Part 7 – Backup Lights
In the last ‘Wreck Head’ I started my discussion on primary lights with a little story about God’s primary light, the sun. Of course it has a cycle that it goes through and after around 12 or so hours in our sky it goes down. We are then plunged into darkness and before house and street lighting we all walked around banging into things and each other. Some of us fell down big holes or walked into bear caves and were eaten alive!!!
No, No, No… what utter rubbish. God in his infinite wisdom designed his own backup light so that we could all be safe while he put the sun on a trickle charger overnight. His backup light is the moon of course. Which funny enough is not made of cheese as previously theorised.
It does not take a rocket scientist (no pun intended) to work out why a backup light system would be a good thing to carry on all penetration dives. Loss of lighting in overhead environments has, unfortunately, been the cause of the untimely demise of a fair few divers. The really sad thing is it’s so easy to setup a backup system. What we want is a backup system that is pretty dependable and easy to use. And divers can’t even blame cost on not having lights anymore as the manufacturers have released backup lights to suit all pockets without jeopardising safety.
In this ‘Wreck Head’ we have a look at the design, reasoning behind, and the placement of backup light systems for overhead environment diving.
The most important thing I want from my backup light is… well, light!
Now this sounds daft but look at The Big Guy for example, he made loads of backup lights for us, they are called stars, but you can hardly bask in their light can you? So when I pick a light I want it to project a decent amount of light. I do not need it to be as powerful as my primary light in any way shape or form. I just need to be able to see my guideline, my directional markers, potential entanglement, abrasion hazards and of course the exit which is of paramount importance.
With this in mind, it means we can downscale the size of the backup light. We do not need anything complex and it does not need to be the size of a Winnebago. By downscaling we get pros and cons. The pros are, we can stow the light really easily. Therefore it can be placed in an area where it is super streamlined, easily accessible and easily restowed. The cons are that unless you place it properly it can be a pain to find and if the light is not set up or placed properly it can be easily dropped and lost. Of course the final issue is that small lights have shorter burn times… or do they?
Modern backup light systems use LED (Light-Emitting Diode) bulbs that emit a huge amount while using a relatively low amount of power. LED lights also have an extremely long life with the average LED lasting around ten to twenty thousand hours. In today’s world, buying a backup light that is not LED is quite simply nuts. Hell, do any of the manufacturers make non LED lights?
The ideal backup light needs to be a thin long(ish) cylindrically shaped light with no handle on it. I prefer to have no switches either; I like lights that are turned on by screwing the light head in or out. The problem with having a light with a switch on is that sometimes switches don’t work. However, modern switches are much more reliable than they were just a few years ago.
I like the long cylindrical shape as I can fix a single piston clip to the base of the light and have the light hang from my Chest D Ring on my harness. The light needs to be around the same diameter as the width of a piece of webbing. This allows us to secure the light to the webbing using bungee loops or preferably bicycle inner tubing threaded onto the harness. The light must not be too long as it will hang too far towards the diver’s waist making it very uncomfortable to wear. Also, if it is too long, accessing the light will be a lot more difficult.
So, we hit the wreck with our primary, umbilical, lightsaber, monster of a light that will make those things at Wembley look like Christmas tree lights and a backup. Sorry, big mistake. We take two backup lights with us. Backup lights need to be trustworthy and reliable so the industry standard is to use non-rechargeable batteries rather than rechargeables.
The simplicity is that rechargeable batteries lose their charge quite quickly and sometimes don’t take on charge properly. Sometimes the batteries just die. With non-rechargeable batteries we open a new packet of factory made, one life only batteries, this minimises the chances of any of the above failures. But just to be double sure, we have a second light prepared in exactly the same manner. So if backup light one goes, we simply move to light two.
This also gives us a time advantage, as it should take an age to burn two lights out. The second light can also be given to a teammate in the event they have a VERY bad day out and lose all their lighting. My favourite reason for carrying that third light is that it can be tied into the guideline in the event of a lost buddy scenario. The small light ties easily into the line and the search diver can leave the beam of the light facing the exit in case the missing diver returns to the line. What a bloody brilliant bit of lateral thinking by the person that designed this technique.
Using the backup light is really simple. Both lights are piston clipped to the chest D rings on the left and right sides of the harness. If one has to be used, the diver simply pulls the light free from the bungees or tubing, turns it on and aims it in the direction they want to go. NEVER unclip the light from the D ring – if you drop the light, it stays attached to the D ring and most importantly, YOU! Another great advantage of setting your backup light system like this is that if you have to work with both hands, you can let the light go and it will naturally shine down illuminating whatever you are working with.
And there you have it.
I hope you agree with me now that not carrying a backup light system is quite frankly mad! Simple, cheap, streamlined and easy to use. And let’s face it, they look über cool too!!!
Paul is the Director of Training at RAID. To find out more about the courses that RAID offers, visit www.diveraid.com.