Moving machine parts have the potential to cause severe workplace injuries. Injuries most often occur when workers operate unguarded or inadequately safeguarded machinery. Any machine part, function, or process that may cause injury must be safeguarded so that the hazards are eliminated or controlled.
Industrial workplaces such as garage workshops, metal fabrication and welding shops, and mechanical or heavy manufacturing facilities will have a variety of machines and tools. Some of the tools may be as simple as a table saw or box fan and sometimes they can be complex and partially robotic or involve hazardous chemicals. Workers responsible to operate, repair, clean, or just work near these machines and tools must be protected from potential hazards.
OSHA Standard 1910.212(a)(1) One or more methods of machine guarding shall be provided to protect the operator and other employees in the machine area from hazards such as those created by point of operation, ingoing nip points, rotating parts, flying chips and sparks.
Machine guards are critical to the safety of workers. Machine guarding shields, devices, and safety features cover the hazardous areas, functions, or processes of machinery and prevent injury to the machine operator, and other workers nearby. Many times, workers do not realize the dangers that they are protected from because of a simple steel or acrylic guard. For this reason, workers should be familiar with the potential hazards introduced when machines with rotating parts, gears, or pulleys are used.
Moving machine parts have the potential to cause severe workplace injuries including:
- Caught-in, Crushed-by, and Mangled-by Injuries
- Bruises, Strains, and Sprains
- Abrasions, Lacerations, and Amputations
- Eye Injuries and Blindness
- Shocks and Electrocutions
- Struck-by Injuries
- Injuries so severe they result in death
Recognizing the potential hazards of machines starts with understanding the first place where the potential for injury exists – this is the “point of operation.” According to OSHA the point of operation is the area on a machine where work is actually performed upon the material being processed.
OSHA Standard 1910.212(a)(3)(i) Point of operation is the area on a machine where work is actually performed upon the material being processed.
Workers have to be protected from point of operation hazards, power transmission apparatus such as pulleys and chains, and other moving or rotating parts that pose danger to the operator. Workers should be familiar with the potential hazards introduced when machines with rotating parts, gears, or pulleys are used.
Safe and effective machine guarding is secure, tamper-resistant, and durable. Machine guarding should prevent contact with the hazards of the machine while not interfering with the normal operation of the machine and not creating any additional hazards.
OSHA Standard 1910.212(a)(2) Guards shall be affixed to the machine where possible and secured elsewhere if for any reason attachment to the machine is not possible. The guard shall be such that it does not offer an accident hazard in itself.
There are a variety of ways that workers could be protected from machine and point-of-operation hazards – some techniques require special training in order to ensure the safety of the operator.
Fixed Guards – made of acrylic, metal, or even plastic that are bolted, welded, or locked in place provide stable protection from moving parts.
Adjustable Guards – self-adjusting or manually adjustable guards that allow the material to be of multiple sizes or shapes but still protect the worker.
Interlocked or Sensors – sometimes combined with adjustable or removable guards, interlocks or sensors can be set to instantly shut off power to a machine. Sensors may be designed to shut off a machine or tool as soon as a visible or invisible barrier is broken.
Safety Trip Controls – similar to interlocks or sensors these devices can be in the form of metal bars, steel cables or wires, and floor mats or gates that are designed to trip and shut off power to a machine if a worker touches, steps, or enters a danger area.
Restraints and Pullbacks – devices such as wrist straps and safety ropes attached to specific points to keep the worker from getting too close to a point of operation hazard.
Only trained and authorized machine operators should be close to the machinery and all other workers must remain at a safe distance. If an employee who is not the machine operator needs to approach a piece of equipment, they should make eye contact with the operator and use clear hand signals to indicate they are approaching.
Machine operators, or those who work in a facility near machines, should wear personal protective equipment (PPE) recommended by the manufacturer and avoid wearing loose-fitting clothing, dangling jewelry, hanging badges, or long hair that could get caught in moving parts.
OSHA Standard 1910.133(a)(2) The employer shall ensure that each affected employee uses eye protection that provides side protection when there is a hazard from flying objects.
IMPORTANT: During the safety meeting or toolbox talk on Machine Guarding, it is important to emphasize that no one should ever tamper with or remove a machine guard, sensor, or safety device. Only personnel that have received specific training and follow the correct procedures are authorized to remove, repair, or modify a machine guard.
Equipment should be de-energized when not in use to keep the machine from accidentally starting. The lockout/tagout procedure is especially important when doing any kind of work on the equipment such as repairs, changing accessories, or performing routine maintenance.
More information on Machine Guarding can be found on OSHA's website at osha.gov and at the specific links provided below.
OSHA Quick Card Protect Yourself: Amputations
OSHA Fact Sheet Amputations
OSHA eTool Machine Guarding
OSHA Booklet Safeguarding Machines and Protecting Employees