what is the Safety?
Safety is free from risk and danger (The word safety drives from the Latin word SALVUS means uninjured and healthy)
Q. What are the responsibilities of a Safety Officer?
The HSE Officer acts an advisory capacity to the management and supervision with regards Health and Safety Environment,
He is to monitor and ensure that the activities are being performed with the acceptable safety norms.
Helping supervisors to identify the hazardous and unsafe conditions and ensuring rectifications.
Conducting tool box meeting, Supervisors safety meeting, conducting training in various topics, conducting safety incentive program, conducting safety
Taking disciplinary action against the violations. Conducting risk assessment and JSA, pre task meeting and all other project
related safety requirements.
Keep track record all incidents at site.
He is to investigate hazards and dangerous occurrences, examine the cause of accident, and carry out safety inspection on site and what remedial steps/action has been under taken.
Q. What is a ‘Permit to Work’ Procedure / Work Permit System?
The „Permit to Work‟ (PTW) Procedure is a formal written system, which utilize a document to control the work by means of potential hazards identification and risk
assessment. The work permit is also a means of communication among various supervisors or their respective belonging to operation, maintenance, controlling teams and contract personnel, who are involved in work preparation and / or its execution.
Q. Explain Types of Work Permit normally used in oil & gas industry?
Types of Work permits: 5 types of work permit
1. Hot Work Permit (red)
2. Cold Work Permit (green)
3. Radiography Permit (yellow)
4. Vehicle/mobile plant entry work permit
5. Confined Space Entry Permit
(a) Cold Work Permit:
A document that specifies precautions identifies hazards and controls all work that is
not hot and radiographic in nature.
(b) Hot Work Permit:
A document that specifies precautions, identifies hazards and controls all work
involving actual naked flames, sparks or has potential for creating sparks or heat.
(c) Radiography Work Permit:
A document that specifies precautions identifies hazards and control all work involving
radiographic in nature.
(d) Vehicle / Mobile Plant Entry Permit:
A document that specifies precautions identifies hazards and controls all work
involving entry of a vehicle or mobile plant into a hazardous area.
(e) Confined Space Entry Permit:
A document that specifies precautions identifies hazards and controls all work
involving entry to an enclosure, which has limited means of entry or exit, not designed
for continuous occupancy.
Q. What is Cold work, Hot Work and Radiography work?
Any work that does not involve a source of ignition or naked flame or does not have
spark generating potential is classified as a Cold Work.
Any work which involves the use of naked or a source of ignition or spark generating
potential is classified as a Hot Work.
Any work that involves the use of a radioactive source, shall be covered by a
Q. What is the Excavation? And types of excavation?
Any man made cavity, cut, trench or depression on an earth surface formed by earth
Types of Excavation:
A. Manual Excavation: The excavation without using any powered equipment.
B. Mechanical Excavation: The excavation work using any electrical or mechanical
Q. What is EXCAVATION HAZARDS?
* Cave in or collapse of soil
* Risk due to presence of underground installations, pipelines, cables.
* Drowning due to water seepage into trench.
* Soil vibration due to machinery / heavy vehicles operations in the vicinity.
* Lack of Oxygen or asphyxiation etc.
* Underground obstruction or damage to buried pipelines & services
* Accidental fall of personnel or equipment inside a trench
* Struck / hit by excavating machinery
* Dropped / falling objects
* Flammable & / or toxic gas release
* Exposed to airborne contaminants
* Fire & explosion
* Electrical shock due to contact with energized electrical / telecom cable.
* Possible presence of explosive devices
* Damage to shallow underground services due to weight of heavy equipment such
as mechanical excavator.
* Encountering wet soil (mixed with water) or reaching water table.
* Encountering contaminated soil
Q. What is confined space?
* Any enclosure having a limited means of entry & exit and it is not designed for
* There will be a presence of any hazardous substances such as flammable and
toxic gases, oxygen deficiency, hot or humid atmosphere or any combination of it.
Examples: Process vessels, Tanks, Bins, Stacks, Large pipe, Duct, Pits & Trench etc.
Any excavation with depth more than 1.2 meter.
Q. What are the Confined Space Hazards?
A confined space may have one or combination of the following hazards:
* Oxygen deficiency
* Presence of flammable, combustible or pyrophoric materials (HC, Sludge etc.)
* Presence of toxic gases, corrosive or hazardous materials (H2S, Co, NH3 etc.)
* Poor illumination, Ventilation & Communication.
* High temperature and humidity.
* Limited entry & exit / Restricted access.
* Restricted movement inside.
* Falling / Tripping hazards
* Presence of reactive or self-igniting material.
* Hazard due to electricity or moving machinery.
* Hazard due to pressurized fluid.
* Hazard due to nature of work carried out inside confined space.
Q. What is the procedure for entering a confined space hazards?
1. Permit must be procured form operations, making sure of the following.
a. Complete isolation of the space to be entered.
b. Draining, depressurization and purging or cleaning should be performed.
c. Gas test should be conducted to ensure no hazardous atmosphere is present.
d. Space ventilation.
2. A Pre task meeting must be conducted with all authorized entrants prior to entering
3. The attendant (Stand by man) shall be assigned at the entrance to maintain
communication with employees working inside to ensure their safety. A log book
shall be maintained at the entrance to keep track of the people inside the space.
4. Safety attendant must be trained and authorized to use gas testing equipment.
5. Entrants must wear body harness, and if necessary a life line be attached to the
harness to avoid entry-rescue.
6. Lighting should be provided, if necessary a maximum of 24 volts, lighting should be
used attached a GFCI.
7. Only intrinsically safe or explosion-proof equipment shall be used inside.
8. Depending on the situation, emergency rescue team may be put on standby.
9. If an emergency occurs within the confined space, the standby person must not
enter it until rescue team arrived.
10. Barricade the area with warning sign board.
Q. What you know about working in a confined space entry?
Any enclosure having a limited means of entry & exit and it is not designed for continuous
* Before entering in the confined space, must need to obtain a confined space
entry work permit, make sure that all required isolation being done.
* Frequently gas test is to be carried out to confirm that area is free of toxic gas or
* If the area is contaminated or it has oxygen deficiency the provided BA sets or airline respiratory system.
* Conduct pre-task meeting for the employees who will be entering inside the
confined area and get there signature to conform that they are aware of the
hazards and safety measures.
* The attendant (Stand by man) to assigned at the entrance. A log book shall be
maintained at the entrance to keep track of the people inside the space. The
attendant shall not be assigned to other duties. If an emergency occurs within the
confined space, the standby person must not enter it until rescue team arrived.
* The entering people should use body harness with lifeline for the emergency
* Any required electrical lighting or tools should not exceed more than 24 volts and
attached with GFCI / ELCB. It should be intrinsically safe or explosive proof.
* Barricade the area with warning sign board.
Page: 9 of 35 HSE Questionnaire for Interview
Q. Explain H2S? OR What is H2S and its characteristics explain?
• H2S is produced or generated by decomposition of organic materials.
• It is a highly toxic gas and highly flammable.
• Its smell like rotten egg at low concentrations and not detectable by order at high
• It is highly flammable. (Flammable at 4.3% to 45.5% by volume in air)
• It is colorless.
• It is heavier than Air. (1.19)
• It is highly soluble in water and other liquid.
• When burned or flared it forms Sulphur dioxide (SO2) which is also colorless and
highly toxic gas.
• The exposure limits 10 PPM is the maximum allowed for 8 hours.
• Increasing exposure will cause headache and irritation of eyes.
• 800 PPM or more will be instantly fatal.
TLV-TWA of H2S = 10 ppm
TLV-STEL of H2S = 15 ppm
IDLH of H2S = 100 ppm
Note: – Up to 10ppm work can be done without respiratory protection system.
– 10 to 100ppm work can be done by SCBA or Air lined breathing apparatus.
– Above 100ppm work not permitted, allowed only for rescue.
Q. What are prominent H2S HAZARDS?
* Eyes and respiratory irritation.
* Dizziness, headache, nausea, abdominal pain.
* Loss of consciousness, Brain damage possible, death / fatal.
Q. Explain the precautionary measures to be taken while approaching
Precautionary Measures – H2S:
* Sufficient number of escape masks shall be kept in areas where H2S is liable to
* In case H2S presence is suspected in an area, the persons must put on escape
mask immediately and toxic gas test must be made immediately with appropriate
detector to determine the concentration of H2S in air.
* Working person should be equipped with personal detectors and alarming device
to alert in case of H2S presence.
* In case of H2S alarm, all personnel should vacate the area after donning the escape
set / breathing apparatus and report to the designated assembly point for
* If working in H2S contaminated atmosphere must wear suitable BA set and work in
pairs to support and rescue each other in the event of difficulties.
* Know the wind direction and evacuate in the cross wind direction in case of H2S
* Never go to a low-lying area during H2S leak.
* Paste H2S warning sign in H2S prone areas.
* The presence or suspected of H2S in any part of the plant or sewer shall be
reported immediately to supervisor and respective area fire station for arranging
rescue and support.
Q. How to treatment of persons affected by H2S?
Positive pressure breathing apparatus must be worn by any persons attempting a
* The victim must be immediately moved to fresh air, possibly in the upwind direction
of the gas leak. The rescuer must be outside the contaminated area before
removing his/her personal BA set.
* If the victim has stopped breathing, resuscitation must be started immediately,
using artificial respiration or a resuscitator if available. Resuscitation must be
continued until the victim starts breathing unaided or until qualified medical
assistance arrives. Medical help must be summoned as soon as possible.
Q. Define TLV-TWA, STEL and IDLH?
Time Weighted Average (TWA) concentrate of the contaminant in air over the normal
work shift of 8 hours, to which workers can be exposed without respiratory protection
in a 40 hour workweek.
Short Term Exposure Limit (STEL) when exposed only for a short period of 15
minutes. This maximum concentration can be allowed to breathe 4 times during 8
hours with minimum 1-hour interval between exposures.
Minimum concentration of contaminant in air which is Immediately Dangerous to Life
and Health (Note: Air supplied respirators are required in IDLH atmospheres.)
Q. What is Flash Point (FP)?
Minimum temperature at which a flammable mixture of gas or vapor in air will
momentarily flash when a source of ignition (spark) is introduced.
Q. What is Auto Ignition Temperature (AIT)?
Minimum temperature required to initiate self-sustained combustion of a solid, liquid or
gas in the absence of a source of ignition.
Q. What are LEL/LFL and UEL/UFL?
Lower Explosive Limit (LEL): or (Lower Flammable Limit)
Minimum concentration of vapor or gas in air which will burn when a source of ignition
(spark) is introduced.
Upper Explosive Limit (UEL): or (Upper Flammable Limit)
Maximum vapor/gas to air concentration above which flame propagation will not occur,
i.e. the mixture is “too rich” to burn.
Note-1: Flammable Gas Detectors (Meters) measure % LEL, hence actual LEL means
100% of full-scale reading of the meter. Below LEL (100% of meter reading), a
mixture is “too lean” to burn.
Note-2: LEL of airborne combustible dust: If the dust obscures vision at a distance of 5
feet (1.52 m) or less it is considered as at LEL (ex. Sulfur or coke).
Q. What is scaffolding?
Scaffolding is a temporary working platform to provide supports both men and materials for
working place. It is used in maintenance, construction and demolition work etc.
Types of scaffoldings:-
* Permanent scaffolding
* Hanging scaffolding
* Suspended scaffolding
* Mobil scaffolding.
Q. What are the points to be checked while green tagging erected
Before using of scaffold check the tag (7 days validity).
Green tag we can use the scaffold and Red tag for not use and Yellow tag use only for
* Level and firmness of the ground.
* Sole plate
* Base plate
* Planks (boards)
* Guard rails
* mid rail
* Out riggers
Q. What is Potential Hazards of scaffolding?
* Collapse of Scaffolding.
* Falling from height.
* Falling object.
* Slip & Trip hazards.
* Pinch point hazards / Sharp edges
* Opening without guardrail.
* Scaffold erection during storm or high winds, raining and poor visibility.
* Blocking emergency access and walkways
Q. What is the cause of scaffolding failure?
* Slipping of unsecured ladder.
* Use of unsuitable scaffold or faulty materials.
* Inadequate or irregular platform width.
* Omission of guard rails or toe boards.
* Failure to proper secure the scaffold to the building or to brace it adequately.
* Overloading on the scaffold platforms.
Q. What is the precaution during scaffolding erection?
* Scaffolding erection, dismantling should be done under the supervision of a
COMPETENT PERSON (Scaffolding Supervisor).
* Red Tag means Danger “do not use” and Green Tag means “scaffold complete ready
for use” when completed.
* Gap between boards/planks should be 1 inch (25mm).
* Top guardrail, mid-rial and toe board should be provided.
* Guard rails and Toe boards shall be fitted to the inside of standards.
* Guard rail should have a height between 915 mm (0.9 m or 90 cm or 3‟ feet) to
1143 mm (1.15 m or 3‟ 9”)
* Toe board should be 6” (15 cm) high and secured with toe board clips.
* If scaffold to be erected on soft ground should be used sole plate.
* Worker shall be not work on scaffolds during storms or high winds or poor visibility.
* Sole plate shall extend under at least two standards.
* Base plates with screw jacks should be proper scaffold leveling adjustment.
* All standard shall be vertical.
* Ledgers shall be securely fixed to standards couplers.
* Scaffolds should be properly braced by cross bracing or diagonal braces or both
for securing vertical members together.
* Access ladder must be provided for any platform & clamped with scaffold structure.
* Ladder should be 4:1 ratio and angle 750
* Ladder should be rise 1 meter (42 inch) above from