BSI 20/30381924 DC:2020 Edition

The method described here has the purpose of quantifying the absolute exposure to mineral oil vapours and droplets, within a concentration range from 0.5 mg/m³ to 125 mg/m³, in the inhalable fraction of the workplace air. This method has been validated in accordance with the provisions of EN 13936 and ISO 20581 and has an expanded measurement uncertainty in the region of 20% – 30% within the measurement range stated.

The GGP (Gesamtstaub-Gas-Probenahme) sampling system enables both droplets and vapours to be collected but any other personal sampler capable of collecting the inhalable droplets and vapours simultenously can be used. A glass fibre filter is used to collect the droplets. A downstream sampling tube containing polymer resin is used to collect the vapours and more volatile components in the mineral oil. The GGP system cannot be used for distinction between exposure to gases and droplets, since droplets collected during sampling may vaporize from the filter and collect on the polymer resin.

Following extraction, the samples are analysed by Fourier transform infrared spectroscopy (FTIR) in the wavenumber range from 3000 cm^-1 to 2800 cm^-1. This method is not specific for mineral oil, since it detects all substances with C-H bonds collected on the sampler.

The method described in ISO 23506 is based upon the “MAK Collection for Occupational Health and Safety 2016, Vol 1, No 1”, “Cooling lubricants and other complex hydrocarbon mixtures, immiscible with water – droplets and vapours”(2).

ISO 23506 contains comprehensive information and instructions on the equipment and chemicals to be used.

This method is applicable for water soluble oils and metal working fluids.