NEBOSH HSE PSM FINAL EXAM ACTUAL QUESTIONS AND
SOLUTIONS RATED A+
✔✔Process Hazard Analysis (PHA) - ✔✔A systematic analysis of the hazards (and their
potential causes and consequences) relevant to a particular process.
✔✔HAZOP, What-if, FMEA - ✔✔What types of techniques might a Process Hazard
Analysis use?
✔✔Answer: Process Hazard Analysis - ✔✔What should a pre-start-up safety review be
based on?
✔✔A check that all standards have been adhered to, particularly for any Safety Critical
Elements - ✔✔What key check should the Process Hazard Analysis used for pre-start-
up safety review include?
✔✔Functionality, availability, reliability, survivability, interdependency - ✔✔Acronym:
FARSI
✔✔FARSI - ✔✔A means to describe the safety performance standards for plant and
equipment, particularly in terms of Safety Critical Elements
✔✔Prevention, detection, control, mitigating - ✔✔What types of Safety Critical Elements
does FARSI describe?
✔✔Acronym: Remotely operated shutoff valve - ✔✔Acronym: ROSOV
✔✔Remotely operated shutoff valve (ROSOV) - ✔✔A shutoff valve whose operation
can be controlled from a point that is remote from the valve itself, such as in a control
room
✔✔Rapid emergency isolation of vessels, pipelines etc during e.g. major leaks -
✔✔When are ROSOVs mainly used
✔✔Acronym: uninterruptible power supply - ✔✔Acronym: UPS
✔✔Uninterruptible power supply (UPS) - ✔✔A temporary back-up power supply
installed between main power supply and critical equipment
✔✔Battery powered - ✔✔How do UPS' usually function?
✔✔alarm to alert workers to the power outage - ✔✔What function additional to providing
uninterruptible power to critical equipment might a UPS have?
, ✔✔Acronym: Probability of failure on demand - ✔✔Acronym: PFD
✔✔Probability of failure on demand (PFD) - ✔✔the probability that a component will fail
to perform its safety function at the time it is needed
✔✔Answer: Probability of failure on demand (PFD) - ✔✔In what terms is the 'reliability'
measure of FARSI often expressed?
✔✔Acronym: Mean Time Between Failure - ✔✔Acronym: MTBF
✔✔Mean Time Between Failures (MTBF) - ✔✔The calculated average time that elapses
between failures of a system, equipment or a component.
✔✔Answer: Mean time between failures (MTBF) - ✔✔What is the measure used in
relation to predicted failures of repairable systems?
✔✔Acronym: Safety instrumented system - ✔✔Acronym: SIS
✔✔Safety Instrumented System (SIS) - ✔✔An instrumented system used to implement
either a safety control or protection function (or both)
✔✔Sensor(s), logic solver(s) and final element(s) - ✔✔What three connected
components make up a SIS?
✔✔logic solver - ✔✔Which component of a SIS decides what action to take depending
on the sensor input
✔✔Final element - ✔✔Which component of a SIS carries out the physical action (e.g.
valve)?
✔✔Acronym: Safety integrity level - ✔✔Acronym: SIL
✔✔Safety Integrity Level (SIL) - ✔✔The specified levels of safety integrity a SIS needs
to have
✔✔Level 1 (lowest) to Level 4 (highest) - ✔✔What are the levels of the SIL system?
✔✔Safety integrity of SIS - ✔✔The average probability of a SIS performing its function
(under stated conditions for a certain period of time)
✔✔Saturated steam - ✔✔Steam that is still wet
✔✔3-5% - ✔✔What percentage of water remains in saturated steam?
SOLUTIONS RATED A+
✔✔Process Hazard Analysis (PHA) - ✔✔A systematic analysis of the hazards (and their
potential causes and consequences) relevant to a particular process.
✔✔HAZOP, What-if, FMEA - ✔✔What types of techniques might a Process Hazard
Analysis use?
✔✔Answer: Process Hazard Analysis - ✔✔What should a pre-start-up safety review be
based on?
✔✔A check that all standards have been adhered to, particularly for any Safety Critical
Elements - ✔✔What key check should the Process Hazard Analysis used for pre-start-
up safety review include?
✔✔Functionality, availability, reliability, survivability, interdependency - ✔✔Acronym:
FARSI
✔✔FARSI - ✔✔A means to describe the safety performance standards for plant and
equipment, particularly in terms of Safety Critical Elements
✔✔Prevention, detection, control, mitigating - ✔✔What types of Safety Critical Elements
does FARSI describe?
✔✔Acronym: Remotely operated shutoff valve - ✔✔Acronym: ROSOV
✔✔Remotely operated shutoff valve (ROSOV) - ✔✔A shutoff valve whose operation
can be controlled from a point that is remote from the valve itself, such as in a control
room
✔✔Rapid emergency isolation of vessels, pipelines etc during e.g. major leaks -
✔✔When are ROSOVs mainly used
✔✔Acronym: uninterruptible power supply - ✔✔Acronym: UPS
✔✔Uninterruptible power supply (UPS) - ✔✔A temporary back-up power supply
installed between main power supply and critical equipment
✔✔Battery powered - ✔✔How do UPS' usually function?
✔✔alarm to alert workers to the power outage - ✔✔What function additional to providing
uninterruptible power to critical equipment might a UPS have?
, ✔✔Acronym: Probability of failure on demand - ✔✔Acronym: PFD
✔✔Probability of failure on demand (PFD) - ✔✔the probability that a component will fail
to perform its safety function at the time it is needed
✔✔Answer: Probability of failure on demand (PFD) - ✔✔In what terms is the 'reliability'
measure of FARSI often expressed?
✔✔Acronym: Mean Time Between Failure - ✔✔Acronym: MTBF
✔✔Mean Time Between Failures (MTBF) - ✔✔The calculated average time that elapses
between failures of a system, equipment or a component.
✔✔Answer: Mean time between failures (MTBF) - ✔✔What is the measure used in
relation to predicted failures of repairable systems?
✔✔Acronym: Safety instrumented system - ✔✔Acronym: SIS
✔✔Safety Instrumented System (SIS) - ✔✔An instrumented system used to implement
either a safety control or protection function (or both)
✔✔Sensor(s), logic solver(s) and final element(s) - ✔✔What three connected
components make up a SIS?
✔✔logic solver - ✔✔Which component of a SIS decides what action to take depending
on the sensor input
✔✔Final element - ✔✔Which component of a SIS carries out the physical action (e.g.
valve)?
✔✔Acronym: Safety integrity level - ✔✔Acronym: SIL
✔✔Safety Integrity Level (SIL) - ✔✔The specified levels of safety integrity a SIS needs
to have
✔✔Level 1 (lowest) to Level 4 (highest) - ✔✔What are the levels of the SIL system?
✔✔Safety integrity of SIS - ✔✔The average probability of a SIS performing its function
(under stated conditions for a certain period of time)
✔✔Saturated steam - ✔✔Steam that is still wet
✔✔3-5% - ✔✔What percentage of water remains in saturated steam?
