Guidelines for Machine Safeguarding
The Occupational Safety and Health Administration (OSHA) requires that machine guarding be provided and maintained in a manner sufficient to protect machine operators and other persons present in machine areas from hazards associated with the operation of machines. Such hazards include those created by points of operation, in-running nip points, rotating parts, flying chips and sparks. The following information is provided to assist machine operators and machine shop supervisors and managers in carrying out their responsibilities for assuring machine safety through hazard identification and evaluation, safeguarding, and safe operation.
Types and Points of Hazardous Machine Operations
• Rotating: in-running nip points, spindles, shaft ends, couplings
• Reciprocating: back-and-forth, up-and-down
• Transverse: movement in a straight, continuous line
• Cutting: bandsaws, drills, milling machines, lathes
• Punching: punch presses, notchers
• Shearing: mechanical, pneumatic, or hydraulic shears
• Bending: press brakes, tube benders, plate rolls
Machine safeguards should be installed and maintained to ensure that they:
• PREVENT CONTACT - Safeguards must minimize the possibility of the operator or another worker placing their hands into hazardous moving parts.
• REMAIN SECURE - Workers should not be able to easily remove or tamper with the safeguard.
• PROTECT FROM FALLING OBJECTS - Safeguards should ensure that no objects can fall into moving parts.
• CREATE NO NEW HAZARDS - A safeguard defeats its purpose if it creates a hazard of its own.
• CREATE NO INTERFERENCE - A safeguard should not create an unacceptable impediment for the worker.
* ALLOW SAFE MAINTENANCE AND LUBRICATION - It should be possible to lubricate the machine without removing the safeguard.
Types of Machine Safeguards
• Barriers and guards that prevent contact with machinery.
• Mechanical or electrical devices that restrict contact, such as presence-sensing, restraining, or tripping devices, two-hand controls, or gates.
• Feeding and ejection methods that eliminate part handling in the hazard zone.
• Aids such as awareness signs that do not provide physical protection, but warn of a danger area.
Common Elements for Safeguarding All Machines
Job Hazard Analysis
A job hazard analysis can be performed for all jobs in the workplace, whether the job task is “special” (non-routine) or routine. Even one-step jobs – such as those in which only a button is pressed – can and perhaps should be analyzed by evaluating surrounding work conditions.
To determine which jobs should be analyzed first, review your job injury and illness reports. Obviously, a job hazard analysis should be conducted first for jobs with the highest rates of disabling injuries and illnesses. Also, jobs where “close calls” or “near misses” have occurred should be given priority. Analyses of new jobs and jobs where changes have been made in processes and procedures should follow. Eventually, a job hazard analysis should be conducted and made available to employees for all jobs in the workplace.
Involving the Employee
Once you have selected a job for analysis, discuss the procedure with the employee performing the job and explain its purpose. Point out that you are studying the job itself, not checking on the employee’s job performance. Involve the employee in all phases of the analysis – from reviewing the job steps and procedures to discussing potential hazards and recommended solutions. You also should talk to other workers who have performed the same job.
Conducting the Job Hazard Analysis
Before actually beginning the job hazard analysis, take a look at the general conditions under which the job is performed and develop a checklist. Below are some sample questions you might ask.
• Are there materials on the floor that could trip a worker?
• Is lighting adequate?
• Are there any live electrical hazards at the jobsite?
• Are there any chemical, physical, biological, or radiation hazards associated with the job or likely to develop?
• Are tools – including hand tools, machines, and equipment – in need of repair?
• Is there excessive noise in the work area, hindering worker communication or causing hearing loss?
• Are job procedures known and are they followed or modified?
Naturally this list is by no means complete because each worksite has its own requirements and environmental conditions. You should add your own questions to the list. You also might take photographs of the workplace, if appropriate, for use in making a more detailed analysis of the work environment.
Breaking Down the Job
Nearly every job can be broken down into job tasks or steps. In the first part of the job hazard analysis, list each step of the job in order of occurrence as you watch the employee performing the job.
Be sure to record enough information to describe each job action, but do not make the breakdown too detailed. Later, go over the job steps with the employee.
After you have recorded the job steps, next examine each step to determine the hazards that exist or that might occur. Ask yourself these kinds of questions.
• Is the worker wearing personal protective clothing and equipment, including safety harnesses that are appropriate for the job?
• Are work positions, machinery, pits or holes, and hazardous operations adequately guarded?
• Are lockout procedures used for machinery deactivation during maintenance procedures?
• Is the worker wearing clothing or jewelry that could get caught in the machinery or otherwise cause a hazard?
• Are there fixed objects that may cause injury, such as sharp machine edges?
• Is the flow of work improperly organized (e.g., Is the worker required to make movements that are too rapid)?
• Can the worker get caught in or between machine parts?
• Can the worker be injured by reaching over moving machinery parts or materials?
• Is the worker at any time in an off-balance position?
• Is the worker positioned to the machine in a way that is potentially dangerous?
• Is the worker required to make movements that could lead to or cause hand or foot injuries, or strain from lifting – the hazards of repetitive motions?
• Can the worker be struck by an object or lean against or strike a machine part or object?
• Can the worker be injured from lifting or pulling objects, or from carrying heavy objects?
Recommending Safe Procedures and Protection
After you have listed each hazard or potential hazard and have reviewed them with the employee performing the job, determine whether the job could be performed in another way to eliminate the hazards, such as combining steps or changing the sequence, or whether safety equipment and precautions are needed to control the hazards. An alternative or additional procedure is to videotape the worker performing his or her job and analyze the job procedures.
If safer and better job steps can be used, list each new step, such as describing a new method for disposing of material. List exactly what the worker needs to know to perform the job using the new method. Do not make general statements about the procedure, such as “Be Careful.” Be as specific as you can in your recommendations.
You may wish to set up a training program using the job hazard analysis to retrain your employees in the new procedures, especially if the are working with highly toxic substances or in hazardous situations. (Some OSHA standards require that formal training programs be established for employees.)
If no new procedures can be developed, determine whether any physical changes – such as redesigning equipment, changing tools, adding machine guards, personal protective equipment, or ventilation – will eliminate or reduce the danger.
If hazards are still present, try to reduce the necessity for performing the job or the frequency of performing it. Go over the recommendations with all employees performing the job. Their ideas about the hazards and proposed recommendations may be valuable. Be sure that they understand what they are required to do and the reasons for the changes in the job procedures.
Revising the Job Hazard Analysis
A job hazard analysis can do much toward reducing accidents and injuries in the workplace, but it is only effective if it is reviewed and updated periodically. Even if no changes have been made in a job, hazards that were missed in an earlier analysis could be detected.
If an illness or injury occurs on a specific job, the job hazard analysis should be reviewed immediately to determine whether changes are needed in the job procedure. In addition, if a “close call” or “near miss” has resulted from an employee’s failure to follow job procedures, this should be discussed with all employees performing the job.
Any time a job hazard analysis is revised, training in the new job methods, procedures, or protective measures should be provided to all employees affected by the changes. A job hazard analysis also can be used to train effectively new employees on the steps and job hazards.
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 or improvement, should notify the proper authority immediately.
Supervisors have these additional, specific responsibilities with regard to safety in the workplace; encouraging safe work habits and correcting unsafe ones; explaining to the worker all the potential hazards associated with the machines and processes in the work area; and being responsive to employer requests for action or information regarding machine hazards. The first-line supervisor plays a pivotal role in communicating the safety needs of the worker to management and the employer’s safety rules and policies to the worker.
Sometimes the solution to a machine safeguarding problem may require expertise that is not available in a given establishment. The readers of this manual are encouraged to find out where help is available and, when necessary, to request it.
The machine’s manufacturer is often a good place to start when looking for assistance with a safeguarding problem. Manufacturers can often supply the necessary literature or advice. Insurance carriers, too, will often make their safety specialists available to the establishments whose assets they insure. Union safety specialists can also lend significant assistance.
Some government agencies offer consultation services, providing for onsite evaluation of workplaces and the recommendation of possible hazard controls. OSHA funds one such program, which is offered free of charge to employers in every state. Delivered by state governments or private contractors, the consultation program is completely separate from the OSHA inspection effort; no citations are issued and no penalties are proposed. The trained professional consultants can help employers recognize hazards in the workplace and can suggest general approaches for solving safety and health problems. In addition, the consultant can identify sources of other available help, if necessary.
Anyone with questions about Federal standards, about the requirements for machine safeguarding, or about available consultation services should contact OSHA.