Safety and Emergency Actions
A pump that is "stopped" is not a pump that is "isolated" — that difference is where people get hurt.
Key Principles at a Glance 5 points
- Remove the pump from auto start and priority before anyone touches it — auto-start and remote start are how pumps kill people during maintenance.
- Never rely on a closed valve: prove zero pressure at the purge cock before opening any casing.
- Running dry destroys mechanical seals, gland packing and wear rings, and can seize a screw or gear pump. Never repeatedly restart "to see if it picks up".
- A mechanical seal is not adjustable — if it leaks, reduce duty and plan replacement; do not keep tightening anything.
- Ear protection is required at or above 90 dB(A); at 85 dB(A) or less there is no limit on exposure time.
1. The Hazards of Pump Work
| Hazard | Where it arises | Control |
|---|---|---|
| Stored pressure | Any pump, casing, or line not proven depressurised | Purge cock, vent, drain. Never rely on a closed valve. |
| Electrical | Motor, starter, local panel, auto-start | Isolation permit, lock and tag, remove from auto and priority, prove dead |
| Hot surfaces and hot liquid | Feed pumps, hot oil, steam-driven reciprocating pumps | Cool down, correct PPE, drain safely |
| Rotating machinery | Coupling, shaft, flywheel | Guard in place, isolate before working, no loose clothing |
| Chemical / oil contact | Fuel oil, cargo, chemicals, treated water | PPE, MSDS, washing facilities |
| Confined space | Pump rooms (cargo), tank entry | Enclosed space permit, atmosphere test, standby man |
| Flammable atmosphere | Cargo pump rooms, fuel oil spaces, tank entry | Gas test, no ignition sources, ventilation, permit |
| Manual handling | Motor removal, casing covers, impellers | Chain block, correct lifting points, two-man rule |
| Noise | Machinery space generally | Ear protection where levels reach or exceed 90 dB(A) |
Noise — the numbers worth knowing
Noise damage is based on sound level and time of exposure.
| Level | Safe unprotected exposure |
|---|---|
| 120 dB(A) | 30 seconds (the acceptable maximum daily dose) |
| 110 dB(A) | 5 minutes |
| 100 dB(A) | 50 minutes per day |
| 90 dB(A) | 8 hours per day (the ideal limit for manned machinery spaces) |
| 87 dB(A) | 16 hours |
| 85 dB(A) or less | No limit on exposure time |
Ear protection is necessary and a suitable warning should be posted at the entrance to any space in which noise levels reach or exceed 90 dB(A). Many available ear muffs and plugs are not adequate — the performance of approved types should be checked against measured noise levels.
2. Safe Isolation — the Mandatory Sequence
Run the standby pump and stop the pump to be worked on.
Control room circuit breaker off.
Electrical isolation permit obtained; local panel breaker off.
Lock and tag.
Shut the suction valve.
Shut the discharge valve (high-pressure discharge especially).
Check via purge cock that there is no pressure inside the pump.
Remove the pump from auto start and from priority.
Display the 'men at work' warning board.
Drain and dispose of the liquid correctly.
Cool down before opening hot pumps.
Atmosphere test and permit where the pump room or space is a confined or flammable-atmosphere space.
3. Emergency Actions — Pump-Specific
Loss of suction / pump running dry
Immediate action:
- Stop the pump. Running dry destroys mechanical seals, gland packing, wear rings and can seize a screw or gear pump.
- Investigate the cause — level, strainer, suction valve, air ingress, priming system.
- Do not repeatedly restart to "see if it picks up" — each attempt damages the seal faces further.
- Restore prime properly before restarting.
Do not run a magnetic drive or canned motor pump dry under any circumstances — both cannot run dry and cannot resist extended cavitation.
Cavitation / severe noise and vibration
Immediate action:
- Reduce flow by throttling the discharge, or reduce speed — this can stop rough running and avoid damage.
- Identify whether the cause is temperature, level, suction restriction, or speed.
- Correct the root cause before returning to full duty.
- If damage is suspected, plan an inspection at the next opportunity.
Pump or motor overheating
Immediate action:
- Stop the pump if the temperature is rising rapidly or there is any smell of burning.
- Check lubrication, cooling, flow rate, and gland adjustment.
- Check for low-flow operation — at low capacities the power supplied to the pump is no longer useful work and becomes heat.
- Do not restart until the cause is identified.
Bearing failure / seizure
Immediate action:
- Stop the pump; isolate.
- Do not attempt to restart — a seized bearing can shear the shaft or destroy the casing.
- On strip-down, examine the failure mode (lubrication? alignment? contamination?) before renewing.
Gland or seal failure with leakage
Immediate action:
- Packed gland leaking heavily: adjust the gland to restore drop-by-drop leakage. If it will not adjust, the packing is exhausted (stage 3/4) and must be renewed at the next opportunity.
- Mechanical seal leaking: reduce to minimum duty and plan replacement. Do not keep tightening anything — a mechanical seal is not adjustable.
- If leakage is of a hazardous liquid or into an occupied space, stop the pump and isolate.
- Where an auxiliary packing arrangement is fitted, install the backup packing only after a seal failure has occurred — it receives no lubrication while the seal is healthy.
Fire involving a pump or pump room
Immediate action:
Stop the pump and isolate its electrical supply.
Close the suction and discharge valves if safe to do so — this removes the fuel source.
Raise the alarm; notify the bridge and Chief Engineer.
Fight the fire with the appropriate medium for the fuel involved.
Do not enter a pump room where a flammable atmosphere may exist, or after a fire, without atmosphere testing and a permit.
After the event, do not restart until the cause is identified and the pump, motor and wiring have been inspected.
Loss of a pump during a critical operation
Plan for it before it happens:
| Critical pump | Failure consequence | Prepared mitigation |
|---|---|---|
| Boiler feed pump | Boiler low water → boiler shutdown | Standby feed pump proven; automatic changeover tested |
| Sea water circulating pump | Condenser vacuum loss → main engine power reduction | Standby pump; scoop injection where fitted |
| Main engine LO pump | Main engine damage within seconds | Standby pump on auto; engine protection tested |
| Fuel oil booster | Burner flame failure → loss of power | Standby booster; automatic changeover |
| Steering gear hydraulic pump | Loss of steering | Second pump; emergency steering procedures; drills |
| Emergency fire pump | Loss of firefighting capability | Monthly test runs; priming system proven; fuel (3 h reserve for diesel drive) |
4. Safety Rules That Are Absolute
Never defeat a pump trip, bridge a safety interlock, or isolate a protective device except under an approved test or repair procedure.
Never start a positive displacement pump against a closed discharge — the relief valve is the only thing between the pump and destruction.
Never throttle a pump's suction to control flow.
Never run a pump dry — least of all a magnetic drive or canned motor pump.
Never leave a pump in auto start while anyone is working on it.
Never open a pump casing until pressure is proven zero at the purge cock.
Never assume a closed valve is holding — prove it.
Never remove a guard and leave the pump available for start.
Never re-use a joint or O-ring where the maker specifies renewal.
Never sign off an overhaul without recording the measurements and the post-overhaul test.
5. Environmental and Regulatory Obligations
- Bilge discharge overboard only when: on passage, at least 12 nautical miles from land, not in a Special Area, with an approved oily water separator or filtering system in operation, and with a working oil content meter, alarm and automatic stop.
- In Special Areas (Mediterranean, Baltic, Black Sea, Red Sea, Persian Gulf), discharge is permitted only when the separator or filtering system achieves the required low oil content.
- Record every overboard discharge in the Oil Record Book with the required detail — date, position, quantity, oil content, and the equipment in use.
- Never introduce detergents or emulsifiers into bilge water feeding a coalescing-type oily water separator.
- Cargo and ballast circuits must be isolated from each other and from bilge and fuel circuits, using blanks, lock-up valves or interlocks.
- Report any pollution incident immediately through the ship's reporting procedure.
The ship's SMS, permit-to-work system, maker's manual, and Chief Engineer's orders always override these notes.