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read the source document for the sticky post, it is only 16 pages long, one concentrated hour of reading and you would have known without asking,...

and you would have known better than just about anybody has the time to delve into on an internet blog,...

PLUS,...you would have all the good references to go after and read which are referenced in the sticky post's source document,...

in a nutshell from the reference material(s),...

*...Two very important statistical concepts, the decision level (DL; a.k.a. critical level [LC]) and the*

minimum detectable amount (MDA; a.k.a. detection level [LD], lower limit of detection [LLD], ...)

are based on the standard deviation of the net count rate when an appropriate blank is being

counted. DL and MDA are covered mathematically later. Suffice it to say at this point that one

can determine, in advance of receiving a sample, how small an amount of radioactive material is

likely to be distinguishable from background with a giving counting system and choice of counting

times: this amount is the MDA. The MDA is the value that one can legitimately advertise that one

can measure with reasonable assurance....take notes, write the hierarchy of thresholds down in a linear fashion, and illustrate for yourself which each progressive threshold of assurance is communicating,...

and then you will be able to conceptualize and remember it,...

it's not overly difficult, but you have to do the work to make it work for you,...

and it's just statistics, statistics are as good as the assumptions behind them,...

airline travel is the safest form of mass transit,...

from the assumption you are not going to die in an impact vaporized fuel cloud of fiery incineration,...

unless that happens to your airliner,...

then you're 100% dead and the assumption is 100% dead wrong,...

and there you go,...