How to be Properly Paranoid about the Quality of your Supplied Air

It would be so easy for abrasive media blasters to purchase a top-of-the-line supplied air helmet, succumb to a false sense of security, and never give their air supply another thought.

I suspect this happens a lot.

To be clear, I do recommend investing in a supplied air helmet. At Kaser, we use the RPB Nova 3 blast helmet, and it’s excellent. But if anything, knowing that Stan is breathing supplied air makes me more vigilant, not less.

Why? Because Stan is only as safe as his air supply, and I’m responsible for the quality of that air supply.

When I ordered the Nova 3 blast helmet, I also ordered the RPB Radex compressed breathing air filter unit and a carbon monoxide monitor. Both features are helpful – the Radex filter mitigates moisture, odor, and particulates, and the monitor alarms when CO levels get too high. These precautions are not enough, however.

Shop managers, take note: you need to be drying and filtering your breathing air before it ever reaches the compressed breathing air filter. This means investing in more filters, and maintaining those filters as though your employee’s life depends on it (because it does).

Per OSHA, “grade D” breathable air must meet the following requirements:

• • Oxygen content of 19.5 – 23.5 percent
  • Condensed Hydrocarbon (oil mist) content of 5 mg per cubic meter of air or less
  • Carbon monoxide content of 10 parts per million or less
  • Carbon dioxide content of 1,000 parts per million or less
  • Lack of noticeable odor

Your setup from RPB – as nice as it is – doesn’t guarantee you grade D air. You can’t supply it with hot, oily air and expect it to work miracles.

Of course, the manager’s best efforts are futile if the operator does not take responsibility for their own safety. Train your operators to follow these steps each and every time they blast:

1. 1. Check the compressed breathing air filter regulator gauge to ensure adequate air flow.
   2. Check the CO monitor. Carbon monoxide levels should be less than 10 parts per million.
   3. Ensure that the breathing tube is connected to the filter outlet on one end, and the helmet – or the climate control device – on the other.
   4. Remove the blast helmet at the first sign of any odor, and contact the safety manager.

There are a lot of shop routines about which we grow complacent overtime. Breathing air maintenance cannot be one of them.