NEBOSH HSE PSM QUESTIONS WITH
COMPLETE SOLUTIONS
Course
NEBOSH
1. Question:
Explain the purpose of a Process Hazard Analysis (PHA) and give two examples of PHA
techniques.
Answer:
The purpose of a Process Hazard Analysis (PHA) is to identify and assess potential hazards
associated with industrial processes, particularly in high-risk industries like chemical or oil and
gas sectors. It systematically examines the processes to predict what could go wrong and how to
mitigate it.
Examples of PHA techniques:
HAZOP (Hazard and Operability Study): Structured, team-based approach focusing
on deviations from design intent.
What-If Analysis: Brainstorming approach asking "what if" questions to explore
possible failures.
2. Question:
List four critical elements of a Process Safety Management (PSM) system.
Answer:
The four critical elements are:
Process Safety Leadership: Commitment from top management to prioritize process
safety.
Risk Management: Identification, assessment, and control of risks through tools like
PHA.
Competence: Ensuring employees and contractors are trained and skilled.
Management of Change (MoC): Formal processes to evaluate risks associated with any
modifications.
3. Question:
Describe what is meant by 'Inherently Safer Design' (ISD) and provide two examples.
,Answer:
Inherently Safer Design (ISD) means designing processes to eliminate or significantly reduce
hazards, rather than controlling hazards with add-on systems.
Examples:
Substitution: Using a less hazardous chemical (e.g., water-based paints instead of
solvent-based).
Minimization: Reducing the quantity of hazardous substances used or stored.
4. Question:
Why is it important to have effective emergency planning and response procedures in place for
process industries?
Answer:
Effective emergency planning ensures:
Rapid and organized response during incidents.
Minimization of harm to people, environment, and assets.
Compliance with legal and regulatory requirements.
Clear roles and responsibilities to avoid confusion during crises.
5. Question:
Identify three types of failures that could occur in a Safety Critical Element (SCE) and briefly
describe each.
Answer:
Demand Failure: When an SCE fails to perform its safety function upon demand (e.g.,
sprinkler system doesn't activate during a fire).
Degraded Failure: When an SCE continues operating but its performance is reduced
(e.g., partially blocked relief valve).
Hidden Failure: A failure that is not immediately obvious and only becomes apparent
when the SCE is tested or needed (e.g., a stuck valve).
6. Question:
,Explain the concept of "layers of protection" in process safety and give an example.
Answer:
"Layers of protection" refers to multiple, independent safety barriers that prevent or mitigate
hazardous events. Each layer is intended to prevent escalation if a preceding layer fails.
Example:
Process design → Control systems → Alarms and operator intervention → Relief devices
→ Emergency response.
7. Question:
What is the purpose of Management of Change (MoC) in process industries, and what are two
key steps in the MoC process?
Answer:
The purpose of MoC is to ensure that any changes to processes, equipment, or personnel are
reviewed, assessed for risk, and properly authorized before implementation.
Two key steps:
Risk Assessment: Analyze the potential hazards introduced by the change.
Communication and Training: Ensure affected personnel understand the change and
any new procedures.
8. Question:
Describe two reasons why it is important to investigate near-misses in process industries.
Answer:
Proactive Prevention: Near-misses indicate potential weaknesses in controls and allow
corrective actions before an accident happens.
Learning Opportunity: Organizations can learn and improve systems by understanding
why the near-miss occurred without suffering a major loss.
9. Question:
What is the role of competence assurance in process safety management, and how can
competence be maintained?
, Answer:
Competence assurance ensures that workers have the necessary skills, knowledge, and
experience to perform tasks safely and effectively.
Competence can be maintained through:
Regular training and refresher courses.
On-the-job assessments and audits.
Certification and re-certification where applicable.
10. Question:
Define "Process Safety Culture" and list three indicators of a strong process safety culture.
Answer:
Process Safety Culture refers to the shared attitudes, values, and behaviors that prioritize and
promote process safety across all levels of an organization.
Three indicators of a strong culture:
Leadership visibly prioritizes safety over production.
Open reporting and discussion of near-misses and hazards.
Continuous improvement through learning from incidents.
11. Question:
What is meant by the term "safety critical equipment"? Give two examples.
Answer:
Safety critical equipment (SCE) refers to any device, system, or structure whose failure could
cause or contribute substantially to a major accident or whose purpose is to prevent or mitigate a
major accident.
Examples:
Pressure relief valves.
Emergency shutdown (ESD) systems.
12. Question:
State three reasons why accurate information about hazardous substances is important in process
industries.
Answer:
COMPLETE SOLUTIONS
Course
NEBOSH
1. Question:
Explain the purpose of a Process Hazard Analysis (PHA) and give two examples of PHA
techniques.
Answer:
The purpose of a Process Hazard Analysis (PHA) is to identify and assess potential hazards
associated with industrial processes, particularly in high-risk industries like chemical or oil and
gas sectors. It systematically examines the processes to predict what could go wrong and how to
mitigate it.
Examples of PHA techniques:
HAZOP (Hazard and Operability Study): Structured, team-based approach focusing
on deviations from design intent.
What-If Analysis: Brainstorming approach asking "what if" questions to explore
possible failures.
2. Question:
List four critical elements of a Process Safety Management (PSM) system.
Answer:
The four critical elements are:
Process Safety Leadership: Commitment from top management to prioritize process
safety.
Risk Management: Identification, assessment, and control of risks through tools like
PHA.
Competence: Ensuring employees and contractors are trained and skilled.
Management of Change (MoC): Formal processes to evaluate risks associated with any
modifications.
3. Question:
Describe what is meant by 'Inherently Safer Design' (ISD) and provide two examples.
,Answer:
Inherently Safer Design (ISD) means designing processes to eliminate or significantly reduce
hazards, rather than controlling hazards with add-on systems.
Examples:
Substitution: Using a less hazardous chemical (e.g., water-based paints instead of
solvent-based).
Minimization: Reducing the quantity of hazardous substances used or stored.
4. Question:
Why is it important to have effective emergency planning and response procedures in place for
process industries?
Answer:
Effective emergency planning ensures:
Rapid and organized response during incidents.
Minimization of harm to people, environment, and assets.
Compliance with legal and regulatory requirements.
Clear roles and responsibilities to avoid confusion during crises.
5. Question:
Identify three types of failures that could occur in a Safety Critical Element (SCE) and briefly
describe each.
Answer:
Demand Failure: When an SCE fails to perform its safety function upon demand (e.g.,
sprinkler system doesn't activate during a fire).
Degraded Failure: When an SCE continues operating but its performance is reduced
(e.g., partially blocked relief valve).
Hidden Failure: A failure that is not immediately obvious and only becomes apparent
when the SCE is tested or needed (e.g., a stuck valve).
6. Question:
,Explain the concept of "layers of protection" in process safety and give an example.
Answer:
"Layers of protection" refers to multiple, independent safety barriers that prevent or mitigate
hazardous events. Each layer is intended to prevent escalation if a preceding layer fails.
Example:
Process design → Control systems → Alarms and operator intervention → Relief devices
→ Emergency response.
7. Question:
What is the purpose of Management of Change (MoC) in process industries, and what are two
key steps in the MoC process?
Answer:
The purpose of MoC is to ensure that any changes to processes, equipment, or personnel are
reviewed, assessed for risk, and properly authorized before implementation.
Two key steps:
Risk Assessment: Analyze the potential hazards introduced by the change.
Communication and Training: Ensure affected personnel understand the change and
any new procedures.
8. Question:
Describe two reasons why it is important to investigate near-misses in process industries.
Answer:
Proactive Prevention: Near-misses indicate potential weaknesses in controls and allow
corrective actions before an accident happens.
Learning Opportunity: Organizations can learn and improve systems by understanding
why the near-miss occurred without suffering a major loss.
9. Question:
What is the role of competence assurance in process safety management, and how can
competence be maintained?
, Answer:
Competence assurance ensures that workers have the necessary skills, knowledge, and
experience to perform tasks safely and effectively.
Competence can be maintained through:
Regular training and refresher courses.
On-the-job assessments and audits.
Certification and re-certification where applicable.
10. Question:
Define "Process Safety Culture" and list three indicators of a strong process safety culture.
Answer:
Process Safety Culture refers to the shared attitudes, values, and behaviors that prioritize and
promote process safety across all levels of an organization.
Three indicators of a strong culture:
Leadership visibly prioritizes safety over production.
Open reporting and discussion of near-misses and hazards.
Continuous improvement through learning from incidents.
11. Question:
What is meant by the term "safety critical equipment"? Give two examples.
Answer:
Safety critical equipment (SCE) refers to any device, system, or structure whose failure could
cause or contribute substantially to a major accident or whose purpose is to prevent or mitigate a
major accident.
Examples:
Pressure relief valves.
Emergency shutdown (ESD) systems.
12. Question:
State three reasons why accurate information about hazardous substances is important in process
industries.
Answer:
