ISO 19702:2024

OVERVIEW

This document specifies requirements and makes recommendations for sampling systems for use in small-scale and large-scale fire tests, for the selection of parameters and use of the FTIR instrument, and for the collection and use of calibration spectra.

The primary purpose of the methods outlined in this document is to measure the concentrations of chemical species in fire effluents which can be used to:

a)       provide data for use in combustion toxicity assessment without requiring biological studies;

b)       allow the calculation of yield data in fire characterization studies;

c)        provide data for use in mathematical modelling of hazard to life from the fire effluent by characterizing the effluent composition generated by physical fire models;

d)       characterize the effluent composition of small-scale physical models and larger-scale fires for comparative purposes;

e)       assist in the validation of numerical fire models;

f)         set the conditions for exposure in biological studies if required;

g)       monitor biological studies where used; and

h)       assist in the interpretation of biological studies where used.

This document specifies principles of sampling and methods for the individual analysis, in fire effluents, of airborne volume fractions of carbon monoxide (CO), carbon dioxide (CO₂), hydrogen cyanide (HCN), hydrogen chloride (HCl), hydrogen bromide (HBr), nitric oxide (NO), nitrogen dioxide (NO₂) and acrolein (CH₂CHCHO).

NOTE            Depending on the optical path length, there can potentially be some saturation of certain spectral lines at high concentration, leading to incorrect volume fractions.

In most common cases, a wide concentration range can be measured by an FTIR instrument. Typically, it is in the range of a few µl/l to thousands of µl/l for HCl, HBr, HF, SO₂, NO_x, and HCN, and up to a few per cent for CO, CO₂ and H₂O. These mentioned species are only indicative, and many other species could be added.^[27] Although not specifically defined in this document, as they were not specifically studied in the SAFIR project,^[18

COMMENTS

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