The inlet gas connection is the point at which the installation pipework begins.
Where cylinders are stowed in cylinder lockers or housings the inlet gas
connection must be situated inside the locker or housing, as this will help
prevent damage to it leading to a leak inside your boat. The inlet gas
connection must also be securely fixed to help prevent damage and must be
readily accessible so that it can be inspected for security and checked for leaks.

If there are holes in the cylinder locker this could allow leaked gas to escape
into the boat and if this gas is ignited it could then explode or start a fire. To
ensure this doesn't happen, installation pipework from cylinder lockers must
either be from a bulkhead fitting or above the level of the cylinder, low pressure
regulator and associated equipment. [7.11]