IRSST - Institut de recherche Robert-Sauvé en santé et en sécurité du travail

Fiber Count


With this method, fibres in the air can be counted with a phase contrast optical microscope by applying the NIOSH 7400 method. It allows for the measurement of different fibres such as asbestos and any other fibres for which the refractive index is compatible with the mounting solution (e.g., artificial vitreous mineral fibres, natural mineral fibres, etc.). The sampling device used in this method is a filtering membrane inserted into a cartridge. The method has been updated to adapt it to the new regulations that come into force on October 28, 2022, which entail a change in the definition of respirable asbestos fibre and an adjustment of the reference values.


Additional Information

Collection: Laboratory methods
Category: Analytical method
Technical Authority:
Online since: October 27, 2022
Format: Text