wayground logo

Free Printable Worksheets

Font size

S
M
L
XL
Worksheets

Combustion and CO Safety Quiz

Total questions: 31

Worksheet time: 16mins

Name
Class
Date
1.

Which three elements are needed for combustion?

a)

Fuel, nitrogen, heat

b)

Fuel, CO₂, spark

c)

Fuel, oxygen, ignition

d)

Oxygen, steam, spark

2.

What does complete combustion of hydrocarbons produce?

a)

CO + water

b)

CO + nitrogen

c)

CO₂ + water vapour

d)

CO₂ only

3.

What is produced during incomplete combustion?

a)

CO₂

b)

Oxygen

c)

Carbon monoxide (CO)

d)

Nitrogen

4.

Which flame indicates complete combustion?

a)

Yellow floppy flame

b)

Orange flickering flame

c)

Red flame with soot

d)

Stable blue flame

5.

What does a yellow loose flame indicate?

a)

Normal operation

b)

Cooling air flow

c)

Incomplete combustion

d)

Over‑ventilation

6.

What can sooting‑up lead to?

a)

Better efficiency

b)

Reduced flame temperature

c)

Restricted combustion products flow + overheating

d)

More oxygen supply

7.

What causes CO when there isn’t enough air?

a)

Faulty spark

b)

Too much oxygen

c)

Lack of oxygen

d)

Over‑venting

8.

What is vitiated air?

a)

Clean, fresh air

b)

Impure air with high CO₂

c)

High‑temperature air

d)

Over‑oxygenated air

9.

What happens when flame hits a cold surface?

a)

Over‑oxygenation

b)

Blue flame correction

c)

Flame impingement

d)

Cooling combustion

10.

What staining appears near poorly combusting appliances?

a)

White chalk

b)

Black streaks

c)

Brown scorch/stain marks

d)

Light blue dust

11.

CO has what smell?

a)

Rotten eggs

b)

Sweet smell

c)

Musty smell

d)

No smell

12.

Less than what CO concentration can kill?

a)

10%

b)

5%

c)

2%

d)

1%

13.

CO binds with which part of blood?

a)

Platelets

b)

Plasma

c)

Haemoglobin

d)

White cells

14.

Which of these is an early CO poisoning symptom?

a)

Seizures

b)

Tension‑type headache

c)

Organ failure

d)

Blindness

15.

Which is a severe symptom?

a)

Mild cough

b)

Red eyes

c)

Loss of consciousness

d)

Tingling fingers

16.

First action with suspected CO poisoning?

a)

Give food

b)

Call an electrician

c)

Move person to ventilated area

d)

Increase heating

17.

What percent of survivors suffer long‑term issues?

a)

1%

b)

2%

c)

10%

d)

25%

18.

What is the purpose of a CO detector?

a)

Check humidity

b)

Monitor oxygen

c)

Warn of CO presence early

d)

Detect natural gas leaks

19.

A biometric detector uses what method?

a)

Vibration sensor

b)

Colour‑changing gel

c)

Sound wave detection

d)

Infrared

20.

Which is a preferred CO detector type?

a)

Propane sensor

b)

Water sensor

c)

Metal oxide or electrochemical

d)

Temperature sensor

21.

Oxygen‑to‑fuel ratio for natural gas combustion?

a)

1:1

b)

4:1

c)

2:1

d)

20:1

22.

Practical air‑to‑gas ratio needed?

a)

2:1

b)

5:1

c)

10:1

d)

20:1

23.

Approximate oxygen percentage in Earth’s atmosphere?

a)

50%

b)

21% (20% for calcs)

c)

10%

d)

30%

24.

Do room‑sealed boilers need indoor combustion air?

a)

Yes

b)

No

c)

Only at night

d)

Only when vent is closed

25.

Purpose of ventilation?

a)

Decorate wall openings

b)

Replace stale air with fresh air

c)

Increase noise

d)

Raise humidity

26.

What replaces room air for open‑flued appliances?

a)

Radiator vents

b)

External air vents or grills

c)

Ceiling fans

d)

Chimney caps

27.

Appliances under 7 kW may rely on what source?

a)

Battery fans

b)

Internal flue booster

c)

Adventitious air

d)

Ceiling diffusers

28.

Should air vents be covered?

a)

Yes

b)

Sometimes

c)

If cold

d)

No

29.

Should vents have fly screens?

a)

Yes

b)

Only winter

c)

No

d)

Optional

30.

Which regulation covers gas appliance ventilation?

a)

Part L

b)

Building Regulations Part J

c)

Part F only

d)

Gas Act 2020

31.

Which British Standard applies to flues & ventilation?

a)

BS 6891

b)

BS 5440 Part 1

c)

BS 7671

d)

BS 9251