If you are present at the scene of an accident, one of the most important things to do is keep calm. Check to see how severe the injuries are and see if anyone involved requires first aid. If the injury is superficial, help the victim back down the mountain to seek medical attention.
If the injury is more serious, place markers several metres uphill of the injured party - to stop anyone running into them and making matters even worse. Cross your skis upright in the snow (or place your board upright in the snow) so that people can see the obstacle from a distance and can therefore avoid it. Make sure the skis are clearly visible from uphill (white ski/board soles are not).
Release the casualty's bindings if they are not already off. Leave their boots on unless there is a particular reason to remove them. Never try to move the casualty to give treatment, and put them in the recovery position - on their side - only if you are certain they haven't sustained any skeletal injury. Try to keep them as warm as possible - cover them with your jacket if they are cold.
If you are with a group of other skiers and boarders, you must nominate one of the group to go and get help - the lift operators at the bottom or the top of the nearest lift will be able to contact the ski patrol. It is essential that the person going for help is a competent skier or boarder and can identify where the accident victim is (naming the piste if possible) - it's not much help if the mountain rescue services don't know where to go. They should also be able to tell the ski patrollers what sort of injury it is. If you are not with a group, flag down a passer-by to go and get help.
If you stay behind while someone goes to get help, you should try to minister to the injured party as best you can. Let them know that help is on the way and try to make them as comfortable and cheerful as possible while you wait for it to arrive. If they are showing signs of shock, try to get them to lie with their head downhill - lower than their feet.
If the injury is a lot more serious, you may have to try to use first aid yourself. Check to see that the victim is breathing. If not you will have to try to administer artificial respiration - check that their airway is not blocked (by their tongue or vomit, or in the case of avalanche victims - snow). Give them 'the kiss of life' until they start to breathe again or help arrives. If there is severe bleeding, apply pressure to the wound with some sort of pad - hold this in place until help arrives.
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