Shell –  Look for cracks or abrasions.  Are there any cracked edges. Check for fading, UV exposure can make the shell brittle.  Any compromise to the integrity of the shell will mean it may not hold together in an impact.

Liner – The foam. Press carefully over the shell of the helmet to see if there is any movement. Some helmets there will be no movement others a little movement, you are looking for any area that there is a variation in movement compared to the rest of the helmet. An area of greater movement indicates damage to the foam under the shell. Turn over the helmet and check the liner for cracks or compressed foam. If you suspect any area of compression check and measure the thickness of the foam at the same spot on the other side of the helmet.

Straps/buckles/clips and fasteners –  check for wear and tear. Any loose stitching or fraying. Check buckles/clips and fasteners do they work and hold – buckle or fasten and then give them good forceful tugs and twists to check they don’t come apart. Think about the force they would be under during an impact or multiple impacts eg car and road. You want to  mimic that force, you need to know that they will work to keep that helmet securely on your head in an impact.

Key point: All foams immediately or eventually deteriorate under impact. This is why it is suggested you never buy a secondhand helmet and you replace your helmet following impact. An accidental drop of your helmet is unlikely to cause damage however it is a good idea to avoid dropping your helmet due to the potential damage. Hard to get the kids working with you on that one but giving them some information and understanding of why it is important, helps.