In the section "Radiation Related Quantities" the table's row for the quantity Fluence (Φ) seems inappropriate, due to imprecision and inaccuracy. Fluence in physics is a flow during time, but in medicine it's a flow through an area. Becquerels of radiation are more relevant to medicine, but in that field the measurement is "more properly referred to as radiant exposure". Radiant exposure in photometry is visible light, which becquerels of radiation usually are not; the radiometric metric is more appropriate. So the precise "fluence" of radiation that's measured in becquerels is "radiant exposure", not the ambiguous "fluence". Radiant exposure is symbolized by H_e, indicating joules per square meter (J/m²). The table instead gives reciprocal area (cm^-2 or m^-2), which is radiometry's concern, but missing the energy component.

So I propose changing that row to instead document Quantity: radiometric exposure; Name: radiant exposure; Symbol: H_e; Unit: joule per square meter. That rendering is consistent with the radiant exposure article's table of SI radiometry units. However, since it's a derived quantity and unit rather than one with a proper name, I haven't found a year in which it was introduced, so I'd leave that blank.

Any reason not to make this change?

Note: I proposed this change in the Talk page of the Becquerel article 15:37, 18 February 2014 (UTC) DocRuby (talk) 02:03, 17 July 2017 (UTC)Reply[reply]

The problem is that the ICRU uses fluence as particles per unit area. Whilst of value in the metrological calculations used to define radiation intensity, it is a whole subject of its own within the very narrow world of ionising radiation metrology, and therefore I have removed fluence from the table as it is confusing for the reader who just wants to know about quantities that are in public/general use. Dougsim (talk)