DIN EN ISO 16890-4:2023-12
一般通风用空气过滤器-第4部分：确定最小分数测试效率的调节方法（ISO 16890-4:2022）；德文版 EN ISO 16890-4:2022
Air filters for general ventilation - Part 4: Conditioning method to determine the minimum fractional test efficiency (ISO 16890-4:2022); German version EN ISO 16890-4:2022