(7-1-97)

o. Device means a press control or attachment that: restrains the operator from inadvertently reaching into the point of operation; prevents normal press operation if the operator's hands are inadvertently within the point of operation; or automatically withdraws the operator's hands if the operator's hands are inadvertently within the point of operation as the dies close. (7-1-97)

p. Die is the tooling used in a press for cutting or forming material. An upper and a lower die make a complete set. (7-1-97)

q. Die Builder is any person who builds die for power presses. (7-1-97)

r. Die Enclosure Guard is an enclosure attached to the die shoe or stipper, or both, in a fixed position. (7-1-97)

s. Die Set is 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. (7-1-97)

t. Die Setter is 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. (7-1-97)

u. Die Setting is the process of placing or removing dies in or from a mechanical power press, and the process of adjusting the dies, other tooling and safeguarding means to cause them to function properly and safely. (7-1-97)

v. Die Shoe is 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. (7-1-97)

w. Direct Drive is the type of driving arrangement wherein no clutch is used; coupling and decoupling of the driving torque is accomplished by energization and deenergization 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. (7-1-97)

x. Ejector is a mechanism for removing work or material from between the dies. (7-1-97)

y. Face of Slide is the bottom surface of the slide to which the punch or upper die is generally attached. (7-1-97)

z. Feeding is the process of placing or removing material within or from the point of operation. (7-1-97)

aa. Fixed Barrier Guard is a die space barrier attached to the press frame. (7-1-97)

bb. Flanges are collars, discs, or plates between which wheels are mounted and are referred to as adaptor, sleeve, or back up type. See sub-section 250.21 of this section for full description. (7-1-97)

cc. Foot Control is the foot operated control mechanism designed to be used with a clutch or clutch/brake control system. (7-1-97)

dd. Foot Pedal is the foot operated lever designed to operate the mechanical linkage that trips a full revolution clutch. (7-1-97)

ee. Full Revolution Clutch is 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. (7-1-97)

ff. Gate or Movable Barrier Device is a movable barrier arranged to enclose the point of operation before the press stroke can be started. (7-1-97)

gg. Guard is a barrier that prevents entry of the operator's hands or fingers into the point of operation. (7-1-97)

hh. Guide Post is 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. (7-1-97)

ii. Hand Feeding Tool is any hand held tool designed for placing or removing material or parts to be processed within or from the point of operation. (7-1-97)

jj. Holdout or Restraint Device is a mechanism, including attachments for operator's hands, that when anchored and adjusted prevent the operators hands from entering the point of operation. (7-1-97)

kk. Inch is 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 (1) 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. (7-1-97)

ll. Inorganic Wheels are wheels which are bonded by means of inorganic material such as clay, glass, porcelain, sodium silicate, magnesium oxychloride, or metal. Wheels bonded with clay, glass, porcelain, or related ceramic materials are characterized as "vitrified bonded wheels". (7-1-97)

mm. Interlocked Press Barrier Guard is a barrier attached to the press frame and interlocked so that the press stroke cannot be started normally unless the guard itself, or its hinged or movable sections, enclose the point of operation. (7-1-97)

nn. Job is an intermittent motion imparted to the slide by momentary operation of the drive motor, after the clutch is engaged with the flywheel at rest. (7-1-97)

oo. Knockout is a mechanism for releasing material from either die. (7-1-97)

pp. Liftout is the mechanism also known as knockout. (7-1-97)

qq. Manual Feeding is feeding wherein the material or part being processed is handled by the operator on each stroke of the press. (7-1-97)

rr. Off-Hand Grinding is the grinding of any material or part which is held in the operator's hand. (7-1-97)

ss. Operator's Station is the complete complement of controls used by or available to an operator on a given operation for stroking the press. (7-1-97)

tt. Organic Wheels are wheels which are bonded by means of an organic material such as resin, rubber, shellac, or other similar bonding agent. (7-1-97)

uu. Part Revolution Clutch is 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. (7-1-97)

vv. Point of Operation is the area on a machine where material is actually positioned and work is performed such as shearing, punching, forming, or assembly. (7-1-97)

ww. Presence Sensing Device is a device designed, constructed and arranged to create a sensing field or area and deactivate the clutch control of the press when an operator's hand and/or other parts of his body is within such field or area. (7-1-97)

xx. Press is a mechanically powered machine that shears, punches, forms, or assembles metal or other material by means of cutting, shaping, or combination dies attached to 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 by a definite path by the frame of the press. (7-1-97)

yy. Pull-Out Device is a mechanism attached to the operator's hands and connected to the upper die or slide of the press, that is designed, when properly adjusted, to withdraw the operator's hands as the dies closes, if the operator's hands are inadvertently within the point of operation. (7-1-97)

zz. Push Stock is a narrow strip of wood or other soft material with a notch cut into one end and which is used to push short pieces of material through saws. (7-1-97)

aaa. Repeat is an unintended or unexpected successive stroke of the press resulting from a malfunction. (7-1-97)

bbb. Safety block is 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 off by its own deadweight. (7-1-97)

ccc. Safety Guard is an enclosure designed to restrain the pieces of the grinding wheel and furnish all possible protection in the event that the wheel is broken while in operation. See sub-section 250.21 of this section. (7-1-97)

ddd. Semiautomatic Feeding is feeding wherein the material or part being processed is placed within or removed from the point of operation by an auxiliary means controlled by operator on each stroke of the press. (7-1-97)

eee. Single Stroke is one complete stroke of the slide, usually initiated from a full open (or up) position, followed by closing, (or down), and then a return to the full open position. (7-1-97)

fff. Slide is the main reciprocating press member. A slide is also called a ram, plunger, or platen. (7-1-97)

ggg. Snagging is grinding which removes relatively large amounts of material without regard to close tolerances or surface finish requirements. (7-1-97)

hhh. Stop Control is an operator control designed to immediately deactivate the clutch control and activate the brake to stop slide motion. (7-1-97)

iii. Stripper is a mechanism or die part for removing the parts or material from the punch. (7-1-97)

jjj. Stroking Selector is the part of the clutch/brake 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)). (7-1-97)

kkk. Surface Feet per Minute (s.f.p.m.) is the distance in feet any one abrasive grain on the peripheral surface of a grinding wheel travels in one (1) minute. EXAMPLES: twenty-four (24) inch diameter wheel, one-thousand (1,000) revolutions per minute. Surface feet per minute .262 x 24 x 1,000 = 6,288 s.f.p.m.12 - inch diameter wheel, 1,000 revolutions per minute. Surface feet per minute .262 x 12 x 1,000 = 3,144 s.f.p.m. (7-1-97)

lll. Sweep Device is a single or double arm (rod) attached to the upper die or slide of the press and designed to move the operator's hands to a safe position as the dies close, if the operator's hands are inadvertently within the point of operation. (7-1-97)

mmm. Terrazzo, Modified Types 6 and 11 Wheels are some type 6 and 11 cup wheels used in the terrazzo trade having tapered (K) dimensions to match a special tapered flange furnished by the machine builder. See Figure 250.02-A. Limitation: These wheels shall be mounted only with a special tapered flange. (7-1-97)

FIGURE 250.02-A

Typical examples of modified types 6 and 11 wheels (terrazzo) showing tapered (K) dimensions.

nnn. Trip or Tripping is the activation of the clutch to run a press. (7-1-97)

ooo. Turnover bar is a bar used in die setting to manually turn the crankshaft of the press. (7-1-97)

ppp. Two Hand Control Device is a two-hand trip that further requires concurrent pressure from both hands of the operator during a substantial part of the die-closing portion of the stroke of the press. (7-1-97)

qqq. Two (2) Hand Trip is a clutch actuating means, requiring the concurrent use of both hands of the operator to trip the press. (7-1-97)

rrr. Type 1 Straight Wheels are wheels having diameter, thickness, and hole size dimensions, and shall be used only on the periphery. Type 1 wheels shall be mounted between flanges. See Figure 250.02-B Limitation: Hole dimension (H) should not be greater than two-thirds of wheel diameter dimension (D) for precision, cylindrical, center less, or surface grinding applications. Maximum hole size for all other applications should not exceed one-half wheel diameter. (7-1-97)

FIGURE 250.02-B

sss. Type 2 Cylinder Wheels are wheels having diameter, wheel thickness, and rim thickness dimensions. Grinding is performed on the rim face only, dimension (W). Cylinder wheels may be plain, plate mounted, inserted nut, or of the projecting stud type. See Figure 250.02-C. Limitation: Rim height, (T) dimension, is generally equal to or greater than rim thickness, (W) dimension. (7-1-97)

FIGURE 250.02-C

ttt. Type 6 Straight Cup Wheels are wheels having diameter, thickness, hole size, rim thickness, and back thickness dimensions. Grinding is always performed on rim face, (W) dimension. See Figure 250.02-D. Limitation: Minimum back thickness, (E) dimension, should not be less than 1/4 (T) dimension. In addition, when un-threaded hole wheels are specified, the inside flat, (K) dimension, must be large enough to accommodate a suitable flange. (7-1-97)

FIGURE 250.02-D

uuu. Type 11 Flaring Cup Wheels means wheels having double diameter dimensions (D) and (J) and in addition, have thickness, hole size, rim and back thickness dimensions. Grinding is always performed on rim face, (W) dimension Type 11 wheels are subject to all limitation of use and mounting listed for type 6 straight sided cup wheels. See Figure 250.02-E. Limitation: Minimum back thickness, (E) dimension, should not be less than threaded hole wheels are specified the inside flat, (K) dimension, shall be large enough to accommodate a suitable flange. (7-1-97)

FIGURE 250.02-E

vvv. Types 27 and 28 Depressed Center Wheels are wheels having diameter, thickness, and hole size dimensions. Both types are reinforced, organic bonded wheels having offset hubs which permit side and peripheral grinding operations without interference with the mounting. Type 27 wheels are manufactured with flat grinding rims permitting notching and cutting operations. Type 28 wheels have saucer shaped grinding rims. Limitations: Special supporting, back adapter and inside flange nuts are required for the proper mounting of these types of wheels subject to limitations of sub-section 250.21.x through sub-section 250.21.cc. of this section. Mounts which are affixed to the wheel by the manufacturer may not require an inside nut and shall not be reused. (7-1-97)

www. Type 27A Depressed Center Cutting Off Wheels are wheels having diameter, thickness, and hole size dimensions. They are reinforced, organic bonded, offset hub type wheels, usually 16 inches diameter and larger, specially designed for use on cutting-off machines where mounting nut or outer flange interference cannot be tolerated. Limitations: See sub-section 250.21.x through sub-section 250.21.cc. of this section. (7-1-97)

xxx. Unitized Tooling is 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. (7-1-97)

03. General Requirements (7-1-97)

a. 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, shears, and sparks. Example of guarding methods are: Barrier guards, two (2) hand tripping devices, electronic safety devices, etc. (7-1-97)

b. 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. (7-1-97)

04. Guarding: (7-1-97)

a. Point of operation is the area on a machine where work is actually performed upon the material being processed. (7-1-97)

b. The point of operation of machines whose operation exposes an employee to injury shall be guarded. The guarding device shall be in conformity with any appropriate standards thereof, or, in the absence of applicable specific standards, shall be so designed and constructed as to prevent the operator from having any part of his body in the danger zone during the operating cycle. (7-1-97)

c. Special hand tools for placing and removing material shall be such as to permit easy handling of material without the operator placing a hand in the danger zone. Such tools shall not be in lieu of other guarding required by this section, but can only be used to supplement protection provided. (7-1-97)

d. The following are some of the machines which usually require point of operation guarding: guillotine cutters, paper cutters (manual and power), shears, alligator shears, power presses, milling machines, power saws, Jointers, portable power tools, forming tools and calenders. (7-1-97)

e. Revolving drums, barrels, and containers shall be guarded by an enclosure which is interlocked with the drive mechanism, so that the barrel, drum, or container cannot revolve unless the guard enclosure is in place. (7-1-97)

f. When the periphery of the blades of a fan is less than seven (7) feet above the floor or working level, the blades shall be guarded. The guard shall have openings no larger than one-half (1/2) inch. Safeguards shall be so constructed that rods, pipes, or like material being handled by workmen will not enter same, and come in contact with moving machinery. (7-1-97)

g. Cams and other machine parts which move in such a manner as to create shearing or crushing hazards shall, if exposed to contact, be guarded with a standard safeguard. (7-1-97)

h. All counterweights exposed to contact shall be guarded with standard safeguards. (7-1-97)

i. All belts, pulleys, gears, shafts, and moving parts shall be guarded in accordance with the specific requirements of this standard. (7-1-97)

05. Anchoring Fixed Machinery: (7-1-97)

a. Machines designed for a fixed location shall be securely anchored to prevent walking or moving. (7-1-97)

06. Means to Prevent Slipping: (7-1-97)

a. Operators of dangerous machinery, such as shapers, jointers, and circular saws, shall be safeguarded against slipping on smooth, oily or otherwise slippery floor, where he stands while at the point of operation of such dangerous machinery, by covering such portion of the floor with a rubber mat, cork, non-slip composition flooring, or some other effective means of preventing slipping. (7-1-97)

07. Repairs: (7-1-97)

a. The workman making the repairs or adjustments shall tag and/or lock out the main disconnecting device, warning that the machine shall not be started. The said tag and/or lock shall not be removed by any other person than the one (1) who attached it, unless authorized by a department head, i.e., superintendent or foreman, after proper investigation and notification to the person applying the tag and/or lock. These tags and/or locks shall carry the name of the person applying, and the time and date of application. (7-1-97)

b. All power-driven machinery shall be stopped and brought to a complete standstill before any repairs or adjustments are made, or pieces of material or refuse removed, except where motion is necessary to make adjustment. (7-1-97)

08. Machine Construction: (7-1-97)

a. Each machine shall be so constructed as to be free from sensible vibration when the largest size tool is mounted and run idle at full speed. (7-1-97)

b. Arbors and mandrels shall be constructed so as to have firm and secure bearing and be free from play. (7-1-97)

c. The use of wooden band saw wheels other than those of commercial manufacture is prohibited. (7-1-97)

d. Any automatic cutoff saw that strokes continuously without the operator being able to control each stroke shall not be used. (7-1-97)

e. Saw frames or tables shall be constructed with lugs cast on the frame or with an equivalent means to limit the size of the saw blade that can be mounted, so as to avoid over speed caused by mounting a saw larger than intended. (7-1-97)

f. Circular saw fences shall be so constructed that they can be firmly secured to the table or table assembly without changing their alignment with the saw. For saws with tilting tables or tilting arbors the fence shall be so constructed that it will remain in a line parallel with the saw, regardless of the angle of the saw with the table. (7-1-97)

g. Circular saw gages shall be so constructed as to slide in grooves or tracks that are accurately machined, to insure exact alignment with the saw for all positions of the guide. (7-1-97)

h. Hinged saw tables shall be so constructed that the table can be firmly secured in any position and in true alignment of the saw. (7-1-97)

i. Each power-driven woodworking machine shall be provided with a disconnect switch that can be locked in the off position. (7-1-97)

j. The frames and all exposed, non-current-carrying metal parts of portable electric wood working machinery operated at more than fifty (50) volts to ground shall be grounded and other portable motors driving electric tools which are held in the hand while being operated shall be grounded if they operate at more than fifty (50) volts to ground. The ground shall be provided through use of a separate ground wire and polarized plug and receptacle. EXCEPTION: Double insulated hand held power tools. (7-1-97)

k. For all circular saws where conditions are such that there is a possibility of contact with the portion of the saw either beneath or behind the table, that portion of the saw shall be covered with an exhaust hood, or, if no exhaust system is required, with a guard that shall be so arranged as to prevent accidental contact with the saw. (7-1-97)

l. Revolving double arbor saws shall be fully guarded in accordance with all the requirements for circular crosscut saws or with all the requirements for circular ripsaws, according to the kind of saws mounted on the arbors. (7-1-97)

m. No saw, cutter head, or tool collar shall be placed or mounted on a machine arbor unless the tool has been accurately machined to size and shape to fit the arbor. (7-1-97)

n. Combs (feather boards) or suitable jigs shall be provided at the workplace for use when a standard guard cannot be used, as in dadoing, grooving, jointing, molding, and rabbeting. (7-1-97)

09. Machine Controls: (7-1-97)

a. A mechanical or electrical power control shall be provided on each machine to make it possible for the operator to cut off the power from each machine without leaving his position at the point of operation. (7-1-97)

b. On applications where injury to the operator might result if motors were to restart after power failures, provision shall be made to prevent machines from automatically restarting upon restoration of power. (7-1-97)

c. Power controls and operating controls should be located within easy reach of the operator while he is at his regular work location, making it unnecessary for him to reach over the cutter to make adjustments. This does not apply to constant pressure controls used only for setup purposes. (7-1-97)

d. On each machine operated by electric motors, positive means shall be provided for rendering such controls or devices inoperative while repairs or adjustments are being made to the machines they control. (7-1-97)

e. Each operating treadle shall be protected against unexpected or accidental tripping. (7-1-97)

f. Feeder attachments shall have the feed rolls or other moving parts so covered or guarded as to protect the operator from hazardous points. (7-1-97)

10. Hand-Fed Ripsaws and Crosscut Table Saws: (7-1-97)

a. Each circular hand-fed ripsaw and crosscut table saw shall be guarded by a hood which shall completely enclose that portion of the saw above the table and that portion of the saw above the material being cut. The hood and mounting shall be arranged so that the hood will automatically adjust itself to the thickness of and remain in contact with the material being cut but it shall not offer any considerable resistance to insertion of material to saw or to passage of the material being sawed. The hood shall be made of adequate strength to resist blows and shall be so designed as to protect the operator from flying splinters and broken saw teeth. It shall be made of material that is soft enough so that it will be unlikely to cause tooth breakage. The material shall not shatter when broken, should be nonexplosive, and should be no more flammable than wood. The hood shall be so mounted as to insure that its operation will be positive, reliable and in true alignment with the saw; and the mounting shall be adequate in strength to resist any reasonable side thrust or other force tending to throw it out of line. (7-1-97)

b. Each hand-fed circular ripsaw and crosscut table saw shall be furnished with a spreader to prevent material from squeezing the saw or being thrown back on the operator. The spreader shall be made of hard tempered steel, or its equivalent, and shall be thinner than the saw kerf. It shall be of sufficient width to provide adequate stiffness or rigidity to resist any reasonable side thrust or blow tending to bend or throw it out of position. The spreader shall be attached so that it will remain in true alignment with the saw even when either the saw or table is tilted, and should be placed so that there is not more than one-half (1/2) inch space between the spreader and the back of the saw when the largest saw is mounted in the machine. The provision of a spreader in connection with grooving, dadoing, or rabbeting is not required. On the completion of such operations, the spreader shall be immediately replaced. (7-1-97)

c. Each hand-fed circular ripsaw and crosscut table saw shall be provided with non-kickback fingers on dogs so located as to oppose the thrust or tendency of the saw to pick up the material or to throw it back toward the operator. They shall be designed to provide adequate holding power for all the thicknesses of materials being cut. (7-1-97)

11. Swing Cutoff Saws: (7-1-97)

a. The requirements of this section are also applicable to sliding cutoff saws mounted above the table. (7-1-97)

b. Each swing cutoff saw shall be provided with a hood that will completely enclose the upper half of the saw, the arbor end, and the point of operation at all positions of the saw. The hood shall be constructed in such a manner and of such material that it will protect the operator from flying splinters and broken saw teeth. Its hood shall be so designed that it will automatically cover the lower portion of the blade, so that when the saw is returned to the back of the table the hood will rise on top of the fence, and when the saw is moved forward the hood will drop on top of and remain in contact with the table or material being cut. (7-1-97)

c. Each swing cutoff saw shall be provided with an effective device to return the saw automatically to the back of the table when released at any point of its travel. Such a device shall not depend for its proper functioning upon any rope, cord, or swing. If there is a counterweight, the bolts supporting the bar and counterweight shall be provided with cotter pins; and the counter-weight shall be prevented from dropping by either a bolt passing through both the bar and counterweight, or a bolt put through the extreme end of the bar, or, where the counter-weight does not encircle the bar, a safety chain attached to it. (7-1-97)

d. Limit chains or other equally effective devices shall be provided to prevent the saw from swinging beyond the front or back edges of the table, or beyond a forward position where the gullets of the lowest saw teeth will rise above the table top. (7-1-97)

e. Inverted swing cutoff saws shall be provided with a hood that will cover the part of the saw that protrudes above the top of the table or above the material being cut. It shall automatically adjust itself to the thickness of and remain in contact with the material being cut. (7-1-97)

12. Radial Saws: (7-1-97)

a. The upper hood shall completely enclose the upper portion of the blade down to a point that will include the end of the saw arbor. The upper hood shall be constructed in such a manner and of such material that it will protect the operator from flying splinters, broken saw teeth, ect., and will deflect sawdust away from the operator. The sides of the lower exposed portion of the blade shall be guarded to the full diameter of the blade by a device that will automatically adjust itself to the thickness of the stock and remain in contact with stock being cut to give maximum protection possible for the operation being performed. (7-1-97)

b. Each radial saw used for ripping shall be provided with non-kickback fingers or dogs located on both sides of the saw so as to oppose the thrust or tendency of the saw to pick up the material or to throw it back toward the operator. They shall be designed to provide adequate holding power for all the thickness of material being cut. (7-1-97)

c. An adjustable stop shall be provided to prevent the forward travel of the blade beyond the position necessary to complete the cut in repetitive operations. (7-1-97)

d. Installation shall be in such a manner that the front end of the unit will be slightly higher than the rear, so as to cause the cutting head to return gently to the starting position when released by the operator. (7-1-97)

e. Ripping and ploughing shall be against the direction in which the saw turns. The direction of the saw rotation shall be conspicuously marked on the hood. In addition, a permanent label not less than one and one-half (1 1/2) inches by three-fourths (3/4) inch shall be affixed to the rear of the guard at approximately the level of the arbor, reading as follows: "DANGER: DO NOT RIP OR PLOUGH FROM THIS END". Such a label shall be colored standard danger red. (7-1-97)

13. Band Saws: (7-1-97)

a. All portions of the saw blade shall be enclosed or guarded except for the working portion of the blade between the bottom of the guide rolls and the table. Band saw wheels shall be fully encased. The outside periphery of the enclosure shall be solid. The front and back of the band wheels shall be either enclosed by solid material or by wire mesh or perforated metal. Such mesh or perforated metal shall be not less than zero-point-zero-thirty-seven (0.037) inch (U.S. Gage No. 20), and the openings shall be not greater than three-eights (3/8) inch. Solid material used for this purpose shall be of an equivalent strength and firmness. The guard for the portion of the blade between the sliding guide and the upper-saw-wheel guard shall protect the saw blade at the front and outer side. This portion of the guard shall be self-adjusting to raise and lower with the guide. The upper-wheel guard shall be made to conform to the travel of the saw on the wheel, and the top member of the guard should have at least a two (2) inch clearance outside the saw and be lined with smooth material, preferably metal. Effective brakes should be provided to stop the wheel in case of blade breakage. (7-1-97)

b. Each band saw machine shall be provided with a tension control device to indicate a proper tension for the standard saws used on the machine, in order to assist in the elimination of saw breakage due to improper tension. (7-1-97)

14. Jointers: (7-1-97)

a. Each hand-fed planer and jointer with horizontal head shall be equipped with a cylindrical cutting head, the knife projection of which shall not exceed one-eighth (1/8) inch beyond the cylindrical body of the head. (7-1-97)

b. The opening in the table shall be kept as small as possible. The clearance between the edge of the rear table and the cutter head shall be not more than one-eighth (1/8) inch. The table throat opening shall be not more than two and one-half (2 1/2) inches when tables are set or aligned with each other for zero (0) cut. (7-1-97)

c. Each hand-fed jointer with a horizontal cutting head shall have an automatic guard which will cover all the section of the head on the working side of the fence or gage. The guard shall effectively keep the operator's hand from coming in contact with the revolving knives. The guard shall automatically adjust itself to cover the unused portion of the head and shall remain in contact with the material at all times. (7-1-97)

d. Each hand-fed jointer with horizontal cutting head shall have a guard which will cover the section of the head back of the gage or fence. (7-1-97)

e. Each wood jointer with vertical head shall have either an exhaust hood or other guard so arranged as to enclose completely the revolving head, except for a slot of such width as may be necessary and convenient for the application of the material to be jointed. (7-1-97)

15. Boring and Mortising Machines: (7-1-97)

a. Safety-bit chucks with no projecting set screws shall be used. (7-1-97)

b. Boring bits should be provided with a guard that will enclose all portions of the bit and chuck above the material being worked. (7-1-97)

c. The top of the cutting chain and driving mechanism shall be enclosed. (7-1-97)

d. If there is a counterweight, one of the following or equivalent means shall be used to prevent its dropping: (7-1-97)

i. It shall be bolted to the bar by means of a bolt passing through both bar and counterweight; (7-1-97)

ii. A bolt shall be put through the extreme end of the bar; (7-1-97)

iii. Where the counterweight does not encircle the bar, a safety chain shall be attached to it. (7-1-97)

iv. Other types of counterweights shall be suspended by chain or wire rope and shall travel in a pipe or other suitable enclosure wherever they might fall and cause injury. (7-1-97)

e. Universal joints on spindles of boring machines shall be completely enclosed in such a way as to prevent accidental contact by the operator. (7-1-97)

f. Each operating treadle shall be covered by an inverted U-shaped metal guard, fastened to the floor, and of adequate size to prevent accidental tripping. (7-1-97)

16. Wood Shapers and Similar Equipment: (7-1-97)

a. The cutting heads of each wood shaper, hand-fed panel raiser, or other similar machine not automatically fed, shall be enclosed with a cage or adjustable guard so designed as to keep the operator's hand away from the cutting edge. The diameter of circular shaper guards shall be not less than the greatest diameter of the cutter. In no case shall a warning device of leather or other material attached to the spindle be acceptable. (7-1-97)

b. Cylindrical heads should be used whenever the nature of the work will permit. Single cutter knives in shaper heads shall not be used unless properly balanced. (7-1-97)

c. All double-spindle shapers shall be provided with a spindle starting and stopping device for each spindle. (7-1-97)

17. Planing and Molding Machines: (7-1-97)

a. Each planing and molding machines shall have all cutting heads, and saws if used, covered by a metal guard. If such guard is constructed of sheet metal, the material used shall be not less than one-sixteenth (1/16) inch in thickness, and if cast iron is used, it shall be not less than three-sixteenths (3/16) inch in thickness. (7-1-97)

b. Where an exhaust system is used, the guards shall form part or all of the exhaust hood and shall be constructed of metal of a thickness not less than that specified in sub-section 250.15.a. of this section. (7-1-97)

c. Feed rolls shall be guarded by a hood or suitable guard to prevent the hands of the operator from coming in contact with the in-running rolls at any point. The guard shall be fastened to the frame carrying the rolls so as to remain in adjustment for any thickness of stock. (7-1-97)

d. Surfacers or planers used in thicknessing multiple pieces of material simultaneously shall be provided with sectional in-feed rolls having sufficient yield in the construction of the sections to provide feeding contact pressure on the stock, over the permissible range of variation in stock thickness specified or for such yielding sectional rolls, suitable section kickback finger devices shall be provided at the in-feed end. (7-1-97)

18. Profile and Swing-Head Lathes and Wood Heel Turning Machine: (7-1-97)

a. Cutting heads on wood-turning lathes, whether rotating or not, shall be covered as completely as possible by hoods or shields, which shall be hinged to the machines so that they can be thrown back for making adjustments. (7-1-97)

b. Lathes used for turning long pieces of wood stock held only between the two centers shall be equipped with long curved guards extending over the tops of the lathes in order to prevent the work pieces from being thrown out of the machines if they should become loose. (7-1-97)

c. Where an exhaust system is used, the guard shall form part or all of the exhaust hood and shall be constructed of metal of a thickness not less than that specified in a. of this subsection. (7-1-97)

19. Sanding Machines: (7-1-97)

a. Feed rolls of self-feed sanding machines shall be protected with a semi-cylindrical guard to prevent the hands of the operator from coming in contact with the in-running rolls at any point. The guard shall be constructed of heavy material, preferably metal, and firmly secured to the frame carrying rolls so as the remain in adjustment for any thickness of stock. The bottom of the guard should come down to within three-eighths (3/8) inch of a plane formed by the bottom or contact face of the feed roll where it touches the stock. (7-1-97)

b. Each drum sanding machine shall have an exhaust hood, or other guard if no exhaust system is required, so arranged as to enclose the revolving drum, except for that portion of the drum above the table, if a table is used which may be necessary and convenient for the application of the material to be finished. (7-1-97)

c. Each disk sanding machine shall have the exhaust hood, or other guard if no exhaust system is required, so arranged as to enclose the revolving disk, except for that portion of the disk above the table, if a table is used, which may be necessary for the application of the material to be finished. (7-1-97)

d. Belt sanding machines shall be provided with guards at each nip point where the sanding belt runs on to a pulley. These guards shall effectively prevent the hands or fingers of the operator from coming in contact with the nip points. The unused run of the sanding belt shall be guarded against accidental contact. (7-1-97)

20. Inspection and Maintenance of Woodworking Machinery: (7-1-97)

a. Dull, badly set, improperly filed, or improperly tensioned saws shall be immediately removed from service before they begin to cause the material to stock, jam, or kickback when it is fed to the saw at normal speed. Saws to which gum has adhered on the sides shall be immediately cleaned. (7-1-97)

b. All knives and cutting heads of woodworking machines shall be kept sharp, properly adjusted, and firmly secured. Where two or more knives are used in one head, they shall be properly balanced. (7-1-97)

c. Bearings shall be kept free from lost motion and shall be well lubricated. (7-1-97)

d. Arbors of all circular saws shall be free from play. (7-1-97)

e. Sharpening or tensioning of saw blades or cutters shall be done only by persons of demonstrated skill in this kind of work. (7-1-97)

f. Emphasis is placed upon the importance of maintaining cleanliness around woodworking machinery, particularly as regards the effective functioning of guards and the prevention of fire hazards in switch enclosures, bearings, and motors. (7-1-97)

g. All cracked saws shall be removed from service. (7-1-97)

h. The practice of inserting wedges between the saw disk and the collar to form what is commonly known as a "wobble saw" shall not be permitted. (7-1-97)

i. Push sticks or push blocks shall be provided at the work place in several sizes and types suitable for the work to be done. (7-1-97)

j. Twists or kinks in band-saws shall be promptly removed with a hammer. (7-1-97)

k. To avoid vibration, brazed joints in band-saws shall be the same thickness as the saw blades. (7-1-97)

l. The knife blade of jointers shall be so installed and adjusted that it does not protrude more than one-eighth (1/8) inch beyond the cylindrical body of the head. Push sticks or push blocks shall be provided at the work place in several sizes and types suitable for the work to be done. (7-1-97)

21. Abrasive Wheel Machinery. (7-1-97)

a. Abrasive wheels shall be used only on machines provided with safety guards. EXCEPTIONS: Wheels used for internal work while within the work being ground; mounted wheels used in portable operations 2-inches and smaller in diameter; and types 16, 17, 18, 18R, and 19 cones, plugs, and threaded hole pit balls where the work offers protection. (7-1-97)

b. The safety guard shall cover the spindle end, nut, and flange projections. The safety guard shall be mounted so as to maintain proper alignment with the wheel, and the strength of the fastenings shall exceed the strength of the guard. EXCEPTIONS: Safety guards on all operations where the work provides a suitable measure of protection to the operator, may be so constructed that the spindle end, nut, and outer flange are exposed; and where the nature of the work is such as to entirely cover the side of the wheel, the side covers of the guard may be omitted; and the spindle end, nut, and outer flange may be exposed on machines designed like portable saws. (7-1-97)

c. Grinding machines shall be equipped with flanges in accordance with sub-section 250.21.x. through sub-section 250.21.cc. of this section. (7-1-97)

d. On off-hand grinding machines, work rests shall be used to support the work. They shall be of rigid construction and designed to be adjustable to compensate for wheel wear. Work rests shall be kept adjusted closely to the wheel with a maximum opening of one-eighth (1/8) inch to prevent the work from being jammed between the wheel and the rest, which may cause wheel breakage. The work rest shall be securely clamped after each adjustment. The adjustment shall not be made with the wheel in motion. (7-1-97)

e. Natural sandstone wheels and metal, wooden, cloth, or paper discs, having a layer of abrasive on the surface are not covered by sub-section 250.21 of this section. (7-1-97)

f. Cup wheels (Types 6 and 11) shall be protected by: safety guards as specified in sub-section 250.21.f. through sub-section 250.23.w. this section; band type guards as specified in sub-section 250.21.v. of this section; and special revolving cup guards which mount behind the wheel and turn with it. They shall be made of steel or other material with adequate strength and shall enclose the wheel sides upward form the back for one-third (1/3) of the wheel thickness. The mounting features shall conform with all requirements of this section. It is necessary to maintain clearance between the wheel side and the guard. This clearance shall not exceed one-sixteenth (1/16) inch. (7-1-97)

g. The maximum exposure angles specified in sub-section 250.21.g. through sub-section 250.21.l. of this section shall not be exceeded. Visors or other accessory equipment shall not be included as a part of the guard when measuring the guard opening, unless such equipment has strength equal to that of the guard. (7-1-97)

h. The angular exposure of the grinding wheel periphery and sides for safety guards used on machines known as bench and floor stands should not exceed nighty (90) degrees or one-fourth (1/4) of the periphery. This exposure shall begin at a point not more than sixty-five (65) degrees above the horizontal plane of the wheel spindle. (See Figure 250.21-A). Wherever the nature of the work requires contact with the wheel below the horizontal plane of the spindle, the exposure shall not exceed one-hundred-twenty-five (125) degrees. (See Figure 250.21-B) (7-1-97)

FIGURE 250.21-A

FIGURE 250.21-B

i. The maximum angular exposure of the grinding wheel periphery and sides for safety guards used on cylindrical grinding machines shall not exceed one-hundred-eighty (180) degrees. This exposure shall begin at a point not more than Sixty-five (65) degrees above the horizontal plane of the wheel spindle. (See Figure 250.21-C). (7-1-97)

FIGURE 250.21-C

j. The maximum angular exposure of the grinding wheels periphery and sides for safety guards used on cutting-off machines and on surface grinding machines which employ the wheel periphery shall not exceed one-hundred-fifty (150) degrees. This exposure shall begin at a point not less than fifteen (15) degrees below the horizontal plane of the wheel spindle. (See Figures 250.21-D). (7-1-97)

FIGURE 250.21-D

k. The maximum angular exposure of the grinding wheel periphery and sides for safety guards used on machines shall not exceed one-hundred-eighty (180) degrees, and the top half of the wheel shall be enclosed at all times. (See Figures 250.21-E). (7-1-97)

FIGURE 250.21-E

l. The maximum angular exposure of the grinding wheel periphery and sides known as automatic snagging machines shall not exceed one-hundred-eighty (180) degrees and the top half of the wheel shall be enclosed at all times. (See Figure 250.21-E) (7-1-97)

m. Where the work is applied to the wheel above the horizontal center line, the exposure of the grinding wheel periphery shall be as small as possible and shall not exceed sixty (60) degrees. (See Figure 250.21-F). (7-1-97)

FIGURE 250.21-F

n. Safety guards of the types described in sub-section 250.21.h. and sub-section 250.23.i. of this section, where the operator stands in front of the opening shall be constructed so that the peripheral protecting member can be adjusted to the constantly decreasing diameter of the wheel. The maximum angular exposure above the horizontal plane of the wheel spindle as specified in sub-section 250.21.h. and sub-section 250.23.i. of this section, shall never be exceeded, and the distance between the wheel periphery and the adjustable tongue or the end of the peripheral member at the top shall never exceed one-fourth (1/4) inch. See Figure 250.21-G and Table 250.21-A for minimum basic thickness of peripheral and side members for various types of safety guards and classes of service. (7-1-97)

FIGURE 250.21-G