Convert counts per second to bq per square cm?

Answer 1

(CpSx(100/swab efficiency)x(100/counter efficiency))/area sampled=Bq/cm2

I don't convert CPS to Bq/squaer meter; because it compares apples to Oranges in a bogus empty way. Bequerels are a measured count of the fragments coming from a number of atoms disintegrating in three dimensions in 1 second. Fine, but if you count only those going "UP" to get your two dimensional meters per second number ,you ignore those going "DOWN" and thus cut your total atomic disintegration (your radioactivity) rate in half. It also ignores the space above the two dimensional plane which may (and likely is) filled with flying frying fragments in that three dimensional volume of "sizzle space".

A more honest measure is per cubic meter, or per gram dirt, or per cm x square meter plus the space above it. People inhabit a three dimensional "sizzle space" and if they get hit by an atomic "flying fragment "(externally or internally) they "sizzle, depending on the amount of fragments (including Gamma photons as "fragments for now) the type of flying fragment( alpha,beta,gamma,neutron etc),the energy of the fragment,where it hit,and what they had for lunch. So data only on Bq per square meter is deceptively incomplete.