What substance should you NEVER apply to a stiff pressure-adjusting screw on an oxygen regulator?

The use of oil or grease on a stiff pressure-adjusting screw of an oxygen regulator is highly dangerous and should always be avoided. Oxygen is a powerful oxidizer, which means it can dramatically increase the combustion potential of materials that are flammable or combustible. When oil or grease is applied to any part of an oxygen system, there is a risk that even a small spark could ignite the oil, leading to explosive reactions.

In high-pressure oxygen environments, the presence of hydrocarbons (like those found in oils and greases) can create a significant safety hazard. Therefore, safety protocols specifically prohibit the use of oil or grease in any contact with oxygen equipment. Instead, lubricant alternatives that are safe for oxygen service, such as certain types of fluorinated or silicone-based lubricants, should be utilized, if needed.

Understanding this principle is crucial for ensuring safety in welding and related activities, where oxygen regulators are commonly used. Maintaining proper safety procedures when dealing with oxygen equipment is essential to prevent accidents and injuries.