Scope and object
This International Standard relates to definitions, test methods
and procedures for density gauges utilizing ionizing radiation,
designed for measuring the density of liquids, gas vapours,
slurries, or fluidized solids. The output signals from density
gauges may be either analogue or digital. The measurement system
may also include multiple input signals with various means of
compensation and signal conditioning prior to the output signals.
Reference to compliance with this standard shall identify any
deviations and the reasons for such deviations.
Safety aspects are covered in other IEC and ISO standards (for
example IEC 60405, ISO 2919, ISO 7205, ISO 9978). Consideration
should also be given to compliance with all applicable national and
local regulations and codes of practice.
NOTE 1 Many density measuring systems in use today have multiple
sensors (i.e. temperature and pressure) and employ various means of
compensating the basic sensor signals to minimize the effects of
extraneous influence quantities that introduce measurement errors,
or to correct the density reading to a standard reference
temperature or pressure. Dedicated microprocessors have further
enhanced multiple input signal processing and error compensation
NOTE 2 In this standard, the term "density" means the density of
the irradiated material being measured. It is used interchangeably
to mean mass per volume or per cent solids. Radiometric sensors in
density applications generally measure mass attenuation of a photon
The object of this standard is to establish definitions,
specifications and test methods for nuclear density gauges.