3.2　Ensured Functions

3.2.1　PAS shall be able to release real-time speech broadcast and one microphone with the highest priority shall be available.

3.2.2　In the case that multiple signal sources are being broadcast to the same zone，the signal with higher priority shall be able to override the signal with lower priority automatically.

3.2.3　In addition to the requirements stipulated in article 3.2.1 of this code，the ENFs of business announcement system shall also be in accordance with those specified in Table 3.2.3.

Table 3.2.3　Other ENFs of business announcement system

3.2.4　In addition to the requirements stipulated in article 3.2.1 of this code，the ENFs of background broadcast system shall also be in accordance with those specified in Table 3.2.4.

Table 3.2.4　Other ENFs of background broadcast system

3.2.5　In addition to the requirements stipulated in article 3.2.1 of this code，the ENFs of emergency broadcast system shall also be accordance with the following requirements.

1　As to a PAS serving multiple purposes，emergency broadcast shall be with the highest priority.In case of being triggered manually or automatically，PAS shall be able to broadcast alarm signals（including alarm sirens），alarm voice files or real-time command voice to the relevant zone（s）within 10s.

2　Based on the environmental noise on site，the SNR of emergency broadcast shall be no less than 12dB.

3　Emergency broadcast system equipment shall be in DFS state or be with the functions of scheduled self-test and automatic fault warning.

4　Emergency broadcast system shall be equipped with a standby power supply.The switching time between the primary power supply and standby power supply shall not be more than 1s.The standby power supply shall be able to sustain emergency broadcast for over 20min.If battery is used as the standby power supply，the system shall be equipped with automatic recharging device.

5　The volume of emergency broadcast shall be able to reach the level no less than the ENSPL automatically.

6　In the case that it is necessary to release emergency broadcast manually，one touch ready shall be available.

7　The failure of one power amplifier shall not lead to the failure of the whole broadcast system.

8　The failure of one loudspeaker shall not lead to the failure of the whole broadcast zone.

9　Other ENFs of emergency broadcast system shall be in accordance with those specified in Table 3.2.5.

Table 3.2.5　Other ENFs of emergency broadcast system