bizSAFE Certification Singapore Hierarchy of Risk Control Questions and Answers

Question 1

A metal fabrication workshop in Tuas has a cutting machine that generates noise levels exceeding the 85 dB(A) permissible exposure limit set by Singapore's WSH (Noise) Regulations. According to the Hierarchy of Risk Control, what is the most effective measure the company should consider first?

Accepted Answer

Replacing the noisy machine with a modern, quieter laser cutting system.

Answer

The Hierarchy of Risk Control prioritises measures that are most effective. Elimination and Substitution are at the top. Replacing the noisy machine with a quieter one (Substitution) is more effective because it removes the hazard at the source. Engineering controls (enclosures), Administrative controls (job rotation), and PPE (earplugs) are lower down the hierarchy.

Question 2

In the context of the WSH (Risk Management) Regulations, which of the following is the best example of an 'Engineering Control'?

Accepted Answer

Installing a fixed guard on the rotating blade of a saw.

Answer

Engineering controls are physical modifications to a process or equipment to isolate people from the hazard. Installing a fixed guard is a physical barrier engineered to prevent contact. A toolbox meeting is an administrative control, safety boots are PPE, and using a different paint is substitution.

Question 3

A company is developing Safe Work Procedures (SWPs) for handling chemicals in its Jurong Island facility. The implementation of these SWPs falls under which level of the Hierarchy of Risk Control?

Accepted Answer

Administrative Controls

Answer

Administrative controls are work practices or procedures that change the way people work to reduce exposure to a hazard. Safe Work Procedures (SWPs), training, and warning signs are all classic examples of administrative controls.

Question 4

A contractor is tasked with cleaning the facade of a high-rise building in the CBD. Several control measures are proposed. According to the principles promoted by Singapore's WSH Council, which of the following is considered the LEAST effective control measure?

Accepted Answer

Requiring workers to use a full-body harness and lanyard (fall arrest system).

Answer

Personal Protective Equipment (PPE), such as a fall arrest system, is the last line of defence in the Hierarchy of Controls. It does not remove the hazard (working at height) but only minimises the consequences of a fall. Elimination (cleaning from the ground), Engineering Controls (gondola), and Administrative Controls (scheduling) are all preferred over PPE.

Question 5

What is the fundamental principle behind the structure of the Hierarchy of Risk Control as emphasised in Singapore's Risk Management Code of Practice (RMCP)?

Accepted Answer

To prioritise controls that are most reliable and place the least reliance on human behaviour.

Answer

The hierarchy is structured from most to least effective. The most effective controls (Elimination, Substitution, Engineering) are designed into the process and are more reliable because they do not depend on workers following rules or using equipment correctly. Lower-level controls like administrative procedures and PPE are highly dependent on human behaviour and thus less reliable.

bizSAFE Practice Test

bizSAFE Practice Test

bizSAFE Certification Singapore Hierarchy of Risk Control Questions and Answers