Standard UNE 81753-2:2024 describes the procedure to be followed and the equipment needed to determine the airborne concentration in the workplace of:hydrogen chloride gas and hydrochloric acid mist, hydrogen bromide gas and hydrobromic acid mist, nitric acid vapours and mist, in the retention element, undiluted.
The measurement procedure described in this standard can be used to take:
- Measurements to determine the concentration of workplace exposure
- Measurements for comparing with the limit values of professional exposure in order to assess inhalation exposure and periodic measurements (UNE-EN 689 and UNE-EN 482).
- Measurements of the initial evaluation of the time-weighted average concentration and of the variation in the concentration in space (UNE-EN 482).
This method distinguishes between anions from gases and acid mist and their particulate salts, which could be present simultaneously in the workplace. The particulate salts of acids, if present, can be captured in a prefilter.
The air concentration range is determined based on the sample volume. The lower limit of the application interval depends on factors such as: detector noise level, sample and reagent blanks, extraction efficiency and interference in the chromatographic analysis.
This document is supplemented by the standard UNE 81753-1 for the simultaneous determination of non-volatile inorganic acids.