How much current is fatal?
The electrical equipment on board a ship is subjected to a lot more harsh treatment than they would ever see on shore which could lead to their deterioration and hence possible danger for the crew.
Voltage seemingly as low as 110 V can prove fatal; if the associated current is of the order of 0.1 Amps. Since power = voltage * current this means that a power of mere 11 watts can prove deadly hence the need to be insulated as we will see below.
Marine electrical safety is a very elaborate topic having several aspects to cover, so we will talk about some very basic tips here and continue the discussion in our future articles.
Marine Electrical Safety Tips
- Make sure all electrical cables are physically inspected for any cuts, abrasions or if they are immersed in water due to clogging etc. The same should be notified and appropriate measures should be taken to rectify or report the fault so that it can be repaired in dry-docks.
- If any sparks are noticed, be sure not to ignore them. They could lead to fire which is one of the deadliest enemies of the ship. It is better to nip this enemy in the bud rather than giving it a chance to spread.
- Always use intrinsically safe equipment especially in places where the presence of spark can lead to disaster.
- Never leave the marine wiring having loose connections or joints without proper insulation. This is known as Jury rigging or Jerry rigging (wrong-spelling) in nautical terms and refers to temporary unsatisfactory repairs as these could lead to problems and losses in the long run.
- When carrying out maintenance or repair on any equipment make sure to switch off power from the main electrical panel and also make sure to put a notice near that switch which says that “work in progress – do not switch on”. This would ensure that no over-enthusiastic person would come and switch on the power without bothering to check why it was off in the first place.
- Wear proper protective gear when working with electrical machineries and follow all instructions, relevant checklists etc. Having understood the equation given in the introduction section, you will realize that since the current flowing also depends on resistance, if you provide an easy path for the current to flow by making your body wet or without much insulation, the current will be sufficiently higher than the minimum required value to harm you.
- Electrical fires on board (even on land) require special handling and therefore everyone on the ship must be aware of how to react in case of electrical fires in terms of the fire extinguishers to be used and other steps to be followed. This can be drilled into the staff by carrying out regular safety drills which train the crew for such a situation
- Extension cables should be secured properly without any knots of unnecessary bends. If possible try to roll it up in a nice manner uniformly and store in a dry place.
These few tips will go a long way to ensure that the marine electrical systems do not turn against you to harm you but act as your faithful servants.