2024 SOLAS Chap. IV amendment and Revised Performance standard of Radio installation

2024 SOLAS Chap. IV amendment


The amendment enters in force on 1 January 2024 and applies to all ships including ships in service to which SOLAS Chap. IV apply.

Major points of the amendment

  • (1)  Requirements of two-way VHF radiotelephones, SART and AIS-SART in SOLAS Chap. III, Reg. 6 is transferred to SOLAS Chap. IV, Reg.7.
  • (2)  The definition of sea area A3 is changed from within the range of the Inmarsat geostationary satellite to within the range of the Recognized Mobile Satellite Service (RMSS) carried onboard.
    For the change, the navigable sea area of each ship depends on RMSS carried onboard.
  • (3)  The primary system of radio installation required for ships navigating in sea area A3 is changed to MF and RMSS.
  • (4)  No requirement for the function of radiocommunication by MF/HF NBDP.

List of radio installations for each sea area

Extract from Para 2.3 on COMSAR.1/Circ.32/Rev.2

Revised Performance standards of Radio installation

  IMO Resolution  
MSI HF NBDP MSC.507(105) MSC 507 105 (imo.org)
MSI and SAR MF(NAVTEX), HF MSC.508(105) MSC 508 105 (imo.org)
Radar SART MSC.510(105) MSC 510 105 (imo.org)
VHF MSC.511(105) MSC 511 105 (imo.org)
MF, MF/HF MSC.512(105) MSC 512 105 (imo.org)
INM-C MSC.513(105) MSC 513 105 (imo.org)
Two-way VHF MSC.515(105) MSC 515 105 (imo.org)
Aeronautical Two-way VHF MSC.516(105) MSC 516 105 (imo.org)
Integrated Communication System MSC.517(105) MSC 517 105 (imo.org)

The performance standards for VHF, MF, MF/HF, and INM-C apply to equipment installed on or after 1 January 2024. However, IMO issued MSC.1/Circ.1676 to invite Member States to consider permitting until 1 January 2028 the continued installation of VHF, MF, MF/HF and Inmarsat-C complying with the current performance standards, A.803(19), A.804(19), A.806(19) and A.807(19) as amended. Refer to MSC.1/Circ.1676 for the contents.