Compressed air pipes

Avoid problems with pneumatic tools and compressed air

Pneumatic tools are commonly used on construction sites, usually with portable compressors. And it’s the rare manufacturing plant that doesn’t have a compressed air system, and with it a variety of equipment that runs on compressed air. This equipment includes not only pneumatic hand tools, but also actuating cylinders, air motors and other equipment on which production relies.

A common misconception is that what comes out of a nozzle on a compressed air hose is just air. It is almost always a mixture of air and oil, although there are oil-free systems. If compressed air is regularly released into an occupied space (for example, an assembly line with human operators), adequate ventilation must be provided.

You never blow this air on yourself to cool, dry or clean yourself. It’s partly because of the oil; not only will you breathe in the oil, but you can inject it deep under your skin with painful and deadly results such as an embolism.

The standard pressure on these systems is traditionally 80 psi. But for safety reasons, this can be reduced to 40 psi. Don’t be fooled; a blast from a 40 psi nozzle four inches from your eardrum will rupture it. And you can still push material through your skin.

The solution would seem to be to lower the system pressure to a level where no one can get hurt but the tools still work. Where would it be, exactly? At 12 psi, air from a nozzle can knock an eyeball out of its socket. Even at 4 psi, this can cause a fatal injury; an old shop prank is to “goosing” someone with a blow of air. However, 4 psi can rupture a person’s intestines.

In short, there is danger in any useful pressure. Treat an air tool or nozzle like a loaded gun; never point it at anyone.

Some other security practices:

  • Wear safety glasses (with side shields) or safety glasses whenever air tools are used near you. It doesn’t matter if you don’t use them personally; compressed air won’t.
  • Treat compressed air hoses as test leads; inspect them carefully before using them. Do not attempt to repair damage with duct tape. Replace the entire hose or use an approved repair method such as cutting out the damaged portion and joining the ends with approved fittings.
  • Make sure the fittings are tight; this includes quick connectors.
  • Never pinch or bend (bend) an air hose to regulate or stop airflow. This can lead to a pipe rupture with horrific consequences.

Air tools have a long history of being widely used in manufacturing. They are also used on construction sites. They are sometimes the tool of choice over a battery or mains powered tool, especially in hazardous areas. Just as compressed air is not “free” (it costs more per unit of work than electricity), neither is it safe.