May we have your attention for the following presentation about safety on board

You all have heard at least one these standard safety briefings. They contain however at least two important points that can save your life once.

The first is about not inflating your life jacket before leaving the aircraft. You probably noticed how bloddy long the boarding can be, so imagine what a de-boarding of scared passengenrs can be. Add to that a thick and impractical inflated jacket, and you understand why. The only possible exception to this rule is when the plane is already filled up with water.

To be certified, any airliner must fulfill an evacuation test, consisting in evacuating the total number of passengers via half of the emergency exits within 90 seconds. Sounds crazy ? Recently, an AirFrance Airbus 340 did crash in Toronto, in a survivable way, but caught fire on one side, so they were exactly in the 50% of exits available. And they made it in time. I was quite surprised, because certification always takes place with trained pseudo-passengers, in a relaxed mood.

The other important point in the safety briefing is to put your own oxygen mask first in case of depressurization. This is really a life saver. In case of sudden depressurization at cruise altitude, your lungs won't have enough air pressure to continue transferring oxygen in your blood, hence the masks. The issue is that you have approximately 18 seconds before being so dizzy that you become helpless to anybody or yourself.

Given the noise, sudden drop in temperature and potential fog within the cabin, 18 seconds is not so long to find and put your mask in place. You can then help anyone else, but if you start by helping someone, there are strong chances than you will be incapacited before achieving anything.

One more remark, which is really common sense. Keep your seatbelt fastend after landing until the engines are off and the sign is switched off. First, you won't save any time buckling off early, or may be half a second. But if the pilot has to brake sudenly, you could have a close and unpleasant encounter with the seat in front of you. Beleive me or not, but dozen of people have broken arms, or strong neck injuries yearly because of that... How silly is that ?

To close this post, a sample of safety announcement. The text is the original united one, but the picture...