This standard BS EN 15805:2021 Particulate air filters for general ventilation. Standardised dimensions is classified in these ICS categories:
91.140.30 Ventilation and air-conditioning systems
This document specifies the header frame dimensions of air filters for general ventilation to be used in air handling units, air intake system filters for rotary machinery and other applications. This includes pocket filters, rigid (V type) filters and filters to which header frame dimensions are applicable.