Safeguarding Woodworking Machines and Worker Safety

A detailed description of machinery safeguarding techniques - 1984

The following is a summary of a presentation given by Ryszard Szymani, Director of the Wood Machining Institute, at the Forest Products Research Society Pacific Southwest Section Meeting in Stockton, California, April 11-12, 1984. Reprinted, with permission, by Wood Machining News

Basic Principles of Safeguarding
The list of possible woodworking machinery related injuries is as long as it is horrifying. The majority of these accidents occur on circular sawing machines. Other machines such as vertical spindle moulding and routing machines and hand-fed planning machines, account for most of the remainder.

Safeguards are essential for protecting workers from needless and preventable injuries. Unless a danger point or area is safe by virtue of its position, any machine part, function or process which may cause injury must be safeguarded. A proper safeguard eliminates or reduces danger before access to the danger point or area can be achieved. An overview of various approaches to machine safeguarding is given elsewhere.

Requirements for Safeguards
Safeguards must meet the following minimum requirements in order to be effective:

  • prevent hands, arms, or any other part of a worker’s body from coming in contact with dangerous moving parts

  • be made of durable material and be firmly secured to the machine

  • create no new hazards or interference

  • allow safe lubrication, if possible without removing the safeguard
  • Methods of Machine Safeguarding
    Safeguards can be grouped under five general classifications:

  • Guards: fixed, interlocked, adjustable, self-adjusting

  • Devices: presence sensing, safety trip controls, gates

  • Location/distance: enclosure walls and fences, positioning of the operator’s control station at a safe distance

  • Automatic feeding and ejection methods

  • Miscellaneous aids such as awareness barriers may provide the operator with an extra margin of safety.
  • Analysis of field survey data conducted by Boot, regarding actual machine guarding practices, showed that approximately one out of four companies were not using the standards that are available to them. If these companies are not aware of the specifications required for machine guarding, then it is unlikely that proper guarding techniques will be used.

    Overall average figures from this survey show that 29 percent of the woodworking machines had no or inadequate point-of-operation guards. Exposed power transmission components were observed on 16 percent of the machines. Inadequate operating controls were found on 13 percent of the machines.

    Machinery Maintenance and Repair
    Good maintenance and repair procedures can contribute significantly to the safety of the maintenance crew as well as to that of machine operators.

    In situations where the maintenance or repair personnel would necessarily be exposed to electrical elements or hazardous moving machine parts in the performance of the job, the power source must be shut off and locked out before the work begins.

    Operator Training
    Even the most elaborate safeguarding system cannot offer effective protection unless the worker knows how to use it and why. In his article, Lenckus lists several accidents due to lack of proper operator training. A young woman lost her left index finger in a table saw accident. She had received less than five minutes of instruction from a fellow employee. In another case an instructor in the U.S. used sign language to train a Portuguese-speaking employee to operate a table saw but neglected to explain the use of the guard. Soon afterward the employee crippled his right hand in the saw which was without a guard. A saw blade guard lay a few feet from the machine at the time of the accident.

    The operator should receive instruction or hands-on training in the following:

  • Identification of hazards associated with particular machines

  • Safeguards themselves and how they provide protection

  • How and why to use the safeguards

  • How and when safeguards can be removed, and by whom

  • What to do if a safeguard is damaged, missing, or inadequate
  • This type of safety training is necessary for new operators and maintenance or setup personnel or when workers are assigned to a new machine or operation

    Cooperation and Assistance
    Safety in the workplace demands cooperation and alertness on everyone’s part. Supervisors, operators, and other workers who notice hazards in need of safeguarding, or existing systems that need repair, should notify the appropriate authority immediately.

    The author, R. Szymani, has extensive experience in wood machining.
    In the past 20 years, he has investigated accidents involving woodworking machinery and cutting tools, and served as an expert witness in product liability cases. He has also served for twelve years on the ANSI Accredited Standards Committee 01 involved with safety requirements for the woodworking industry. Szymani publishes Wood Machining News, a bi-monthly newsletter designed to inform users and manufacturers of cutting tools and equipment about the latest worldwide developments in the wood machining field. Subscription Information