Torch Basics
Safety First
Flames & Cutting
Tank & Regulator Know-How
Common Mistakes & Fixes
100

The main purpose of an oxy-acetylene torch?

Cutting or Welding Metal


100

Personal protective equipment (PPE) should be worn when using a torch?

Gloves, safety glasses, flame-resistant clothing.

100

Signs the steel is ready to cut with a torch?

Heat until red-hot, then depress the oxygen lever.

100

How do you identify the oxygen regulator?

It usually has right-hand threads and a green label.

100

What happens if you open acetylene too fast?

It may cause a loud pop or small explosion

200

The two gases used in oxy-acetylene torches?

Oxygen and acetylene.

200

Always check for what before lighting a torch?

Leaks, proper connections, and damage.

200

What should you avoid when making a cut?

Going too fast, which causes incomplete cutting.

200

How do you check for leaks around fittings?

Use a soap and water solution.

200

What’s a flashback?


Flame travels back into the torch or hose—very dangerous.

300

The color is the oxygen hose typically

Green

300

The first step in an emergency gas leak

Turn off all valves and evacuate the area

300

This type of gas regulator features a red scale on the low-pressure gauge and is designed with left-hand threads to prevent accidental connections with oxygen regulators.

What is an acetylene regulator?

300

What pressure is usually set for cutting oxygen?

30–40 psi, depending on tip and material.

300

What’s a sign of a clogged tip?

Uneven or sputtering flame.

400

Which gas is turned on first when lighting the torch?

Acetylene

400

Gas cylinder storage

Upright, secured, in a well-ventilated area away from heat.

400

What’s the main cause of a poor-quality cut?

Incorrect flame or cutting speed.

400

What tool is used to open and close cylinder valves?

Wrench

400

What causes backfire?

Touching the tip to the metal or incorrect gas pressure.

500

The acetylene must never be used above 15 psi because?

It becomes unstable and explosive above 15 psi.

500

Why do you purge the lines before lighting the torch?

To remove air or mixed gases that could cause a dangerous flashback.

500

This is the color is the inner cone of a proper neutral flame

Bright white or blue.

500

What is the function of the pressure regulator?

Reduces cylinder pressure to a usable working pressure.

500

Why should hoses be kept away from sparks and heat?

To prevent melting or explosions.