Alaska FACE Investigation 96AK035
February 23, 1997
Ski Patrol/Guide Crushed by Snow Cat During Ski Trail Grooming Operations -- Alaska
On November 8, 1996, a 29-year-old male ski patrol/guide (victim) died from injuries after he was run over by a tracked vehicle (snow cat) during trail building/snowgrooming operations. The victim had been riding in the rear passenger compartment of a snow cat being used for routine grooming of ski trails. During a pass down a hill, the operator stopped the vehicle in order evaluate their progress and change direction. Communication between the two compartments was restricted to visual hand signals. Rear perimeter visibility from within the operator's compartment was severely limited. The victim, having exited the rear compartment, was in back of the vehicle when he was struck. A co-worker (witness) in the front compartment passenger seat felt a bump and noticing a red spray, alerted the operator to stop the vehicle. The victim was pinned under the track vehicle and sustained severe head trauma. The witness ran to the ridge and yelled down that there was an accident and he needed an ambulance. The victim was pronounced dead at the scene by a responding physician who was snowmobiling in the area. It was surmised that the victim, having exited with his skis, had returned for his ski poles when he was run over.
Based on the findings of the epidemiologic investigation, to prevent similar occurrences, employers should:
Additionally, equipment manufacturers should:
On November 11, 1996, a 29-year-old male ski patroller/guide (victim) died after being run over by a snow cat during initial trail building/snowgrooming operations. The victim suffered severe head injuries and was declared dead at the scene. The Alaska Division of Public Health, Section of Epidemiology was notified by the National Institute of Occupational Safety and Health, Alaska Activity on December 09, 1996. An investigation involving an Injury Prevention Specialist from the Alaska Department of Health and Social Services, Division of Public Health, Section of Epidemiology ensued on December 18, 1996. The incident was reviewed with Alaska Department of Labor (AKDOL) officials. Medical examiner and Alaska State Troopers reports, as well as AKDOL reports were obtained.
The ski touring operation in this incident was privately owned and employed six workers, including two ski patrollers. The victim had worked for the ski touring operation as a ski guide/patroller since the business began operations in 1993. At the time of the incident, the victim and two co-workers, the lead snow cat operator and the lead ski patroller/guide, were participating in trail maintenance and had worked together for four or five seasons.
The owner/president did not have a written safety program. A written operating plan which included a daily operating outline, snow cat operations procedures, and communications procedure was available. Employee duties were not specifically listed in the operating plan. However, operations procedures for the snow cat, including boarding/disembarking and clearance information, were mentioned. This was the first fatality experienced by this company.
The incident occurred at a site 250 feet up slope from the road leading from the ski lodge/base facilities. The ski touring operation provided transportation to remote ski areas in the mountainous terrain. After safety briefings including procedures when near or traveling in the snow cat, use of avalanche beacons, and other backcountry skiing procedures, clients and staff members travelled to drop-off points in the high alpine tundra. Part of the operation included routine use of ski patrollers for avalanche evaluation and safety/accident response. As part of their assigned duties, ski patrollers provided avalanche hazard recognition by evaluating the snow pack and terrain.
The terrain used for the touring operation had ten ski run areas. Travel to and from these areas was by a snow cat. The snowcat was a 1989 model with a 1993 model cab and passenger compartment which was purchased as a single unit (figure 1 and 1a). The front cab contained two seats separated by a console. Entry to the passenger compartment was via a door at the rear of the compartment. The rise into the passenger compartment was 43 inches with a 15 inch clearance between track. The step assembly used to access the passenger compartment was detached during trail building/grooming operations. The track width on the vehicle was 66 inches. Windows were located on the side and front sections of the passenger compartment; the front passenger windows were above the operator's compartment. Rear-view mirrors were attached to both sides of the front cab. A backup alarm was also in place. No modifications or alterations were made to the unit after purchase.
On the day of the incident, the victim, the lead ski patroller/guide (the witness), and the lead snowcat operator arrived at the base facilities. This was to be the first day of trail building/grooming for the season. The witness, the operator, and a small child boarded the front cab while the victim rode in the passenger compartment. Since voice communication was not possible, hand signals were used to communicate to the victim through the passenger compartment window from the front cab.
During a brief break in the operation, the operator paused the snow cat on a bench area of a downward slope, without idling down the engine or dropping the blade. The operator decided to traverse the area higher on the ridge. The witness signaled the victim that they were turning around. The victim responded with a thumbs up motion. Sometime prior to the operator placing the vehicle in reverse gear, the victim departed the passenger compartment. As the vehicle moved backward approximately 45 feet and then turned to the right (figure 2), the witness felt a bump and saw a red spray which he assumed was hydraulic fluid. He immediately signaled the operator to stop. The victim was found entangled in the inside right track. The witness checked the victim for a pulse. Finding none, the operator moved the snow cat forward to bring the victim to the rear of the vehicle. Emergency medical services were summoned; however, the victim suffered severe head injuries and was pronounced dead at the scene. The victim's skis were found in an upright position to the right of the snow cat. It was surmised that the victim had returned to the passenger compartment to retrieve his ski poles.
CAUSE OF DEATH
The medical examiner's report listed the cause of death as blunt force injuries - track vehicle incident.
Recommendation #1: Employers should develop, implement, and enforce a comprehensive written safety program.
Discussion: The development, implementation, and enforcement of a comprehensive written safety program should identify, and reduce or eliminate, worker exposures to hazardous situations. The safety program should include worksite and equipment hazard assessments to facilitate safe practices of employees.
Recommendation #2: The employer should consider installing voice communication devices inside the separate compartments of track vehicles so that operators and passengers can communicate without leaving their compartments.
Discussion: During normal operating procedures, staff are issued two-way radios for communication. However, radios were not available on this day. The victim, although in visual communication with the operator's compartment, was not capable of direct voice communication with the operator unless one or both left their compartments. Hand signals may be given by any predetermined, mutually understood manner and are a practical method when voice communication is limited. The addition of two-way voice communication may eliminate misinterpretation or missed signals.
Recommendation #3: The equipment manufacturer should consider equipment engineering designs to detect and warn mobile equipment operators of the potential presence of individuals in the blind spot of the equipment.
Discussion: The snowcat in this incident was equipped with mirrors extending approximately seven inches from both sides and an audible alarm to warn individuals of reverse vehicle motion. While this type of equipment can prevent injury by notifying individuals in proximity of the vehicle, operators were relying on mirrors which had a significant blind area. Angled mirrors attached to the rear of the passenger compartment and fisheye mirror attachments would help reduce the blind areas and broaden peripheral field visibility. In addition, transport vehicles could be equipped with a passenger compartment door sensor to alert the operator of an unsecured rear door.
Figures 1 and 1a. Front oblique and rear view of snow cat
Figure 2. Positions and movement of snow cat at time of incident
To contact Alaska State FACE program personnel regarding State-based FACE reports, please use information listed on the Contact Sheet on the NIOSH FACE web site Please contact In-house FACE program personnel regarding In-house FACE reports and to gain assistance when State-FACE program personnel cannot be reached.