To many a new cave/wreck diver, nothing says “I’m with the big boys” as much as a dive helmet does. Mind what you get and how you use it though.
Cave/wreck diving helmets are primarily for mounting lights to. You shouldn’t need it for impact-protection because (outside of exploration-diving) things likely won’t be falling on your head underwater (also, do not rely on a cave helmet to allow you to drive your DPV into the cave wall).
Note that commercially-available diving helmets only offer limited to no impact protection. Manufacturers are very clear about this.
Also note that if your dive will take you through dry sections of a cave then that is obviously a factor that might change some of the aforementioned.
Mounting your light
Do not mount your primary light to your helmet permanently:
- Having the light follow your each and every slightest head-movement is not as much fun as it sounds
- You want to be able to point the light in directions without pointing your head there
- Conversely, you want to be able to point your head in directions without pointing your light there (most importantly when you turn to face your dive buddy)
Mainly, you want to be able to temporarily mount your primary light onto your helmet while you’re doing things that require both hands. For example handling spools and tie-offs. Outside of those situations, the light-head should be in or on your hand.
Consider using a way of mounting that will allow you to point your light downward if you have to momentarily look at your dive buddy.
Which helmets
Buy it yourself:
In the realm of cave diving, by far the most popular commercially-available helmet is the Light Monkey helmet.
It’s a reiteration of the kayaking helmet that was popular among cave divers in earlier days because of its low-profile and lack of padding. Note that LightMonkey has since cranked up the price quite a bit on what is essentially just a piece of molded plastic. If you buy this product, consider taking out the inner suspension straps.
Do it yourself:
If you’re more frugal and/or DIY-inclined, you can quite easily make your own. Some pointers:
- Start with a helmet that is not meant for diving (bicycle or skating helmets will do)
- You’ll probably want to take out the padding (it usually consists of copious amounts of positively-buoyant material)
- Because you’re taking out the padding, go for a size that is way too small with padding and as such will be just right without the padding (you’ll probably be looking at kids’ sized)
Andy Davis has an excellent walkthrough on making your own helmet for under $20 up on his site. There’s also a great video from InnerSpace Explorers up on YouTube with interesting approaches (like replacing the helmet’s padding with neutrally-buoyant liner).