Risk Assessment & Method Statement Review Flashcards

What is a 'permit to work' system and when is it used on construction sites?

Answer: A formal authorisation system for high-risk activities such as hot work, confined space entry and electrical isolation, ensuring all precautions are in place before work starts

A permit to work (PTW) is a formal document that authorises specific high-risk activities, confirms all preconditions are met (isolation, gas testing, fire precautions etc.) and nominates the responsible person. It prevents incidents by ensuring hazards are controlled before work begins.

What is a 'dynamic risk assessment' in the context of a site supervisor's role?

Answer: The ongoing assessment of changing conditions during the working day, adapting control measures when unexpected hazards arise

Site supervisors must continuously and dynamically assess conditions throughout the day. When conditions change unexpectedly (ground conditions, weather, adjacent activities), they must adapt control measures immediately and, if necessary, stop work and revise the formal risk assessment.

When must a risk assessment be conducted?

Answer: Before the hazardous activity begins, and before any significant change to the activity or work environment

Risk assessments must be completed before the hazardous work begins so that control measures can be put in place in advance. They must be reviewed and, if necessary, revised when there is a significant change to the activity, environment or workforce.

What is the significance of PPE being at the bottom of the control hierarchy?

Answer: PPE is the last resort because it does not reduce the hazard — it only protects the individual wearer and only if worn correctly

PPE is at the bottom of the hierarchy because it does not eliminate or reduce the hazard itself — it only provides a barrier between the hazard and the wearer. It is dependent on correct selection, proper fit, wearing at all times, and correct maintenance, making it inherently less reliable than engineering controls.

What does 'likelihood × severity' produce in a risk matrix?

Answer: A risk rating that prioritises which hazards need the most urgent attention

Multiplying likelihood (probability score) by severity (consequence score) in a risk matrix produces a risk rating or risk score. Higher scores indicate greater risk and priority for control action. This helps focus resources on the most significant risks.

Why is it important for a site supervisor to ensure risk assessments are 'live' documents?

Answer: Because site conditions, methods and hazards change throughout a project and the assessment must always reflect the actual current situation

Risk assessments are only useful if they reflect the current situation. As site conditions, working methods, personnel and hazards evolve during a project, risk assessments must be reviewed and updated to remain relevant and effective.