working limitations.
If a final decision concerning the ability to work in the heat situation concerned cannot be taken based on
this assessment, a more thorough medical examination, possibly with clinical investigation, is required.
In addition, for working situations in EC 5 or EC 6: due to the severity of the physiological consequences
and the very large scattering of the human responses, a complete health assessment is performed by a

responsible healthcare provider with a thorough anamnesis as well as specific clinical investigations, as
recommended in ISO 12894:2001, Clause F.3.
As a result of this process, the responsible healthcare provider makes a decision to accept or not the employee
for the work situations envisaged and a medical fitness sheet is completed, recording all the possible heat-
related disorders and/or limitations of the person.
The content of the information and training given to the accepted persons is adapted as a function of the
work situation and the individual heat-related diseases or limitations to ensure their optimal health and
performance in the hot working situation.
7.3 Periodical evaluations
People particularly at risk are provided with a medical examination by a responsible healthcare provider
every year (or according to local regulations). This includes:
— persons exposed to work situations of EC 3 to EC 6;
— persons identified previously as presenting limitations for working in hot environments.
People who have experienced signs of heat-related disorders are subjected to a proper examination before
any further exposure to heat.
These examinations include an update of all information previously collected and, when required, specific
additional clinical investigations.
The medical fitness sheet is confirmed or amended for each person for their situations of exposure.
7.4 Personal monitoring
In the case of situations of EC 6, personal monitoring of the exposed persons is organized. This includes:
— the continuous observation of the person;
— the possibility of rapidly resorting to first aid (including means to rapidly cool the worker) and qualified
personnel in case of a problem.
Where possible, and particularly in the first days of occurrence of EC 6 situations, it is recommended that
the trend of physiological data of some of the workers most at
...