Lesson 8: Avalanche air blast

Did I get it right from lecture 8.1 (around 9:45) that an air blast, that is some kind of a pressure shock wave, caused by a fast moving avalanche can potentially rupture lungs?

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I’m glad someone else was perplexed by this. I figured the rush of air was the equivalent of very high atmospheric pressure, but I wondered if it had to be inhaled, or if it would be involuntarily inhaled. It’s a horrible thought either way!

and there is another link embedded there too:

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The embedded video in the first article is amazing! Thanks @DavidHik!

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Thanks @DavidHik, that video and article are great. It’s amazing to see what it is like inside an airblast, and I guess this was a relatively mild one. I don’t think I would have stayed as calm as those guys and kept on filming but I am glad they did!

The guys in the vid seemed fine, but I was terrified! The rainbow was a nice touch too.
Thank you, David, for posting these.

Wow. In that video, I also kept thinking “get out of there!!!” Too close to the Japanese tsunami and other cases where people thought they were far enough away… as a species we seem inclined to underestimate the power of physical laws at large scale.

Hi @jirim - I posted this somewhere else in the Study Group first, but not being sure how to cross-reference things on this platform, I’ll just post again below! David

The technical term is ‘barotrauma’ - which is an injury caused by a pressure change. It can damage ears, sinuses, teeth, lungs, stomach, intestines - anywhere in your body where there is a sinus or cavity with air.

Here is a link to the US CDC guide: https://www.cdc.gov/masstrauma/preparedness/primer.pdf

The human body can survive relatively high blast overpressure without experiencing barotrauma. A 5 psi blast overpressure will rupture eardrums in about 1% of subjects, and a 45 psi overpressure will cause eardrum rupture in about 99% of all subjects. The threshold for lung damage occurs at about 15 psi blast overpressure. A 35-45 psi overpressure may cause 1% fatalities, and 55 to 65 psi overpressure may cause 99% fatalities

Typical Injuries Sustained in Barotrauma Typical Injuries Sustained in Barotrauma - RCEMLearning India

It can happen underwater too:

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I’m curious as to how common barotrauma is with avalanches. Barotrauma is more a rupture of the lungs than the more dramatically sounding exploding lungs. I know it is fairly common with those who experience bomb blasts, but I have been unable to find anything about in relation to avalanches. I understand that in theory it could happen, but are there any reported cases of it happening?

Articles on the causes of death and injury in avalanches, such as here and here do not mention it. This article on avalanche injuries also has no mention of it, but I did find this interesting:
‘General body compression by the snow has been reported to cause respiratory failure and death in avalanche victims. The firm generalized pressure exerted by the avalanche debris may also cause significant chest trauma in a few avalanche victims. However, in the vast majority of victims, rib and sternum fractures appear to have been caused by external cardiac massage during the resuscitation efforts. The remarkably high incidence of resuscitation-associated thoracic injuries may be explained by hypothermia-induced stiffness of the thorax.’

The chapter of The Oxford American Handbook of Disaster Medicine on avalanches also has no mention of this.

Not avalanche related, but here are two unfortunate stories of people whose lungs did seem to explode. Time and Taiwan

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