NIOSH logo and tagline

Truck Driver Electrocuted when the Discharge Chute of a Hay Grinder Contacts 7200 Volt Power Line

FACE Investigation 91CO084


A 31-year-old truck driver was electrocuted when the discharge chute of the hay grinder he was moving came into contact with a 7200 volt power line. The victim was positioning a truck-mounted hay grinder when the elevated end contacted the overhead service line. The victim was preparing his equipment to grind one-ton bales of hay. The grinder is mounted on a semi-trailer and is equipped with a hydraulically operated discharge chute that can be raised to accommodate various trucks that haul the ground hay. The victim was standing on the ground operating the hydraulic controls for the chute. As he raised the chute to allow clearance for the hauling trucks, the top edge of the chute contacted the power line. The Colorado Department of Health (CDH) investigator concluded that, in order to prevent future similar occurrences, employers should:

  • survey the work site to identify hazards posed by the locations of overhead electrical lines. All employees should then be informed of the possible hazards.
  • affix safety signs onto the equipment to warn the user of potential hazards of overhead power lines.


On March 16, 1991 a self-employed truck driver was electrocuted when the discharge chute of a hay grinder he was raising contacted a 7200-volt power line.

This fatality was reported to the Colorado Department of Health (CDH) by a local health department that had read about the incident in the newspaper. The CDH investigator initiated an investigation. The partner of the victim was contacted and photographs were taken at the site of the incident.

The victim in this incident was a self-employed individual who had entered into a partnership with the owner of the hay grinder. One additional individual was employed by the partnership. The partnership did not have a written safety policy or a designated safety officer. Formal training for employees is not provided by the company.


On the morning of the incident, the victim and his helper had been contracted to grind one-ton hay bales for an area farmer. The victim had parked his equipment parallel to a 7200-volt power line and was standing on the ground at the rear of the equipment using the hydraulic controls to position the discharge chute of the hay grinder. It is believed that his attention was on the lower edge of the chute as he raised it. The chute must be raised to a height sufficient to allow other trucks to drive under it in order to load the ground hay. As the chute was raised, the upper edge contacted the high-voltage line. The electrical current passed through the equipment, entered the victims hands that were on the controls and exited through the victims feet. The vehicle was not grounded thus the victim’s body provided the direct path to ground for the current. The local ambulance company was called and the victim was transported to a local hospital where he was declared dead on arrival.


The cause of death was determined to be electrocution.


Recommendation #1: Employers should conduct a job site survey on a regular basis to identify potential hazards, implement appropriate control measures, and provide subsequent training to employees that specifically addresses all identified site hazards.

Discussion: The location of the uninsulated power line was not taken into consideration when the hay grinder was positioned. The worksite had sufficient area to locate the equipment in a position that would have provided ample clearance for maneuvering the chute.

Recommendation #2: Affix safety signs to equipment to warn users of the hazards involved when elevating equipment in the proximity of overhead power lines.

Discussion: The use of an appropriate safety sign in this incident could have served to remind the victim of the potential hazard that existed.

Please use information listed on the Contact Sheet on the NIOSH FACE web site to contact In-house FACE program personnel regarding In-house FACE reports and to gain assistance when State-FACE program personnel cannot be reached.