Lifejackets affect every seafarer worldwide, whether or not they use them on a daily basis, they are aware of their existence as a basic and arguably essential piece of equipment. Most of which will be designed to increase a person’s visibility as well as keeping them afloat, whether that is by fitting a light, using reflective tape or simply being a bright colour.
When fitted, Lifejacket Lights, can be self-activating and have a minimum light intensity and burn-time based on recommendations and requirements of their approving organisation.
It is widely accepted that lifejackets alone save lives, the Maritime and Coastguard Agency (MCA) for example - using Her Majesty’s Coastguard and Marine Accident Investigation Board (MAIB) figures - recorded 146 maritime fatalities in UK waters in 2013. The MCA’s Casualty Review Panel analysed 25 fatalities where the victims could have worn lifejackets and concluded that it was ‘probable’ 14 of those would have survived if they were wearing a lifejacket.
Lifejackets thereby assist the problem of fatigue for persons overboard, however locating the casualty is an additional complication – especially as a human is mostly submerged in the water, visibility is a cogent issue when it comes to increasing chances of survival at sea.
Are lifejacket lights enough to save lives?
A representative case from the MAIB involved fishing vessel ‘Zenith’ on 29th January 2012. The vessel was 29 miles southeast of Kilkeel, Ireland when a fisherman fell overboard while hauling nets at around 1400. Despite the crew and skipper’s swift actions to manoeuvre the vessel back alongside the casualty, they were unable to retrieve him from the water in the moderate sea state. He was then lost. Dublin Maritime Rescue Co-ordination Centre (MRCC) coordinated a search involving a coastguard helicopter, two Royal National Lifeboat Institution (RNLI) lifeboats and nine fishing vessels, they continued the search until night faded around 1715, and resumed in the daylight hours over the following 3 days.
If the fisherman was wearing a lifejacket, with the aid of a light-signalling device, the search may have continued into the night of the first day, as despite the water being only 8°C, there was a possibility he could have been alive.
Throughout examination of past MAIB reports, there is a clear reoccurrence of incidents involving mariners being lost at sea, which could have been avoided if they were wearing a lifejacket – the visibility of them at sea can then be increased by use of lights to reduce any search and rescue time – particularly important in colder waters.
What has been done so far?
The original International Convention on the Safety of Life At Sea (SOLAS) 1974 convention states nothing with regards to lights being fitted on lifejackets – it does however mention lifebuoy self-igniting lights in Chapter III, Regulation 21(f), giving a performance requirement of a luminosity intensity of 2 Candela Units (cd) and a minimum burn time of 45 minutes.
However, a requirement for visibility of persons wearing life jackets was apparent in Chapter III, Regulation 22(c)vi, indicating lifejackets should be of a ‘highly visible colour’.
It was not until 1st July 1998 there was revised Chapter III of SOLAS to bring into force the Life-Saving Appliances (LSA) Code; this was adopted by the Maritime Safety Committee (MSC) in MSC.48(66) to give specific requirements for all life saving appliances onboard.
Then, a further revision, through MSC.81(70) adopted on 11 December 1998 makes, brings the requirements for lifejacket lights as they are today:
Must be of white colour
The luminosity intensity must be >0.75 cd in all directions of the upper hemisphere, without the use of a lens
Burn time must be a minimum of 8 hours
A flashing light is to be between 50 and 70 flashes per minute
What technology is available?
There are three types of lights used in lifejacket lights, namely, the incandescent bulb, a Light Emitting Diode (LED) or a Stroboscopic Lamp.
Due to the size and low-power consumption, most SOLAS approved lifejacket lights in 2016 are LED lights - with technological advances in recent years, an LED light can convert as much as 70% of electrical energy into light, compared to incandescent bulbs converting only around 15%.
Is it time for a change?
The LSA code's revision of Chapter III come into force in December 1998 - almost 18 years ago - 2 years before Sony released the Playstation 2 and at the same time the MP3 player was invented. Not to mention our home PCs were running Windows 98...
No one could argue that any form of light attached to a lifejacket will aid Search and Rescue Operations, but how effective is a light approved to the minimum specifications SOLAS provides?
In 2016, we have the technology available through better batteries (forced to improve by the greater complexity of our personal devices) and brighter, more visible lights to be fitted as a standard to lifejackets worldwide.
Currently through the University of Plymouth, I am conducting a study into the effectiveness of lifejacket lights available in 2016, compared to a light which meets only the minimum SOLAS requirements of 0.75cd.
Through a series of experiments I am to test whether there is a significant difference between a person's perception of lights; based on their brightness, colour and whether they are flashing or steady - using unmodified LED, incandescent bulb and stroboscopic type lifejacket lights.
I will then measure the effectiveness of each sample light using an opinion-based questionnaire answered by a number of participants.
I will also test the technology in laboratory conditions to determine the full capabilities of the lights and batteries.
From this, I aim to answer whether lifejacket lights are just an additional feature offering more peace-of-mind opposed to increased chance of survival, or if a further revision of SOLAS regulations is required to match the capable criteria of current technology.