ACS Emergency Procedures 2 — Questions and Answers
Question 1: What are the symptoms of mild to moderate carbon monoxide poisoning?
- Severe chest pain and blue lips
- Headache, dizziness, nausea, shortness of breath, and confusion — often dismissed as flu but without raised temperature (Correct answer)
- Loss of consciousness and seizures only
- Itchy skin and watery eyes
Correct answer: Headache, dizziness, nausea, shortness of breath, and confusion — often dismissed as flu but without raised temperature
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?
- A CO alarm detects smoke and should be placed on the ceiling only
- 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 (Correct answer)
- A CO alarm must be placed immediately adjacent to the gas meter
- CO alarms and smoke alarms are the same device
Correct 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
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?
- Normal condensate in a wall cavity from a condensing boiler
- Gas accumulation in an enclosed building void from a leaking underground service, requiring evacuation, isolation, and emergency response (Correct answer)
- Air trapped in the pipework causing banging noises
- A gas vent intentionally installed in a wall cavity
Correct answer: Gas accumulation in an enclosed building void from a leaking underground service, requiring evacuation, isolation, and emergency response
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)?
- Never — the gas emergency line covers all situations
- 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 (Correct answer)
- Only when the engineer cannot identify the source of a gas escape
- When the property owner is not contactable
Correct 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
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?
- Enter immediately and attempt to resuscitate the occupant
- Do not enter; call 999; ventilate if safe to do so from outside; wait for emergency services (Correct answer)
- Turn off the gas at the meter and then enter to help
- Silence the alarm first to assess whether it is a false activation
Correct answer: Do not enter; call 999; ventilate if safe to do so from outside; wait for emergency services
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.
Question 6: After gas emergency works have made a property safe, what records must the gas engineer keep?
- No records are required for emergency work
- A detailed written record of the situation found, actions taken, safety notices issued, customer communications, and any notifications made to the gas transporter or authorities (Correct answer)
- Only a receipt for any materials used
- A verbal note communicated to the customer only
Correct answer: A detailed written record of the situation found, actions taken, safety notices issued, customer communications, and any notifications made to the gas transporter or authorities
Comprehensive records of emergency gas work are essential for safety, legal liability, and regulatory purposes — they document what was found, what was done, and what notices were issued.
ACS Emergency Procedures 2
What are the symptoms of mild to moderate carbon monoxide poisoning?