1 The Maritime Safety Committee, at its eighty-fourth
session (7 to 16 May 2008), considered information submitted by the
United Kingdom (MSC 84/23/2) on issues affecting night-time lookout.
These issues were highlighted in a recent marine accident report and
related to the time required to adapt to darkness and to the wearing
of glasses with photochromic lenses.
2 In this context, the Committee recalled that section A-VIII/2, part 3-1, paragraph
19, of the STCW Code states:
“The relieving officer shall ensure that the members of
the relieving watch are fully capable of performing their duties,
particularly as regards their adjustment to night vision. Relieving
officers shall not take over the watch until their vision is fully
adjusted to the light conditions”,
and agreed that
a suitable period for dark adaptation was typically 10 to 15 minutes,
which needed to be taken into account in determining the watchkeeping
arrangements on a ship.
3 The Committee noted that on some large vessels,
crew with lookout duties, alternate periods on the bridge with periods
of safety checks and fire watches in other parts of the vessel, some
of which will be brightly lit. On fishing vessels, the deck lights
may be very bright, and crew may come off the deck to take a watch.
The same period of dark adaptation will be required every time the
lookout returns to the bridge. Furthermore, it was important that
darkness was maintained on the bridge – making full use of blackout
procedures, ensuring that radars and console lights were dimmed appropriately
and avoiding contamination from residual light and surrounding uncurtained
areas.
4 The Committee also noted that photochromic lenses,
which darken automatically with exposure to strong light and lighten
when in dark surroundings, could reduce night vision significantly,
even in their most translucent state. Accordingly, the Committee agreed
that they should not be worn for lookout duties at night.
5 In this context, the Committee, further noted
that Guidance on blackout requirements on the navigating bridge and
the wearing of photochromic lens is included in the fourth edition
of the ICS Bridge Procedures Guide.
6 Member Governments and international organizations
in consultative status are invited to bring the above information
to the attention of ship operators, masters, skippers, officers and
ratings undertaking lookout duties.