This document summarizes methods for assessing heat stress. It discusses factors that contribute to heat stress like high humidity, protective clothing, and heavy work. Common areas where heat stress occurs are mines, boiler rooms, and foundries. Risk assessment considers work rate, climate, clothing, and worker health. Assessment methods include the WBGT index, which measures wet bulb, globe, and air temperatures, and checklists that evaluate multiple parameters. Monitoring worker physiology is also used when other methods can't be implemented. The goal is to efficiently design interventions to reduce heat stress risks.

1. CE1020- PROJECT
TOPIC: HEAT STRESS ASSESSMENT
METHODS
NAME: ARAVIND.R
ROLL NO: CE14B006

2.  When the body loses its ability to control its internal
temperature it is called as Heat stress.
 As well as work rate ,humidity, clothing worn may
lead to heat stress.
 So it is very necessary to know by every individual to
know how to work safely in the heated environment
to avoid the dangers of heat stress.
WHAT IS HEAT STRESS?

3. 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, deep body temperature
will rise.
 As deep body temperature rises the body reacts by
increasing the amount of sweat produced , which may lead
to dehydration.
EXAMPLE OF HEAT STRESS
SITUATION

4.  Mines
 Compressed air tunnels
 Boiler rooms
 Bakeries and Kitchen
 Brick firing and Ceramics plants
 Nuclear power plants
 Foundries and smelting operations
Generally the places mentioned above have the great deal
of chances of occurring Heat stress. Hence we need to do
stress assessment by various method.
WHERE DOES HEAT STRESS
OCCURS?

5. When we are carrying out risk assessment we need to
consider major factors like,
1. Working rate
2. Working climate
3. Worker clothing
4. Protective equipment
5. To know the initial health conditions of Workers
The above mentioned factors are the main factors involving
for heat risk assessment.
RISK ASSESSMENT

6. The strategy of calculating the heat stress is classified
into three stages namely
1. Exploratory stage
2. Development and design stage
3. Evaluation stage
The three mentioned above stages has advantages
,disadvantages and some sort of complexity in it.
HEAT STRESS ASSESSMENT METHOD

7. The main objectives of this stage are
1. To provide a practical example of a heat stress assessment in
industry.
2. To investigate and describe the task of assessing the risk of
heat stress using current heat stress standards.
Some of important methods used are
Literature review
Informal interviews
Hierarchical task analysis
EXPLORATORY STAGE

8. USABILITY
METHODS
ADVANTAGES DISADVANTAGES
Heuristic
Evaluation
• Finds individual
usability methods.
• Can address
expert issues
• Does not use real
users
• May not relate
with their needs
Interviews • In depth probing • Time consuming
• Difficulty in
analyse data
Group
Discussions
• Group ideas
• Spontaneous
conclusions
• Difficult and time
taking to analyse
Questionnaires • Easy to repeat • Care to prevent
misunderstanding

9. TOOLS USED IN ASSESSMENT
Heat stress assessment indices such as
1. WBGT index (Wet Bulb Globe temperature)
2. ACGIH TLV index (American conference of
governmental industrial hygienists).
3. SWreq is used if WBGT values are exceeded.

10. This is one of very effective methods ,
It comprises of 3 types of temperature
 Natural wet bulb temperature
 Global temperature
 Air temperature
In this method we will know all environmental measures . Then we will
consider the Air Movement and working rate of acclimatized worker and his
metabolic rate.
The WBGT obtained value is compared with standards with the information
of air movement and working rate of acclimatized worker.
If the measured value of WBGT is less than that of reference value then we
can conclude that heat stress is not a problem in that environment.
But there are disadvantages too!!
WBGT INDEX

11. WBGT CALCULATION

12. There is a way in which heat stress can be assessed in
quantitative way. The way is Heat Stress Assessment
checklist ,this a sheet which contains various
parameters such as temperature ,humidity , heat
radiation, Air movement, Workload, Acclimatization and
clothing.
We have to answer various questions inside the
divisions at the end we use all answers for analysis. With
the data analysed we will predict the heat stress in
quantitative way and will derive into conclusions.
ASSESSMENT CHECKLIST

13. It is better than exploratory stage as it prioritise the
various factors and give them importance accordingly.
Means it gives the score accordingly to the level of
effects by various factors which causes Heat Stress.
In this two main things are
1. Severity
2. Consequences
The above mentioned things are important as it clearly
decides the necessary requirements that can prevent
the adverse effects of Heat Stress risk.
DESIGN AND DEVELOPMENT STAGE

14. SEVERITY AND CONSEQUENCES

15. Two methods are implemented for calculating clothing
insulation values
1. Estimate the insulation values from standard tables
2. Calculating insulation value from actually what they
worn. It depends on material and surface area of the
clothing.
This helps in quantitative risk assessment. This can be
used in designing the cloth material for the workers to
reduce their heat stress. But first method is preferable
as it gives direct values but it is material specific.
CLOTHING INSULATION VALUES

16. It is used when there is no other alternatives cannot be implemented in
practicality that is levels are more than parameters of heat stress index.
It involves various needs that has to take care by employer. This method
has very specific and accurate since it deals with each and every
workers.
1. All measuring equipment and transmission equipment should be
calibrated properly.
2. Care should be taken in evacuation time, emergency procedures.
3. Care should be taken in devices and system such that they will not
affect the ability of rapid evacuation etc…
PHYSIOLOGICAL MONITORING

17. Hence we can conclude by giving overall outlook .
Methods are implemented following basis.
1. Basic assessment operation
2. Generic strategy
3. Presentation of information
4. Group discussions and interviews
The above four things are necessary for implementing a
method by going through all the steps above in order to
make efficient design to reduce heat stress.
CONCLUSIONS

18. As a Civil Engineer we have to care of many parameters
that creates problems to the users in very effective,
simple and cost effective ways ....
THANK YOU…..