I see the stated aim of Radioactive@Home is to detect gamma radiation. I would like to know why alpha and beta radiation are not measured? Is this a limitation due to the cost of suitable equipment, or are these forms of radiation not considered to be as significant?

I found a similar project called Safecast in Japan which mentions this in their faq?

Alpha and Beta are lower energy, and can be blocked with a sheet of paper or thick clothing. Alpha and beta pose a greater risk if they are inhaled or ingested. The Cs137 that was released by Fukushima Daiichi is primarily a beta emitter which is why food contamination is such a concern.

Only gammas are able to easily penetrate the housing of a discharge tube to generate a countable event inside it. Alphas and betas, even having similar energies, may not be detected with such a tube, as they simply are stopped before reaching the gas inside.

Hi exsafs, thanks for your reply it makes sense to me. I suppose if the detectors were mobile or predominately outdoors (think safecast) then the detection of these other forms of radiation would become more important/practical.