Belt Conveyors 1

National Safety Council

Data Sheet 569 Rev. May 2005

Abelt conveyor is an arrangement ofmechanical components that supports

and propels a conveyor belt, which in turncarries bulk material. The five principalcomponents of a typical belt conveyor are:(a) the belt, which forms the moving andsupporting surface on which the conveyedmaterial rides; (b) the idlers, which formthe supports for carrying the belt; (c) thepulleys, which support and move the beltand control its tension; (d) the drive, whichimparts power to one or more pulleys tomove the belt and its load; (e) the struc-ture, which supports and maintains thealignment of the idlers and pulleys and sup-ports the driving machinery (see Figure 1);(f) the enclosures through which the bulkmaterial is deposited onto the belt or dis-charged from the belt.2. Belt conveyors have been in use formore than 150 years. Because of the econ-omy and efficiency with which belts movematerials, their use has increased to thepoint where they have become one of themost common means of conveyance in theplant. Like all moving machinery, belt con-veyors present hazards to workers andmust be safeguarded.3. This data sheet discusses equipment forconveyor safety and environmental control– such as guards, safe construction fea-tures, fire prevention measures, conveyorcontrol and dust control devices. DataSheet 570, Belt Conveyors for BulkMaterials—Part 2: Operations, discussessafe work procedures.4. Safety aspects of conveying systemsshould be discussed with suppliers of newequipment before specifications are writ-ten and quotations obtained. The conveyorpurchaser should decide the safety fea-

tures, training features and maintenancefeatures to be furnished in order to complywith state and federal rules and regulationspertaining to the safety, health, and welfareof the worker before a contract with thesupplier is signed. It is difficult and expen-sive for the purchaser to provide over-looked safety features after the conveyingequipment is delivered. In the end, howev-

Belt conveyors for bulk materials Part 1: Equipment

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Figure 1. The belt conveyor delivers bulk material to

storage piles. The belt, idlers, drive and walkway are

supported by the conveyor frame.



er, conveyor users must supply safeguardsthat manufacturers cannot supply, and theyalso must supply safety devices for exist-ing installations to comply with state andfederal regulations.5. The following injuries and hazards maybe reduced by proper guards and environ-mental controls on bulk handling conveyors:a. Injuries from nip points. Usually employ-

ees are pulled in when their hands, cloth-ing, or tools are caught in the nip point.

b. Injuries from pieces of material fallingfrom moving conveyors

c. Injuries and deaths to workers crushedagainst stationary objects by movingconveyors

d. Injuries to workers who fall from movingconveyors while riding on them or fromconveyors that are started while they arestanding or working on them

e. Injuries to workers who reach in aroundguards at head and tail pulleys that arerunning

f. Injuries to workers who service movingconveyor belts

g. Injuries to workers who fall while tryingto cross over conveyors where there isno crosswalk

h. Fires from friction, overheating, or staticor other electrical sources

i. Explosions of dust raised by combustiblematerials at transfer points, where beltsare loaded or discharged.

j. Hazards to health and vision from irritat-ing or toxic dusts

k. Electrical shock from ungrounded orimproperly installed controls or conduc-tors

l. Muscle strain injuries resulting fromcleaning spills

6. There are many nip points (sometimescalled pinch points) on conveyors: betweenthe belt and its drive, take-up, bend, and tailpulleys; between wheels and rails on shut-tle conveyors; between skirt plates and

troughing and return idler rolls; in or aroundpower-transmission parts. The large, heavi-ly loaded belts used in mining and con-struction, and in the cement, quarry andmineral aggregate industries pose a moresevere hazard than small, light-duty beltsused in some other industries. Still, evensmall belts cannot be disregarded with re-spect to safety.7. Many workers have been caught andseverely injured while working in areas ofthe drive, tail and take-up pulleys. Theseaccidents have occurred when:a. A worker’s loose clothing is pulled into a

moving pulley and beltb. A worker attempts to apply a belt dress-

ing to a pulley to prevent a belt from slip-ping. Some employees have beencaught when trying to throw “fines” orsand between a slipping belt and pulley.

c. A worker attempts to clean stickingmaterial from moving belts and pulleys

d. A worker, “cleaning up” around a tailpulley, shovels against the direction ofthe moving belt

e. A worker attempts to service pulleyswhile they are operating

Guards against nip injuries

8. Painting guards according to the colorstandard (ANSI Z53.1) is an important safe-ty measure because it helps workers seeand avoid hazardous moving parts. Paintedtravel ways should be clearly defined withsigns and proper illumination.9. Transmission equipment and other power-driven parts should be guarded in accor-dance with the Safety Standard forMechanical Power-Transmission Apparatus,ANSI B15.1, and with any state (or provincial)or federal regulation governing the safety,health and welfare of employees. The ANSIstandard stipulates how pulleys, chains,sprockets, belts, couplings and other parts ofconveyor drives should be enclosed.

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10. Suitable sweeps should be providedfor shuttle conveyors, movable trippers,traveling plows, and hoppers and stackersto push objects ahead of the moving nippoints between the wheels and the rails, inorder to guard against nips. Again, it isimperative to comply with all state (orprovincial) and federal regulations.11. Nip points at the head, tail and take-uppulleys should be completely guarded. Thesides of each belt should be enclosed farenough back along the run (at least 36 inch-es), so no one can reach in, over or aroundto contact the nip between belt and pulley(see Figure 2). Belt pulleys require skirtguards in addition to reach guards.12. An idler pulley becomes a hazard whenskirt plates and chute skirts are so posi-tioned as to force the belt against the idlerand create a nip point. If there is no roomfor the belt to lift, the idlers must be guard-ed. Another hazard occurs when a stonegets caught between the end idler roll andthe mounting bracket, and an employeeattempts to remove the stone with his

hand while the conveyor is operating.13. Mechanical belt cleaners, such as fixedor tension scrapers, revolving brushes, orrubber disks, sometimes eliminate manualcleaning (see Figure 4). They also eliminatea major reason for working around movingpulleys.14. Guards should be sturdily constructedand designed to withstand conveyor vibra-tion. They also should be easy to removeand replace for maintenance (see Figure 5).Take-ups and drive adjustments should beeasily accessible. A means for easy accessfor cleaning of spillage also should be con-sidered in any guard design, including entryfor small mobile equipment, which wouldeliminate most manual labor clean-up.15. In order to lubricate a conveyor in con-tinuous operation, extension grease linesshould be installed to prevent a workerfrom being caught by rollers and bearingswhen he is working around them (seeFigure 6). All grease fittings inside a guardenclosure (except those that move withthe part they serve) should be fitted with

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Figure 2. Enclosing the sides of the belt will preventcontact with nip points. Grease fillings are placed soguard does not have to be removed while servicing.

Figure 3. Skirt plates prevent material from falling offconveyors, but also may create nip points at idlers ifthey prevent belts from lifting freely.



extension pipes to make them accessiblefrom outside the guard (see Figure 5).Sometimes pressure lubrication or auto-matic gravity oilers (where a central lubri-cant reservoir is used to feed one or morebranch lines, which lubricate moving partsof the conveyor) may not only eliminate asource of injury to oilers, but may decreasethe cost of lubrication.

Belt take-ups and backstops

16. All properly designed belt conveyorsrequire the use of some form of take-updevice for the following four reasons:a. To keep the proper amount of slack side

tension at the drive pulley to prevent beltslippage

b. To assure proper belt tension at loadingand other points along the conveyor toprevent loss of troughing contour of thebelt between idlers, thus avoidingspillage of material from the belt

c. To compensate for stretch or shrinkageof the belt

d. To allow belt storage for making replace-ment splices. Take-ups may be designedfor periodic manual adjustment or forautomatic adjustment by the use ofcounterweights or by hydraulic or pneu-matic means.

17. The manually adjusted take-up, usuallya screw type, has the advantages of com-pactness and low cost. The disadvantagesare:a. The take-up must be made manually,

while the conveyor is operating, becauseeach screw must be adjusted separatelyto make sure the belt tracks properlyalong the length of the conveyor.

b. Because the take-up is periodic, theresulting belt tensions are almost alwaystoo high or too low. It is imperative thetail pulley and shaft be properly guardedto ensure the worker’s safety while man-ually adjusting the take-up.

18. Automatic take-ups are the most desir-able type for use on any belt conveyor.They can be installed horizontally, vertically,

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Figure 4. A simple fixed scraper will prevent build-upof materials on the belt and will do away with unsafecleaning while the belt is moving.

Figure 5. Complete skirt guards prevent spillage andkeep clothing from catching in pulleys along much-traveled walkways. Extension pipes for lubricatingidlers extend through easily removable guards.

or on an incline. They can be either gravityoperated or power operated by hydraulic,electric or pneumatic means. The mostcommon type of automatic take-up is thegravity take-up.19. The gravity take-up pulley is counter-weighted, and hangs down in a loop of thebelt under the conveyor to maintain belttension (see Figure 7). Where accessibleby personnel, these counterweighted pul-leys and associated turn pulleys must betotally enclosed to protect workers frombeing caught in their nip and pinch points.Other precautions include a limit switch atthe bottom of the weight travel to indicateneed for a major adjustment, as well asautomatic safety stops to hold the pulleysif their suspension supports fail.20. A loaded inclined belt conveyor of suf-ficient slope tends to move backwardswhen forward motion is stopped by a ces-sation or interruption of power or amechanical failure in the driving machinery.Should the loaded belt move backwards,the material will pile up at the tail end of the

conveyor. This could seriously damage thebelt, and result in the need to clean up anddispose of the spilled material. To preventthis reversal of motion, a backstop is used.21. A backstop is a mechanical deviceallowing the conveyor to operate only inthe desired direction. It allows free rotationof the drive pulley in the forward direction,but automatically prevents rotation of thedrive pulley in the opposite direction. Thereare three general backstop designs: ratchet



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Figure 6. Extension lines on lubrication fittings willkeep workers at a safe distance from pinch pointswhile they grease the idlers.

Figure 7. Guards, such as the one shown here, willprevent workers from walking under take-ups.

and pawl, differential band brake and over-running clutch. Backstop devices must bechecked periodically with a normal load onthe belt to see if they operate properly.

Guards against falling material

22. Pieces of material rolling back downsteeply inclined, lightly-loaded belts can bea hazard. The maximum safe angle for theconveyor should be carefully determinedby experienced people. Careful considera-tion also should be given to loading andtransfer points in order to prevent rollbackby properly and evenly distributing materialon the belt. Skirt plates should be providedwhere there is a tendency of material to rollback down the belt (see Figure 3).23. Any conveyor that passes over anaisle, passageway or workplace must beenclosed on the bottom and sides to pro-tect people below from falling material.24. Side skirts along the length of the con-veyor belt hold material on the belt, pre-venting spillage on the walkways andfalling material from striking employees.25. Cleaning spillage around conveyorscontributes to a great number of injuries.Ample clearance under conveyors for safemanual cleanup of occasional spillage helpsprevent accidents. Ideally, clearance shouldbe such that a small machine could beused in cleaning up spillage. Great careshould be taken to ensure nip points areproperly guarded. Hazards particular toother clean-up methods also should beaddressed, such as drainage and a protect-ed sump for flushing material with waterand access for vacuum equipment.Transfer points and feed chutes must bedesigned so no “plugging” occurs, thusminimizing spillage. Overhead belts mustbe guarded if the whipping action from abroken belt would be hazardous to personsbelow.26. At transfer points, wear liners inside the

skirtboards and seals below the skirtboardswill help to prevent material from beingejected from the conveyor. Application ofwater on the conveyor should be minimizedto help prevent the slide of material on asloped conveyor.

Guards against crushing injuries

27. Enough clearance should be providedbetween conveyors and stationary objectsso employees cannot be crushed betweenthem. Where it is not possible to providethis clearance between or under stationaryobjects, a gate guard ahead of this lowclearance will shut off the power when thegate is contacted.

Conveyors running in pits or tunnelsshould have ample side clearance to permitsafe repair work and oiling. Illuminationshould be adequate where workers oper-ate close to conveyors, as in pits and tun-nels or on walkways.28. Belt conveyors passing over designat-ed walkways or work areas where there isless than 7 feet clearance should have thebelt underpass protected with expandedmetal or screen of 3⁄4-inch clear opening orless. Where there is more than 7 feet clear-ance at designated walkways, passage-ways, or work areas, only the idlers need beguarded, using the expanded metal orscreen of 3⁄4-inch clear opening or less. If,because of build-up of dust falling from abelt, a 3⁄4-inch clear opening is likely tobecome clogged, a clear opening in the ex-panded metal or screen guard for beltunderpasses may be increased to a clearopening not to exceed 2 inches. A solidcanopy guard may be used where there isdanger of material being thrown by returnidlers. Other belt underpasses, which arenot recognized walkways and under 7 feetclearance, should be guarded with a stan-dard hand railing at ground or floor level.Conveyors should be crossed only at desig-



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nated points where elevated, well-litcrossovers equipped with standard railingsare installed to allow workers to cross with-out contacting the conveyor.

Guards around conveyor openings

29. Requirements for guarding floor andwall openings are described in ANSI A12.1,Safety Requirements for Floor and WallOpenings, Railings, and Toeboards. Atpoints where conveyors pass from one floorto another and are not entirely enclosed, theopenings must be protected by standardrailings with toeboards so a person cannotaccidentally walk or fall into the openings.Unprotected pit openings over conveyorsalso must be protected with standard rail-ings and toeboards. If standard railings arenot feasible, a hinged floor plate should beprovided. This will cover the opening andprotect against the spread of fire.30. The top openings of hoppers, when not42 inches or more above adjacent floors orwalkways, must be protected by the samestandard railings or cover plates as for pits.In such instances it may be feasible, whenbelt unloading devices discharge into binsdirectly under them through holes in walk-ways, to cover the openings with gratingjust large enough to pass the material com-ing from the conveyor.

Walkways and tunnels

31. For repairing or oiling overhead con-veyors, suitable work platforms and lad-ders must be provided. Place platforms onwalkways on both sides of the conveyor,unless the work can be performed safelyfrom one side. Open-sided platforms andwalkways 4 feet or more above the adja-cent floor or ground level must be guardedby standard railing 42 inches high with anintermediate rail approximately halfwaybetween the top rail and floor, and a toe-board provided on each platform or walk-

way. These walkways, platforms, stairs,ramps and ladders must be kept in goodrepair and free of spillage or material thatcould become a tripping or falling hazard.They must be lighted whenever naturallighting is insufficient.32. Runways, elevated walkways and plat-forms should meet the requirements ofANSI standards. Inclined and slippery walk-ways must be provided with standard rail-ings and be non-skid or provided withcleats.33. Reclaiming tunnels under surge orstockpiles containing rubber belt conveyingequipment should be of fire-resistantconstruction. Fire extinguishing equip-ment, sufficient to extinguish a fire the fulllength of the belt, should be availableinside the tunnel. Where serious fire haz-ards exist, provisions should be made forthe ventilation of long tunnels to exhaustheat and toxic or flammable gases. A doorthat can be closed should be provided toeliminate draft, in case of fire. Tunnelsshould have at least two ways of escapeavailable for workers trapped inside. Propertunnel design should include:a. Provisions for drainage of waterb. Sufficient lightingc. Sufficient space on each side of the con-

veyor for safe maintenance and removalof spilled material

Loading and unloading

34. Loading hoppers using vibratory panfeeders and similar methods minimizewear on belts, because they feed materialto the belt evenly, over a distance of sever-al feet. Because the feed can be controlled,these devices also prevent the hazard ofexcessive spillage at the loading point andpermit maximum loading of the belt.35. The top edges of loading hoppers andfeeder skirt plates should be rounded orotherwise made blunt so they will not be a

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source of injury to workers.36. Movable receiving hoppers, after beingmoved into position, should be rigidly fas-tened in place to prevent any part or partsfrom catching a moving belt. Where thesehoppers are mounted on wheels andmoved over rails to loading points, sweepguards should be provided to push objectsout of the nip area between wheels andrails. (See Industrial Data Sheet 703, Openand Closed Storage and Reclamation ofStone, Sand, Gravel or Slag.)37. Consult with a reputable engineer, con-veyor manufacturer or conveyor distributorduring the design stage to ensure that thechutes at loading points are designed tominimize safety and health hazards.38. Where a tripper or other movingdeflector device for unloading requires anoperator to travel on it, provide suitableplatform protection with standard railingsand toeboard to keep the operator fromfalling off or coming in contact with themoving parts of the tripper or deflector de-vice. A standard railing should be providedalong the walkway side of the tripper withpreferably a minimum of 15 inches clear-ance between the railing and the tripper.39. If the operator of a self-propelled trip-per is careless while the mechanism is ingear, the tripper may run to the end of therunway or belt and cause an accident. Tominimize this hazard, use a device to throwthe propelling mechanism into neutral, or alimit switch to shut it off at each end of therunway. Another precaution, especiallyuseful where the operator rides the tripper,is a “deadman control” that will not func-tion without the operator’s attention. Asafer substitute for the self-propelled trip-per is an isolated drive, by continuouscable, installed beneath the belt that auto-matically cuts the power and stalls the trip-per, thus preventing its run to the end ofthe belt.

40. It is important when using portableconveyors to have substantial supports andto place the conveyors on level ground toavoid tipping during loading procedures.

Fire prevention

41. Where large amounts of combustiblematerial, such as coal or grain are handled,fires are the outstanding hazard. Belt firescan cause loss of belts, as well as drivemotors, speed reducers, and other equip-ment, resulting in costly production shut-downs. Many conveyors are rated by themanufacturer for the safe operating temper-ature. Rubber belts in particular, unlessaccepted and designated as fire-resistant bythe Mine Safety and Health Administration,can develop a fire at the drive pulley almostwithin seconds, if the belt stalls. A belt mayslip because of overloading or wetting.Other sources of friction that may causefires are:a. Bearing failures, “frozen” rollers and

rollers running hot because of defects orinadequate lubrication

b. Incorrect belt tensionc. Spillage around idlers and tail pulleys

that cause overloading of a beltd. Incorrect threading of the belt, which

may allow the edge to rub against a sta-tionary object

40. To eliminate the fire hazard of a beltstalled while the drive pulley continues toturn, install a safety switch to stop the beltautomatically in the event of excessive slip-page. One type is a centrifugal switch (aroller switch) operated by an idler roll onthe return side of the belt. When the belt isoperating at full speed, centrifugal forcewill keep this switch closed. If the beltloses as little as 5 percent of its ratedspeed, the switch will open and shut downthe belt. Automatic interlocks, if used, willshut down the rest of the belts within thesystem.

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41. To reduce the tension of the belt andto assure sufficient friction between thebelt and the drive pulley, a snub pulley maybe installed to increase the pressure of thebelt against the drive pulley.42. Fires on belt conveyors also may becaused by:a. Electrical failures from substandard elec-

trical installation, worn installation,improper cable splices, lack of ground-ing, undersized electrical components or“plugging” of short circuiting overloadprotectors

b. Static electricityc. Sparks from tramp iron in the material

conveyedd. Careless heating of frozen materials

with an open flame when starting a belt43. Conveyor electrical equipment, includ-ing motors, controls and wiring and itsinstallation must conform to the NationalElectrical Code, NFPA 70. The equipmentshould meet requirements for the Class,Division and Group of hazards caused bythe material the conveyor will handle. Forinstance, electrical equipment for grain-handling conveyors must meet Class II,Group G requirements of the NationalElectrical Code.44. If heating devices for personnel areused around conveying equipment, theyshould be suitable for the hazardous condi-tions in which they will operate.Specifically, unenclosed salamanders, oilburners or heaters with unprotected elec-tric elements should not be used near con-veying equipment. Electrical heaters usednear grain handling conveyors must have aClass II, Group G label. Adequate heatingto prevent freezing of material on astopped belt also is desirable.45. Fuses and overload devices should pro-tect electrical equipment from overloads.“Plugging” or short circuiting these over-load protectors can create a serious fire haz-

ard, and may occur if a worker doesn’t havea fuse available. Workers should be cau-tioned against this practice, and the devicesshould be checked periodically to make cer-tain they are not plugged.46. Static electricity collectors, groundedto the conveyor frame, may help reducefire and explosion hazards on belts thathandle dusty materials or that run throughareas where an explosion hazard exists.Static build-up also is reduced by maintain-ing relative humidity at 60 to 70 percent,and by grounding metal bins to the convey-or frame. Electrical ground connections, atloading and discharge points, can bechecked with static voltmeters or a simpleelectroscope. Continuity of groundingshould be checked once per year or eachtime a change is made.47. Magnetic separators at process entrypoints will remove tramp metal, which mayotherwise spark explosions during thereceipt of bulk grain, meal or other com-bustible materials. Safety Requirementsfor the Textile Industry, ANSI L1.1, rec-ommends magnetic separators to preventfires in starch handling systems. Otherindustries also use them to prevent beltdamage from tramp iron.48. Dust control devices should beinstalled where ambient dust creates a firehazard or a toxic or nuisance pollutant,which directly affects vision or health.Suction hoods (see Figure 8) at the beltloading and discharge points, and at allother points where dust clouds may form,are often advisable. Also, bins and hoppersmay be ventilated (see Figure 8).49. Fan or cone-shaped sprays at dis-charge points are effective in beating downand wetting dust from some minerals.However, avoid wetting the belt. High pres-sure, low volume (fog) suppressions sys-tems optimize the application of water fordust control. Surfactants added to the

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suppression system reduce the amount ofwater needed and improve the wettingcharacteristics of the system. In any case,minimize the free fall of material beingtransferred in order to reduce the dust cre-ated (see Figure 9). Radial stackers that canbe raised or lowered according to theheight of the stock pile also will reducedust. Further information on dust control isgiven in the NFPA codes.

Conveyor control systems

50. Each belt conveyor control point, dis-connect switch, motor starter and push-button should have a nameplate, orotherwise be plainly marked to identify theconveyor being controlled.Note: All unused circuits should be de-energized or otherwise disconnected andconspicuously tagged or labeled.51. Controls and power supplies for each

belt, while the belt is being repaired, must belocked out. Also, a positive means of discon-necting the electrical drives for conveyorsshould be provided on the circuit breaker orswitch controlling the individual drive.Lockout on push buttons and lockouts onpull-cable stops are not positive lockout de-vices. Therefore, the lock must be on themain control switch. Multiple lockout devicesare required where two or more employeesare working on the same equipment.52. To prevent accidents to personnel whomay be surprised by the sudden start of aconveyor, starting controls should be locat-ed where the operator is able to see theentire belt. If a conveyor passes through afloor or wall or into some area that is notvisible from the control point, then addedstarting and stopping push buttons shouldbe installed in each area away from theoperator’s line of sight. These push buttons

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Figure 8. Left: Suction hoods at belt loading and discharge points control nuisance dust. Right: Bin and hop-per ventilation will stop dust problems. Note: Air velocities indicated are minimum standards.

(Drawings courtesy Industrial Ventilation, published by ACGIH).



should be wired in series so operation ofthe entire circuit will be necessary to startthe conveyor. In cases where the entirebelt conveyor cannot be seen from thestarting point, a positive, audible or visiblewarning device should be sounded by theoperator before starting. All employeesshould stand clear of the conveyor. Thisalarm is an important precaution where aseries of starting switches cannot be used,as in many underground mines.53. Emergency stop cables must beinstalled on the entire length of theunguarded conveyors. They also should beprovided at the drive and take-up ends, andat loading and unloading stations.Emergency stop cables should be posi-tioned so a person caught in the conveyoror having fallen onto the conveyor can eas-ily reach and activate the emergency stopdevice. A manual reset cable, extendingalongside the entire length of the belt, alsomay be installed for emergency braking ofthe conveyor.54. Overloading and spillage at transferpoints should be prevented, because over-loading may stall the belt and cause a fire,and spillage may result in injuries to work-ers. On all conveyor systems, where it ispractical to do so, electrical or mechanicalinterlocking devices, radioactive instru-ment controls, or both, should be providedto stop a conveyor automatically when theconveyor, bin, hopper, chute or other partto which it feeds has been stopped orblocked. The conveyor system controlsshould be electrically interlocked so if onebelt stops or fails, all the others will stop.55. Provisions also should be made forcutting out the automatic interlocks whenmaintenance is to be performed on a belt.Moreover, there also should be some wayto operate the belt separately at this time.56. Some conveyor belts are now manu-factured with imbedded condition sensors

that can monitor speed, alignment, rippingand other belt conditions.

Acknowledgment

This data sheet was revised by the Ce-ment, Quarry, and Mineral AggregatesSection, Industrial Division of the NationalSafety Council, 1121 Spring Lake Dr.,Itasca, IL 60143.

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Figure 9. To minimize free fall and dusting, droptubes contain falling material from belt and allow itto trickle out from ports opening just above thestorage pile.



Sources of informationAmerican Conference of Governmental IndustrialHygienists, Committee on Industrial Ventilation, Box16153, Lansing; MI 48901.—Industrial Ventilation.

American National Standards Institute, 1430Broadway, New York, NY 10018:

—Practice for lndustrial Lighting, ANSI/IES RP-7.

—Safety Color Code for Marking Physical Hazards,Z53.1.

—Safety Standard for Mechanical Power-Transmission Apparatus, B15.1.

—Safety Standards for Conveyors and RelatedEquipment, B20.1.

—Safety Requirements for the Textile Industry, Lii.

—Safety Requirements for Floor and Wall Openings,Railings, and Toeboards, A12.1.

Conveyor Equipment Manufacturers Association,152 Rollins Ave., Rockville, MD 20852.—BeltConveyors for Bulk Materials.

National Fire Protection Association, BatterymarchPark, Quincy, MA 02269.—National Electrical Code,NFPA 70.

Occupational Safety and Health Administration —Safety and Health Standards (29 CFR 1910).Available from the Superintendent of Documents,U.S. Government Printing Office, Washington, DC20402.

—Subpart D-“Walking-Working Surface.”

—Subpart O-“Machinery and Machine Guarding.”

—Subpart S- “Electrical.”

Mine Safety and Health Administration. Metal andNon-Metal Mine Safety and Health Standards (30

CFR Parts 55, 56, 57, 75, 77). Available fromSuperintendent of Documents, U.S. GovernmentPrinting Office, Washington, DC 20402.

National Safety Council, 1121 Spring Lake Dr., Itasca,IL 60143

—Belt Conveyors for Bulk Materials, Part 2:Operation, Data Sheet 570.

—“Conveyor Belt Safety,” Hyde, W. A. NationalSafety Council Transactions. Mining Section. 1956.

—Open and Closed Storage and Reclamation ofStone, Sand, Gravel or Slag. Data Sheet 703.

Swinderman, R. Todd; Goldbeck, Larry; Stahura,Richard; Marti, Andrew: Foundations 2 – ThePyramid Approach to Control Dust and Spillage fromBelt Conveyors. 1997, Martin Engineering,Neponset, IL.

Swinderman, R. Todd; Goldbeck, Larry; Marti,Andrew: Foundations 3 – The Practical Resource forTotal Dust and Material Control. 2002, MartinEngineering, Neponset, IL.

Copyright ©2007 National Safety Council.

All rights reserved.

Although the information and recommendations con-

tained in this publication have been compiled from

sources believed to be reliable, the National Safety

Council makes no guarantee as to, and assumes no

responsibility for, the correctness, sufficiency or

completeness of such information or recommenda-

tions. Other or additional safety measures may be

required under particular circumstances.

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