« Le détecteur du Dr Brucer est la simplicité même, et il repose sur l’érosion d’une charge électrique statique par rayonnement. Si vous frottez un peigne en plastique dans vos cheveux, il accumulera suffisamment de charge pour ramasser un petit morceau de papier, et sous un rayonnement de fond normal, la charge diminuera de sorte qu’il laissera tomber le morceau de papier après environ 15 secondes. Une fois que le champ atteindra environ 10 roentgens par heure, la charge du peigne sera nulle et le papier tombera immédiatement. (...) puisque la limite d’exposition est de 100 roentgens (un sievert), ceci indique qu’il reste neuf heures pour trouver un meilleur abri. »
Probably The Simplest Radiation Detector You Already Own | Hackaday
▻https://hackaday.com/2022/09/26/probably-the-simplest-radiation-detector-you-already-own
Over the years we’ve featured quite a few radiatioactivity detectors, which usually include a Geiger-Muller tube, or perhaps a large-area photodiode. But in the event of radiation exposure from a nuclear attack, how does the man in the street gauge the exposure without owning a dedicated instrument? This was a question of note at the height of the Cold War, and it’s one that [Dr. Marshall Brucer] answered in a 1962 paper entitled “When Do You Leave A Fallout Shelter“. The full paper is behind a paywall but the part we’re interested in is on the freely available first page.
Dr. Brucer‘s detector is simplicity itself, and it relies on the erosion of a static electric charge by radiation. Should you rub a plastic comb in your hair it will accumulate enough charge to pick up a small piece of paper, and under normal background radiation the charge will ebb away such that it will drop the piece of paper after about 15 seconds. His calculation is that once the field reaches around 10 roentgens per hour it will be enough to erase the charge and drop the paper immediately. There’s a comtemporary newspaper report (Page 7, just to the left of the large advertisment) which tells the reader that since the exposure limit is 100 roentgens (one sievert), this test failing indicates that they have nine hours to create a better shelter. For obvious reasons we can’t test this at the Hackaday bench, but those of us who remember the days when such topics were a real concern will be searching for a handy comb anyway.