NEBOSH
NEBOSH INTERNATIONAL TECHNICAL
CERTIFICATE IN OIL AND GAS
OPERATIONAL SAFETY
UNIT IOG1: MANAGEMENT OF INTERNATIONAL OIL AND
GAS OPERATIONAL SAFETY
WEDNESDAY 7 MARCH 2012
2 hours, 0930 to 1130
Answer both Section 1 and Section 2. Answer ALL questions.
The maximum marks for each question, or part of a question, are shown in brackets.
Start each answer on a new page.
Answers may be illustrated by sketches where appropriate.
This question paper must be returned to the invigilator after the examination.
SECTION 1
You are advised to spend about half an hour on this section, which contains ONE question.
1
(a)
Outline the contents of a typical permit-to-work.
(8)
(b)
Outline how the contents of a hot work permit are different to a typical
permit-to-work.
(4)
(c)
(d)
Give the meaning of the following terms:
(i)
Lower Flammable Limit (LFL);
(2)
(ii)
flammable range.
(2)
The flammability of gas is a factor to consider with maintenance tasks and
particularly hot work permits. The diagram below highlights the flammable
range of a gas.
Explain the significance of the atmospheric range between 0% and the
LFL, indicated as (a) on the diagram, in relation to hot work permits.
(4)
Flammable Range
100%
Upper
Flammable
Limit (UFL)
Too rich
Air
Air
Flammable
Atmosphere
Range
Lower
Flammable
Limit (LFL)
Fuel
(a)
0%
IOG1/S/1203 © NEBOSH 2012
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SECTION 2
You are advised to spend about one and a half hours on this section, which contains TEN questions.
2
A road tanker is being driven from an onshore refinery to a petroleum (gasoline)
station.
Identify control measures that could minimise risk to the driver.
(Unloading issues are NOT required in the answer).
3
4
(8)
A distillation column requires protection from fire exposure through active or
passive fire protection.
(a)
Outline how a fixed water deluge system could provide fire protection.
(2)
(b)
Identify TWO additional examples of active fire protection.
(2)
(c)
Identify TWO examples of passive fire protection.
(2)
(d)
Outline why the metal legs of the column should be protected.
(2)
(a)
Identify TWO elements of the fire triangle.
(2)
(b)
Outline the significance of the three elements of the fire triangle.
(1)
(c)
An oil pipeline with a normally open isolating valve is on fire. A bypass line
with a normally closed isolating valve exists upstream of the fire.
Bypass Line
Normally Closed
Isolating Valve
Fire
Limited Oil
Supply
Normally Open
Isolating Valve
With reference to the description and diagram above:
(i)
outline TWO methods of removing fuel;
(2)
(ii)
identify THREE suitable types of portable extinguisher.
(3)
IOG1/S/1203 © NEBOSH 2012
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5
6
Following an annual shutdown of a process plant outline the operational control
measures that could minimise the risk of an incident before filling equipment in
preparation for start-up.
(8)
An interceptor/separator used on the surface drainage system of an oil terminal
includes safety critical control using an oil detection sensor (S) in chamber 3. The
oil detection sensor is linked to an automatic isolating valve and the control room
operating panel where an alarm is activated.
Control room
operating panel
Drain covers
Manual
isolating valve
Chamber 1
Chamber 2
Chamber 3
Oil/water inlet
to interceptor/
separator
S
Oil/water level
Oil/water level
Automatic
isolating valve
Manual
isolating valve
Oil/water level
Outlet stream
With reference to the description and diagram above:
7
8
(a)
outline how the safety critical control should prevent an incident;
(2)
(b)
outline other operational controls that could prevent an incident.
(6)
(a)
Identify THREE properties of Hydrogen Sulphide (H2S).
(3)
(b)
On an oil processing plant outline how activation of an H2S detection
system, linked to a control room, could prevent a fire.
(5)
An operator is draining a flammable liquid from process pipe work to a metal
container. The supervisor is concerned about the possibility of an electrostatic
charge forming and stops this operation until a risk assessment is undertaken.
During this work activity:
(a)
identify factors that influence the generation of the electrostatic charge;
(4)
(b)
outline practical ways of minimising the formation of an electrostatic
charge.
(4)
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9
Many major oil / gas incidents have occurred in recent years, eg Texas City,
Mumbai High.
(a)
Outline FOUR reasons why such incidents should be investigated by
employers.
(4)
Identify FOUR parties, other than the employer, who may want to
investigate these types of incident.
(4)
Identify documents that could be provided by contractors in order to demonstrate
their health and safety competence to an oil and gas industry client.
(8)
(b)
10
11
A worker has requested a permit-to-work in order to replace damaged thermal
insulation in an overhead pipe rack that runs between two plants.
(a)
Identify THREE hazards associated with this activity.
(3)
(b)
Outline control measures that should be implemented to reduce the risks
to the worker.
(5)
IOG1/S/1203 © NEBOSH 2012
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This question paper MUST be returned to NEBOSH after the examination and must NOT be copied