SHIP ТО SHIP TRANSFER GUIDE (PETROLEUM)
(Third Edition 1997)
For Use with Crude
Oil and Petroleum Products
Chapter 3
Safety
3.1 GENERAL SAFETY
For all STS transfer operations each master remains at all times responsible for the safety of his own ship, its crew, cargo and equipment and should not permit safety to be prejudiced by the actions of others. Each master should ensure that the procedures recommended by this guide are followed and, in addition, that internationally accepted safety standards are maintained. In this regard, the most prominent international safety manual in use for cargo handling advice is the International Safety Guide for Oil Tankers and Terminals (ISGOTT).
The overall safety of any STS transfer operation
depends on the type and condition of the equipment in use and strict adherence
to well documented safe procedures.
3.2 SAFETY DRILLS
Despite careful attention to safety procedures,
emergencies can occur. Often such events can be contained and their effects minimised by preparing ships' crews, through a system of
drills, to deal with a variety of emergencies. An appropriate drill should be held, where
practicable, within 24 hours and in any
case, not more than seven days preceding an STS transfer operation. STS safety drills should be a regular feature of
shipboard emergency drills.
3.3 CHECK LISTS
Check lists (presented in chronological order) for STS
transfer operations will be found in the appendices to this guide. The check lists should assist organisers
and masters to adhere to relevant safety procedures. The check lists should be
used, not only at the time of transfer, but also when organisers
are planning an operation (Check List 1). Adherence to check list procedures will ensure that
the most important aspects of an operation are covered.
Check lists are essential reminders of the principal
safety factors to be considered. They should be supplemented by continuous vigilance
throughout the whole operation.
Before mooring operations commence, each ship should
confirm with the other that all items on Check List 2 and 3 have been checked
and found to be correct.
3.4 ACTION IN CASE OF INFRINGEMENT OF SAFETY
If either ship fails to observe any of the safety
requirements during the STS transfer operation, this should be brought to the
attention of the master of the ship concerned and operations should be
suspended until the situation is rectified.
3.5 SAFETY DURING CARGO TRANSFER
The basic safety requirements for a transfer operation
are similar to those for a normal port cargo operation as contained in the
latest edition of ISGOTT, particularly Appendix A
(Part A). For convenience, the relevant check list from ISGOTT
is reproduced in Appendix 2. The
following points are emphasised for an STS transfer
operation:
3.5.1 Smoking and Naked Lights
Regulations regarding smoking and the use of naked
lights should be strictly enforced. Warning notices should be displayed and smoking rooms
should be designated and clearly marked.
3.5.2 Earths on Electrical Switchboards
Earth indicator lights showing on the main switchboard
indicate a faulty circuit and such faults should be immediately traced and
isolated. This is to avoid the risk of arcing, especially in
deck areas where hazardous accumulations of gas may be present.
3.5.3 Boilers and Diesel Engines
On ships fitted with boilers, precautions such as
soot-blowing should be carried out prior to commencing the approach manoeuvre in order to avoid hot ash falling onto a ship's
deck during the cargo transfer.
The combustion characteristics ofdiesel
engines should be closely monitored. In case of sparking from the funnel,
transfer operations should be stopped immediately.
3.5.4 Ship to Ship Electric Currents
3.5.4.1 The Elimination of Electrical Current and
Electrostatic Charge in Cargo Hoses
In order to eliminate the potential for incendive arcing between the two ships when presenting the
hose string for connection:
• a single insulating flange should be fitted within each hose string (or at one ship's manifold); or
• one length of electrically discontinuous hose should be fitted in each hose string; or
• hoses that are specially constructed to prevent static build up or electrical currents transferring between ships, should be used.
3.5.4.2 Other Places Where Electrical Arcing May
Occur
All ship-to-ship mooring lines should be insulated either by using the natural properties of soft mooring lines or by attaching a soft rope tail to the eye of each steel wire mooring line. If using soft rope tails, they should be of suitable length so that they extend to the outboard side of the ship receiving the mooring.
Care should be taken to avoid low resistance ship to
ship electrical contact in the following areas:
• non-insulated metallic ladders or gangways between the ships - by the fitting of rubber ends;
• derrick or crane wire runners and hooks - by careful operation;
• unprotected bare wires and chains within fender support nets or cages - by good quality maintenance.
3.5.5 The Use of Radio and Satellite Communication
Equipment
Transmissions from a ship's main radio station can cause electrical resonance in insulated parts of some ship fittings such as mast stays and this can cause arcing across deck fittings. Similar arcing can occur on ship's wireless aerials especially over the surface of insulators when they have a coating of salt, dirt or water.
The use of a ship's main radio equipment during cargo
operations can be dangerous. Radio transmissions should not be permitted during
periods when there is the possibility of flammable gas in the region of the
antennae or where there is doubt about the effective earthing
of stays, derrick equipment and other such fittings.
The main radio transmitting aerials on both ships
should be earthed (grounded) and neither ship should use this equipment while
alongside one another. Satellite communications equipment can be used for communications, however, the risks described below should be
taken into account.
Satellite communications equipment normally operates at 1.6 GHz and the power levels generated are considered to present few ignition hazards. However, this equipment should not be used when flammable gas is in the vicinity of antennae.
VHF and UHF communications are of low energy and
therefore do not produce the same potential dangers as might be expected from a
ship's main radio transmitter. Accordingly, such communication may be used,
even while ships are together, and may also be an alternative to the ship's
main radio equipment when within range of a suitable coast station.
Any hand-held VHF and UHF radios, as used for mooring
and cargo operations, should be of intrinsically safe manufacture.
It should be noted that portable cellular telephones,
pagers, cameras using batteries, etc., can constitute a risk to the vessels if
used in a hazardous area.
Precautions should be taken to ensure that all
personnel involved in the transfer, especially those who may be visiting the
vessels on other business, technicians, surveyors, etc., are made fully aware
of the dangers and any restrictions in the use of such items.
3.5.6 Radar Usage
3.5.6.1 General
The use of radar involves the operation of electrical
equipment which is not intrinsically safe. Depending on the relative size of the two ships,
during cargo transfer operations, the radar beam of one ship may at times sweep
the cargo deck of the other and be close enough to create potentially hazardous
power densities in areas where flammable gas mixtures could be present. Consultation between masters is advisable before a radar is used during cargo transfer operations. The following section gives further advice.
3.5.6.2 The Use of 3
cm and 10 cm Radar
Radiation from radar operating at frequencies above 9000 mHz (3 cm) may be considered safe at distances of
over 10 metres.
The radiated power from such radar should not present
an ignition hazard provided scanners are correctly sited above the
superstructure. Radar operating in the
3 cm waveband will normally be safe but should only be used with
discretion.
At the lower frequencies, as used by 10 cm radar, the possibility of induced arcing
in parts of a ship's structure is present at ranges of up to 50 metres. As a consequence, 10
cm radar should not be used when there is a possibility that a scanner may
point directly at or near the cargo deck of the other ship.
3.5.7 Gas Accumulation
An STS transfer operation should be suspended if cargo
vapour accumulation around the decks or manifolds of
either ship constitutes a risk to the vessels or personnel and should not be
resumed until it is considered safe to do so. It is worth noting that air carrying flammable or
toxic vapours flowing past superstructures can result
in eddies, or build up of gas on the lee side of the structure. These concentrations may find their way into machinery
spaces or accommodation blocks.
3.5.8 Electrical Storms
When an electrical storm is present or imminent in the
transfer area, the cargo transfer operation should be suspended and all vent
risers, cargo systems and IGS systems secured until such time as it is
considered safe to resume operations.
3.5.9 Galley Stoves
Before permitting the use of galley stoves and other
cooking appliances while a vessel is engaged in STS operations, the ship's
master and the STS superintendent (if applicable) must, after taking into
consideration the location, construction and ventilation of the galley, jointly
agree that no danger exists. Oil or gas fired stoves or electrical appliances using
exposed elements should not be used.
3.5.10 Readiness
of Fire Fighting Equipment
Firefighting equipment should be ready for immediate
use on both ships. Foam monitors on each ship should be pointed towards
the cargo manifold in use and left in a suitable condition for hands-off
operation. Additional foam firefighting equipment should be
immediately available for use on deck.
3.5.11
Accommodation Openings
All access doors to the accommodation should normally
be kept closed during cargo transfer operations. The master of each ship should designate those access
doors that are to be used for personnel transit. Where possible, only doors remote from the main deck
cargo area should be used. All doors opened for personnel transit should be
closed immediately after use.
The air conditioning system for the accommodation
should be switched to the re-circulation mode.
3.5.12 Unauthorised Craft
No unauthorised craft should
be allowed alongside either ship throughout the transfer.
3.6 SAFE WATCHKEEPING
STS transfer operations can put additional demands on ships' crews. It has to be remembered that not only are personnel required for cargo transfer operations but also to keep a safe navigational or anchor watch (see 6.2.3).
Each master should take into consideration the estimated duration of operations to ensure that safe and fatigue-free watchkeeping can be maintained throughout (Reference 7). Due regard should also he taken of Section 7.4 where additional manning for the deck watch is recommended during cargo transfer operations.
For the reasons described in this section, transfer operations taking place simultaneously from either side of a ship (STBL) are generally not recommended.
Masters should ensure that sufficient crew members are
available for the intended operations. An adequate number of crew will be required on both
ships for mooring operations, for hose handling and for derrick or crane
control.
3.7 HELICOPTER OPERATIONS
Helicopter operations should not be permitted while
vessels are moored together without the prior approval of the organisers, both ships' masters, and STS superintendent. If approved, the person with overall
advisory control will co-ordinate the operations locally.
No helicopter operations are to be carried out during
transfer of cargo and/or bunkers and/or ballasting into cargo tanks.
Helicopter operations should be co-ordinated well in advance between the vessels, organisers, agents, and helicopter operator.
Both ships are to carry out all helicopter operations
in full compliance with the ICS Guide to Helicopter/Ship Operations.
All helicopters used should be equipped with marine
band VHF communications capability.