BRITISH STANDARD BS EN 50131 2 4 2008 Alarm systems — Intrusion and hold up systems — Part 2 4 Requirements for combined passive infrared and microwave detectors ICS 13 310 ��������� � ���� ����������[.]
BRITISH STANDARD Alarm systems — Intrusion and hold-up systems — Part 2-4: Requirements for combined passive infrared and microwave detectors ICS 13.310 12&23