Disposing of used CO2 cylinders


To the editor: As inflatable PFDs have become the life jacket of choice for boaters of all stripes, we should be asking what to do with used CO2 cylinders.

Inflation is achieved by releasing pressurized CO2 gas into the bladder. Bladder size is tied to the amount of inflation desired and determines how much gas is needed. What’s left is an empty steel bottle, which must be disconnected and disposed of.

After a recent trial of the new ThrowRaft inflatable throwable device, I was left with four of these husks. I hesitated to just throw them away but, in light of recent changes in the recycling industry, I couldn’t assume my recycler would accept them. I wrote to the company and got the reply, “No problem, empty and tops removed, acceptable.”

In fact, according to Leland — a company in business making pressurized gas containers for 52 years — a million disposable CO2 cylinders are manufactured a year, and 80 percent are recycled. Seems pretty high, except 20 percent means that 200,000 cylinders are NOT recycled. Figures include large cylinders and industrial products, but consumer devices include beer kegs, bicycle tire inflators and paintball gun tanks.

A label with reordering information.

Ann Hoffner

The welded-closure cylinders used in marine applications have potentially unlimited shelf life, but attached to working PFDs they are not eternal. The steel is zinc coated to inhibit corrosion, but the coating can rub off under constant use, exposing the steel to rust. Though no standards exist in the U.S., if you are depending on an inflatable PFD for life saving, it’s a good idea to check the cylinder’s service indicator regularly and also consider changing it periodically.

To be recycled (or disposed of with regular trash, if that’s the only option) cylinders must be empty. A used cylinder has an identifiable puncture hole in the business end. If it doesn’t, the safest thing to do (probably) is insert the cylinder back into the PFD and activate it. The Internet offers instructions on puncturing cylinders using a nail, but unless done very carefully the nail or cylinder can become a projectile.

When you go to rearm the PFD, Leland suggests applying the label that hangs on a new cylinder neck to the inside of the PFD to make identification easy. There are dozens of models, but the correct one can be determined either by model number or by using a cellphone to scan the label barcode.

—Ann Hoffner and her husband, photographer Tom Bailey, spent 10 years voyaging aboard their Peterson 44, Oddly Enough.

By Ocean Navigator