Hi. Welcome to the forum. Good subject to study.
It's been decades since I did this sort of thing, but...
Needs to accommodate eye protection in a convenient fashion.
Small comm devices on ears aren't great - need something that covers the entire ear and won't fall off or slip when sweaty. Also has to be able to take a beating when it gets knocked against things.
[ame="http://www.amazon.com/Chainsaw-Safety-Helmet-Guard-Muffs/dp/B000IZ3V30"]Amazon.com: Chainsaw Safety Helmet and Face Guard W/ Muffs: Home Improvement[/ame]
As a general rule, anything that can be broken off will be broken off. Even when not in use the helmet will end up tossed around and/or be stowed in baggage which will be tossed around. Whatever starts off clunky will end up high speed, low drag after the users get done "fixing" it.
Batteries can and will die. Also, they add weight, which is fine IF you need lights, but if you don't then you don't wanna sling around the extra weight on the end of your neck all day.
You should visit SAR personnel, take a look at what they have now and find out what THEY think needs fixing.
EDIT: Second impression - what protects the nose from falling debris?
Last edited by dwh; 02-08-2011 at 02:49 PM.
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