Frequently Ask Questions

Not currently. Neutrons are too high of an energy and too fast for standard GM tubes to detect. Neutrons need to be slowed down in order to detect them using a (BF3) boron trifluoride (uses a neutron to alpha particle conversion to get a measurement)or a High Pressure Helium 3 probe (uses a neutron to positron conversion to get a measurement).

The Digilert detects alpha down to 2.5 MeV

The dwell time (upper right of the screen.) is set to a longer value than the Meter Response time next to the analog needle. The settings are 60 seconds for the dwell time and 1 second for the meter. A quick spurt of five counts would make the needle jump to higher since it is integrated over a brief amount of time. The dwell time would, in this case, integrate over a longer period of time and thus smooth out these statistical variations.

The Japanese standards are based on the Critical Detection limits (50% confidence level) and are able to be reasonably achieved based on a 600 sec background sampling time. The Standard MDA limits (95% confidence level) need the longer 900 sec time to achieve reasonable results.