WELDER TRAINING

INFORMATION

Oxy-Fuel Gas Equipment Safety Test

This test paper is in accordance with the Training Manual TM/TRS/001/TMT Issue 2 March 1990. The passmark is 80%; duration 1 hour. When you have completed the 15 questions use the buttons at the bottom to see how you have performed.

1. What colour are Oxygen cylinders painted and which thread are the outlet connections screwed?

Red, with right-hand screwed connections
Black, with right-hand screwed connections
Maroon, with right-hand screwed connections
Black, with left-hand screwed connections
Maroon, with left-hand screwed connections

2. What colour are cylinders containing Dissolved Acetylene painted and which thread are the outlet connections screwed?

Maroon, with left-hand screwed connections
Black, with left-hand screwed connections
Red, with left hand screwed connections
Black, with right-hand screwed connections
Maroon, with right-hand screwed connections

3. What colour are cylinders containing Propane painted and which thread are the outlet connections screwed?

Maroon, with left-hand screwed connections
Black, with left-hand screwed connections
Red, with left hand screwed connections
Black, with right-hand screwed connections
Maroon, with right-hand screwed connections

4. Which of the following statements are correct?

	An Acetylene/Air or Acetylene/Oxygen mixture could explode if approximately 2% to 82% Acetylene were present
	Acetylene alone is liable to explode if subject to high pressure
	Pure Oxygen burns fiercely
	Pure Oxygen makes no difference at all to the rate at which substances burn
	Grease and oil will burn spontaneously in the presence of Oxygen under pressure
	All cylinder spindles have left-hand threads
	Gas may be transferred from one cylinder to another

5. Cylinders are to be handled by TWO of the following:

Rolling or sliding along a rail
By the use of a magnet, provided that the cylinder is empty
With a hook and chain sling
Using a webbing sling
With the cylinder valves open on empty cylinders
Using a wheeled cylinder trolley

6. After being transported in the horizontal position, how long, in minutes must a cylinder containing Dissolved Acetylene be allowed to stand upright before being used?

30 minutes
15 minutes
20 minutes
10 minutes

7. What action MUST be taken if a cylinder leaks and the leak cannot be corrected by tightening the nut on the valve gland, or the bull nosed connection, or other approved methods?

	The facts of the leak must be chalked on the cylinder
	The leaking cylinder must be painted bright red
	The cylinder must be removed to the open air
	The cylinder must be covered over until inspected by the supplier
	The facts must be reported to the Supervisor
	A written report must be made
	Smoking and naked lights must be forbidden near the leaking cylinder

8. If a cylinder becomes heated for any reason, which THREE actions below MUST be taken?

All personnel must be cleared at once from the vicinity of the cylinder
Personnel not immediately involved in the work being carried out must be moved away from the cylinder
Switch off the cylinder and apply water in the form of a fine spray to cool the cylinder provided that this can be done in safety
Do not use water to cool an overheated cylinder
The Supervisor must be notified of the situation immediately
The Supervisor must be notified, in writing, of the incident in due course

9. What method is to be used to test for leaks on cylinder valves, regulators and all connections?

Apply 0.5% Teepol solution in water with a brush or an approved leak detection spray and look for any bubbles that may appear
Listen carefully for the sound of gas escaping from the regulators or connections
Look carefully for signs of gas escaping from the regulators and connections and causing movement in dust particles in the air
Apply salty water with a brush and look for evidence of escaping gas

10. Oxygen hose connections and hose check valves can be recognised because they have:

Plain nuts with right-hand threads
Plain nuts with left-hand threads
Notched nuts with right-hand threads
Notched nuts with left-hand threads

11. May a pressure gauge made for use with Propane be used for Acetylene?

No, not in any circumstances
Yes, if it will fit and does not leak
No, unless authorised by a Welding Supervisor
Yes, if the job is an emergency

12. What must an operator do first if sparks issue from the blowpipe nozzle?

Immediately close the blowpipe oxygen valve and then the blowpipe fuel gas valve
Check the gas pressures and the tightness and condition of the nozzle
Inspect the blowpipe, gas hoses, and connections for damage, defects or leaks before re-lighting
Cut off the gas supplies, quickly, by kinking or squeezing the hoses and then re-light the blowpipe

13. Flame 'snap-out', backfires and flashbacks have a number of similar causes. From the list below, select FOUR.

Overheating of the nozzle caused by improper handling of the blowpipe
Blowpipe being held too far away from the surface of the material being cut, so that the flame is dissipated
Gas leaking from the nozzle/blowpipe head joints caused by loose, dirty or damaged components
Insufficient gas pressure for the size of nozzle being used
Excessive gas pressure for the size of nozzle being used
Choking of the orifices caused by metal particles sticking to the blowpipe nozzle, or touching the workpiece with the nozzle
High winds causing gases to eddy about in the vicinity of the blowpipe nozzle
Too short a length of hose between the gas cylinders and the blowpipe

14. How should Gas pressures be regulated?

At the torch valves
Changing the nozzle size
Adjusting at the regulators
Adjusting the cylinder valve

15. What colour hoses should be used for the gases listed?

Acetylene
Propane
Oxygen

The pass mark is 80%. Any less implies it is not safe for you to use Oxy-Fuel Gas Equipment and should consider attending one of our courses.