24 June 2013
From: Senior Safety Manager
To:
General Manager
Subj: ACTIVITY HAZARD RISK ASSESSMENT #25-2013, FOR PNH PROJECT TO CONSTRUCT RESTROOM FACILITIES FOR MSC SSU IN
BLDG. 6-4, EXCAVATION WORKS, AND IS AN ADDENDUM TO AHA #29 FROM 2012 FOR THE CONSTRUCTION OF THESE SPACES
Ref: (a) USACE EM 385-1-1
(b) Ministry of Manpower Regulations Regarding General Safety and Health
1. Per reference (a), this risk assessment was completed to identify hazards that pose risk to workers, evaluate those hazards for
severity and likelihood of occurrence, and recommend corrective actions that will eliminate or minimize hazards associated with the
extent of excavation that is required for the completion of this project. On the original plan this level of excavation was not
anticipated, however, after getting into the scope of the required work it was determined that a trench is required to run
approximately 50 meter along the south end of Building 6-4 to install the drain lines required to support this new restroom facility.
This AHA will be reviewed periodically and updated as needed to reflect changes in working conditions, processes or addition of new
materials or equipment.
Please address any questions or concerns to me at 8205 8249 or lee_wilson@pnhgrp.com.
Respectfully,
T. L. Wilson
Risk Assessment Form
#25-2013, Activity-Based Risk Assessment for Excavation Work at Bldg. 6-4, MSC SSU RESTROOMS
Inventory of Work Activities
Company: PNH Resources LTD PTE
No.
1
Process Description
Site Preparation
2
Trench Construction
Work Activities
Prepare the site for excavation work. The proposed trench will run
between the south side of Bldg. 6-4 and the Australian Work Shop.
Back Hoe and Manual Labor to be used to dig the trench
3
Install piping in trench
Laying Pipe between the proposed restroom and
4
Fill in the trench
Fill the trench with dirt obtained from digging the trench.
5
Heat Stress
This work is being conducted outdoors and will present heat exposure
challenges to workers.
ACTIVITY RISK ASSESSMENT – MATRIX EMPLOYED TO QUANTIFY RISK
Risk Criteria
Severity (1-5, Lowest – Highest)
Likelihood ( 1-5, Lowest - Highest)
24 June 2013
1-Negligible Injuries: slight injury or health effect,
2-Minor Injuries: Injury or ill health requiring first aid treatment only
3-Moderate Injury: Injury requiring medical treatment or ill health leading to disability
4-Major Injury Disability: serious injury or life threatening occupational disease
5-Castrophic: serious injury resulting in fatality or irreversible health damage with death
1-Rare: very unlikely to happen,
2-Remote: not likely to happen most of the time,
3-Occasional: likely to happen sometime,
4-Major Injury Disability: likely to happen several times regularly,
5-Almost Certain: Likely to happen
Risk Level (Severity x Likelihood)
Trivial Risk
:
Tolerable Risk :
Moderate Risk :
Substantial Risk :
Intolerable Risk :
1 to 2 (L)
3 to 9 (L)
10 to 19 (M)
20 to 24 (H)
25 (H)
- First aid treatment injury, minor cuts or bruises, clean-up effort for environmental impact
- First aid treatment Injury, minor cuts or bruises, clean-up effort for environmental impact
- Temporary disability, lost time injury, outpatient treatment, minor or short term environmental impact
- Serious Injury, permanent disability, major disruption and damage to equipment or structure, significant environmental
- Fatality or fatalities, serious injury, permanent disability, major structural or equipment damage, detriment environmental
The table above provides numerical methodology to better prioritize hazards. These values are the
criteria for the Activity-Based Risk Assessments beginning on the following page. No catastrophic
risk of any certainty was identified.
Risk Assessment Form
Activity-Based Risk Assessment Form
Company:
PNH RESOURCES PTE LTD
Process/Location:
Tree Trimming/Pruning/Removal at the
Sembawang Complex, Sembawang, Sg.
Approved by:
Joseph Lim
(Name, designation)
General Manager
(Date)
24 June 2013
1. Hazard Identification
Conducted by: (Names,
designations) (Date)
Ministry of Manpower
Regulations
Ref: EM385-1-1, Chp. 31
Last Review
24 June 2013
Date:
1b
1c
1d
2a
2b
No
Work
Activity
Hazard
Possible
Accident/
Ill Health &
Persons at
Risk
Existing Risk
Control
(if any)
Severity
Site Preparation
– the area
where the
trench is to be
constructed is
not a significant
traffic area but
there is access
to the general
public and they
must be
protected from
falling into the
trench when it
is open
Cave in trapping
workers – The
anticipated depth
of the trench to
be no greater
than 1.3 meters
and at this depth,
a protective
system is not
required,
Workers down in
the trench which
could also be
affected by
weather
conditions i.e.
rain could make
trench sides more
unstable.
Falling into the
trench –
Workers on this
project in addition
to others who
2
Next Review
Date:
2. Risk Evaluation
1a
1
Lee Wilson
Senior Safety Manager
24 June 2013
The project
manager shall
observe the
condition of the
trench sides.
01 December 2013
3. Risk Control
2c
2d
3a
3b
Liklihood
Risk
Level
Additional Risk Control
Action
Officer
Designation
2
2
4
Shoring materials are available on site to
be deployed as needed.
Senior Safety
Manager
3
2
6
Signage should be posted to alert all in
the vicinity of the worksite of the
potential hazards.
Senior Safety
Manager
The soil was noted
to be of a sandy
clay type of
material.
wander into the
worksite.
No
2
3
Work
Activity
Hazard
Digging of the
Trench – A subcontractor will
be employed to
mechanically
dig the trench
with the
assistance of
mechanical
diggers.
Lacerations,
Bruising and
Crushing type of
injuries from
accidental or
incidental contact
with the back hoe
machine.
Workers
performing
manual labor
adjacent to the
backhoe when it
is being used.
Musculoskeletal
Installing pipe in
the trench
Possible
Accident/
Ill Health &
Persons at
Risk
Existing Risk
Control
(if any)
Severity
Likely- Risk
hood
Level
Project supervisor
shall ensure that
workers maintain
a safe distance (a
minimum of 10
meter) away from
the backhoe when
it is in operation.
3
2
Personnel
engaging in
manual digging
operations may
be subject to
strains and
sprains to
ligaments and
muscle structures.
Workers have
received training
with regards to
preventing these
types of injuries
and also the value
to teamwork in the
completion of this
type of work.
2
2
4
Sight Hazard
from flying
debris
Workers
involved with
the excavation
of the trench
Workers have
been issue sight
protection and
have received
training on the
need to wear
this equipment
on the job at all
times.
2
2
4
PNH workers receive Sight
Conservation training several times a
year and more often as the work may
dictate.
Senior Safety
Manager
Musculoskeletal
Workers actively
involved with the
pipe installation
Training, utilizing
teamwork as
needed.
2
2
4
The risk level is considered to be low as
the workers performing this labor are
young, in good health and have been
screened for exiting musculoskeletal type
Senior Safety
Manager
6
Additional Risk Control
Report any and all near misses or any
situations where a lessons learned
situation may exist.
Workers need to be wearing all of their
issued PPE on the job including:
Safety Shoes
Hard Hats
Eye Protection &
Hearing Protection when working around
the backhoe.
The risk level is considered to be low as
the workers performing this labor are
young, in good health and have been
screened for exiting musculoskeletal type
of injuries.
Action
Officer
Designation
Senior Safety
Manager
Senior Safety
Manager
of injuries.
No
4
5
Work
Activity
Hazard
Possible
Accident/
Ill Health &
Persons at
Risk
Existing Risk
Control
(if any)
Fill in the trench
Fall hazard – the
dirt on the sides
of the trench is
loose and could
facilitate workers
stumbling and
falling into the
trench and being
injured.
Workers involved
with filling in the
trench after the
pipe has been laid
Lacerations due
to shovel work
Heat Cramps
Heat Rash
Heat Syncope
Heat Exhaustion*
Heat Stroke**
Heat Stress
*If not treated
properly can
progress to heat
stroke.
**Life
Threatening and is
a real medical
emergency.
Definitive medical
assistance must
be summoned.
Severity
Likely- Risk
hood
Level
Additional Risk Control
Action
Officer
Designation
Attention to the
work environment
and ensuring that
hasty work does
not facilitate
increased risk.
2
3
6
Report all injuries sustained to the project
manager and Safety Department.
Senior Safety
Manager
Workers
working with
shovels and
other workers
who may be in
the area.
Attention to the
work
environment and
knowing the
proximity to
other workers.
2
3
6
Ensure that it is understood that too
many workers in a small area can
facilitate accidents and injuries.
Senior Safety
Manager
Personnel
performing work
outdoor in
Singapore
Tool Box Talk
Training
concerning heat
stress, clean
drinking water at
all job sites,
sufficient rest
periods for
workers in
accordance with
NAVMED P-5010
and Ministry of
Manpower
Recommendations
3
2
6
Continue emphasis on heat injuries
whenever safety stand downs, events,
tool box talks etc.. are planned. Ensure
that drinking water is always available for
crews working in heat stress conditions.
Ensure that sub contractors receive
training on the Heat Stress Program
observed at the Sembawang Compound
including the use of colored flags. A flag
system is employed at the Fleet Gym
which is adjacent to this project.
Supervisors shall also ensure that workers
have ample opportunity to drink water as
needed and take breaks during periods of
extreme heat especially if the heat index
hits 34C or above.
Senior Safety
Manager
Heat Stress
(Color)
Green
Yellow
Red
Black
Calculations:
Condition
I
II
III
IV
Heat Stress WBGT
Temperature
Activity Level
27.78-29.39 C (82-84.9F)
Discretion is required when planning heavy exercise for acclimatized personnel.
29.44-31.06 C (85-87.9F)
Strenuous exercise and activity for new and un-acclimatized personnel during the first 30 days of heat exposure.
31.11-32.17 C (88-89.9F)
Strenuous exercise should be curtailed for personnel with less than 12 weeks of training in hot weather.
Above 32.22 C or (Above
Physical training and exercise should be curtailed for all personnel (operational commitments excluded).
90F)
Heat stroke likelihood is high under conditions of high exertion.
WBGT = WB X 0.7 + DB X 0.1 + GT X 0.2
Meter calibration should be manually verified every 3 months. Manual calculation must be 0.2 + the meter WBGT readout