GB/T 39088-2020 in English

Interpretation of the core content of the standard

This standard specifies the technical requirements for the sound receiving system in fully enclosed bridge ships to ensure effective lookout is maintained through acoustic monitoring means. The main technical indicators include:

Detailed explanation of key technical requirements

4.1.2 Audio function

The system must have a noise suppression algorithm to maintain clear signal reproduction under a maximum ambient noise of 65dB(A). Typical cases show that the use of adaptive filtering technology can improve the signal-to-noise ratio by more than 15dB.

5.3 Laboratory test method

Type test requires the use of a 1/f² noise spectrum (see Figure B.2) to simulate actual sea conditions, and the test signal must contain the characteristic frequencies of typical ship sound signals specified in COLREG72. It is recommended to use a semi-anechoic chamber for 360° omnidirectional testing.

Implementation and application recommendations

Standard evolution background

This standard is derived from IMO Resolution MSC.86(70), which mainly addresses the problem of reduced natural acoustic lookout capability caused by fully enclosed bridges. Compared with the 2002 version of IEC 60945, new key requirements such as direction identification persistence (≥3s) and whistle suppression function have been added.