I have been asked, "Isn't nitrogen flammable?" NO, it is not ... it is what is called an "inert"
gas, as is oxygen. However, unlike nitrogen (N2), oxygen is also an "oxidizing agent", a substance that has the ability to oxidize other substances. Between the moisture content of oxygen, and its oxidizing properties, oxygen propagates corrosion inside tires, affecting rims and valve stems. And, fact is, 78% of the air we breathe is nitrogen. Therefore, when we "air" tires, doesn't 78% of that air also contain nitrogen? Yes, it does.

Why is it, then, that a viable tire [having no leaks] can lose its tire pressure? Here's the science part .... Oxygen molecules are smaller than nitrogen molecules. That 22% oxygen, in air, is what you're losing out of your tire, as you see them go down. It is believed that not only does the oxygen seep out around rims and valve stems, but also actually permeates through the rubber tire itself.

Nitrogen is safe to use, safe to transport ─ just as propane bottles are: you know, the ones we buy for backyard grills and recreational vehicles. What makes any of these tanks hazardous is that, once filled, they contain COMPRESSED GAS ─ gas under pressure. These cylinder tanks, regardless of their size, are filled to approx. 2000 PSI (lbs. per square inch). Tires are inflated to 32-55 PSI, on average, depending on your tire size. Reducing this 2000+ PSI to 90 PSI (for inflation) is the purpose of a regulator.

Handling the tanks

This compressed gas (whether oxygen, propane, nitrogen, or helium) is what deserves respect. The contents of the cylinder tanks are under extreme pressure. If this gas wasn't compressed, we wouldn't get so much of it into one tank, and the tank would not expel it. Just remember this ─ learn, and always utilize, safe habits when moving or using any gas cylinder tank!

The valve on top of the cylinder is where the gas is allowed to exit. If you open the valve on that tank, the contents are going to escape. Most likely, though, you don't want that gas "escaping", since you just paid for it ... so, you "cap it off" by using a regulator. The regulator is the key to releasing gas contents SLOWLY and safely. The outlet gauge on the regulator registers for you the rate at which gas is "escaping" the cylinder tank, for your use.

Using the tanks

When I was ready to inflate my own tires with nitrogen, I rented a 55" cylinder tank from my local CarQuest, which contained +/- 200 cu.ft. of nitrogen. I rented it, because I knew I'd never need another tank that size again. Once my 31 tires were aired with nitrogen, all I needed was a top-off tank ─ in cases of blowouts, nails (tire repairs), or to increase my 10-ply's to 80 lbs., when pulling my travel trailer. Remember! I live where NO business offers nitrogen inflation for tires, including tire shops. It will need to be "on hand", in my garage. 

At 117 lbs. in weight, this 200 cu ft tank was very heavy. Once my dealer had loaded it into my pickup (onto a push cart I'd brought), I strapped it to the spine of the cart, and added tie-down to the pickup bed.

This way, the cylinder rides steady while the pickup is moving. It was also laying down, since I have a topper cap on the pickup bed. I decided, for ease of use at home, I wanted to leave the cylinder lying in the back of the pickup. That way (for instance), to nitrogen-inflate my boat-trailer tires, I could drive the pickup over to the boat storage, and inflate there. So I called AirGas, a nationwide company, to ask if my cylinder was safe delivering gas while lying on its side. They told me, "yes, it's only acetylene that must be in an upright position."

Here is a photo of my cylinder tank once I'd brought it home. You will note that it is not only strapped to the cart, but also the cart is tied down to the side of the pickup bed.

TIP To keep my air hose "unkinked", and in good working condition while stored, I bought a plastic reel for a garden hose (you can find them in about any lawn & garden center). After I air tires, this reel makes it so easy to coil the air hose back onto it from my tailgate.  It's ready for use the next time!

Obviously, you may not own the number of tires we do ─ maybe you need nitrogen inflation to just 4 or 8 tires. Below is a photo of the 40-cu.ft. cylinder tank I purchased to keep in the garage. The tank and regulator simply await me to "air" (oops!) nitrogen my tires, as needed ─ but these can be used for small inflation jobs, including bicycles, ATVs, my push cart and wheelbarrow. Your requirements might be covered with a 20-22 cu.ft. cylinder tank. Also, you could check into purchasing a viable used tank someone has for sale, and then have it filled with nitrogen, as needed.

There are so many ways to do it ... depending on your requirements. We sell kits with 10 ft., 25 ft., and 50 ft. air hose. That's the only difference between them. For commercial, the long 50-ft. hose supplied on the nitrogen regulator makes inflating customer tires so easy.