Supplied Air Respirator for Sandblasting

[1993_VG30E_GXE]

So after much reading it appears the NIOSH P100 half mask is not qualified for use for silica sand blasting. I know someones going to say 'just use another media' - not really possible since it's outdoors, high pressure, and it flies everywhere.

So I've been researching supplied air systems. I can break it down to this:

1. Hood Assembly
2. Air Control Device
3. Air Line Hose
4. Air Source

Here's the manufacturer I've been looking at:

www.allegrosafety.com

Question to you guys is, I want to use the air source from my compressor that is also feeding the pressurized sandblaster. At the sandblaster there is a Milton quick disconnect (Female), then a ball valve, then a water trap filter, then a regulator...ultimately leading to the pressure pot with the sand in it.

My question is, if I make a T-junction before the Milton disconnect, then use that air to feed the 'supplied air hood' that I'll be wearing, can the dust from the silica sand travel BACKWARDS past the water trap then into the T-junction which will go off to supply my hood?

I want to do it this way as it will avoid having a 150 ft hose going all the way to the compressor (which is indoors inside the house). Instead I can have a short hose Teed off before the Pressure Sandblaster.

 

[tom slick]

Will you still have enough air flow to the blaster if you bleed some off for the hood?

 

[spackard]

Not supposed to breath that kind of air.
Here's a link for medical-grade air:
http://www.nda.ox.ac.uk/wfsa/html/u13/u1302_01.htm

Medical grade air should be free from toxic products, flammable or toxic vapours, and odours at all points in the pipeline system. Although it is not sterile medical grade air is clean and at STP(standard temperature and pressure) should not contain more than:

0.5mg of particulate oil mist /cubic metre of air
5.5mg of carbon monoxide/ cubic metre of air
900 mg carbon dioxide/ cubic metre of air
no moisture
no bacterial contamination

 

[MarkM66]

Are you going to be doing this as a business?

If you just have a few things that need blasted, just have a pro do it, it's not that expensive.

Or get a full face respirator with a HEPA filter.

 

[The_Eric]

Originally Posted By: spackard
Not supposed to breath that kind of air.
Here's a link for medical-grade air:
http://www.nda.ox.ac.uk/wfsa/html/u13/u1302_01.htm

Medical grade air should be free from toxic products, flammable or toxic vapours, and odours at all points in the pipeline system. Although it is not sterile medical grade air is clean and at STP(standard temperature and pressure) should not contain more than:

0.5mg of particulate oil mist /cubic metre of air
5.5mg of carbon monoxide/ cubic metre of air
900 mg carbon dioxide/ cubic metre of air
no moisture
no bacterial contamination



Actually you can, but you have to have a system ($$$) to remove the oil and other impurities. We had one for our blast and paint booths..

 

[1993_VG30E_GXE]

I called a blast supply place and they said in Canada you can't use silica inside a shop anymore. He said the rule doesn't apply outdoors though IF you can contain the dust etc..

I then found out that Black Beauty (Aluminum Oxide) can be bought in 55 lb bags for cheaper than the silica. He claims that an ordinary P100 half mask filter is more than enough for using the Aluminum Oxide.

Curious your thoughts on this. I'm just going to ditch the silica idea. I wasn't aware that this stuff was so cheap.