ACS Emergency Procedures 2

Question 1

What are the symptoms of mild to moderate carbon monoxide poisoning?

Accepted Answer

Headache, dizziness, nausea, shortness of breath, and confusion — often dismissed as flu but without raised temperature

Answer

Mild CO poisoning causes headache, dizziness, nausea, and confusion — symptoms often improve when leaving the building and worsen on return, which is a key diagnostic indicator.

Question 2

How is a CO alarm different from a smoke alarm, and where should it be positioned?

Accepted Answer

A CO alarm detects carbon monoxide gas and should be positioned at breathing height (1–1.5 metres) in a room with a gas appliance, as CO mixes evenly with air

Answer

CO mixes evenly with air (unlike smoke, which rises) so CO alarms should be at or near head height; BS EN 50291 governs CO alarm standards and their placement in rooms with gas appliances.

Question 3

What does 'gas in void' mean and what is the appropriate emergency response?

Accepted Answer

Gas accumulation in an enclosed building void from a leaking underground service, requiring evacuation, isolation, and emergency response

Answer

Gas accumulating in a building void from a leaking buried service is extremely dangerous — it can migrate unseen and ignite from any spark; evacuation of the building and calling the gas emergency service are immediate priorities.

Question 4

When should a Gas Safe engineer consider calling emergency services (999) rather than just the gas emergency line (0800 111 999)?

Accepted Answer

When there are injured persons, unconscious occupants, a fire, or an explosion has occurred — 999 covers fire, ambulance, and police as well as gas emergencies

Answer

999 must be called when there is immediate risk to life — injuries, fire, explosion, or unconscious persons — as well as 0800 111 999 for the gas emergency, so multiple services respond simultaneously.

Question 5

What is the correct action if a gas engineer arrives at a property and finds an occupant unconscious with a CO alarm sounding?

Accepted Answer

Do not enter; call 999; ventilate if safe to do so from outside; wait for emergency services

Answer

An unconscious person in a CO-filled building represents a serious risk — the engineer must not enter without breathing apparatus, must call 999 immediately, and ventilate if possible from outside while waiting for trained responders.

Gas Safe ACS Practice Test

Gas Safe ACS Practice Test

ACS Emergency Procedures 2