GRP Piping For Breathing Air
GRP Piping For Breathing Air
(OP)
Owing to the need to avoid metallic piping for burial within a complex plant, there is a need to use non-metallic piping for a breathing air distribution header. We are very experienced with the design and installation of GRP but are being steered towards thermoplastic piping because there is "no breathing air certification" for GRP. As far as I can tell, there is no specific 'certification' of any material for breathing air - it simply must not impart an odour or otherwise taint the air. Does anybody have experience of employing GRP in breathing air systems?
Steve Jones
Materials & Corrosion Engineer
http://www.pdo.co.om/pdoweb/





RE: GRP Piping For Breathing Air
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· Tubing shall be stainless steel complying with ASTM A269, or other
approved materials that are compatible with breathing air at the system
pressure.
· Routing of tubing and bends shall be such as to protect the tubing from
mechanical damage.
· Fittings shall be constructed of stainless steel complying with ASTM
A479, or other approved materials that are compatible with breathing air
at the system pressure.
· The use of nonmetallic materials, carbon steel, iron pipe, malleable iron,
high-strength gray iron, or alloy steel shall be prohibited for breathing air
pipe and tubing materials.
NOTE THE REQUIREMENT FOR 5000 PSI,
http://virtualpipeline.spaces.msn.com
"We can't solve problems by using the same kind of thinking we used when we created them." -Albert Einstein
RE: GRP Piping For Breathing Air
Mike Halloran
Pembroke Pines, FL, USA
RE: GRP Piping For Breathing Air
http://virtualpipeline.spaces.msn.com
"We can't solve problems by using the same kind of thinking we used when we created them." -Albert Einstein
RE: GRP Piping For Breathing Air
RE: GRP Piping For Breathing Air
Steve Jones
Materials & Corrosion Engineer
http://www.pdo.co.om/pdoweb/
RE: GRP Piping For Breathing Air
http://virtualpipeline.spaces.msn.com
"We can't solve problems by using the same kind of thinking we used when we created them." -Albert Einstein
RE: GRP Piping For Breathing Air
There is also an added comment that Galvanized Pipe shall not be used in any part of the system, peroid.
Our plant wide system is now all 316L with brass/ss quick connects with hose break valves.
The comment on galvanized pipe came from us getting in trouble as several checks on filter sampler revealed traces of lead above the permissible level.
RE: GRP Piping For Breathing Air
Thanks for all your contributions.
Steve Jones
Materials & Corrosion Engineer
http://www.pdo.co.om/pdoweb/
RE: GRP Piping For Breathing Air
RE: GRP Piping For Breathing Air
http://virtualpipeline.spaces.msn.com
"We can't solve problems by using the same kind of thinking we used when we created them." -Albert Einstein
RE: GRP Piping For Breathing Air
Steve Jones
Materials & Corrosion Engineer
http://www.pdo.co.om/pdoweb/
RE: GRP Piping For Breathing Air
http://virtualpipeline.spaces.msn.com
"We can't solve problems by using the same kind of thinking we used when we created them." -Albert Einstein
RE: GRP Piping For Breathing Air
Steve Jones
Materials & Corrosion Engineer
http://www.pdo.co.om/pdoweb/
RE: GRP Piping For Breathing Air
You're using an on-line forum and we're trying to be helpful to you. You should not be surprised to get some opinions which you feel to be "unqualified"- you're the one asking the question here instead of at ASHRAE or some association of industrial hygienists etc. which specialize in the topic at hand. Most of us come here to learn and to be helpful in whatever way we can as a means of recompense for what we've learned.
I hear you about the "best practices hobby horse". Too many engineers use codes, standards and company procedures to avoid doing any engineering whatsoever. Ignoring the standards and proceeding blindly is more dangerous still, but the use of standards as a crutch by engineers drives me nuts. Standards should be written to give design guidance to engineers rather than trying to provide a perscription to non-enigneers of how to do an engineer's work which then PRECLUDES the use of engineering to obtain a more optimal solution. Merely reading and applying the corporate standards is sensible I guess if that's what you're being paid by your firm to do, but it's a real PITA when you come across a situation clearly not anticipated in the standards and all the helpful advice these standard-slingers can offer is, "Tell me where in the standard it says you can DO that!".
I've never had to design a multi-user breathing air system so I've never reviewed the standards. In your review of applicable design guidance (ie. as opposed to the Newport Beach thing which is clearly for filling SCBA tanks), are point of use filters for oil and particulates actually permitted? The only supplied air systems I've seen had no point of use filter in the mask etc. I thought that you had to use oil-free compression equipment or to do a scrupulous job of removal of oil and organic vapours etc. at source, plus pre-cleaning of the piping so that point of use apparatus needed no filters, but that may only be for systems that are engineered for single users.
I see no reason that FRP pipe could't be properly precleaned of particulates including glass fibres, but it would take a long time for enough styrene to out-gas to a level where it was no longer detectable. The same would definitely be true for PVC or any other solvent-cemented product, but would not be true for a thermally welded material like HDPE. If the compressor is running continuously and venting the air through all the branches of the distribution system continuously, then the accumulation of solvent/monomer vapours would not be a concern. If the unit is shut down and only operated when required, the pipe would be full of styrene or other monomers for the first (considerable) while due to out-gassing.
RE: GRP Piping For Breathing Air
I'm not telling you what to do, just suggesting what some accepted practice may be in some areas, offering an example of the extremes that might be legally required, urging you to check your local laws and regulations (if there are any) and lastly, not blindly accept some vendor's advice (is he the engineer or you?), before you decide to do whatever ou think is the "right thing". Nothing more and nothing less. I never try to make the horse drink the water, unless that horse is working for me.
http://virtualpipeline.spaces.msn.com
"We can't solve problems by using the same kind of thinking we used when we created them." -Albert Einstein
RE: GRP Piping For Breathing Air
Steve Jones
Materials & Corrosion Engineer
http://www.pdo.co.om/pdoweb/
RE: GRP Piping For Breathing Air
http://virtualpipeline.spaces.msn.com
"We can't solve problems by using the same kind of thinking we used when we created them." -Albert Einstein
RE: GRP Piping For Breathing Air
Steve Jones
Materials & Corrosion Engineer
http://www.pdo.co.om/pdoweb/