at the university

problème de transmission de données

Un Gamma-scout de comparaison indique plutôt 0.12 µSv/h.

mauvaise position GPS

Cette mesure correspond est une mesure d'une source radioactive

précision

Bonjour, il s'agit d'une mesure faite sut un "caillou" récupéré dans le massif central. Cette mesure a été faite dans le cadre d'un sage de 3ème pour démontrer à des élèves l'ensemble de la chaîne depuis l'utilisation du capteur jusqu'à la remontée de la mesure.

Mesure réalisée pour évaluer la réactivité du capteur en présence d'une source de radioactivité naturelle (pechblende)

Cette mesure est effectivement anormale et non representative du niveau radiologique ambient naturel dans la mesure où elle est faite avec une source test.

C'est une mesure réalisée prés d'une source naturelle

C'est une mesure d'une source

Measurement inside what is probably the most radioactive house in the world, with up to 150 microSieverts per hour measured inside the kitchen (at standing head level) and up to 50 microSieverts per hour in the bedroom (at bed level). The counter was checked and properly calibrated. This house was built with local cement rich in carbonate radium deposited by hot water in the local riverlets in the city of Ramsar. To our knowledge, this is the most radioactive house in the world. It had sheltered 3 successive generations of the same family when we made the measurement, by the same family since over 30 years (all were still alive and healthy, eating self-grown fruits and vegetables from their own garden - also radioactive). The owner of the house (the grandfather) had constructed the house from his own hands and was also the director of the most radioactive primary school in the world, located in the same city of Ramsar (built with the same radium-rich cement). See : https://www.tandfonline.com/doi/abs/10.1080/10256016.2013.821986

Dear AEPN, I think that you should be careful about this measurement for several reasons.

1) You are using the Gamma Scout with all rays (switch wide open to right on the photo). It means that the counter integrates both alpha and beta to the gamma rays. So then the µSv/h is quite a non-sense (as for example alphas are not making irradiant dose). Especially if you are measuring radium-contaminated environement, as A LOT of nucleus in decay chain are mostly beta/alpha emitters.

2) The Gamma Scout's tube (ZP1401) is not energy-compensated, and calibrated only on Cs137. It means that any event at GM tube will be considered as a 662keV gamma particle, even if it was a 53keV gamma or a 3MeV alpha (switch right-open). So it can strongly overestimate dose rate.

3) Gamma Scout is known to give a bit erratic dose rate above 50µSv/h.

So, indeed, yes your measurement shows a contaminated environement, far more than normal background, but you can't trust the µSv/h dose rate displayed on Gamma Scout.

A good measurement would, at most, measure only Gamma rays (switch to center position) to remove strong noise given from the mica window and, at least, be done at one meter above the ground and from the walls. Otherwise you are performing a surface-contamination measurement, not in µSv/h.

Regarding energy-compensation, it could be mayve more relevant to get CPS or CPS instead of µSv/h.

Best regards,

This value is very high. Are you sure you are using the right unit (i.e. micro Sv/h instead of nano Sv/h)? The quality of the photo is not good enough to see the unit. Have you the possibility to repeat this measurement?

Dear Raton, yes the measurement is correct, and there is no mistake with the units, this is probably the most radioactive house in the world. It was built with cement rich in radium deposited by hot water in the local riverlets in Ramsar