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Installing compressed air lines in commercial space, any guidelines?


Hot Rolled
Jun 9, 2015
I'm in a new space and I'd like to have the air lines run properly. All I know is I think some of it has to be rigid for the reason if there's a fire, it won't melt and result in fanning the flames. The rapid air stuff seems like a box check in this regard, and I don't want to use it. Where are the requirements for this? Local fire department? I know electrical stuff is NEC for the most part, but not sure what the guide is for compressed air.

I just need to run across the shop and down both walls, drops for air guns and a couple machines. What are my options? Copper I suppose? Would something like flexible tube in EMT conduit be ok? Wall to machine can be flexible? Compressor is a Polar Air (Eaton) 80 gallon.

Advice is appreciated. Thanks
A few thoughts in addition to surplusjohn's very wise suggestion to have both ends of the main line connect to the reservoir:

1. The main line tees for the drop lines should point up, with the drop lines having an inverted-U from the main line tee.

2. The drop lines should have drain valves at their bottoms, not hose connectors. The hose connectors should tee out of the drop lines a couple feet above the drain valves.

3. Quarter-turn valves, and enough of them to be able to a) isolate the halves of the main line loop, and b) the individual drop lines. Quarter-turn valves are far better drain valves than petcocks.

4. Secure the whole shootin' works to the building structure with "rubber-lined" clamps.

5. Isolate the distribution piping from the reservoir mechanically with woven-wire-mesh shielded hose, at both ends of the main line loop.
In my day job at a fortune 500 manufacturer, they use type L copper for all air lines in the plants and labs as far as I have seen.

John Garner has lots of good tips above also.
A good filter coming out of the compressor & before any air dryer if you plan to use one . Theres lots of stuff online about making your own air dryer using copper pipe , but with the price of copper these days a real airdryer may be cheaper ? What every anyone tells you that you should use PVC get as far from that conversation as you can . As mentioned above 1/4 turn valves are your friend . Get a automatic drain for your compressor tank that you can set to drain the tank during the day/nite . You can get rubber air hose with a braided stainless steel outer jacket for the line from the compressor tank to the piped system . Unless things have changed , ( which they probably haven't ) if you have employees using air your tank has to have inspection bungs , & for insurance you probably should have a permit for compressed air . I know some of this stuff you probably didn't want to hear , but it's stuff to keep in mind .
good luck
I have done a number of installations in TV stations in different states and there never was any guidance, rules or regulations, or inspection. I was more or less completely on my own.

I always used either galvanized pipe or copper tube.
I went over this quite a bit over the years and at the end of the day cost is all about the same. Copper pipe, black pipe, rapid air (AL). They all cost pretty much the same overall, with cost being similar Copper pipe would be the way to go.

No rusting, very stable, high pressures. Make sure you put lots of drains in, an air dryer wont hurt.

Good Luck.

I have some black pipe we had for 30 years and the inside is all rust and the airflow is restricted, also get rust particles breaking off and sandblasting out the end of the air gun. Not good overall.
All good answers - a few points - if you are going to use ANY steel pipe & fittings, make sure it's galvanised.

My 1st to 21st choice would be copper.

On a long drop down, if you can put a short leg with a drain of some description below the take off point.

Hydraulic hoses make great anti vibration connectors
I mean you could go stainless pipe then just get the ends threaded NPT..... might be a bit expensive though.
Ive seen welded pipe for some,
seen threaded galv pipe in 20ft sections with a 1" main
rapid air alum tubing ive seen but is $$$
I just did an install at our facility with rapid air rigid. A bit pricey but worth it without the hassle of messing with copper. Code is pretty relaxed compared to electric and gas. You best bet is look up you county and state regs for it.
+1 on the Air Dryer. If you install one, you may want to put it on an electrical timer, so that it kicks on in the morning before you turn on the compressor, and shuts off after you have left for the day.
Thanks for the advice. I do have a dryer after regulator and filter. Left to my own devices I'd just ziptie flexible down the wall and be done. However, my last place mostly burnt down due to a dope lab a few units down. It was clear the fire didn't start in my place, but I want to tighten up my shot group on this. I was hoping not to call code down at the city, but I guess I will. Youtube seems to be videos that fall into 2 categories: infomercial for atlas copco with little real details, and some joker running pex in his garage, so not much help.

I guess rapidair actually isn't too expensive for a 100ft kit in 1/2". I was planning to have a day of it with copper and learn to sweat it. Thanks for the tips. For braided stuff to the wall, can you use washing machine hook ups? I'm not sure where to look for something more appropriate. Thanks
copper pipe
durable[20years no repairs]
10 ft lengths convenient for drops
assembly line built the drops then solder in place
I used 3/4 for runs,1/2 for drops, I ran the drops at right angles and the difference in diameter is enough to keep out moisture except at end of run or unused fittings. I have also had a dryer for most of the time, current Zek dryer allows zero moisture, old northern hydraulics one was nearly perfect also.

I will never do threaded pipe again, what a PITA. I have not needed to add a drop but if I did, copper is simple,
I've worked at three manufacturing facilities. One ran all copper, fantastic compressor room with filtered/conditioned air intake and top-notch dryers - no issues.

One ran all TransAir (Parker), average compressor room/dryers - no issues.

The current (and by far the largest) is all iron with above-average compressor rooms, but not as good as they can be, with top notch dryers. Threaded for <2", clamped for >2". Again, no issues.

I think it comes down installation quality and air prep. Garbage in, garbage out.
Ok, here's some braided hose. Seems a lot more legit than washing machines hook ups:

Thanks for the advice. I'll grab some of these hoses for the supply end and some copper to go around the walls.
I used 1" raw steel pipe. With upside down "U" for the drop lines.

Then barbed brass fittings like mcmaster 91465K54 and hose like mcmaster
15 years and no issues and no leaks. Pretty much thats how my dads old machine shop was set up and that was good for 20years plus. Of coarse I am in the midwest, so YMMV.
I've done miles of air lines at many different facilities. The 2 main lines we install is copper with propress fittings and the ingersoll rand blue aluminum setup. Both are great for the use.

Besides both being corrosion resistant here are the pros and cons.

Ingersoll rand
- must buy from them or a competitor style.
- the pipe is reasonable, but the fittings can be a little crazy in price
- plastic male adapters suck as they are plastic thread. If you get females and treat them like sch 40 pvc, they are fine.
- the fittings are not the easiest to put together. You must mark them for proper fit up. I have fixed hundreds of these fittings where other companies have done it wrong.
- the fitting are in theory, infinity reusable
- the fittings are all unions so it makes it very easy to make changes later on.

- only buy L copper
- copper is either pressed or soldered fittings, so each fitting is permenant
- very common anywhere
- fast install
- press fittings are very strong, I had a 90* fitting unbend to a 45* and it still held with no leaks
- cheapest mist efficient limes for dirty water to lay in

I can tell you that no dryer will ever get all the water out. It is 100% impossible. They can get a reliable 95+% constantly though. The way to get the other 5% out is to design your runs properly. Don't have them drain back to a tank. Run your main horizontal manifold so all your branches cone off from the top. Make sure they go up at least 12". Make the horizontal run download to there far end. Put only 1 down pipe that connects directly down from the horizontal so any and all water will drain into this pipe. Then put an automatic drain or a manual drain that you will bleed every day. This works perfectly. This gets whatever humidy that condensate inside the pipe out and keeps your air dry. Do multiple drops down if you have a long run.