Acid rain is caused when high sulphur fossil fuels are burnt.

"Australian coal is low in sulphur but some coal extracted from Europe and North America is not," CSIRO exploration and mining nuclear physicist, Mihai Borsaru said.

"Armed with data from the probe, companies will be able to leave high sulphur coals in the ground."

Scientists expect that the portable borehole logging instrument, one of CSIRO's SIROLOG suite of products, will be used to measure sulphur in mine waste rock and in coal.

"Sulphur is the bane of the mining industry. High concentrations in waste rock, cause acid mine drainage. The sulphur oxidises and combines with water to form sulphuric acid, which, in high volumes, wreaks havoc on the environment."

Borsaru told the Industrial Radioisotopes And Radiation Measurement Applications conference in Bologna, Italy the probe would optimise the management of waste rock.

"It will provide mining companies with accurate sulphur readings in boreholes."