DIN CEN/TS 17153:2018-11

The equation for correcting the airflow, which depends on the ambient conditions, is incorrect in some standards published by CEN/TC 156. CEN/TS 17153 gives guidelines to correct the measured air flow rate when measuring conditions are different from standard conditions. This document gives a correct equation and its derivation. It applies to a power-law formula giving the air flow rate as a function of a pressure difference with an air flow rate coefficient, C, varying with temperature and pressure. This document applies to: - passive elements of air distribution systems with a cross-section area that does not depend on pressure; and - volume flow rate (and not mass flow rate). It does not apply to fans and air terminal devices with automatically controlled openings (variable openings). The responsible German committee is Working Committee NA 041-02-51 AA "Lüftung von Wohnungen (SpA CEN/TC 156/WG 2 und CEN/TC 156/WG 16)" ("Residential ventilation (mirror committee to CEN/TC 156/WG 2 and CEN/TC 156/WG 16)") at DIN Standards Committee Heating and Ventilation Technology and their Safety (NHRS).