Welding: Health and safety

Oxy-acetylene welding can be a dangerous task, The welder is exposed to heat and fumes which could harm their health, but the danger to yourself and others can be significantly reduced if you follow simple health and safety guidelines, and use the appropriate safety equipment. Having this prior knowledge can help prevent or minimise accidents in the welding workshop.

Before entering the welding workshop proper safety clothing must be worn: overalls to protect your clothes and skin from hot metals or flames, and safety boots to protect your feet from falling objects.

Before welding can begin the welding plant needs to be set up, the welding plant consists of : Oxygen bottle, Acetylene bottle, regulator valves, flashback arrestors, hoses, and a welding torch. All equipment should be kept clean away from heat or dampness.

It is important to know what the different coulors of cylinders mean, the oxygen cylinder is a black color internationally to distinguish it from the maroon or red color of the acetylene bottle.
The oxygen bottle should never be used as compressed air and oil or grease should never be on or near the regulators of the oxygen bottle as the air can react with the oil and could cause an explosion.
Acetylene cylinders are less pressurised than oxygen cylinders and are filled with liquid acetylene. they should never be used or stored on their side as the liquid acetylene can go down the hoses and cause flashback. All threads and fittings on an oxygen cylinder are right hand thread and all acetylene cylinder fittings are left hand thread this ensures there is no mix ups.

Cylinders on a trolley.

Regulator valves attacth to the top of the cylinders and regulate the oygen and acetylene in to hoses

they are used to set the pressures on the system.

oxygen and acetylene regulators

Flashback arrestors are used to prevent flames from travelling up the hoses to the regulator, when a flame is detected the supply is closed.

Welding hoses should always be stored correctly and never repared with tape or metal, blue for oxygen, Red for acetylene.

The welding torch should always be stored safely and protected from damage or jarring, this can affect the flame.

When setting up to weld there is a procedure that is to be followed:

. Check the equipment, ensure torch valves are closed

. Open the Acetylene valve fully
. Set the right pressure on the regulator for the material you are welding
. Open the Oxygen valve fully
. Set the oxygen pressure
. Open the acetylene torch valve half a turn
. Strike the torch and adjust the acetylene until most of the black smoke is gone
. adjust the oxygen until you have the flame you desire

Always wear appropriate eye prtection when gas welding, and gloves if neccesary.

Also ensure you are in a well ventilated area, and if that isn't possible then have proper extraction. Some materials when welded give off poisonous fumes so use a respirator or breathing apparatus. Always ensure the welding area is free of combustable materials.

Correct welding safety practice

When closing down a welding plant these steps should be followed:
. Exstinguish the flame by turing off the acetylene on the torch
. Turn off the oxygen at the torch
. Turn off the acetylene valve on the cylinder
. Turn off the oxygen valve at the cylinder
. Turn both regulator valves off 
. Purge the hoses by opening both valves on the torch, then closing them when the hoses are purged.


  Additional notes:
. when not using the welding torch it should be off or on a proper stand.
. When welding hot pieces of metal should be quenced or left to cool somewhere safe to prevent burns
. Don't distract people while they weld.