“GENERAL MACHINE SHOP SAFETY TRAINING”

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PINCH POINTS

 Occur between rotating and fixed parts which can create a shearing, crushing or abrading action.

RECIPROCATING MOTION

The equipment may entrap a worker between a moving and stationary object, during the up, down, back and forth motion.

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TRANSVERSE MOTION

 Creates a hazard when the worker is pulled into the

pinch point or shear point or is dragged by the

moving parts into other moving parts.

CUTTING ACTION (Involves: Rotating,

Reciprocating or Transverse Motions)

Dangers exists at the point of operation where finger, head, and arm injuries occur and where flying chips or scrap material can strike eyes or face.

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PUNCHING ACTION

Results when power is applied to slide for the purpose of blanking, drawing or stamping metal or other materials.

is inserted, held or withdrawn.

Danger of this type of action occurs at the point of operation where the stock

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SHEARING ACTION

Applying power to a slide or knife in order to trim or shear metal or other materials. Hazards

occurs at the point of operation where the stock is inserted, held or withdrawn.

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BENDING ACTION

Applying power to a slide in order to draw or form metal or other materials.

inserted, held or withdrawn. Hazards occur at the point of operation where stock is

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GUARDS

o Physical barriers that prevent access to danger areas.

o Must prevent hands, arms, or any part of the body or clothing from making contact with dangerous moving parts. o Should prevent contact, be secured and well constructed.

o Should protect from falling objects and contain the hazard.

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TYPES OF GUARDS

  Fixed Guards-Are a permanent part of the machine, they are not dependent on moving parts to perform their intended functions.

Interlocked Guards-When opened or removed the tripping mechanism and or power are automatically shut off or disengaged, the machine cannot cycle until replaced.

*   Adjustable Guards-Allow flexibility in accommodating various sizes of stock. Properly adjusted this guard provides protection from point

of operation hazards.

Self-Adjusting Barriers-As the Operator moves stock into the danger area, the guard is pushed away, providing an opening that is only large enough to admit the stock being used. After the stock is removed the guard returns to rest position.

*  Photoelectric (Optical) Presence Sensing Device-Uses a system of light sources and controls which can interrupt the machines operating cycle if the light field is broken, the machine stops and will not cycle. This can only be used on machines which can be stopped before the worker can reach the danger area.

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Presence-Sensing Devices-

o Either stops the machine or will not start if a hand or any body part is inadvertently placed in the danger area. o

P-S Devices create a sensing field that detects the presence of an object larger than an outlined size.

o When the signal is obstructed the P-S sends a stop signal to the machine.

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Radio Frequency (Capacitance) Presence-Sending

Device-Uses a radio beam that is part of the machine circuit control, when the capacitance field is broken the machine will stop or not activate. o This device can only be used on machines which can be stopped before the worker reaches the danger zone.

*  Electromechanical Sensing Device-Has a probe or contact bar which descends to a predetermined distance when the operator initiates the machine cycle. If there is an obstacle preventing it from

descending its full predetermined distance, the control circuit does not actuate the machine.

*  Pull Back Device-Uses a series of cables attached to the operator’s hands, wrist and or arms. Used primarily on machines with a stroking action.

o When the slide or ram is up the operator is allowed access to the point of operation, when the slide or

ram is descending a mechanical linkage withdraws the hands from the point of operation.

o A restraint device uses cables or straps that are attached to the operators hands at a fixed point and are adjusted to allow the operators hands travel within a predetermined safe area.

* * Safety Trip Controls-Are devices that provide a quick means for deactivating the machines in an emergency situation.   A pressure sensitive bar, when depressed will deactivate the machine. If the operator or anyone slips, trips, loses balance or is drawn toward the machine. Applying pressure to the bar will stop operation of machine. It is position sensitive as it has to be activated by the operator during an emergency situation, therefore it’s position is critical to the operator.

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When exposures to hazards cannot be engineered completely out of the process and other forms of Administrative procedures cannot provide additional protection, a supplementary method of control is Personal Protective Equipment.

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PPE is not a substitute for Engineering or Administrative Controls. 29 CFR 1910.132 OSHA Standards set controls for PPE usage.

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Eye and Face Protection

o The employer shall ensure that each affected employee uses appropriate eye or face protection when exposed to eye or face hazards from flying particles, molten materials, liquid chemicals, acids or caustic liquids, chemical gases or vapors or potentially injurious light radiation.

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Respiratory Protection

o A respirator shall be provided to each employee when such equipment is necessary to protect the health of such employee. o The employer shall provide the respirators which are applicable and suitable for the purpose intended. o The employer shall be responsible for the establishment and maintenance of a respiratory protection program, which shall include the requirements outlined in paragraph (c) of this section. The program shall cover each employee required by this section to use a respirator.

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Head Protection

o The employer shall ensure that each affected employee wears a protective helmet ( hard hat ) when working in areas where there is a potential for injury to the head from falling objects.

o The employer shall ensure that a protective helmet ( hard hat ) designed to reduce electrical shock hazard is worn by each such affected employee when near exposed electrical conductors which could contact the head.

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Foot Protection

o The employer shall ensure that each affected employee uses protective footwear when working in areas where there is a danger of foot injuries due to falling or rolling objects, or objects piercing the sole, and where such employee's feet are exposed to electrical hazards.

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Protective footwear must comply with any of the following consensus standards: ASTM F-2412-2005, ANSI Z41-1999, ANSI Z41-1991

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Hand Protection

o Employers shall select and require employees to use appropriate hand protection when employees' hands are exposed to hazards such as those from skin absorption of harmful substances; severe cuts or lacerations; severe abrasions; punctures; chemical burns; thermal burns; and harmful temperature extremes.

*   An Abrasive Wheel is a grinding tool consisting of bonded abrasive grains. Grinding wheels are made of natural or synthetic abrasive materials bonded together in a matrix to form a wheel. o Numerous shapes; flat disks, cylinders, cups, cones and wheels with specific cuts & grits.  Abrasive grains constitute the central component of any grinding wheel and the hardness and friability of the grinding materials will significantly affect the behavior of a given wheel.

 Abrasive wheel hazards that can occur using abrasive wheels include but are not limited to, shock, scrapes, cuts, eye injury and loss, finger injury and loss, hearing loss, head and body wounds. o Wheels can break and become dangerous flying projectiles in a work environment.

o Dust can be a health hazard and employees should were proper PPE when working on materials that create large amounts of dust in the operation.

 Hazards can be created by external factors; o Distractions by someone or something else o o o o o Horseplay in or around work area o Conversations with someone while operating machinery.

o o Reaching across working areas Wearing jewelry (rings or necklaces) Long hair ( not tied up and back) Loose fitting clothing Hot sparks Gloves

*   Mechanical Power Presses are machines that transmit force to cut, form, or assemble metal or other materials through tools or dies attached to or operated by slides. 3 types of Mechanical Power Presses o Mechanical o o Hydraulic Pneumatic

 A Mechanical Press is a machine that exerts pressure to form or shape or cut materials or extract liquids or compress solids.

 A Press is a mechanically powered machine that punches, shears, forms or assembles metal or other materials by means of cutting, shaping or combination of dies attached to slides or rams.  A Press consists of a stationary bed ( or anvil ), and a slide ( or slides ) having a controlled reciprocating motion toward and away from the bed surface, the slide being guided in a defined path by the frame of the press.

 o Major components of a Mechanical Press are; The Frame o o o o o Motor Flywheel Crankshaft Clutch Brake

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AMPUTAIONS

Placing hand into point of operations   Unguarded or inadequately guarded presses Deactivating or over-riding safeguards Safeguards most commonly used: o Barrier guards attached to fixed surfaces o  Presence-Sensing devices Radio Frequency Sensors    Light Curtains Pullback Devices Fixed Guards

*  Robots are machines that load and unload stock, assemble parts, transfer objects or perform other tasks.   They can be used to replace humans who were performing unsafe, hazardous, highly repetitive and unpleasant tasks.

Robots are used to accomplish many different types of application functions such as material handling, assembly, arc welding, resistance welding, machine tool load and unload functions, painting, spraying and other functions.

 Industrial Robots are programmable multifunctional mechanical devices designed to move materials, parts, tools or specialized devices through variable programmed motions to perform task safely.

 Robot injuries do not normally occur during normal operating conditions.

But rather under these conditions: o o o o During programming Program touchup Maintenance or Repair Testing, Setup or Adjustment.

 During many of these operations, the Operator, Programmer or Maintenance Worker may temporarily be within the robot’s working envelope where unintended operations could result in injuries.

 Mechanical hazards include workers : o Colliding with equipment (Robot’s Arm or peripheral equipment) o Being crushed (trapped between the Robot’s Arm or peripheral equipment) o Injured by falling objects ( failure of gripper mechanisms with resultant release of parts )

 Effective Safeguarding of Robotics o The proper selection of an effective robotic safeguarding system should be based upon a hazard analysis of the robot’s system use, programming and maintenance operations. o Among the factors to be included are the tasks a robot will be programmed to perform.

 Start up  Command or programming procedures  Environmental conditions  Location and installation requirements  Possible human error

o  Scheduled and unscheduled maintenance  Possible robot and system malfunctions  Normal mode operations  Personnel functions and duties associated with operation. An effective safeguarding system protects not only the operators but also engineers, programmers, maintenance workers and others who work on or with robot’s systems and could be exposed to hazards with a robot’s operation.

o A combination of safeguarding methods maybe used. Redundancy and backup systems are especially recommended , particularly if a robot or robot system is operating in a hazardous condition or handling hazardous materials. o The safeguarding devices employed should not themselves constitute a hazard or curtail necessary vision or viewing by attending human operators. o Personnel should be safeguarded from hazards associated with the restricted envelope ( space ) through the use of one or more safeguarding devices.

o o o Mechanical limiting devices Non mechanical limiting devices Presence Sensing devices o Fixed Barriers ( which prevent contact with moving parts ) o Interlocked barrier guards

*  The intent of Lockout – Tagout is to safeguard employees from the unexpected startup or machinery or equipment or release of hazardous energy.  Lockout is the placement of a lockout device on an energy isolation device ( circuit breaker, slide gate, line valve, disconnect switch, etc. ) o A lockout device utilizes a positive means such as a lock to hold an energy isolating device in a safe position and prevent re-energization of the machine.

o The lockout device must be substantial enough to prevent removal without the use of excessive force or unusual techniques. o Lockout shall be used unless the employer can demonstrate that the utilization of a tagout system will provide full employee protection.  Tagout is the placement of a tagout device ( tag or other prominent warning device ) on an energy isolating device to indicate that the energy isolating device and the equipment being controlled, may not be operated. o The tagout device shall be non-reusable, attached by hand, self-locking and non-releasing with a minimum unlocking strength of no less than 50 pounds, must be equivalent to an all environment tolerant nylon cable tie.

April 13, 2011 A STAR YALE UNIVERSITY SCIENCE STUDENT WAS KILLED EARLY TODAY IN AN INDUSTRIAL ACCIDENT AT A CAMPUS MACHINE SHOP WHERE EQUIPMENT FOR EXPERIMENTS WAS CONSTRUCTED.

Yale Vice President Linda Koch said the student, Michele Dufault of Scituate, Mass., died after a "terrible accident involving a piece of equipment in the student machine shop." Sources told the New Haven Register that the student's hair got caught in a spinning lathe and it pulled her in. The university said in a statement that the accident occurred at the Sterling Chemistry Laboratory, but provided no details of what happened. Dufault was an astronomy and physics major who was expected to graduate with a bachelor's of science degree this spring.

David Johnson, the machine shop instructor, could not be reached for comment. Yale's chemistry department online says it has a state-of-the-art machine shop to allow students to construct or modify research instrumentation. Access is strictly limited to those who have completed the shop course. The laboratory was closed today, with all classes and labs in the building cancelled.

"By all reports, Michele was an exceptional young woman, an outstanding student and young scientist, a dear friend and a vibrant member of this community. We will find ways in the next day to gather to celebrate her life and grieve this loss," Koch said.

A federal official says a Yale University student Michele Dufault died after her hair was pulled into a piece of equipment in a chemistry lab

machine shop.

Dufault's uncle, Frederick Dufault, said he spoke with her parents this morning and they were heading to the university. He did not have any information on her funeral arrangements.

She was an exceptional student and a wonderful person, just the best kid in the world. The world is going to be sadder place without her. I'm just still in shock," Frederick Dufault said. "She was gifted in many areas not just science, she was a gifted musician, she was a gifted athlete and did crew, she was just a super talented kid just beyond belief, it's a loss not only for her family but for the world." Dufault was a member of the "Yale Drop Team," an organization that allows students to perform reduced-gravity experiments with NASA programs. Dufault was a summer 2010 student fellow for the Woods Hole Oceanographic Institute in Woods Hole, Mass. Dean of academic programs, Jim Yoder said she participated in a highly selective program for young scientists.

"She worked closely with WHOI scientists who design and operate robotic vehicles to make remote chemical and other measurements in the ocean. The WHOI community is deeply saddened by the loss of such an intelligent young woman with such high potential," Yoder said.

In February 2009, Dufault participated in a workshop to engage young girls to become interested in science. Dufault told the Yale Daily News: "It's nice for the girls to be able to ask questions and say what they want without being judged by guys," Dufault said. "Almost all of the volunteers and scientists involved with this program are women—showing the girls that women can succeed in the sciences. I wish I had that opportunity at their age." Dufault attended high school at the Noble and Greenough School in Dedham, Mass. The head of school, Robert Henderson Jr. said her successes touched almost every aspect of the school's program.

"Dufault was an extraordinary young woman, one of the most precocious students who her teachers ever encountered," said Henderson. "She was simply brilliant. Her mind, her sense of curiosity, her perceptiveness, her sensitivity, and her enjoyment of what she did were extraordinary. She was a true intellectual."

*  BE AWARE OF THE DANGERS OF THE MACHINE YOU ARE OPERATING  USE ALL REQUIRED SAFETY EQUIPMENT  ENSURE GUARDS ARE IN PLACE AND FUNCTIONAL AT ALL TIMES  HAVE A PRE-OPERATIONAL CHECKLIST FOR EQUIPMENT’S SAFETY FEATURES   FOLLOW ALL SAFETY REQUIREMENTS IN PLACE IN THE SHOP YOU ARE WORKING IN. DO NOT USE AN IPOD TO MUSIC WHILE OPERATING MACHINERY