Last Updated: 02/28/2018
The purpose of the Injury Illness Prevention Program (IIPP) is to outline Cal Maritime's environmental health and safety requirements, expectations, and responsibilities in order to achieve effective campus safety performance through Integrated Safety Management (ISM). The Machine Guarding Safety Plan is a subject specific component the supports the overall University IIPP.
Note: Training Ship Golden Bear (TSGB) is regulated under MARAD. For operations pertaining to the TSGB - Refer to Shoreside Administration Manual (SAM) and Vessel Operations Manual (VOM).
Working with compressed gases and compressed gas systems.
Main Hazard(s), this is a list of all the hazards that were foreseen as far as is reasonably practicable. This risk assessment is to be used as a guide, only. Each person is responsible for investigating thoroughly and ensuring their working practices are safe, as well as reviewing their working practices regularly, in-line with national rules and guidelines.
Different types of mechanical actions are found, in varying combinations, on nearly every machine. Recognizing these hazards is the first step toward protecting workers.
Cutting action may involve rotating, reciprocating, or transverse motion. The danger of cutting action exists at the point of operation where finger, arm and body injuries can occur and where flying chips or scrap material can strike the head, particularly in the area of the eyes or face. Such hazards are present at the point of operation in cutting wood, metal, and other materials. Examples of mechanisms involving cutting hazards include band saws, circular saws, boring and drilling machines, turning machines, lathes, or milling machines.
Punching action results when power is applied to a slide (ram) for the purpose of blanking, drawing, or stamping metal or other materials. The danger of this type of action occurs at the point of operation where stock is inserted, held, and withdrawn by hand. Typical machines used for punching operations are power presses and iron workers.
Bending action results when power is applied to a slide in order to draw or stamp metal or other materials. A hazard occurs at the point of operation where stock is inserted, held, and withdrawn. Equipment that uses bending action includes power presses, press brakes, and tubing benders.
Shearing action involves applying power to a slide or knife in order to trim or shear metal or other materials. A hazard occurs at the point of operation where stock is physically inserted, held, and withdrawn. Examples of machines used for shearing operations are mechanically, hydraulically, or pneumatically powered shears.
There can be many other parts or machine components that present a hazard to the operator and surrounding personnel. Any part that could suddenly or unexpectedly move and injure a worker, or energy source that powers that part, should be safeguarded. Examples of these are:
Through implementation of this program, Cal Maritime Departments are responsible for assigning and training personnel to ensure that machines and equipment are properly guarded and designed to "fail safe" ensuring maximum safety for machine operators and nearby personnel. In addition, equipment found to be deficient must be removed from service until machine guards and/or safeguards can be implemented to ensure safety while operating or maintaining the equipment. To do this, assigned personnel must be trained as outlined in this program, and conduct safeguarding assessments.
One or more methods of physical machine-guarding must be provided to protect the operator and other personnel in the machine area from hazards such as the point of operation, the power transmission device, and other hazardous motions and actions. Any machine part, function, or process that may cause injury must be guarded. All machine-guards must be appropriate for the hazard involved, secured in place, constructed of substantial material and have surfaces free of hazardous projections.
Physical machine guards must protect personnel from mechanical, electrical, pneumatic, thermal and other hazards. To do so, these machine guards must:
Machine safeguarding needs widely differ due to varying physical characteristics, work- environments and operator involvement. Regardless of whether a process is manual or automated, any hazardous movement or other equipment process which poses a risk to personnel must be guarded as follows:
Point of Operation
The point of operation is the location where material is positioned, inserted, or manipulated, or where work such as shearing, punching, shaping, cutting, boring, forming, or assembling is being performed on the stock material. Milling machines, power presses, CNC turning machines, jointers, power saws, hand tools, guillotine cutters, and shears are all examples of machines that require point of operation guards.
Power Transmission Apparatus.
Power transmission apparatus are all components of the mechanical system which transmit energy from the motor to the location and part of the machine performing the work. These components include flywheels, pulleys, belts, connecting rods, couplings, cams, spindles, chains, crank, and gears.
Other Machine Hazards and Utilities
Auxiliary parts of a machine and any part that moves while the machine is working must be guarded to prevent accidental contact. Electrical hazards must be isolated inside solid-walled or flexible metal conduits to prevent contact with electrical conductors.
Hydraulic hazards (including pump and motor noise) must be isolated inside solid- walled isolation guards / containers, reinforced high-pressure piping, moving-actuators guarded, etc. Pneumatic hazards must be isolated inside solid-walled or flexible conduit to prevent impact / damage to compressed air piping, muffled exhaust noise, etc…
Different types of mechanical motions are found on nearly every machine in various combinations. Recognizing these hazards is the first step toward protecting workers.
Rotating motion is very dangerous. Even smooth, slowly rotating shafts can grip hair and clothing, pulling a worker into a hazardous position. Common rotating mechanisms are: collars, couplings, cams, clutches, flywheels, shaft ends, spindles, meshing gears, and horizontal or vertical shafting. Projections (such as set screws and bolts) or nicks and abrasions exposed on rotating parts increases the hazard.
In-running nip points
In-running nip point hazards are caused by the rotating parts on machinery. Parts can rotate in opposite directions while their axes are parallel to each other. These parts may be in contact or in close proximity. For example, stock fed between two rolls produces a nip point. Nip points are also created between rotating and tangentially moving parts. Some examples would be: the point of contact between two gears, a power transmission belt and its pulley, a chain and a sprocket, and a rack and pinion gear set.
Can occur between rotating and nearby fixed parts which create a shearing, crushing, or abrading action, such as a flywheel and nearby structural support, a screw conveyor and the conveyor-housing, or an abrasive grinding wheel and an incorrectly adjusted work rest and tongue.
Reciprocating motions may be hazardous because, during the back- and-forth or up-and-down motion, a worker may be struck by or caught between a moving and a stationary part.
Transverse motion (movement in straight, continuous line) creates a hazard because a worker may be struck or caught in a pinch or shear point by the moving part in relation to a nearby fixed object.
There are four general types of guards: fixed, interlocked, adjustable, and self-adjusting.
As its name implies, a fixed guard is a permanent part of the machine. It is not dependent upon moving parts to function. This guard is usually preferable to all other types. Fixed guards can be constructed to suit many specific applications and provides maximum protection to operators, while requiring minimum maintenance. One limitation of a fixed guard is that it may interfere with visibility. Also, adjustments and repairs to the machine often require its removal, thereby necessitating other means of protection for maintenance personnel.
Interlocked Guards and Latch Control Circuits
When an interlocked guard is opened or removed, the tripping mechanism or power automatically shuts off or disengages, and the machine cannot cycle or be started until the guard is back in place. An interlocked guard may operate on electrical, mechanical, hydraulic, or pneumatic power or any combination of these. To be most effective, all removable guards should be interlocked to prevent occupational hazards.
Interlocks should be designed to discourage the capability to easily bypass the interlock with readily available items such as tape, pieces of metal, screws, tools, etc. Some interlock devices use special keys, trapped keys or actuators that make the interlock more difficult to bypass. There are also interlocking devices that physically obstruct or shield the interlock with the guard open, and others that use electrical, mechanical, magnetic, or optical coding.
Replacing the guard should not automatically restart the machine.
When an interlock is triggered and a machine shuts down, the machine must not be able to be restarted simply by repairing / restoring the interlock or guard. Interlocks must be wired through a utility-power "Latch Control Circuit" that "drops out" when any of the interlocks are triggered. The "Latch Control Circuit" shuts off the main control power or in some other way stops the equipment in a "fail safe" condition. When all interlocks are restored so that the machine can safely restart, the "Latch Control Circuit" now can allow the machine to be restarted. But, the equipment operator must go through the normal "start- up" procedures in order for the equipment to safely restart.
Adjustable guards are useful because they allow flexibility in accommodating various sizes of stock. They provide a barrier that may be adjusted to facilitate a variety of production operations; however, because they are adjustable, they are subject to human error and being "out of adjustment" at any given time.
The openings of the guard-barrier is determined by the movement of the stock or by automatic adjustment based upon machine motion / position. As the operator engages the machine's point of operation with the stock, the guard is automatically pushed away providing an opening which is only large enough to admit the stock into the point- of-operation. After the stock is removed, the guard returns to the safe-position. This guard protects the operator by placing a barrier between the danger area and the operator. Self-adjusting guards offer different degrees of protection. Off-the-shelf guards are often commercially available, but they don't always provide maximum protection. A common example of this kind of guard is a hand-held circular saw blade guard that adjusts exposing the blade as the cut is made by the operator.
Guards must be constructed of substantial material so they can withstand the vibration, shock, and wear to which they will be subjected during normal operation. Guards are usually constructed of metal, impact-resistant plastic, woven wire mesh, or wood (good for corrosive environments). One type of material is not necessarily superior to the other, as long as it meets the performance objective of the guard.
To be effective, they must safeguard the operator and nearby personnel while allowing the work to continue with minimal disruption to the machine's process. Guards should be hinged or have sliding or removable sections to allow for the admission of oil and lubricants, change belts, and to make adjustments. Guards should be affixed to the machine where possible and secured elsewhere if for any reason attachment to the machine is not possible.
A machine guard should not have any shear points, sharp edges, or unfinished surfaces which could cause lacerations. If a machine guard creates a new hazard, it defeats its own purpose.
Manufacturers of many single-purpose machines provide point-of-operation and power- transmission safeguards as standard equipment. Unfortunately, not all machines in use have built-in safeguards provided by the manufacturer, and many older machines were built without being fully guarded. In these cases, it is necessary to purchase aftermarket guards or fabricate them.
The tables that follow discuss the advantages and disadvantages of both manufacturer built and user-built guards.
Guards Designed and Built by The Manufacturer
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Guards Fabricated by The Machine Owner / User
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A safeguarding device or control works by keeping the operator's hands and body outside of the danger zone or by stopping the machine if the operator's hands or body enter the danger zone.
Barriers and Gates
A barrier is a device or object that provides a physical boundary to the hazard. Barrier devices are designed and constructed to enclose the hazard zone prior to the start of the hazardous portion of the machine cycle. They are held closed until completion of the cycle or until the machine has ceased motion.
Gates are movable barriers that protect the operator at the point of operation before the machine cycle can be started. Gates are usually interlocked and, in many instances, designed to be operated with each machine cycle. If the gate does not fully close, the machine will not function
An optical presence-sensing device uses a system of light beams or curtains that can interrupt the machine's operating cycle. If the sensing field is broken, the machine stops and will not cycle. This device must be used only on machines that can be stopped before the worker can reach into the danger area.
An electromechanical presence-sensing device has a probe or contact bar that descends to a predetermined distance when the operator initiates the machine cycle. If there is an obstruction preventing it from descending its full pre-determined distance, the machine will not cycle.
When depressed, a pressure-sensitive device will deactivate the machine. Examples of pressure–sensitive devices are body bars, bump or contact strips, or mats.
A pullback device is designed to protect the machine operator by keeping the operator's hands out of the danger zone during the hazardous portion of the machine cycle. It utilizes a series of cables attached to the operator's hands, wrists, or arms which physically withdraws them before a cycle.
The restraint device protects the operator by physically holding the operator's hands away from the hazard zone at all times. This is usually accomplished by the use of wrist straps.
Physical Restraint Device
Both pullback and restraint devices are adjustable and therefore subject to human error.
A two-hand control requires constant, concurrent pressure to activate the machine. The operator's hands are required to be at a safe location (on control buttons) and at a safe distance from the danger area while the machine completes its closing cycle.
A two-hand trip requires concurrent application of both of the operator's control buttons to activate the machine cycle, after which the hands are free. This device is used with machines equipped with full-revolution clutches. The trips must be placed far enough from the point of operation to make it impossible for the operators to move their hands from the trip buttons or handles into the point of operation before the first half of the cycle is completed to prevent them from being accidentally placed in the danger area prior to the slide/ram or blade reaching the full "down" position.
The following safeguards and methods may be used in conjunction with primary machine guarding devices and controls to reduce the risk or create awareness of a hazard. Although these aids do not give complete protection from machine hazards, they may provide the operator with an extra margin of safety. Most designs / techniques for safeguarding machines focus on mechanical motion; however, machines create many non-mechanical hazards which should be protected against as well.
Access to Machinery
Machines must be designed and constructed in a way that allows all necessary tasks to be carried out, but provides an acceptable level of protection for surrounding personnel. When feasible, access to hazardous machinery should be restricted to authorized personnel only. This can be accomplished by locating the machines and equipment in a separate room accessible only by key or keycard. Another option would be establishing a one-way traffic flow where users pass a check-in desk. Access may also include restrictions to certain hours and dates, although this is impossible to accomplish with a mechanical lock and key.
Anchoring Fixed Machinery
A machine designed for a fixed location must be securely anchored to a building's structure to prevent walking or moving.
Awareness Barriers and Signals
Awareness barriers do not provide physical protection but serve as reminders to persons that they are approaching the danger area. An awareness barrier may move or be adjusted to allow entry of work pieces and personnel, but prevents anyone from reaching the hazard without awareness. In addition, it provides visual boundaries and indicates the hazard zone.
Awareness signals provide a recognizable audible or visual signal of an approaching or present hazard. Indicator lamps, usually white, red and green, may be provided to indicate that the device is functioning. Indicator lights should be labeled or have distinct patterning or flashing.
Audible awareness signals, like annunciators or bells, should have a distinctive sound and intensity such that they will be distinguished from the highest ambient noise level in the hazard zone.
Control systems must be designed to enable the operator to interact safely with the machine. Ideally, a machine will have separate control zones for start-up functions, emergency stopping, stopping as a result of a safeguard device, and isolation or energy dissipation.
Each control must require a deliberate action to initiate operation. In addition, controls must be:
Emergency Stop Devices
All machines must be equipped with adequate means whereby the operator of the machine or other person can disconnect the power promptly in case of emergency. If the machine's power switch is not located near the operator/point of operations, an emergency stop device must be provided that will immediately cut power to the equipment and cause motion or other operations to cease.
Exception: The only exception to this rule is in the case of robotic control where power-disconnection could cause the robot to physically collapse under the force of gravity potentially causing injury. In such situations, the emergency stop may cause the robot to "freeze" motion but not remove power from its servo-motor controls.
Emergency stop devices must be continuously operable, clearly identified, clearly visible and readily accessible.
The device must be actuated by a single human action and initiate an immediate stop command. The emergency stop command must override all other functions and operations in all modes for hazardous motion. These devices must be manually reset to restart the machine. Examples of emergency stop devices are:
All emergency stop devices must be colored red. The background immediately around devices and disconnect switch actuators used as emergency stop devices must be colored yellow. The red/yellow combination is reserved exclusively for the emergency stop and emergency switching off applications.
Energy Isolation – Lockout Tagout (LOTO)
When operators are required to place any part of their body into a hazardous zone, procedures for shutdown, energy isolation, and lock-out/block-out/tag-out must be established and followed.
The process for safely controlling or dissipating hazardous stored energy must be identified for all machines as part of their design / installation for easy Energy Isolation – Lockout /Tagout. When servicing or adjustment operations must be performed with the power on and safe-guards removed (i.e., fine adjustments, testing and identifying the source of a problem), separate procedures must be developed to protect personnel during these situations.
Refer to Cal Maritime's SRM Energy Isolation – Lockout/Tagout (LOTO) Program (available on the SRM website) for details on how to conduct LOTO and design / develop equipment for ease of LOTO application.
Energy Source / Utility Interruption
Machinery must be designed to prevent hazardous conditions resulting from interruption or excessive fluctuation of any energy source or utility used by the machine to maintain safe operation. In the event of loss of energy / utility, all devices whose permanent operation is required for safety (e.g., locking, clamping devices, cooling or heating devices, braking) must operate to maintain safety even with the utilities removed.
Fail-Safe Design is the design of interlocks and machine-control-logic wiring and programming to ensure the safety of the operator, personnel nearby and machine processes. A fail-safe system should be designed to default to its safest state of being in the event of any kind of "out-of-normal" failure condition, such as utility, wiring or component failures. The design assumption is that failure will eventually occur but when it does, it will fail in a manner as to mitigate injuries and losses.
Feeding and Ejection Methods
Many feeding and ejection methods do not require operators to place their hands in the danger area. In some cases, no operator involvement is necessary after the machine is set up. In other situations, operators can manually feed the stock with the assistance of a feeding mechanism. Properly designed ejection methods do not require operator involvement after the machine starts to function. Using feeding and ejection methods does not eliminate the need for safeguarding. Guards and other devices must be used wherever they are necessary to provide protection from hazards. Feeding and ejection methods can be automatic or semiautomatic.
Hand-Feeding and Retrieval Tools
Hand-feeding and retrieval tools can place or remove stock. Hand-feeding tools are intended for placing and removing materials into the in the danger area of a machine. Hand-feeding tools are not a point-of-operation guard or protection device and shall not be used in lieu of appropriate safeguards, but as a supplement. A typical use would be for reaching in the danger area of a press or press brake. Another example would be a push stick or block used when feeding stock into a saw blade. When it becomes necessary for hands to be in close proximity to the blade, the push stick or block may provide a few inches of safety and prevent a severe injury.
To consider a part of a machine to be safeguarded by location, the dangerous moving part of a machine must be located in areas that are not accessible to operators or personnel and do not present a hazard during the normal operation of the machine.
This may be accomplished by using enclosure walls or fences. Another possible solution is to have dangerous parts located high enough to be out of the normal reach of any worker. Locating a machine in a separate and restricted access area may qualify as guarding by location.
Shields can protect workers from flying particles, chips, sparks, and oils, but do not provide protection from machine hazards. Shields must not interfere with the workers ability to operate the machine or reduce the operator's field of vision.
Users of Machines with Safe-Guards
Users of machines that are provided with guards / interlocks by their manufacturer must:
The checklist in this program and SRM can assist in determining the need for machine guards or other safeguarding methods.
When conducting a machine guarding assessment, it is imperative to analyze all potential hazards associated with normal operating procedures: start-up, shutdown, setup, inspection, servicing, maintenance and lockout/tagout. It is also important to consider unusual operations, equipment malfunction, broken tooling, and foreseeable misuse of the equipment.
Similar machines may be used as a starting point when tasks and hazards are comparable. Using this information does not eliminate the need to follow a risk assessment process for the specific conditions of use. For example, when a shear used for cutting plastic is compared with a shear used for cutting metal, the risks associated with the different materials should be assessed.
The extent of safeguarding needs can vary based on numerous factors, such as degree of exposure and the potential for harm. The necessity for guarding equipment used by inexperienced operators exceeds what would typically be required in a professional shop. A basic risk assessment can assist with determining this extent.
The assessment should be conducted using logical deduction and a qualitative assessment of the following:
Color-coding certain parts of a machine will make the employee aware of potentially hazardous conditions. Orange should be used to identify hazardous parts of the machines, such as exposed edges, pulleys, gears, rollers, cutting devices, power jaws, etc. Yellow should be used to identify physical hazards such as striking against, stumbling, falling, and caught in- between.
Warnings, stickers, labels and safety reminders should be affixed to highlight the dangerous areas.
Equipment-specific operating procedures should be established and posted on/near each machine. If possible, have the equipment's operating manual available to workers
Cal Maritime and its subcontractors shall comply with the following requirements.
In case of conflict or overlap of the below references, the most stringent provision shall apply.