I am not an expert on welding and torch cutting so I cannot answer your question specifically. However, I can recommend that you consult professional organizations such as the American Welding Society (AWS) for further information. AWS is a source for numerous technical publications on welding and cutting and many of the safety related publications are free of charge. One place to start might be AWS/ANSI Standard  Z49.1 "Safety in Welding, Cutting, and Allied Processes" which is available for no cost at the AWS website (http://www.aws.org/safety/).