COV Loss Control Articles: Wood Chipper Safety

Wood Chipper Safety

October 2007

Overview

This article addresses issues that agencies should consider and key practices to implement when employees are required to operate wood chippers. Applicable Occupational Safety and Health Administration/Virginia Occupational Safety and Health (OSHA/VOSH) standards and manufacturers’ best practices for safe operation of the machinery are discussed. The article includes elements that constitute an exceptional program including inspections, training, safety rules, and personal protective equipment (PPE) selection. Resources for additional information are also included.

What Exactly Is a Wood Chipper?

A wood chipper is a piece of equipment designed to shred tree branches and debris into mulch by feeding the materials into a chute that leads to a rotating blade. The maximum size of the tree or limb depends on the type and size of the equipment.

What’s the Importance of this Issue?

According to the Centers for Disease Control (CDC), “31 occupational deaths were attributed to mobile chippers”¹ from 1992-2002. During these years, more than 2,000 injuries resulted from working with chippers, averaging 204 incidents per year². Potential injuries associated with operating and working around wood chippers include cuts, scrapes or amputations caused by being caught in machines, struck by falling/flying debris, and from contact with the rotating blades inside the machine.

Which OSHA/VOSH Regulations Should be Considered?

There is no single standard providing direction for all aspects of wood chipper operations. The employer should consider various standards as well as industry best practices and manufacturers’ instructions to develop an outstanding program designed to best inform and protect employees operating a wood chipper. Regulations supporting safe operation of wood chippers can be found in OSHA/VOSH 29 Code of Federal Regulations (CFR).

1910.95, Occupational noise exposure which outlines how to protect employees exposed to high noise environments;

1910.133, Eye and face protection which identifies eye and face protection necessary for exposures to flying debris;

1910.136, Occupational foot protection which identifies types of footwear appropriate for the work environment;

1919.138 Hand protection which provides direction and considerations for protecting employees’ hands;

1910.147, The control of hazardous energy (lockout/tagout) which applies to service or maintenance on hazardous machinery;

1910.212, Machinery and Machine Guarding - General requirements for all machines which provides requirements for guarding moving parts of machinery;

1910.265, Sawmills which provides additional operating and PPE considerations for activities like wood chipping; and

1910.266, Logging Operations which also provides additional direction for operation, guarding, and lockout/tagout.

The American National Standards Institute (ANSI) also provides safety requirements in ANSI Z133.1–1994, American National Standard for Tree Care Operations—Pruning, Trimming, Repairing, Maintaining, and Removing Trees, and Cutting Brush.

Training and Best Practices

Employees operating a wood chipper and those working in the area assisting the operators must be properly trained. Specific training information can be obtained from the manufacturer’s operating manual and should address:

The machine’s safety features and emergency stop controls,

Safety decals and their meanings,

Locations and purpose of machine guards,

Required PPE with written PPE hazard assessments,

Conducting pre-use inspections to ensure all components are operational,

Feeding techniques including appropriate body positioning and manufacturer’s recommended tools for feeding materials,

General operating procedures, and

Inspecting the work area around the chipper to keep it free of hazards.

Additionally, employees working in extreme temperatures should be trained to identify the signs and symptoms of heat- or cold-related illnesses. To ensure that employees are alert at all times and to prevent mistakes caused by these conditions or fatigue while operating this dangerous equipment, frequent breaks should be taken.

General operating procedures should also address best practices such as putting leaves and very small twigs directly into the mulch pile instead of trying to push them through the wood chipper and using long branches or a plank as a push stick, if one is not provided, to feed the smaller branches and limbs into the machine. The machinery should be regularly inspected and maintained to prevent an equipment failure or malfunction that could cause employee injury.

An appropriate number of employees should also be selected for the chipper operation. Employees should never operate the machinery alone. Safe work rules should be enforced at all times. Any unsafe activity, including horseplay, should be considered serious and appropriate disciplinary action taken.

Recommended PPE

As with all tasks requiring PPE, the employer is required by OSHA/VOSH to conduct written PPE hazard assessments identifying the hazards of a particular task and the required PPE to protect the employee performing the task.

Employees operating wood chipper equipment should, at a minimum, wear

Hardhat,

Eye protection,

Hearing protection, and

Safety shoes/work boots.

If work gloves are used to protect the hands, they should be cinched tight to provide a close fit. This is critical to prevent tree limbs from accidentally “grabbing” the glove and pulling the employee into the machine. Loose fitting clothing and hanging jewelry should not be worn while participating in wood chipping operations.

Safe operation of a wood chipper - or any piece of equipment - begins with proper planning and preparation long before the power is turned on and the work begins. A thorough hazard analysis, training program, appropriate PPE, and employee understanding of the dangers of improper operation of the wood chipper will help to protect employees from falling victim to the deadly blades of the “beast within.”

¹Centers for Disease Control. (December 10, 2004). Fatal and Nonfatal Occupational Injuries Involving Wood Chippers-United States, 1992-2002. Morbidity and Mortality Weekly Report, 53(48);1130-1131. Retrieved September 4, 2007, from http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5348a2.htm.

²Ibid

Resources

Centers for Disease Control. (December 10, 2004). Fatal and Nonfatal Occupational Injuries Involving Wood Chippers-United States, 1992-2002. Morbidity and Mortality Weekly Report, 53(48);1130-1131. Retrieved September 4, 2007, from http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5348a2.htm.

DR Power. (n.d.). DR Chipper Operating Tips. Retrieved September 25, 2007, from http://www.drpower.com/contentpages/CSTM_CPR_practices.aspx.

National Institute of Occupational Safety and Health. (n.d.). Injury Associated with Working Near or Operating Wood Chippers. Hazard ID. Retrieved September 4, 2007, from http://www.cdc.gov/niosh/hid8.html.

RenTrain. (n.d.). Wood Chipper Safety- Chipper/Shredder. Retrieved September 25, 2007 from http://www.rentrain.com/adams-rental/chipper.php.

Tennessee Saw and Knife. (n.d.). Brush Chipper Knives-Wood Chipper Safety. Retrieved September 24, 2007 from http://www.tskgrinding.com/wood_chipper_safety.asp.