Qantas flight 30 damage, photo by www.mirefoot.co.uk's, http://www.flickr.com/photos/self_catering_cottages_in_the_lake_district/sets/

Only about 40–50 rapid aircraft decompression accidents occur each year, so it’s likely you’ll never encounter one while flying, nevertheless, each of us should be prepared.

If rapid decompression occurs at a cruising altitude of 39,000 feet, for example, an average healthy adult, will have a time of useful consciousness, of 15 to 20 seconds, longer at lower altitudes. According to British aviation experts, at that altitude, without oxygen, a healthy adult would die within a couple of minutes.

That’s why, in a rapid decompression accident, passengers must quickly don their emergency oxygen masks, and pilots begin a rapid descent of their plane to a “breathable” altitude.

Last week, I wrote about the FAA requiring the airlines to disable the emergency oxygen in aircraft lavatories. So, I thought it would be beneficial to offer some useful suggestions in case you’re caught in a rapid aircraft decompression accident.

Wear the right clothing for your flight. Wear a good pair of shoes or leather sneakers, never sandals or flip-flops. For women, wearing heels may make an airborne fashion statement, but you don’t want to be wearing them in case of an emergency. Sandals or high heels make it hard to move about a debris strewn cabin.

The passengers of Qantas flight 30 who suffered through a rapid aircraft decompression know all about debris blowing around the plane, including pieces of ceiling, and how cold and windy it can get with a huge hole blown out of the side of one’s plane at 39,000 feet, with the outside air at -40ºF to -76ºF.

I always wear long pants and long sleeved shirts, made with natural fibers (synthetics or high synthetic content blends can be a fire hazard in a crash) when flying. It can help you stay warm in case of rapid decompression. I have a jacket with me when flying, to help me stay warm in case of airplane air conditioning problems, and in case of an accident. Loose or elaborate clothing can get snagged on obstacles in a plane’s tight quarters, especially if there’s some damage.

Wear your seat belt at all times while seated. If rapid aircraft decompression occurs, and when the plane begins its rapid descent, it will help prevent injury from being knocked about.

When rapid decompression occurs, your oxygen mask should drop from overhead. Put it over your mouth, slip the straps over your head, then tighten them by pulling their ends. Breathe into the mask normally. The mask’s bag might not inflate, or inflate only while you’re exhaling. If it doesn’t inflate, it doesn’t mean it’s not working.

Under current FAA rules, the emergency oxygen in aircraft lavatories is disabled.

If rapid decompression occurs while you’re in the lavatory, you will have to try to get to your seat for oxygen quickly. Most healthy adults will have about 30 seconds at maximum cruising altitude, somewhat more time at lower altitudes, to return to their seats.

Don’t wait for the flight attendants to assist you. They might be helping other passengers, having difficulty moving around due to debris, or awaiting instructions from the cockpit according to FAA procedure 3-1859.

If you remain calm, and use this strategy, you’ll likely be able to get to your seat safely from the lavatory. Pull up your pants or skirt or other clothing, and fasten them to prevent tripping. Unlatch and open the lavatory door. Remember it must be pulled in to get out. Proceed to your seat, but if you begin to feel faint and see an unoccupied seat, sit there and use its emergency oxygen mask.

If you know someone’s in the lavatory, don’t remove your mask, leave your seat, and attempt to directly help, unless your are a healthy adult, and the plane’s been descending for at least 1–2 minutes, so you won’t quickly pass out endangering yourself, which wouldn’t help the passenger in the lavatory. Immediately attempt to get a flight attendant’s attention. They have portable emergency oxygen and are equipped to offer assistance.

Always accompany your children to the lavatory, and stay next to it, while they are inside. That way you will be in position to help them, if necessary.

If traveling with children, or the elderly, put on your mask first, then help with theirs. You have a reasonable amount of time to get everyone’s mask on, seated with you, but since the “thinner” air can make you light-headed and unable to assist them, don your mask first.

On Qantas flight 30, apparently some oxygen masks didn’t deploy. If this happens it’s generally easy to pry open the access panel to free the masks. Otherwise look for empty seats, if any, and use the masks there. It’s also possible to share masks, if necessary.

Shortly after the aircraft suffers rapid decompression you’ll likely feel the plane dropping fast. This is likely a good sign the pilot is in control and quickly descending the aircraft to a “breathable” altitude.

Try to remain calm. Passengers of commercial aircraft which go through rapid decompression usually survive with no adverse long term health effects. Even with a huge hole in the side of the plane, everyone on Qantas flight 30 landed alive and safe.

As the plane descends rapidly, the loss of pressure will likely cause your ears to pop. This can be extremely uncomfortable or even painful. You can help yourself by periodically holding your nose, while keeping your mouth closed, “blow the air out of your ears.” This is an old diver’s trick.

Rapid decompression can cause mist or vapor to appear in the cabin, which looks like smoke. Don’t panic. You can tell if it’s smoke by smell.