From the Canadian accident report posted by Bertie Thruster -
Transportation Safety Board of Canada - Aviation Investigation Report A12O0030
The second most frequently injured body region in survivable helicopter crashes is the head. According to United States military research, the risk of fatal head injuries can be as high as 6 times greater for helicopter occupants not wearing head protection. The effects of non-fatal head injuries range from momentary confusion and inability to concentrate to full loss of consciousness. Incapacitation can compromise a pilot’s ability to escape quickly from a helicopter and to assist passengers in an emergency evacuation or survival situation. The TSB has documented a number of occurrences in which the use of head protection likely would have reduced or prevented the injuries sustained by the pilot.
In Canada, Aviation Occupational Health and Safety Regulations (SOR/2011-87) are issued pursuant to the Canada Labour Code. These regulations apply with respect to employees employed on board aircraft while in operation and with respect to persons granted access to those aircraft by the employer. Section 6.4 of the Aviation Occupational Health and Safety Regulations states that if there is a risk of head injury, protective headwear shall be used. Although not required by regulation to do so, helicopter operators may conduct a risk assessment to ascertain the level of risk of head injury associated with their operations, to determine if headwear is required.
There is no CARs requirement for helicopter pilots to wear protective headgear. As most pilots flying for KMH voluntarily wore helmets, the company’s assessment of risk did not result in a policy requiring mandatory use of helmets. Pilots provided their own helmets, and the accident pilot was considering purchasing a helmet at the time of the accident.
In recognition of the benefits of head protection, a resolution passed by the Helicopter Association of Canada (HAC) Board of Directors on 27 June 2011 stated that:
HAC strongly recommends to its Operator-Members that they should promote the use of helmets for helicopter flight crew members under all operational circumstances which permit their use. HAC also points out, however, that certain pilot/aircraft type configurations may preclude safe helmet use.