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EDITORIAL BOARD
R Parameswaran
W A Balakumaran
P Manoharan
G S Swaminathan
Printed at Sunitha Printers, Chennai – 600 002
VOL: 16 No. 3 JULY – SEPTEMBER 2017
QUARTERLY JOURNAL OF SAFETY ENGINEERS ASSOCIATION
G1, Vinoth Foundations, 95/5, Sundaramurthy Gramani Street, Virugambakkam, Chennai-600092.
Tel : 044-2377 4060 E-mail: [email protected] Website: www.seaindia.org
INDIAN SAFETY ENGINEERSEA (INDIA)
Inside... Page
From the Desk of President 1
Ayudha Pooja Celebration 2
Environmental Impacts of
Coal Power 3
Fall Protection Rescue Plan 4
Handling Electricity 6
How Firewall Barriers Prevent
Acetylene Tank Fires 7
Most Hazardous Wastes 8
Health Risk Assessment
(HRA) 9
CASE STUDY 13
Scalded by Hot Liquid from
Incinerator
Fall from Height While Climbing
Rope Ladder
IN THE NEWS 15
W H O New Director General
Dr Tedros Adhanom
Ghebreyesus First Address
XXI World Congress on Safety
and Health at Work: A Global
Forum for Prevention
(Regn No: 1391 / 2000)
[Registered under Societies Act, 1975]
FROM THE DESK OF PRESIDENT
Dear Safety Professionals,
This desk gives me an opportunity to express our desire and
decisions to our members.
91st Executive Committee meeting was held on August 22, 2017
at SEA India office.
As a follow up of AGM decision, it was decided to circulate this
quarterly Journal, Indian Safety Engineer in softcopy only from
this issue onwards. If you you wish to go back to hard copy, pl
send a mail to SEA India, [email protected] about
your request and it will be considered by the committee.
So far SEA India was engaged in organizing Professional
Development Programes, arranging Factory Visits both once in
a quarter, Publication of monthly Safety Alerts and Quarterly
Journals in addition to conducting Safety Professionals Meet once
in a year.
To enhance our services to our members, We are working for a
job portal which will fullfil the need of job seekers and also who
wants change of employment.
Ayudha Pooja was celebrated in SEA India office on Thursday,
28th September 2017. Most of the office bearers of SEA India
participated in the pooja celebration.
Arrangements are also being made for conducting a workshop
exclusively for construction people at Chennai during the month
of December 2017.
I once again request our members to send their suggestions/
ideas for further development and to increase our services to all
our safety professionals.
With Best Wishes,
R Parameswaran
President
SEA India
9444009819
2
AYUDHA POOJA CELEBRATION
Ayudha Pooja was celebrated on Thursday, September 28th 2017 at SEA India office.
Most of the SEA India office bearers participated in the Pooja Celebration.
REMINDER
Of late, Safety Alert by e-mail and Journal through post return to the sender. Hence, SEA
(India) members are requested to send their current postal address and active email ID
(personal) to us at the earliest to: [email protected]
Kind Attention of Members....SEA India wants to share the experience and innovative knowledge on Environment, Health and
Safety related topics among our safety professionals .
If any of our Members want to deliver talk on EHS topics, please contact our Secretary, SEA
(India) for utilizing their services in the ensuing professional development programs being conducted
once in every quarter.
Also if any of our members want to conduct implant training program in their factories , they can
contact our secretary for organizing such program at nominal cost.
Success stories in improving EHS system in your unit, interesting case studies which may be useful
to our members and safety alerts can be sent to our mail id for publication in this journal .
The source of information will not be disclosed in any form.
3
ENVIRONMENTAL IMPACTS OF COAL POWER
Coal Power plants are the source
of carbon dioxide (CO2)
emissions, the primary cause of
global warming.
Burning coal is also a leading
cause of smog, acid rain, and toxic
air pollution. Some emissions can
be significantly reduced with
readily available pollution control
technologies.
• Sulfur dioxide (SO2): Coal
plants are the leading source
of SO2 pollution, which takes
a major toll on public health,
including by contributing to
the formation of small acidic
particulates that can penetrate
into human lungs and be
absorbed by the bloodstream.
SO2 also causes acid rain,
which damages crops, forests,
and soils, and acidifies lakes
and streams. A typical
uncontrolled coal plant emits
14,100 tons of SO2 per year. A
typical coal plant with
emissions controls, including
flue gas desulfurization
(smokestack scrubbers), emits
7,000 tons of SO2 per year.
• Nitrogen oxides (NOx):
NOx pollution causes ground
level ozone, or smog, which
can burn lung tissue,
exacerbate asthma, and make
people more susceptible to
chronic respiratory diseases. A
typical uncontrolled coal plant
emits 10,300 tons of NOx per
year. A typical coal plant with
emissions controls, including
selective catalytic reduction
technology, emits 3,300 tons
of NOx per year.
• Particulate matter:
Particulate matter (also
referred to as soot or fly ash)
can cause chronic bronchitis,
aggravated asthma, and
premature death, as well as
haze obstructing visibility. A
typical uncontrolled plant
emits 500 tons of small
airborne particles each year.
Baghouses installed inside coal
plant smokestacks can capture
as much as 99 percent of the
particulates.
• Mercury: Coal plants are
responsible for the emission of
mercury, a toxic heavy metal
that causes brain damage and
heart problems. Just 1/70th of
a teaspoon of mercury
deposited on a 25-acre lake
can make the fish unsafe to
eat. A typical uncontrolled
coal plant emits approximately
170 pounds of mercury each
year. Activated carbon
injection technology can
reduce mercury emissions by
up to 90 percent when
combined with baghouses.
Other harmful pollutants emitted,
annually, from a typical,
uncontrolled coal plant include
approximately:
• 114 pounds of lead, 4 pounds
of cadmium, other toxic heavy
metals, and trace amounts of
uranium.
• Baghouses can reduce heavy
metal emissions by up to 90
percent.
• 720 tons of carbon monoxide,
which causes headaches and
places additional stress on
people with heart disease.
• 220 tons of hydrocarbons,
volatile organic compounds
(VOC), which form ozone.
• 225 pounds of arsenic, which
will cause cancer in one out of
100 people who drink water
containing 50 parts per billion.
Pollution control technologies are
commercially available and have a
long track record of effective
performance at many coal-fired
power plants.
4
FALL PROTECTION RESCUE PLAN
If any worker falls and is
suspended by a safety harness,
follow the Emergency Response
steps as below;
• The site supervisor (or
alternate) takes control of the
situation.
• The site supervisor raises the
emergency alarm. All workers
in the immediate vicinity of
the incident stop working. The
site supervisor quickly
evaluates the situation and
identifies any further hazards
that could arise.
• The site supervisor or his
designate goes to get help if
workers are close by. If no one
is close enough, the site
supervisor calls for help by the
possible ways.
• The site supervisor calls to
notify local police, fire, and
ambulance if required.
• The site supervisor (or a
worker assigned to the task)
isolates the accident zone and
its perimeter to limit further
exposure by suitable method.
• The site supervisor (or a
worker assigned to the task)
moves all non-affected
personnel to a safe zone or
directs them to remain where
they are.
• The site supervisor sends a
designated worker to the site
gate to meet the response
team (police, medical, fire,
etc.) and ensure that they
have a safe access path to the
incident scene.
• The site supervisor assembles
the emergency rescue team at
the incident site as quickly as
possible to determine the best
rescue procedure for the
situation.
Rescue Procedures
The following rescue procedures
are ordered (A) through (C), with
(A) being the preferred
A. Elevating Work Platform
Rescue: If an elevating work
platform (EWP) is available
on site and the suspended
worker can be reached by the
platform, follow the procedure
below.
1. Bring the EWP to the
accident site and use it to
reach the suspended worker.
2. Ensure that rescue workers are
wearing full-body harnesses
attached to appropriate
anchors in the EWP.
3. Ensure that the EWP has the
load capacity for both the
rescuer(s) and the fallen
worker. If the fallen worker is
not conscious, two rescuers
will probably be needed to
safely handle the weight of the
fallen worker.
4. Position the EWP platform
below the worker and
disconnect the worker's
lanyard, when it is safe to do
so. When the worker is safely
on the EWP, reattach the
lanyard to an appropriate
anchor point on the EWP, if
possible.
5. Lower the worker to a safe
location and administer first
aid. Treat the worker for
suspension trauma and any
other injury.
6. Arrange transportation to
hospital if required.
B. Ladder Rescue: If an
elevating work platform is not
available, use ladders to rescue
the fallen worker with the
procedure outlined below.
1. If the fallen worker is
suspended from a lifeline,
move the worker (if possible)
to an area that rescuers can
access safely with a ladder.
2. Set up the appropriate
ladder(s) to reach the fallen
worker.
3. Rig separate lifelines for
rescuers to use while carrying
(Contd. on next page)
5
out the rescue from the
ladder(s).
4. If the fallen worker is not
conscious or cannot reliably
help with the rescue, at least
two rescuers may be needed.
5. If the fallen worker is
suspended directly from a
lanyard or a lifeline, securely
attach a separate lowering line
to the harness.
6. Other rescuers on the ground
(or closest work surface)
should lower the fallen worker
while the rescuer on the
ladder guides the fallen worker
to the ground (or work
surface).
7. Once the fallen worker has
been brought to a safe
location, administer first aid
and treat the person for
suspension trauma and any
other injury.
8. Arrange transportation to
hospital if required.
C. Rescue from Work Area or
Floor Below: If the fallen
worker is suspended near a
work area and can be safely
reached from the floor below
or the area from which they
fell, use the following
procedure.
1. Ensure that rescuers are
protected against falling.
2. If possible, securely attach a
second line to the fallen
worker's harness to help
rescuers pull the fallen worker
to a safe area. You will need at
least two strong workers to
pull someone up to the level
from which they fell.
3. Take up any slack in the
retrieving line to avoid
slippage.
4. Once the worker has been
brought to a safe location,
administer first aid and treat
the person for suspension
trauma and any other injury.
5. Arrange transportation to
hospital if required.
Post-Rescue Procedure
All non-affected workers should
remain in the designated safe
gathering zone until the site
supervisor notifies them to do
otherwise.
The site supervisor and health
and safety representative should
• Begin the accident
investigation.
• Quarantine all fall-arrest
equipment that may have
been subjected to fall fatigue
effects and/or shock loading
for further investigation.
• Secure the area (an accident
scene not be disturbed where
a fatal or critical injury has
occurred).
• Determine whether or not the
jobsite-specific rescue and
evacuation plans were
followed as designed.
• Record modifications or
additions to the plans that the
rescue team deem necessary.
• Record all documented
communications with fire,
police, and other contractors
involved.
• Record all documented
statements from employees,
witnesses, and others.
• Save all photographs of the
incident.
• Record all key information
such as dates, time, weather,
general site conditions, and
specific accident locales
including sketches of the
immediate incident area,
complete with measurements
if applicable.
Fall Protection ....(Contd. from previous page)
DISCLAIMER: All information contained in this Journal, were obtained from sources, believed to be reliable and are collated, based on
technical knowledge and experience, currently available with the Editorial Board of SEA (India). While SEA (India) recommends reference
to or use of the contents by its members and subscribers, such reference to or use of contents by its members or subscribers or third
parties, are purely voluntary and not binding. Therefore the Editorial Board of this Journal or SEA (India) assumes no liability or responsibility
whatsoever towards any bad or undesired consequences.
6
HANDLING ELECTRICITY
Use of Earth Leakage Circuit
Breaker, E L C B
ELCB will not work if Neutral
input of ELCB is not not
connected to ground.
ELCB is used to detect earth
leakage fault. Once the phase and
neutral are connected in an
ELCB, the current will flow
through phase and the same
current will have to return to
neutral so resultant current is
zero.
Once there is a ground fault in
the load side, current from phase
will directly pass through earth
and it will not return through
neutral through ELCB. That
means once side current is going
through the phase and not
returning , hence because of this
difference in current ELCB will
trip and it will safe guard the
other circuits from faulty loads. If
the neutral is not grounded, fault
current will definitely be high and
that full fault current will come
back through ELCB, and there
will be no difference in current.,
ELCB will not function.
Difference between MCB &
MCCB
MCB is Miniature Circuit Breaker
which is thermal operated and
used for short circuit protection in
small current rating circuit.
Normally it is used where normal
current is less than 100A.
MCCB is Moulded Case Circuit
Breaker and is thermal operated
for over load current and
magnetic operation for instant trip
in short circuit condition. Under
voltage and under frequency may
be inbuilt.
Normally it is used where normal
current is more than 100A.
Earth Pin is always thicker and
Longer
In three pin plug the earth pin is
thicker and longer than the other
pins
It depends upon R=?L/A where
area (A) is inversely proportional
to resistance (R), so if area (A)
increases, R decreases & if R is
less the leakage current will take
low resistance path so the earth
pin should be thicker. It is longer
because it should make the
contact First and get disconnected
only at Last, after the phase
contacts.
This assures Safety for the person
who uses the electrical
instrument.
For lighting Loads, Delta Star
Transformers are used
For lighting loads, neutral
conductor is a must and hence
the secondary must be in star
winding and also the lighting load
is always unbalanced in all three
phases.
To minimize the current
unbalance in the primary, we use
delta winding in the primary
Hence delta / star transformer is
used for lighting loads.
Advantages of using Star/Delta
starter with Induction Motors
The main advantage of using the
star delta starter is to reduce the
current during the starting of the
motor. Starting current is reduced
to 3-4 times during starting and
also the voltage drops are further
reduced during starting.
Regenerative Braking
When the supply is cut off for a
running motor, it still continue to
run due to inertia. In order to
stop it quickly we place a load
(resistor) across the armature
winding. The motor will maintain
continuous field supply so that
back e.m.f voltage is made to
apply across the resistor and due
to load the motor stops quickly.
This type of breaking is
"Regenerative Braking".
When voltage increases then
current also increases. Then why
we need over voltage relay and
over current relay? Can we
measure over voltage and over
current by measuring current
only?
We cannot sense the over voltage
by just measuring the current only
because the current increases not
only for over voltages but also for
under voltage (As most of the
(Contd. on next page)
7
loads are non-linear in nature).So,
the over voltage protection &
over current protection are
completely different.
Over voltage relay is meant for
sensing over voltages & protect
the system from insulation break
down and fire. Over current relay
is meant for sensing any internal
short circuit, over load condition,
earth fault, thereby reducing the
system failure & risk of fire.
Hence, for better protection of
the system we should have both
over voltage & over current relay.
If one lamp connects between
two phases it will glow or not?
If the voltage between the two
phases is equal to the lamp
voltage then the lamp will glow.
When the voltage difference is big
it will damage the lamp and when
the difference is smaller the lamp
will glow depending on the type of
lamp.
What are HRC fuses and where
it is used?
HRC stand for “high rupturing
capacity” fuse and it is used in
distribution system for electrical
transformers
Different methods of starting an
induction motor
• DOL: direct online starter
• Star delta starter
• Auto transformer starter
• Resistance starter
• Series reactor starter
What is meant by knee point
voltage?
Knee point voltage is calculated
for electrical Current Trans-
formers and is very important
factor to choose a CT.
It is the voltage at which a CT
gets saturated.
What is reverse power relay?
Reverse Power flow relay are used
in generating stations' protection.
A generating station is supposed
to feed power to the grid and in
case generating units are off, there
is no generation in the plant then
plant may take power from grid.
To stop the flow of power from
grid to generator we use reverse
power relay).
What is the main difference
between UPS & inverter?
Uninterrupted power supply is
mainly used for short time. UPS is
also two types: on line and offline.
Online UPS having high volt and
amp for long time backup with
high DC voltage. Put UPS start
with 12v DC with 7 amps. Put
inverter starts with 12v, 24 DC to
36v DC and 120amp to 180amp
battery with long time backup.
Handling Electricity ....(Contd. from previous page)
HOW FIREWALL BARRIERS PREVENT ACETYLENE TANK FIRES
It is always safer to have a welding
cart with built-in firewall barrier.
Acetylene gas, the most common
gas used for fueling the cutting
torches, burns quickly and is very
easy to ignite. Even energy from a
static spark can be enough to
ignite it. And if the cylinder was
to catch on fire while next to the
oxygen cylinder it is important to
prevent the oxygen cylinder from
being heated to the point the
pressure relief valve in the
cylinder activates.
The OSHA regulation states that
oxygen cylinders in storage shall
be separated from fuel-gas
cylinders or combustible materials
(especially oil or grease), a
minimum distance of 20 feet (6.1
m) or by a noncombustible barrier
at least 5 feet (1.5 m) high having
a fire-resistance rating of at least
one-half hour.
Special attention needs to be
taken when storing or working
with acetylene or any fuel
gases.
The pressure-relief valve is
designed to release built up
pressure to prevent rupture of the
cylinder. If a cylinder is exposed to
intense heat, the contents will
expand causing the gas to be
released from the pressure-relief
valve. The released gas can then
mix with the burning fuel and
result in a more intense flame or
even explosion. Using a firewall
helps to and shield the flames and
escaping gases away from the
other cylinder and minimize heat
transfer.
8
MOST HAZARDOUS WASTES
CRT: (Cathode Ray Tube)
Monitors: CRT monitors, the
Display Screen used in old
computers. They contain on an
average, four pounds of lead each
in the elder version of TV screen.
Excessive lead and other toxins
pose a problem in landfills because
they can reach into groundwater
or, in the case of a lined landfill,
force expensive leachate
treatment. In combustors, the
lead winds up on the ash residue,
which in turn disposed of in
landfills. Lead exposure ahs been
linked with learning disabilities,
behavioral problems and at very
high levels, seizures, coma and
even death.
Batteries :
Lead-Acid / Automotive
Batteries: Lead batteries are this
country's principal source of
power for automobiles, trucks,
motorcycles, boats, forklifts, golf
cars, lawn and garden tractors,
and wheelchairs. These heavy,
rectangular batteries contain
sulfuric acid, which can burn skin
on contact.
Alkaline Batteries: Alkaline
batteries are standard household
batteries. They are used in
product from walkmans and
clocks, to smoke detectors and
remote controls. Since -1994,
most types contain no added
mercury or only contain trace
amounts. These batteries are
marketed "no added mercury" or
with a green tree logo.
Button Batteries: These batteries
are named for being small round
and silver-colored. They are most
commonly found in watches and
hearing aids. Many button
batteries contain mercury of silver
oxide, that are toxic to humans
when inhaled or ingested.
Nickel-Cadmium Rechargeable
Batteries: These batteries are
marked "Rechargeable" and are
found in many products including:
cell phones, cordless phones,
laptops, power tools, camcorders
and remote controlled toys.
NiCads contain cadmium, a metal
that is toxic to humans when
inhaled or ingested.
Lithium Batteries: These
batteries are mainly used in
computer, camcorders, laptop and
cameras, lithium ignites when in
contact with water and has been
notorious for causing serious fires.
Printers: Most printer cartridges
are easily recycled, refilled or re-
built. But printer vendors sell the
printer cheap, and make their real
money selling supplies. The "right"
environmental solution is to sell
new cartridges with a postage paid
mailer for returning the old one.
Some advanced companies, have
been known to do this especially
for laser printers.
Old Refrigerators, Heat Pumps
and Air Conditioners: Mostly,
old refrigeration equipment
contains Freon, a chemical known
as a Chlorinated Fluorocarbon or
"CFC". Each molecule of a CFC
can destroy over 100,000
molecules of the earth's protective
ozone coating, leading to
increased risk of sunburn,
cataracts and skin cancer for the
entire population of the planet
(human and animal)
Motor Oil: Used motor oil
contains heavy metals and other
toxic substances and is considered
hazardous waste. One quart of oil
can kill fish in thousands of
gallous of water. Motor oil
containers should mention the
danger of used oil to humans and
the environment.
Paper: Most types of paper can be
recycled. Newspapers have been
recycled profitably for decades and
recycling of other papers is rising.
Virgin paper pulp prices have
soared in recent years prompting
construction of more plants
capable of using waste paper. The
key to recycling is collecting large
quantities of clean, well-sorted,
uncontaminated and dry paper.
Glass, Steel Aluminum Cans
and Foil: Glass, steel and
aluminum are easy to recognize
and recycle. Glass bottles must
not be mixed with other types of
glass such as windows, light bulbs,
mirrors, glass tableware, Pyrex or
auto glass. Ceramics contaminate
glass and are difficult to sort out.
Clear glass is the most valuable.
Plastic: With a little bit of care,
plastic can be recycled. The
awareness of recycling plastic is
increasing rapidly. However, there
is one drawback. Different types
of plastics must not be mixed
together while recycling. This can
ruin the entire process of recycle.
9
HEALTH RISK ASSESSMENT (HRA)
Chemical and oil industry has
many diverse activities, including
processes, operations and
materials which can, in some
cases, pose risks to health, safety
and the environment. While
many tools are available and
widely used to identify and
evaluate safety risks, awareness on
Health Risks and identification
and control measures for the same
still remain to be ascertained.
What are the Health Risks?
Any hazard has, by definition, the
potential to cause harm in some
way. With simple hazards, we can
usually link the hazard (cause) to
the harm (effect) quite clearly.
For example, it is obvious that a
person struck by a brick falling
from an overhead scaffold, be-
cause the toe boards were missing,
was injured by the falling brick.
In contrast, health hazards are not
always obvious and the potential
harmful health effect may not be
as easy to link back to the cause.
As a result, measures for
controlling exposure to the hazard
may be inadequate or overlooked.
This is an important difference
between the assessment of safety
and health risks. Health risks
have a number of unique features
which need to be taken into
account when carrying out HRA.
This write up will provide some
background on what should be
considered when assessing health
risks and why it requires a
particular methodology to be
followed.
Key definitions
Health hazard: The actual agent
that causes harm to health.
Health hazards may be biological,
chemical, physical, ergonomic or
psychological in nature.
Health risk: The likelihood that a
particular health hazard as above
will cause harm in the actual
circumstance of exposure.
Exposure: The amount of the
hazard to which a person is
subjected (dose). This is a
combination of magnitude,
frequency and duration.
Occupational Exposure Limit:
The average level of exposure
intensity over a specified time
period set by an authority as the
recommended maximum.
Health risk is directly proportional
to the severity of a health hazard
and the level of exposure to that
hazard
Health Risk = Health Hazard x
Exposure
In most cases the human body
can cope with some exposure to a
health hazard. Indeed, there are
many examples where some
exposure is essential for good
health, for example, a certain level
of psychological stress or
chemicals that act as nutrients. A
key element in carrying out
Health Risk Assessment is to
determine when exposure to a
particular health hazard is too
great and could lead to ill health.
There are a number of features
particular to the health of
individuals which complicate this
simple relationship between
hazard and risk.
Acute and Chronic Health
Effects
Certain health hazards show their
effects at the time of exposure, for
example eye and throat irritants
or corrosives. These are called
acute effects and occur suddenly
and in a short time (seconds to
hours) following exposure. On
the whole, these are simpler to
work with because they are self-
indicating. It is obvious when
exposure occurs and, in most
cases, the individual can take
remedial action before damage is
done.
Chronic effects are more subtle.
These occur gradually over a long
period of time (often years)
following repeated or prolonged
exposure to a health hazard.
Because over-exposure is not
necessarily self-indicating, the
individual is not usually aware of
the exposure and its potential
results at the time, so does not
take remedial action.
Cumulative Exposures
When assessing health risks, it is
important to look at all exposures
to particular health hazards and
not to focus on each hazard and
exposure in isolation. With
health hazards, multiple exposures
can happen either simultaneously
or consecutively, adding to an
(Contd. on next page)
10
individual's total dose and
potentially increasing the risk. If,
for example, a combination of
chemicals with similar toxicity is
encountered, the effect will be the
sum of the effects of all the
chemicals, or even more.
Similarly, if several short tasks are
carried out, exposures from each
task may be carried forward to the
next.
People may be exposed to health
hazards in every aspect of their
lives, including home, hobbies and
leisure, as well as work. Where
the same hazard is involved, this
will add to the cumulative
exposure of an individual. For
example, people whose hobbies
expose them to chemicals, noise
or hand arm vibration are not
starting with zero exposure when
they begin work. This is
particularly important for
psychological hazards, where
domestic and relationship
pressures may affect an
individual's ability to handle their
work situation. While non-
occupational exposures are not
routinely included in the HRA,
such exposures may be relevant
when investigating an incident or
health effect.
Individual Susceptibility
Individual reaction to health risks
varies from person to person,
based on their heredity, age, sex,
personal habits, life history to
date, the state of their health at
the time and other unclear
factors. For example, a young, fit
person may be perfectly capable of
tolerating a certain level of
exposure, but an older or weaker
person may not. Previous health
damage like a back injury, hearing
loss or chemical sensitisation may
also put certain individuals at
particular risk. Pregnancy and
subsequent nursing of babies have
to be considered both for the
health of the mother and the
child.
Individual susceptibility is
particularly important when
considering psychological hazards
- what may be regarded by one
person as a stimulating challenge
may present an intolerable burden
to another.
Realistically, risk assessments have
to be fairly generic - it would be
impossible to assess how every
individual will react to every
health risk. So a standard
reasonably fit, reasonably stable
individual has to be generally
assumed. Where a health risk has
particular relevance to a group,
for example smokers or pregnant
women, and these are known to
be in the exposed population, a
further generic assessment for that
group may be necessary.
Health and medical surveillance
and medical fitness standards
should aim to protect individuals
with a particular susceptibility
which may represent an increased
risk to them.
Threshold Levels
Most health hazards have a
threshold level - the highest dose
at which no adverse effects are
seen, referred to as the No-
Observed Adverse Effect Level
(NOAEL). Health risks with
such a threshold, the severity of
the effect is proportional to the
exposure, down to the threshold
(which is above zero). Below that
threshold, there is no health effect
- the body's defence and excretion
mechanisms can cope with the
exposure burden. It is particularly
important to have the latest
Material Safety Data Sheet
(MSDS) for all the products
handled so that the most up to
date information is available.
Health Risk Assessment (HRA)
Identification and Control of
health risks at work offers Line
Managers and HSE engineers a
clear and practical guidance on
how to identify, evaluate and
control health risks at work - the
process is known as Health Risk
Assessment or HRA. It is
designed to be sufficiently flexible
to apply across company activities,
from a complex chemical plant to
a simple retail filling station.
The HRA Team should know far
more about the potentially
harmful effects of the agents
which can affect people's health,
including chemicals, dusts, noise,
heat, radiation and micro-
biological agents. The challenge
is to use HRA to apply this
knowledge to ensure that hazards
which could cause short term
(acute) or long term (chronic)
health effects are adequately
controlled.
Health Risk....(Contd. from previous page)
(Contd. on next page)
11
Health Risk Assessment:
Health Risk assessment is defined as
"The identification of health hazards
in the workplace and subsequent
assessment of risk to health". This
assessment takes into account
existing or proposed control
measures. Where appropriate, the
need for further measures to control
exposure is identified.
HRA is the process by which
health risks are addressed as part
of the company Health Safety and
Environment Management
System (HSE-MS). It should
cover and be applied to, all
employees, contractors and third
parties at work within company
premises.
It is the responsibility of
Operating Unit line management
to ensure that HRAs,
encompassing activities within the
scope of their HSE-MS, are
carried out and followed up in
conformance with the
methodology described in HRA
procedures. One or more
management representatives
should be appointed to steer the
implementation of HRA.
HRA must be carried out for:
• All new activities and
developments
• All existing operations
• Where there are changes to
existing activities
• For post-operating activities
• For acquisition (sufficient to
identify potential health
Health Risk....(Contd. from previous page)
liabilities - a full HRA is not
normally required)
The following steps should be
considered in carrying out any
HRA:
Organise
• Allocate adequate resources
and form a competent team
including specialist support
resources as required.
Break down activities into
Assessment Units based on the
scope of the HSE-MS.
Identify the hazards
• For each Assessment Unit
make an inventory of all
Health Hazards and their
potential harmful effects
(acute and chronic)
Assess the risks
• For each Health Hazard use
the HSE Risk Assessment
Matrix (RAM) to assess the
potential risk to the business
by plotting them on the
RAM to identify Low,
Medium and High risks
Control the risks
• For risks assessed as Low:
identify Occupational
Exposure Limits (OELs) and
other standards for the
Hazards concerned and
ensure that controls are
established and maintained
via standard procedures and
staff competencies specified
in the HSE-MS. Manage for
continuous improvement
• For risks assessed as Medium
and High: identify OELs for
each Hazard; identify the
required controls to limit
exposure to as low as
reasonably practicable
(ALARP) and to ensure that
OELs are met; compare the
required controls with
current controls and identify
any gaps; assess whether
current controls are being
effectively applied (it may be
necessary to test existing
controls or to carry out
exposure measurements to
determine their effective-
ness); identify and agree any
remedial actions and
measures necessary to ensure
that any identified gaps are
addressed and that controls
are consistently applied and
effective (measures to ensure
the continuing effectiveness
of controls may include:
routine exposure monitoring,
health surveillance,
maintenance of equipment
and staff education)
• For risks assessed as High,
give serious consideration to
alternative ways of carrying
out the operation to avoid
the risk
Establish Recovery Measures
Identify recovery (preparedness)
measures which would be
required to mitigate the potential
effects, should exposure control
measures fail.
• Compare required measures
with current measures; any
gaps should be identified and
(Contd. on next page)
12
remedial actions should be
determined.
• Carry out regular exercises to
test recovery measures and
checks on necessary
equipment.
Formulate and Monitor
Remedial Action Plans:
Incorporate all required remedial
actions into a Remedial Action
Plan (RAP), allocate the
necessary resources and put in
place a tracking system to monitor
implementation.
Documentation: Keep written
records of HRAs, RAPs and
consequent actions to act as
documented demonstration of
control of risk.
Review: A regular review of
HRAs must be carried out as part
of the formal review process of the
suitability and effectiveness of an
HSE-MS.
• Individual HRAs should be
reviewed, as a minimum,
every five years
• In addition, any significant
change, which may impact
on health risk, should trigger
a review of the HRA
• Processes must be included
within HSE Assurance Plans
to ensure the requirements
are being met.
• Outputs from HRA should
be managed via the HSE-MS
to ensure the ongoing control
of health risks and a
continuing improvement in
workplace health.
Health Risk Assessment applies
to:
• All operations within the
scope of the HSE-MS.
Health Risk....(Contd. from previous page)
Flow chart for a typical HRA
HRA addresses the life cycle of
any operation, and takes account
of all employees, contractors and
third parties at work.
• New Activities and
Developments
Implementation of HRA at the
conceptual and detailed design
stages of new activities and
developments allows selection of
control and recovery measures
when it is easiest and cheapest to
integrate them in any plan. In
this way, control is focused at the
top of the control hierarchy.
Using the plans and process
descriptions, together with
discussions with design engineers,
health specialists and operational
staff, the first step is to identify the
potential health hazards that may
be encountered and identify
Exposure Limits. It is also
necessary to predict the tasks
involving exposure to those
hazards and the likely levels. This
information should then be used
to select the control design
standards. In addition, it provides
a key input into operating
procedures.
Once the new activity/
development is up and running, it
is appropriate to test the
effectiveness of the controls by
implementing HRA for existing
operations. Of course, the design
HRA will provide a head start.
(To be Concluded in the next issue)
13
CASE STUDY 1:
SCALDED BY HOT LIQUID
FROM INCINERATOR:
Description of Incident
Solid waste cakes were fed into
the rotary kiln of an incinerator
through a supply nozzle. After
combustion, the ashes formed
would be channelled into a slab
box. When the control panel
indicated an abnormal drop in the
temperature within the kiln, two
workers decided to carry out a site
inspection. Fog and liquid deposits
were observed at the base of the
kiln. When they opened the slab
box for inspection, the two
workers came into contact with
the discharged hot liquid. One
worker succumbed to burn
injuries while the other ended up
being hospitalised for more than
four months.
Possible Causes and
Contributing Factors
Man
• The workers opened the door
of the slab box without
assessing the risks posed by the
abnormal drop in temperature
within the kiln.
Machine
• The supply nozzle could have
cracked due to thermal stress
causing the cooling water to
leak into the kiln. The
presence of cooling water in
the kiln led to a drop in the
temperature within the kiln.
Management
• The management failed to
identify the impact of thermal
stress on the supply nozzle
during process hazard analysis.
• A safe work procedure was not
available for slab box
inspection under abnormal
conditions.
• There was no maintenance
regime for the supply nozzle.
• The workers were not
provided with specialised PPE
for the task.
Recommendations and Learning
Points
• Review the process hazard
analysis to determine if there
are more or new hazards and
implement suitable risk
control measures to address
each identified risk.
• Conduct a proper root cause
analysis to determine the
actual cause of nozzle failure
(e.g., due to thermal stress,
inadequate material of
construction, poor nozzle/joint
design, etc.)
• Establish a regular inspection
and maintenance regime for
the supply nozzle.
• Allow the workers to stop the
incinerator operation in the
event of process abnormality.
• Develop safe work procedures
and train the workers for slab
box inspection under
abnormal conditions. In
general, equipment under
operation should not be
CASE STUDY
Causal Analysis
Evaluation of loss • One fatality and one worker seriously injured
Type of contact • Contact with hot substance
Immediate cause(s) • A crack in the nozzle which caused the cooling water
to leak into the kiln
Basic cause(s) • Inadequate process hazard analysis.
Failure of OSHMS • Hazard identification, risk assessment and risk control.
• Operating procedures and safe work practices
• Mechanical integrity and reliability (of the supply nozzle)
opened for inspection without
establishing the cause of the
abnormal condition. To
minimise the risk to workers,
all hazards must be identified
and control measures put in
place before inspecting the
equipment.
• Equip the workers with
suitable fire retardant PPE
when working with hot
substances.
(Contd. on next page)
14
Case Study....(Contd. from previous page)
CASE STUDY 2:
FALL FROM HEIGHT WHILE
CLIMBING ROPE LADDER:
Description of Incident
After helping to dismantle a metal
scaffold inside a reactor, a worker
was at the base of the reactor
getting ready to exit through the
overhead reactor manhole. While
the worker was on the way up the
vertical rope ladder, he fell and
landed at the base of the reactor.
The worker was immediately
rescued but he died on the way to
the hospital.
Possible Causes and
Contributing Factors
Mission
• Upon dismantling the scaffold
inside the reactor, the workers
were required to climb up 14
m to exit via the overhead
reactor manhole.
Man
• The worker did not attach his
body harness to the provided
fall arrestor and retractable life
line.
• The worker lost his grip when
climbing up the rope ladder.
Management
• There was a lack of
supervision to ensure that
each worker attached their
body harness to the provided
life line before climbing up the
rope ladder.
Recommendations and Learning
Points
• Prior to working in a confined
space (i.e., the reactor in this
case), the entry permit must
be obtained and the necessary
gas checks are carried out by
a Confined Space Safety
Assessor. The confined space
must be adequately ventilated
and lit for the task to be
carried out.
• Ensure that the workers are
wellrested and medically fit for
strenuous work activities such
as using the rope ladder for
access to and egress from the
designated work area.
• Implement a Fall Prevention
Plan to address all risks
associated with working at
height.
• Emphasise the need to
properly secure the body
harness before using the rope
ladder during worker training
Causal Analysis
Evaluation of loss • One fatality
Type of contact • Falling from height
Immediate cause(s) • Did not attach body harness to life line
Basic cause(s) • Not following safe work procedure
Failure of OSHMS • Operating procedures and safe work practicesand/or toolbox meetings, and
highlight its importance in the
safe work procedures.
• Introduce a buddy system to
verify that each worker has
attached his body harness to
the life line before climbing
the rope ladder.
• For safer means of access and
egress, explore the use of a
fixed ladder instead of a rope
ladder.
15
IN THE NEWS
W H O New Director General Dr Tedros Adhanom Ghebreyesusfirst address
WHOs work is about serving people, about serving humanity.
Its about serving people regardless of where they live, be it in developing or developed
countries, small islands or big nations, urban or rural settings.
Its about serving people regardless of who they are poor or rich; displaced or disabled, elderly
or the youth.
“Most importantly its about fighting to ensure the health of people as a basic human right”.
FIVE top Priorities of WHO
1 Ensure universal health coverage for all people without impoverishment
2 Respond quickly & effectively to public health emergencies
3 Secure the health, dignity & rights of women, children and adolescents.
4 Decrease the health impacts of climate & environmental changes
5 Transform W H O with a more effective, transparent and accountable Agency.
XXI World Congress on Safety and Health at Work:
A Global Forum for Prevention
The ILO, the Ministry of Manpower of Singapore (MoM) and the International Social Security
Association (ISSA) jointly organised the XXI World Congress on Safety and Health 2017 at
Singapore on September 3-6, 2017.
Objectives of the World Congress
• To provide a forum for the exchange of knowledge, practices and experience between
participants with the aim of promoting safety and health at work.
• To reinforce and build networks and alliances while laying the groundwork for cooperation
and strengthening relationships among all concerned.
• To provide a platform for the development of knowledge and strategic and practical ideas
that can be immediately put into use.
The World Congress is the OSH event of the year. Participants keep up to date on OSH issues,
meet experts from all over the world, and network, locally and interactively. The programme
reflects the most important OSH topics worldwide. It offers world-class speakers, interactive
attractions, and a wide range of topics. In addition, the 2017 Congress included a parallel
SafeYouth@Work Congress bringing together OSH experts and Youth Champions for Safety
and Health at work.
16
