Safety Recommendations for Gas Welding
Welding and cutting of metals involve the application of intense heat to the objects being welded or cut. This intense heat in welding is obtained from the use of inflammable gases, (e.g. acetylene, hydrogen, etc.) or electricity. The intense welding heat and the sources employed to produce it can be potentially hazardous. Therefore, to protect persons from injury and to protect building and equipment against fire, etc., a set of recommendations concerning safety and health measures for the welders and those concerned with the safety of the equipments etc., have been published by BIS and many other similar but International organizations. By keeping in mind these recommendations or precautions, the risks associated with welding can be largely reduced. Therefore, it is suggested that the beginner in the field of gas welding must go through and become familiar with these general safety recommendations, which are given below.
1. Never hang a torch with its hose on regulators or cylinder valves.
2. During working, if the welding tip becomes overheated it may be cooled by plunging the torch into water; close the acetylene valve but leave a little oxygen flowing.
3. Always use the correct pressure regulators for a gas. Acetylene pressure regulator should never be used with any other gas.
4. Do not move the cylinder by holding the pressure regulator and also handle pressure regulators carefully.
5. Use pressure regulator only at pressures for which it is intended.
6. Open cylinder valves slowly to avoid straining the mechanism of pressure regulator.
7. Never use oil, grease or lubricant of any kind on regulator connections.
8. For repairs, calibrations and adjustments purposes, the pressure regulators should be sent to the supplier.
9. Do cracking before connecting pressure regulator to the gas cylinder.
10. Inspect union nuts and connections on regulators before use to detect faulty seats which may cause leakage of gas when the regulators are attached to the cylinder valves.
11. Hose connections shall be well fittings and clamped properly otherwise securely fastened to these connections in such a manner as to withstand without leakage a pressure twice as great as the maximum delivery pressure of the pressure regulators provided on the system.
12. Protect the hose from flying sparks, hot slag, hot workpiece and open flame. If dirt goes into hose, blow through (with oxygen, not acetylene) before coupling to torch or regulator.
13. Store hose on a reel (an automobile wheel) when not in use.
14. Never allow the hose to come into contact with oil or grease; these deteriorate the rubber and constitute a hazard with oxygen.
15. Use the correct color hose for oxygen (green/black) and acetylene (red) and never use oxygen hose for acetylene or vice versa.
16. Always protect hose from being trampled on or run over. Avoid tangle and kinks. Never leave the hose so that it can be tripped over.
Hazards of fumes, gases and dusts can be minimized by (i) improving general ventilation of the place where welding is carried out (ii) using local exhaust units, and (iii) wearing individual respiratory protective equipment.
Source A Textbook of Basic Manufacturing Processes and Workshop Technology by Rajender Songh.
