The Triangle of Life is a controversial theory about how to survive a major earthquake, typically promoted via viral emails.
The theory advocated methods of protection very different from the mainstream advice of "drop, cover, and hold on" method widely supported by reputable agencies. [1][2][3][4][5][6] In particular, the method's developer and key proponent, Doug Copp, recommends that at the onset of a major earthquake, building occupants should seek shelter near solid items that will provide a protective space, a void or space that could prevent injury or permit survival in the event of a major structural failure, a "pancake collapse", and specifiably advises against sheltering under tables.
Officials of many agencies have found themselves forced to respond to these viral emails spreading the "Triangle of Life" method. [7][8][9]
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According to Copp's theory, when buildings collapse, the weight of the ceilings falling upon the objects or furniture inside tends to crush them, but the height of the object that remains acts as a kind of roof beam over the space or void next to it, which will tend to end up with a sloping roof over it. Copp terms this space for survival as the triangle of life. The larger and stronger the object, the less it will compact; the less it compacts, the larger the void next to it will be. Such triangles are the most common shape to be found in a collapsed building.
According to United States Geological Survey, the Triangle of Life is a misguided idea about the best location a person should try to occupy during an earthquake.[10] Critics have argued that it is actually very difficult to know where these triangles will be formed, as objects (including large, heavy objects) often move around during earthquakes. It is also argued that this movement means that lying beside heavy objects is very dangerous.[11] Statistical studies of earthquake deaths show most injuries/deaths occur due to falling objects, not structures. Also, given that there are no warnings for earthquakes, you are more likely to be injured trying to move during an earthquake rather than immediately seeking a safe space by furniture, or near an interior wall (The American Red Cross no longer recommends doorways, as they are often not structural [12]). This strategy, combined with good engineering and educated search and rescue teams is the safest. The Triangle of Life theory encourages individuals to put themselves at far higher risk by seeking safe zones which they are unlikely to reach. However, they also state that different architectural standards in first world vs. third world countries mean that the best strategy for earthquake survival could be different: "The Red Cross is not saying that identifying potential voids is wrong or inappropriate. What we are saying is that "Drop, Cover, and Hold On!" is NOT wrong -- in the United States. The American Red Cross, being a U.S.-based organization, does not extend its recommendations to apply in other countries. What works here may not work elsewhere Mahdavifar et al. (2010) analyzed and compared both methods in detail, considering their application, the extent of people who are under the coverage, simplicity in transferring concepts, and the probability of reducing casualties and damage in developing countries such as Iran. It argued that "Duck, Cover and Hold on" was useful advice for people who experience smaller earthquakes without total building collapse, which is the vast majority of earthquake survivors. It found that the "Triangle of life" could be a better strategy during larger earthquakes in buildings with a skeleton (wood or concrete) during a building collapse, but acknowledged the possible problems of large objects shifting and crushing the person from horizontal movement, and the triangle method is also difficult to teach and communicate. Neither strategy was useful for the majority of the population in rural Iran because of the mud-brick architecture which has no structure. Based on the simplicity of teaching and the fact that 12000 times more people are affected by smaller earthquakes and injured, they concluded that duck and cover is still regarded as a better option for people during an earthquake. [13]
In 1996, Copp claims to have made a film to prove this methodology and to have recreated a model school and home, filling them with 20 mannequins. However Marla Petal, a critic of Copp, has stated that this was a rescue exercise rather than an experiment as claimed by Copp, and because it did not simulate the lateral movement of earthquakes, the results are highly misleading.[11]
The buildings were collapsed by earthmoving equipment that knocked the supporting pillars out. Half the mannequins were in 'duck and cover' positions and the others in what Copp calls the 'triangle of life' positions. When Copp and his crew re-entered the building after the blast, they calculated that there would have been no survivors amongst the mannequins in 'duck and cover' positions, as against 100% survival for those hiding in the triangles beside solid objects. Copp is categorical about the importance of this technique, saying "Everyone who simply ducks and covers when buildings collapse is crushed to death - every time without exception."[14] Petal disputes this on the exercise did not simulate the lateral motion of an earthquake, but instead they induced a pancake collapse which is rare in developed countries.[11] However these collapses can occur in areas of extremely poor construction.[11]