go to MCAS (motorcycle accessory supermarket) on wentworth avenue in the city or at parramatta. they have the widest range.
all motorcycle helmets on sale should have AS1698 sticker on them. this test is a fairly basic one where they drop a weight on top and check the compression of the foam. Even the made in china HJC will pass this test, as will those ridiculous pudding bowl things that the hardly ridables seem to fancy.
Obviously the more you pay, the more features you get. Ventilation adds to cost but is like udders on a bull when you are using it in a nice environment like a car. graphics add to the cost, but who cares if it is inside the car, its not like you are going to be in F1 and they use your helmet colours to identify you. Things like removable linings that allow you to wash them are nice, but given your intended frequency of use is probably not a concern.
There are two basic shell types - polycarbonate is cheaper, composites of various kinds go up in price. A kevlar/glass composite one is what i have, but i ride a motorcycle every day and it is because of the wear properties of the kevlar that i went this way. Basically i can slide along on the helmet and it wont wear through, not a consideration for in the car. unless you intend getting thrown out

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The compression foam is what its all about in the car application, and most helmets have basically the same stuff, so are just as resistant to impact as the next.
Make sure that the helmet you get fits your head. and by this i mean shape as well as size. Not all helmets, even from the same manufacturer have the same internal shape, just like no two human heads are the same. If you need to wear glasses under the helmet as i do, then you need to try the helmet with the glasses. It is important that it is snug but comfortable, the sales people will help you with this.
I also prefer to have a chin strap that fastens by folding it through two metal loops. I have found this more secure than the buckle type that you see on the cheaper helmets.
As to brands, i have a Shoei at the moment, retails about $700, but like i said i use it every day. My previous two helmets were Fimez FM superbike ones that were Snell90 standard (second highest euro standard, only higher is F1 types). The first one i used when i high sided the bike. I highly recommend them.
cheers
michael
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66 Mini Minor sponsored by
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