FD ISO/TR 14644-21, X44-101-21 (01/2024)

This document addresses the physical limitations of the placement of probes and particle counters, and the tubing that connects them, particularly when providing representative samples when particles of 5 micrometers or larger are considered. . The document further defines key factors in sampling performance during classification and monitoring, as well as best practices for determining and maintaining an acceptable trade-off between counting accuracy and feasibility in real-world situations. This document includes a decision tree to identify key elements to consider when sampling airborne particulate matter and to determine whether the system requires further evaluation. Examples are also provided to illustrate the difficulties posed by typical applications and show how this decision tree can be used. This document is presumed to be read in conjunction with ISO 14644-1 and ISO 14644-2. This document is not a manual, but an explanatory document. It does not describe the measurement methods, which are covered in ISO 14644-1 and ISO 14644-2, but provides information to help effectively choose the sampling configuration, when evaluating a new system or an existing system.
(Automatic translation from French)