21. Working in machinery spaces
21.1. General provisions
21.1.1. All operations in machinery spaces should be performed by a competent
person under the supervision of a responsible officer or senior rating.1
21.1.2. The regulations of the competent authority on the guarding of every
dangerous part of a vessel's machinery should apply (see also Chapter 13).
21.1.3. Reference should be made to Chapter 5 concerning protective equipment.
Particular attention should be paid to protecting seafarers from the effects of noise.2
Spaces in which hearing protection needs to be worn should be indicated by warning
21.1.4. No work other than routine duties should be undertaken except on the
orders of a responsible engineering officer. Maintenance work should be carried out in
compliance with manufacturer's instruction manuals. When necessary, specific work
should be carried out within the "permit-to-work" system (see Chapter 4).
21.1.5. Moving parts of machinery should be provided with permanent guards or
other safety devices such as railings or fencing.
21.1.6. If the use of any piece of machinery or equipment is considered to be
temporarily unsafe, it should be immobilized or put in a safe place or condition
immediately and, if necessary, a warning notice should be posted adjacent to or at the
21.1.7. No guard, fencing or shielding should be removed for repair or
maintenance except when the machinery to which it relates has been stopped. The
machinery should not be restarted until the fencing or shielding has been replaced and
21.1.8. All valves, pipes and fittings should be adequately supported and fixed or
clamped to avoid vibration and possible fracture. All such fixtures and supports should be
properly maintained and replaced after maintenance.
21.1.9. All items such as steam pipes, exhaust pipes and fittings which, because of
their location and operating temperature present a hazard, should be adequately lagged or
1 At a minimum, in accordance with the STCW Regulations, Chapter III or any subsequent
revision. Reference should be made to sections 20-25 of the IMO/ILO Document for Guidance.
2 See also the Guarding of Machinery Convention, 1963 (No. 119), and the Working Environment
(Air Pollution, Noise and Vibration) Convention, 1977 (No. 148). Further guidance may be obtained
from the ILO Code of Practice on Protection of Workers against Noise and Vibration in the Working
Environment (Geneva, 1984).