Your first jump course instructor probably told you that skydivers wear helmets to protect their head in the plane and in freefall, not to protect it from impact with the ground. The first thing you should do before purchasing a helmet for skydiving is understand the above. Although anecdotal evidence seems to support the idea that wearing a helmet can reduce or eliminate the possibility of head injuries in an impact, skydiving-specific helmets are not tested to any standards or certified by any bodies.
Since you can purchase certified helmets for other sports (cycling, skateboarding, snow sports, hockey, motorcycling), why not for skydiving? And for that matter, why are non-certified skydiving helmets more expensive than certified snowboarding helmets? It comes down to economics. There are millions of snowboarders out there. A company making snowboarding helmets can reasonably expect to sell enough helmets at a low price point to more than cover the costs of testing and certification. There are not millions of skydivers out there.
Which also explains why skydiving specific helmets are more expensive than helmets for most other sports. A smaller market means that a company must make more profit on each sale to cover their costs. Most companies manufacturing helmets for skydiving were started by skydivers, often in their garage. It’s not quite like Nike deciding to break into the skydiving market – not that they would, since participation in skydiving is a drop in the bucket compared to participation in more mainstream activities.
There are a variety of helmet types built specifically for skydiving. If you are still on student status and tired of using the smelly dz student helmets, it may be worthwhile to invest $40-60 in one of your own. There are several plastic open face helmets on the market. The ProTec full cut (~$50) has been a standard in skydiving for decades. Square One makes and sells the MSX (under $40) and SkySystems produces the Benny (~$60), both of which are based on the venerable ProTec design.
All of these helmets work great for any type of recreational skydiving. They offer good peripheral vision, a reasonable level of head protection (in some cases, better than that offered by more expensive composite helmets) and places to mount audible altimeters. Even if you intend to replace it in the future with a more expensive “camera ready” or full face helmet, keeping a basic helmet on hand is a good idea for those jumps when you don’t need or want to take a camera (or that expensive helmet – water jumps, for example).
Full face or open face? For your first helmet, open face has definite advantages beyond being able to use it on your student jumps. They can be used on any type of skydive – belly fly, wingsuit, camera, water, freefly, CRW, etc.. They allow you to hear better, both in the plane and under canopy. One disadvantage is a lack of face protection when compared to a full face. This may be important to you if you intend to pursue competition relative work (belly or vertical) – but it’s not likely to matter much during your first hundred jumps or so. Another potential disadvantage to an open face is the need to wear eye protection.
Full face helmets are the choice of most belly fliers and many freefliers. Unlike open face helmets, there is no need to buy goggles. Full face helmets tend to be quieter than open face. And they do provide some protection for the face in an impact situation.
Which helmet brand is right for you can sometimes depend on the size and shape of your head. The best way to find out which helmet(s) fit your head size and shape the best is to try on as many different helmets as you possibly can. With your head measurement (soft measuring tape, mid forehead, above the ears, all the way around) and the various manufacturer’s sizing charts (yes, each one is different), you can determine which sizes to try on in which brands – or for those very, very smart folks amongst us, which helmets just aren’t gonna be big enough to ever fit..