Gas-tightness of the bulkhead and approval of the bilge pumping arrangement
In several schedules of Appendix 1 is written:
- “The bulkheads between the cargo spaces and the engine-room shall be gastight and shall be inspected and approved by the Administration”; and/or
- “Bulkhead between the cargo spaces and the engine-room shall be gastight”; and/or
- “Prior to loading, the bulkhead to the engine-room shall be inspected and approved by the competent authority as gastight and the safety of the bilge pumping arrangements shall be approved by the competent authority”; and/or
- “Prior to loading, the bulkhead to the engine-room shall be inspected and approved by the competent authority as gastight. Satisfaction with the safety of the bilge pumping arrangements shall be approved by the competent authority”.
This inspection and approval shall be carried out by the ships RO, on behalf of the NSI.
The individual schedules in the IMSBC Code do not further substantiate the way in which the inspection and approval of gas-tightness of the concerned bulkhead and the bilge pumping arrangements are to be conducted, nor the interval of inspection and approval. In that respect also the wording ‘prior to loading’ does not give full clarity on which particular moment in time the inspection and approval are to be conducted, as it is not worded as ‘prior to each loading’. Therefore, the NSI concludes the following:
The inspection of:
- the bulkheads between cargo spaces and the engine-room (gas-tightness); and
- the bilge pumping arrangements for a satisfactory level of safety (testing),
shall be conducted:
- during the construction of a new ship or a major conversion of an existing ship as part of the Cargo Ship Safety Construction (CSSC) Certificate; and
- as part of the annual, periodic, intermediate and renewal surveys.
These inspections includes:
-
a physical testing:
In practice the regular procedures are followed and no additional tests are required.
-
a check on the Safety Management System (SMS):
The safety management system of the ship, as required by the ISM Code, shall include procedures ensuring that:
- the quantitative measurements of hydrogen, phosphine, arsine, silane, ammonia and acetylene are being taken, relevant to the cargo;
- the concentration of these gases in the cargo spaces carrying these cargoes are being measured regularly during the voyage and the results of the measurements shall be recorded and kept on board; and
- continuous mechanical ventilation is being conducted during the voyage for the cargo spaces carrying these cargoes (where applicable: under the additional instruction / advice as per IMSBC Appendix 1 schedule).
Only after a satisfactory outcome of the inspections the gastight bulkheads and safe bilge pumping arrangements shall, subsequently, be approved by the RO.
Exemption regarding a fixed gas fire-extinguishing system
Notwithstanding MSC.1/Circ.1395/Rev.4, as amended , and with regard to individual schedules requiring, as a precautional provision, the cargo to be carried in cargo spaces fitted with a fixed gas fire extinguishing system, when the planned interval between the commencement of loading and the completion of discharge of this cargo exceeds 5 days, the NSI may exempt the ship to be fitted with a fixed gas fire-extinguishing system in the cargo spaces, provided that:
- the planned voyage does not exceed 5 days from commencement of loading to the completion of discharge of that cargo; and
- the RO submits a well-founded proposal for approval to the NSI for review and approval by the NSI.