Unless helmet has visible damage and you showed someone it before you left building
where does the law stand on such matters?
Forget it, it's just one of them things.
Unless you have grounds for believing a contributory factor in the incident was that the door was defective in some way or lighting should have been better or that operating the door required training that the company failed to provide, I can't see that a claim against them will stand much chance of success.
is the door had been hung so that it did not open up into a thoughfare but back towards the person opening the door this would not occur !?!Have you requested permission to carry that equipment that is not work related into your work building?As you are aware that doors leading to this area open outward why were you carrying this item in the hand closest to the door opening where it could be damaged if the door was opened.Is the area you were walking down confined enough to make you walk close enough to the wall/ door to be with in the opening radius of the door or could you have been walking further from the wall/ door to avoid a collision if the door was opened.