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Subchapter 7. General Industry Safety Orders
Group 8. Points of Operation and Other Hazardous Parts of Machinery 
 Article 54. Scope and General Definitions 
  
§4188. Definitions. 
 
Classes. The designation “Class-A” with an order means that the rule   applies for all kinds of work. The designation “Class-B” means that the order   applies unless the nature of the work, type of machinery, or size and shape of   material being worked will not permit.
Danger Zone. Any place in or about a machine or piece of equipment where an   employee may be struck by or caught between moving parts, caught between moving   and stationary objects or parts of the machine, caught between the material and   a moving part of the machine, burned by hot surfaces or exposed to electric   shock.
Interlock. A device that operates to prevent the operation of a machine   while the cover or door of the machine is open or unlocked, and which will also   hold the cover or door closed and locked while the machine is in   motion.
Point of Operation. That part of a machine which performs an operation on   the stock or material and/or that point or location where stock or material is   fed to the machine. A machine may have more than one point of   operation.
(b) Specific Definitions for Power Operated Presses. Adjustable Barrier   Guard. A barrier requiring adjustment for each job or die setup.
Antirepeat. The part of the clutch/brake control system designed to limit   the press to a single stroke if the operating means is held operated. Antirepeat   requires release of all tripping mechanisms before another stroke can be   initiated. “Antirepeat” is also called single stroke reset or reset   circuit.
Brake. The mechanism used on a mechanical power press to stop and/or hold   the crankshaft, either directly or through a gear train, when the clutch is   disengaged.
Brake Monitor. A sensor designed, constructed, and arranged to monitor the   effectiveness of the press braking system.
Bolster Plate. The plate attached to the top of the bed of the press having   drilled holes or T-slots for attaching the lower die or die shoe.
Certification or Certify. In the case of design certification/validation   that the manufacturer has reviewed and tested the design and manufacture, and in   the case of installation certification/validation and annual   recertification/revalidation that the employer has reviewed and tested the   installation, and concludes in both cases that the requirements of sections 4192   through 4211 and Appendix A have been met. The certifications are made to the   validation organization.
Certification/Validation and Certify/Validate. The combined processes of   certification and validation.
Clutch. The coupling mechanism used on a mechanical power press to couple   the flywheel to the crankshaft, either directly or through a gear   train.
(1) Full Revolution Clutch. A type of clutch   that, when tripped, cannot be disengaged until the crankshaft has completed a   full revolution and the press slide a full stroke. 
(2) Part Revolution Clutch. A type of clutch that   can be disengaged at any point before the crankshaft has completed a full   revolution and the press slide a full stroke. 
Concurrent. Acting in conjunction, and is used to   describe a situation wherein two or more controls exist in an operated condition   at the same time. 
Control System. Sensors, manual input and mode   selection elements, interlocking and decision-making circuitry, and output   elements to the press operating mechanism. 
Continuous. Uninterrupted multiple strokes of the   slide without intervening stops (or other clutch control action) at the end of   individual strokes. 
Counter-balance. The mechanism that is used to   balance or support the weight of the connecting rods, slide, and slide   attachments. 
Device. A press control or attachment that: 
(A) Restrains the operator from inadvertently   reaching into the point of operation, or 
(B) Prevents normal press operation if the   operator's hands are within the point of operation as the dies close. 
(C) Automatically withdraws the operator's hands   if the operator's hands are within the point of operation as the dies close, or 
(D) Prevents the initiation of a stroke, or stops   stroke in progress, when there is an intrusion through the sensing field by any   part of the operator's body or by any other object, or 
(E) Locating single cycle operating controls so   that the slide completes its downward travel or stops the ram motion before the   operator's hands can reach into the point of operation. 
Combined Stroking-Control Systems. Combined   stroking-control systems are two independent control systems on the same   machine, only one of which is used at a time. 
Die. The tooling used in a press for cutting or   forming material. An upper and a lower die make a complete set. 
Die Builder. Any person who builds dies for power   presses. 
Die Set. A tool holder held in alignment by guide   posts and bushings and consisting of a lower shoe, an upper shoe or punch   holder, and guide posts and bushings. 
Die Setter. An individual who places or removes   dies in or from mechanical power presses, and who, as a part of his duties,   makes the necessary adjustments to cause the tooling to function properly and   safely. 
Die Setting. The process of placing or removing   dies in or from a power press, and the process of adjusting the dies, other   tooling and safeguarding means to cause them to function properly and safely. 
Die Shoe. A plate or block upon which a die   holder is mounted. A die shoe functions primarily as a base for the complete die   assembly, and, when used, is bolted or clamped to the bolster plate or the face   of slide. 
Direct Drive. The type of driving arrangement   wherein no clutch is used; coupling and decoupling of the driving torque is   accomplished by energization and de-energization of a motor. Even though not   employing a clutch, direct drives match the operational characteristics of “part   revolution clutches” because the driving power may be disengaged during the   stroke of the press. 
Division-Recognized Third Party Validation   Organization. An independent third-party validation organization which has been   recognized by the U.S. Labor Department, Occupational Safety and Health   Administration (OSHA) in accordance with the requirements specified in Appendix   C of paragraph (h), 29 CFR 1910.217, revised March 14, 1988 which is   hereby incorporated by reference. 
Ejector. A mechanism for removing work or   material from between the dies. 
Face of Slide. The bottom surface of the slide to   which the punch or upper die is generally attached. 
Feeding. The process of placing or removing   material within or from the point of operation. 
Foot Control. The foot operated control mechanism   designed to be used with a clutch or clutch/brake control system. 
Foot, Kick, and Hand Presses. Machines actuated   by foot or hand power only, and fitted with rams or dies for the purposes of   blanking, trimming, drawing, punching or stamping, forming or assembling cold   material. 
Foot Pedal. The foot operated lever designed to   operate the mechanical linkage that engages the clutch and/or disengages the   brake. 
Gate or Movable Barrier Device. A movable barrier   arranged to enclose the point of operation before the press stroke can be   started. 
Guide Post. The pin attached to the upper or   lower die shoe, operating within the bushing on the opposing die shoe, to   maintain the alignment of the upper and lower dies. 
Hand Feeding Tool. Any hand-held tool designed   for placing or removing material or parts to be processed within or from the   point of operation. 
Holdout or Restraint Device. A mechanism,   including attachments for operator's hands, that when anchored and adjusted,   prevent the operator's hands from entering the point of operation. 
Inch. An intermittent motion imparted to the   slide (on machines using part revolution clutches) by momentary operation of the   “Inch” operating means. Operation of the “Inch” operating means engages the   driving clutch so that a small portion of one stroke or indefinite stroking can   occur, depending upon the length of time the “Inch” operating means is held   operated. “Inch” is a function used by the die setter for setup of dies and   tooling, but is not intended for use during production operations by the   operator. 
Jog. An intermittent motion imparted to the slide   by momentary operation of the drive motor, after the clutch is engaged with the   flywheel at rest. 
Knockout. A mechanism for releasing material from   either die. 
Liftout. The mechanism also known as knockout. 
Manual Feeding. Feeding wherein the material or   part being processed is handled by the operator on each stroke of the press. 
Operator's Station. The complete complement of   controls used by or available to an operator on a given operation for stroking   the press. 
Pinch Point. Any point other than the point of   operation at which it is possible for a part of the body to be caught between   the moving parts of a press or auxiliary equipment, or between moving and   stationary parts of a press or auxiliary equipment or between the material and   moving part or parts of the press or auxiliary equipment. 
Point of Operation. (See section 4188(a).) 
Power Operated Presses. For the purposes of   Article 55, power operated presses include all mechanically powered machines   that shear, punch, form, or assemble metal or other materials by means of tools   or dies attached to or actuated by slides, commonly referred to as mechanical   power presses (punch presses), press brakes, hydraulic power presses (punch   presses), and rivet setting machines. 
Power Press, Hydraulic (Punch Press). A machine   which is hydraulically powered that shears, punches, forms, draws, or assembles   metal or other material by means of tools attached to or actuated by slides. 
Power Press, Mechanical (Punch Press). A   mechanically powered machine that shears, punches, forms or assembles metal or   other material by means of cutting, shaping, or combination dies attached to or   actuated by slides. 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 definite path by the frame of the   press. 
Power Press, Pneumatic. A machine which derives   its primary mechanical action (i.e. shearing, punching, bending, forming,   drawing, extruding, assembly or other action) from a pneumatic energy source   (i.e. pneumatically driven ram). A fully pneumatic power press differs from a   mechanical or hydraulic press which may utilize pneumatic systems to only   activate a brake/clutch, slide counterbalance or other system but which uses   mechanical means or hydraulic fluid to power the ram. 
Presence Sensing Device. A device designed,   constructed and arranged to create a sensing field or area that signals the   clutch/brake control to deactivate the clutch and activate the brake of the   press when any part of the operator's body or a hand tool is within such field   or area. 
Presence Sensing Device Initiation. An operating   mode of indirect manual initiation of a single stroke by a presence sensing   device when it senses that work motions of the operator, related to feeding   and/or removing parts, are completed and all parts of the operator's body or   hand tools are safely clear of the point of operation. 
Press Brake Die, General-Purpose. A die set used   to perform common bending and forming operations on a variety of piece parts or   products and not designed for a unique or unusual part or product. 
Press Brake, General-Purpose. A mechanically or   hydraulically operated machine having only one operator at the front of the   machine and with a single operating foot control device which permits the   operator to exercise full and final control over the movement of the ram. 
Press Brake, Special-Purpose. A machine that can   be mechanically or hydraulically operated by one or more operators from the   front of the machine, each provided with an operating control station.   Concurrent operation of each station being used is required to place the ram in   motion. 
Ram. See definition for Slide. 
Repeat. An unintended or unexpected successive   stroke of the press resulting from a malfunction. 
Rivet Setting Equipment. Powered machines   designed to insert and clinch fasteners commonly called rivets. 
Safety Block. A prop that, when inserted between   the upper and lower dies or between the bolster plate and the face of the slide,   prevents the slide from falling of its own deadweight. 
Safety System. The integrated total system,   including the pertinent elements of the press; the controls; the safeguarding,   any required supplemental safeguarding, and their interfaces with the operator;   and the environment designed, constructed and arranged to operate together as a   unit, such that a single failure or single operating error will not cause injury   to personnel due to point of operation hazards. 
Setting up Operations. Operations in which   fixtures or tooling which support, secure, or act upon the workpiece are mounted   on the machine surfaces or in machine components designed to accept such   tooling. 
Single Stroke. One complete stroke of the slide,   usually initiated from a full open (or up) position. 
Single Stroke Control. An arrangement used to   limit the travel of the slide to one complete stroke at each engagement of the   clutch. 
Slide. A reciprocating part of the machine or   press. It is also referred to as a ram, plunger, platen, or mandrel. 
Stop Control. An operator control designed to   immediately deactivate the clutch control and activate the brake to stop slide   motion. 
Stripper. A mechanism or die part for removing   the parts of material from the punch. 
Stroking Selector. The part of the clutch/brake   control that determines the type of stroking when the operating means is   actuated. The stroking selector generally includes positions for “Off” (Clutch   Control), “Inch,” “Single Stroke,” and “Continuous” (when continuous is   furnished). 
Trip or (tripping). Activation of the clutch to   “run” the press. 
Turnover Bar. A bar used in die setting to   manually turn the crankshaft of the press. 
Unitized Tooling. A type of die in which the   upper and lower members are incorporated into a self-contained unit so arranged   as to hold the die members in alignment. 
Validation or Validate. For PSDI safety systems   that a Division-recognized third-party validation organization: 
(A) For design certification/validation has   reviewed the manufacturer's certification that the PSDI safety system meets the   requirements of sections 4192 through 4211 and Appendix A and the underlying   tests and analyses performed by the manufacturer, has performed additional tests   and analyses which may be required by sections 4192 through 4211 and Appendix A,   and concludes that the requirements of sections 4192 through 4211 and Appendix A   have been met; and 
(B) For installation certification/validation and   annual recertification/revalidation has reviewed the employer's certification   that the PSDI safety system meets the requirements of sections 4192 through 4211   and Appendix A and the underlying tests performed by the employer, has performed   additional tests and analyses which may be required by sections 4192 through   4211 and Appendix A, and concludes that the requirements of sections 4192   through 4211 and Appendix A have been met. 
Note: Authority cited: Section 142.3, Labor   Code. Reference: Section 142.3, Labor Code. 
HISTORY 
1. Renumbering from section 4187 filed 10-25-74; effective thirtieth day   thereafter (Register 74, No. 43).
2. New subsection (3) and renumbering of subsection (3) to (4) filed   7-17-75; effective thirtieth day thereafter (Register 75, No. 29).
3. Amendment filed 11-17-82; effective thirtieth day thereafter (Register   82, No. 47).
4. Amendment filed 12-12-84; effective thirtieth day thereafter (Register   84, No. 50).
5. Amendment filed 10-31-85; effective thirtieth day thereafter (Register   85, No. 44).
6. Amendment of subsection (b) filed 4-20-90; operative 5-20-90 (Register   90, No. 20).
7. Editorial correction of printing error inadvertently omitting text   (Register 90, No. 44).
8. Editorial correction amending definition of Combined Stroking-Control   Systems and reinserting definitions of Division-Recognized Third Party   Validation Organization and Presence Sensing Device (Register 92, No.   33).
9. New definition of “Power Press, Pneumatic” filed 5-8-96; operative   6-7-96 (Register 96, No. 19).
10. Amendment of definitions of “Power Operated Presses,” “Power Press,   Hydraulic (Punch Press),” “Power Press, Mechanical (Punch Press)” and “Ram” and   new definition of “Slide” filed 5-7-2001; operative 6-6-2001 (Register 2001, No.   19).
11. Amendment adding definition of “Press Brake Die, General-Purpose” filed   1-5-2012; operative 2-4-2012 (Register 2012, No. 1).
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