Document ID: chunk:federal_register_of_legislation:F2018L01173:body:0:p85
Version: federal_register_of_legislation:F2018L01173
Segment Type: other
Provision Reference: 
Character Range: 220069–222838

when the glass is under pressure. If a gauge glass or cover needs to be replaced or repaired, the gauge should be shut off and drained before the cover is removed.
The same isolating and maintenance principles should be applied to thermal oil heaters and systems as those required for boilers. However, as the venting and drainage systems are closed systems to the thermal oil header tank or thermal oil drain tank respectively, additional care must be taken when isolating heaters to ensure that the system is fully drained and no residual pressure remains, before fittings are removed or pipes disconnected.
After completing work on thermal systems, measures must be taken to prevent water and moisture being introduced to the system. The steam produced, its sudden expansion and the significantly greater volume occupied may cause damage to equipment and significant disruption to the system as a whole. Before the system is refilled from the thermal oil header tank, the header tank drain should be tested for the presence of water. This should also be done whenever the header tank is refilled from the thermal oil drain tank or thermal oil storage tank.

18.2              Propulsion machinery
The propulsion machinery must be provided and maintained in accordance with the requirements of Marine Order 12 (Construction – subdivision and stability, machinery and electrical installations) and the manufacturer's operating manuals.
Maintenance should be carried out under the supervision of an engineer officer and the officer informed immediately if any actual, or latent, fault or defect is observed with remedial action being taken as appropriate.
Where necessary, suitable staging, which is adequately secured, should be used to provide a working platform (refer to section 11).
Before any work is done, the machinery should be stopped with the throttle or starting system closed, the turning gear or a suitable brake engaged and a warning notice posted.
Before anyone is allowed to enter or work in the main engine crankcase or gear case, the engine-starting system must be in local control and fully isolated with starting air drains opened to atmosphere. Turning gear should be engaged and a warning notice posted at the start position and turning gear local control. Turning gear should be under the control of the person carrying out the work. The spaces should be well ventilated and the atmosphere tested.
Before the main engine turning gear is used, a check should be made to ensure that all seafarers are clear of the crankcase and any moving part of the main engine, and that the duty deck officer has confirmed that the propeller is clear.
If a hot bearing has been detected in a closed crankcase, the crankcase should not be opened until sufficient