Control of Substances Hazardous to Health (COSHH) - COSHH
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Control of Substances Hazardous to Health (COSHH)
This website provides practical advice and Guidance on the Control of Substances Hazardous to Health Regulations 2002. You can find information on what the law requires, advice on completing COSHH assessments.
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HSE aims to reduce work-related death, injury and ill health.Heat stress - Temperature - HSE
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Heat stress
Heat stress
This page tells you about the risks of overheating when
working in hot conditions and gives practical guidance on how to avoid it. It
does not address issues of
in the workplace.
In many jobs heat stress is an issue all year round (such as
bakeries, compressed air tunnels, foundries and smelting operations), but this
information is also applicable during the hot summer months where there may be
an increased risk of heat stress for some people.
Heat stress occurs when the body’s means of controlling its
internal temperature starts to fail. As well as air temperature, factors such
as work rate, humidity and clothing worn while working may lead to heat stress.
Therefore it may not be obvious to someone passing through the workplace that
there is a risk of heat stress.
You and your employees must be aware of how to work safely
in heat, the factors that can lead to heat stress, and how to reduce the risk
of it occurring.
How does the body react to heat?
The body reacts to heat by increasing the blood flow to the
skin’s surface, and by sweating. This results in cooling as sweat evaporates
from the body’s surface and heat is carried to the surface of the body from
within by the increased blood flow. Heat can also be lost by radiation and
convection from the body’s surface.
Typical example of a heat stress situation
Someone wearing protective clothing and performing heavy
work in hot and humid conditions could be at risk of heat stress because:
sweat evaporation is restricted by the type of
clothing and the humidity of the environment
heat will be produced within the body due to the
work rate and, if insufficient heat is lost, core body temperature will rise
as core body temperature rises the body reacts
by increasing the amount of sweat produced, which may lead to dehydration
heart rate also increases which puts additional
strain on the body
if the body is gaining more heat than it can
lose the deep body temperature will continue to rise
eventually it reaches a point when the body’s
control mechanism itself starts to fail
The symptoms will worsen the longer someone remains working
in the same conditions.
What are the effects of heat stress?
Heat stress can affect individuals in different ways, and
some people are more susceptible to it than others.
Typical symptoms are:
an inability to concentrate
muscle cramps
severe thirst - a late symptom of heat stress
heat exhaustion - fatigue, giddiness, nausea,
headache, moist skin
heat stroke - hot dry skin, confusion,
convulsions and eventual loss of consciousness. This is the most severe
disorder and can result in death if not detected at an early stage
Where does heat stress occur?
Examples of workplaces where people might suffer from heat
stress because of the hot environment created by the process, or restricted
spaces are:
glass and rubber manufacturing plants
compressed air tunnels
conventional and nuclear power plants
foundries and smelting operations
brick-firing and ceramics plants
boiler rooms
bakeries and catering kitchens
In these industries working in the heat may be the norm. For
others it will be encountered more irregularly depending on the type of work
being done and changes in the working environment, eg seasonal changes in
outside air temperature can be a significant contributor to heat stress.
What do I need to do about heat stress?
Over time people adapt to hot
conditions by sweating more, and by changing their behaviour to try and cool
down, eg removing clothing, taking cool drinks, fanning themselves, sitting in the
shade or a cool area, and/or reducing their work rate. However, in many work
situations such behavioural changes may not be possible, eg during asbestos
Where there is a possibility of
heat stress occurring you will need to carry out a risk assessment.
provides advice on how
to carry out a risk assessment.
For specific advice on how to record the
findings of your heat stress risk assessment and identifying the heat stress risks you need to control use the
What do I need to look at in a risk assessment?
When carrying out a risk assessment, the major factors you
need to consider are:
work rate - the harder someone works the greater the amount of body
heat generated
working climate - this includes air temperature, humidity, air
movement and effects of working near a heat source
employee clothing and respiratory protective equipment - may impair
the efficiency of sweating and other means of te employee’s
age, build and medical factors - may affect an individual’s tolerance
Firstly, you should talk to the
workers involved (and their safety representatives), to see whether they are
suffering early signs of heat stress. If it seems likely that there is a
problem, you may need to consult with people who are more experienced in
determining the risk from hot environments, eg occupational hygienists, nurses
or doctors.
How can I reduce the risks?
Remove or reduce the sources of heat where possible:
the temperature
Control the temperature using engineering solutions eg:
change the processes
use fans or air conditioning
use physical barriers that reduce exposure to
radiant heat
mechanical aids
Provide mechanical aids where possible to reduce the work
rate. Regulate the length of exposure to hot environments by:
allowing employees to enter only when the
temperature is below a set level or at cooler times of the day
specify how long your employees should work in situations where there is a risk
providing periodic rest breaks and rest
facilities in cooler conditions
dehydration
Working in a hot environment causes sweating which helps
keep people cool but means losing vital water that must be replaced. Provide
cool water in the workplace and encourage workers to drink it frequently in
small amounts before, during (this is not possible in some situations eg
respiratory protective equipment use or asbestos removal) and after working.
personal protective equipment
Specialised personal protective clothing is available which
incorporates, for example, personal cooling systems or breathable fabrics.
This may help protect workers in certain hot environments.
Protective clothing or respiratory protective equipment is often provided to protect
from a hazard at work eg asbestos. This type of equipment, while protecting the
employee from this hazard may expose the employee to heat stress.
training for your workers, especially new and young employees
telling them about the risks of heat stress associated with their work, what
symptoms to look out for, safe working practices and emergency procedures.
Acclimatisation
workers to acclimatise to their environment and identify which
workers are acclimatised/assessed as fit to work in hot conditions.
Identify who is at risk
employees who are more susceptible to heat stress either
because of an illness/condition or medication that may encourage the early
onset of heat stress, eg those with heart conditions.
Advice may be needed from an occupational health
professional or medical practitioner. Your
risk assessment should already address risks to pregnant employees, but you may
choose to review it when an employee tells you she is pregnant, to help you
decide if you need to do any&more to control the risks.
Monitor health
the health of workers at risk. Where it is considered that a
residual risk remains after implementing as many control measures as
practicable, you may need to monitor the health of workers exposed to the risk.
You should then seek advice from occupational health professionals with a good
working knowledge of the risks associated with working in heat stress
situations.
HSE aims to reduce work-related death, injury and ill health.COSHH basics - COSHH
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COSHH basics
What is COSHH?
COSHH is the law that requires employers to control substances that are hazardous to health. You can prevent
or reduce workers exposure to hazardous substances by:
finding out what th
deciding how to prevent harm to health ();
providing control measures to reduce
keeping all control measures in good
providing information, instruction and
training for
providing monitoring and health surveillance
planning for emergencies.
Most businesses use
substances, or products that are mixtures of substances. Some processes create substances. These could cause harm to employees,
contractors and other people.
Sometimes substances are easily recognised
as harmful. Common substances such as paint, bleach or dust from natural
materials may also be harmful.
HSE aims to reduce work-related death, injury and ill health.}