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SAFETY IN WELDING
that a smoke extractor unit is used. If this is not possible, the welder must be equipped with, and must use a face shield with fresh air connection. Welding, cutting and brazing with a gas torch can produce smoke which may contain several toxic substances. Of the gases given off, it is primarily the nitrous gases (NO2 + NO) that are a health hazard. The amount of nitrous gases in the smoke depends on several conditions. The use of large size torches in confined spaces can quickly produce dangerous concentrations. No warning is given of the presence of these gases in the form of irritation of the muceous membrane in eyes, nose or throat. Proper ventilation must be arranged, and when working in confined spaces, the welder must not leave the torch alight when he is not actually using it.
Carbon monoxide may be given off due to incomplete combustion of the gases or if the material being welded or cut is plastic surfaced, varnished, painted or oily. High concentrations, which constitute a health risk, can be formed in confined spaces, tanks, pipes etc. Inhalation of large quantities of carbon monoxide can lead to suffocation. This section points out some of the more usual risks connected with welding smoke. There are special books on the subject, and welding smoke is also undergoing continuous research. The result of this research work may bring new important factors to light and all those involved in welding should keep themselves informed of the development in this area, so precautions can be taken to protect against health risks which may, as yet, be unknown.
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Avoid direct inhalation of welding fumes.
Use fume extraction.
Use Fresh Air supply.
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