Statutory Alert: Secondary means of venting on tankers – SOLAS amendments Applicability: Designers, builders, owners and operators of tankers
Changes to SOLAS Regulations II-2/4.5.3 (Cargo Tank Venting) and II-2/11.6 (Protection of Cargo Tank Structure against Pressure or Vacuum in Tankers)* will apply to tankers constructed on or after 1 January, 2017.
The changes mean that these ships must have an independent, secondary means of venting for each tank: that is, a full flow pressure/vacuum (P/V) valve or a pressure sensor that provides an alarm on detecting over-pressure or under-pressure.
Note: a pressure sensor is only acceptable as a secondary means if a full flow P/V valve is fitted as the primary means of venting for each cargo tank, as per the arrangement in SOLAS Regulation II-2/18.104.22.168.
These changes have been made to protect tanks in the event of a mechanical failure or inadvertent closure of the isolating valves or devices on the inert gas main/vent branch pipework.