:F2M7 CORNELL UNIVERSITY LIBRARY iSTATE or NEW YORK DEPARTMENT OF LABOR AUAmr OFFICE HEW YORK OFFIpB THE CAPITOL J 24 EAST 28th STREET HENRY D. SAYER THE JNDUSTBJAL COMMISSIONER JUNE, 1922 Cornell University Library TH 7697.F2N7 1922 Engineering principles and practical dat 3 1924 022 801 272 ENGINEERING PRINCIPLES AND PKACTICAL DATA RELATING TO DUST AND REFUSE REMOVAL FROM WOODWORIIING MACHINES PREPARED BY THE PiyiSIOir OF INdOSITRIAL EnrGiEITE T&E BUREAO of RkEARCH AND CODES Previous Publications Concerning Occupational Diseases statistics of occupational diseases reportable by physicians to the Depart- ment of Labojr appeared in the quarterly Bulletin during the years 1912-1913 (numbers 50-56 inclusive). The annual report of the Defpaitmemt for 1920 summarizes reported eases down to Aiigusit of that year. Beginning with 1908, the annual reports of the Department have contained reports upon, and discussions of, occupational diseases in iJew York State. Included in these reports are accounts of the following special investigations of particular industries, together with proposed regulations for their conduct: Bakeries in Manhattan borough, 1909, pp. 88^99. Calico print industry, 1909, pp. 80-88 (this account appeared also In Bulletin No. 41). Cloak and suit industry in New York City, 1911, pp. 87-96. Felt hat industry, 1911, pp. 57-6T. Pearl buttons, 1910, pp. 93-103. Phosphorus matches, 1910, pp. 83-93. Potteries, 1909, pp. 100-112. Tlhe following special reports on ventilation have also appeared in the reports of the Department: Results of air analyses in certain factories, 1910, pp. 104-111. Results of air analyses in cloak and suit factories in New York City and in the felt hat industry, 1911, pp. 108-133. Ventilation of factories, 1908, pp. 65-94. Ventilation of a department store, 1911, pp. 63-86. Other material published includes the following: Sanitary conditions in the Printing Trade (82 pp.). Annnal Beport of Bureau oi Labor Statistics, 1906, pp. [xxi-cii]. Health of printers (8 pp.). Bulletin No. 33, 1907, pp. 258-265. An English Report on physical Deterioration (8 pp.). Bulletin No. 30, 1906, pp. 372-379. Special Rules and Regulations Adopted by the British Government for the Regu- lation of Certain Dangerous Trades (47 pp.). Annual Report of Bureau of I^bor Statistics, 1906, pp. 833-879. The Dangerous Trades in England (4 pp.). Bulletin No. 33, 1907, pp. 255-258. Poisoning by Wood Alcohol Fumes from Brewers' Varnish. Bulletin No. 51,iPP. 130-137. Also printed separately. Lead Poisoning Eliminated in a Factory (relates to protection against dust in the sandpapering of castings). Bulletin No. 54, pp. 64-70. Anthrax in Woolen Mills and Tanneries. Bulletin No. 56, pp. 402-6. Chronie and Lime Sores in Tanneries. Bulletin No. 56, pp. 405-6. Advice to Workmen for Prevention of Lead Poisoning (cards for distribution to workers, printed in English, German, Italian, Hungarian, Polish and Yiddish). How to Prevent Lead Poisoning (poster containing advice to workers in English and foreign languages). The Reporting of Industrial Diseases ( small pamphlet containing the reporting law, explanation of purpose of reporting, end lists of diseases and harmful substances). ' Eurppean Regulations for Prevention of Occupational Diseases. Special Bulletin No. 76 (77 pp.). Anthrax. Special Bulletin No. 79 (22 pp.). Hoods for Removing Dust, Fumes and Gases. Special Bulletin No. 82 (23 pp.). Dangers in Manufacture of Paris Green and Scheele's Green, Special Bulletin No. 83 (17 pp.). Dangers in the Manufacture of Industrial Uses of Wood Alcohol. Special Bulletin No. 86 (18 pages). Health Hazards of the Cloth Sponging Industry. Special Bulletin No. 89 (24 pp.). A Simple and Inexpensive Respirator for Dust Protection. Special Bulletin No. 90 (10 pages). A Plan for Shop Safety, Sanitation and Health Organization. Special Bulletin No. 91 (10 pages). Health Hazards of the Chemical Industry. Special Bulletin No. 96 (69 pages). Asphyxiation in Garages. Special Bulletin No. 101 (23 pages). Devices for Sanitary Control of Material Disengaged in Industrial Processes. Special Bulletin No. 102 (31 pages). Of the publicatione above referred to, files of which may be found in many public libraries, the Department can supply only the Annual Report of the Commissioner of Labor for 19019 and 1910, Bulletins 51 amd 54, reprints of tixe article oa wood alcohol in Bulletin 51, .th« cards and poster oomcerning lead poisoning, and special Bulletins 82, '8i3,,86, 90, 96, 101 and 102. FOREWORD The puri^osc of this pamphlet is to set foi'th the principles of venti- lating;' engineering, relating to dust and waste removal from machines used in the woodworking industry. It is addressed to factory owners, factory jiroprietors, eontractoi's, and ventilating engineers, who, having problems to meet for the removal of waste from woodworking machines, may be guided by seeing what others have accomplished along this line to attain the end of guarding such machines having dangerous revolving cutting parts, removing refuse and working in a clean shop, wherebj' the fire hazards and oper- ating hazards are reduced to a minimum. It necessarily is confined to the processes and machines which are in more common use, the illustrations relating to which, with some changes, may be made applicable to many other special machines. Helpful service has been extended by those who have permitted photo- graphs of various devices and conditions to be taken in their factories, from which the accompanying illustrations ha\-e been jn-epared, and to them our thanks are extended. HENRY D. SAYER, The Industrial CoDiinissioner. STATE DEPARTMENT OF LABOR Henry D. Saver, The Industrial Commissioner M. H. CiiRlSTOPHERSON, Deputy Commissioner THE INDUSTRIAL BOARD John D. Hicgins, Cliairman Richard H. Currax ilRS. Kosalie Loew Whitney Bureau of Inspection, James L. Gernox, Director Bureau of Workmen's Compensation, Kdirr. F. Colejiax. Director Bureau of State Insurance Fund, Leonard W. Hatch, Manager Bureau of Industrial Relations. SEA^fAX F. Northrup, Director Bureau of Research and Codes, il. H. Christopiierson in charge Secretary, Clarence A. ilEEKER Chief Statistician, Eugene B. Patton DUST AND REFUSE REMOVAL FROM WOODWORKING MACHINES Among- the industries of New York State, Woochvoi-king holds a place ot principal importance. In every city, and in many villages of the State, there can be found factories which ai-e enoaged wholly, or in part, in the sawing, dressing or shaping of lumber or wood during the process of which there is usually a large amount of waste material created. Since the time that industry in the State of New York fii-st developed, the production of raw buildin- material and articles of wood has been carried on. Wood, technically considered, is the aggregated tougher parts of the vascular bundles of seed and fern plants. Only the seed plants yield wood which IS of any value as lumber and among them nearly all W'oods of commerce are produced by conifers and dicotyledons ;' the mono- cotyledons produce but a small amount. In the latter class only the large bamboos and a few of the palms yield timber of any importance. Other divisions of plant life do not produce merchantable woods and are therefore disregarded in this connection. Wood consists of a ground work, oi' structurally of a sulistance known as cellulose, pei-meated by material collectively known as lignin. There e.xist also secretions within it such as resins, gums, oils, sugars, coloring matters, balsams and mineral salts which vary in amount according to lhe wood and its age. In the particular kinds named herewith are found certain acids, resins and alkaloids which is the cause of terming some varieties " ]ioisonous ", This pamphlet is prepared to serve as a guide for the construction of ventilating systems and de\'ices to be used in connection with wood- ■\voiking machines, and to remove waste material produced by them, i 'ndei' the term " woodworking " are included such industrial processes as log cutting, lumber cutting and dressing, cooperage work, cabinet making, pattern making, wood carving, the manufacture of household articles, ornaments, novelties, implements, house-trim, cai-penter shop Mork, veneer cutting-, and the manufacture of smoking jupes. Woods popularly known as iiiiie. ash, willow, hemlock, cypress, beech and birch contain no toxic pi'inciples so far as is known, which may be detrimental to health in tlie process of wni'king them, while sequoia ■wood, cocobola woorl, sabicu wood, satin wood, Mexican blue gum, Indian rosewood, African box wood, cokus wood, teak wood, ebony, and tagayasa contain substances of a poisonous nature. Dust, generated in the ■^vorking of these woods, if not properly controlled, produces illness in those exposed to it, for instance: *Workers in sequoia wood dust are liable to suffer from catarrhal symptoms such as sneezing, watering of the eyes, irritation of the throat and coughing, *C'ocobola wood dust produces inflammation of the eyes and skin. *Sabicu wood is said to produce snuffy dust and catarrhal symptoms of the eyes and nose. '"Tagayasa wood causes dermatitis and affects the digestive and renal functions, *Ookus wood, Mexican blue gum, teak and ebony dust is also liable to cause inflammatory skin affection. tAfrican box wood * Kober and Hant-on : Ilispasps r.f Orfnpatinri an([ A'ocy ticmal Hygipnf, pp. fi74, t TJiompson : Thp Or-nipational Discasps, p. 446. 13'] 4 New York State Department of Labor saA\'dust causes to those who first work with it, a smarting' of tlie eyes, dizziness and symptoms fesembling severe influenza. Persistent working with it causes suffering from asthma and cold sweats, due to the presence of an alkaloid. In numerous establishments, new wood is not always the material which is worked. The sawing, shaping and smoothing of wood which has been painted with jiigments containing lead in the form of hydrated carbonate, chromate or other form, or stained with solutions which con- tain sodium bichromate or certain dyes, or treated with ]ireservatives, such as creosote, disengage a highly poisonous dust which has been found by medical insjM'ctors attached to the Division of Industrial Il.vgiene to have caused in several instances occupational illness among those who inhaled such dust. The removal of dust containing all of the above substances, by properly constructed exhaust systems with nitakes capable of adequately catching all the dust at the place of origin, would prevent the occui'rence of illness to tlie operators. Sand drums, sand belts, sand discs and column sanders ai'e extensive!}' used in many branches of the woodwoi-king industry to produce smooth surfaces. These devices not only create a volume of wood dust which is soft and in a state of fine division, but in addition, a considerable amount of i)iorganic material composed of glass, quartz, garnet, corundum, aliindum and magnetite which is detached from the sand jiaper attached to tlie discs, drums and belt sanders. These ]iarticles are shai'p, angular and of irregular form, being made up of broken massive material, fragments of crystals or of both, the effect of which, when breathed, is to produce bronchitis, laryngitis and pneumonokoniosis. Therefore the removal of dust containing the objectionable irritants above referred to, should lie performed by ade- quate exhaust systems attached to the machines, as a means toward preventing the breathing of this material. The amount of waste material in the form of chips, shavings and sawdust thrown off from the machines naturally varies according to the machine, the size, I'ajiidity and manner of operation. The health hazarfl of the operators is one which results from the mechanical iri'i- tation to nose, throat, e,ves and lungs, foi' the reason that tlie material is soft and oruanic, excejit in the case of the dust created while wiu'king the woods heretofore named which contain ]ioisonous principles and of material disengaged from sand belts, sand drums, column sanders and disc sandei's. FIRE HAZARDS The presence of shavings mixed with chips of wood and sawdust, which can be found beneath oi- at the side of any woodworking machine, unless prevented from being deposited there by exhaust sy.stems, can be readily ignited by the careless throwing of a half burned match, tobacco sup- posed to be " out " or friction with " good matches '' carelessly drop]ied on the floor near points where the refuse lies or among it. AVood dust quickly accumulates on tops of beams, ledges, sills and I'afters in the absence of proper methods of removal at the points of origin when generated and can be readily disturbed by air currents through doors and windows or by vibrations throughout the build- ings. AYhen such dislodgment takes place, accumulated masses often Engineering Principles — Woodworking Machines 5 drop to the floor, on benches or machines where the presence of open tiame gas jets used for artificial illumination offers a means of igniting the dust. The fire spreads quickly and unless extinguished in its mcipiency may consume the structure. N(i. 1 — Carplcssnesw and thfi absence of an oxliauf^t .^.vHtem toi jjioiieih iinioMig Rud .storing waste material (sawdust, chips, .sliavings} caused tlie wilcI^, by tiii-, ol tlii^ factory. OPERATIVE HAZARDS Statistical records relating to accidents in connection with woodwork- ing have always been looked upon as indicating a special hazard. *The many varieties of work included in woodworking industries are among the most dangerous of modern employments. Machinery run at high speed whose cutting parts are sharpened to a keen edge, together with the difficulty experienced in guarding many of the moving parts, con- tribute largely to the accident lists in those places where woodworking machinery is used. The floor, made slipperj^ by constant usage and contact of sawdust with wooden flooring, on which an operator may slip or fall and in so doin''' come in contact with moving parts of the machines and become iniured, is of grave importance. This Rule 916 of the New York State Industrial Code aims to prevent. In this rule it is stated that " the floor where operator stands in operating machines, such as wood shapers, iointers and circular saws, must be provided with approved means of preventing slipping ". The danger of stumbling presented by mounds of sawdust and sticks which accumulate beneath and at the sides of machines in the absence of exhaust systems, is a condition which most anyone who has observed it realizes to be conducive to accident production. ^'•^^uTl^haak : Woodwortlng Safeguards, p. 7. Xo. - — 'I'l'iiniiHi- with oiH pipe tu cnlj \p\' ;(\\;iy Tile chip whirh (.hips anil liiist afi'\iiiiiil; hcail siuarded and tc which is altai-'iicd Ir ml and 4-in. li and dusr. St-^eoud In.'ad, nut I'nnipprd with rxlianst, in t't\ un II (Mir. i-()ndii(a\a-' to hrc an(i (ip:Tati vh hazai'ds. Pile sa wdnst remove. rcfnsp wliich ■p hazard and ( 11 int'ttVctiA-p exhaust system fa 11(^1 tu iTatnv hazard exists. Engineering Principles — Woodworking Machines 7 Economic plant management requires the speedy removal of all refuse accumulations. In the absence of automatic' and continuously operated refuse conveyin;.;' systems, the loss of considerable time, labor and expense is occasioned in shoveling up and conveying by hand the waste to some bin, chute, or receptacle usually located at some remote point. Without a means to remove the sawdust, chips, shavings and blocks from the machines, they often clog up and their etficiency is reduced, thus requiring frequent cleaning, resulting in a loss of the operator's time and a consequent increase in accidents. As the chips and dust east off from the cutting knives of the machines attain a high velocity, injuries to operators' eyes often result. Small particles cause eye irritation which dulls for a period of time the sight, and increases the likelihood toward accidents. Hoods to which pipes are attached offer excellent means to safely guard many of the cutting parts in connection with woodworjcing machines. It is advisable to make them adjustable by means of slip pipe joints which may be raised or lowered to the various positions necessary to completely guard the cutting heads. yeetion 299, Paragraph 2, Title 4, of the State Labor Law, provides that "All machinery creating dust or impurities shall be equipped with proper hoods and pipe-; connected to an exhaust fan of sufficient capacit.v and power to remove such dust or impurities; such fan shall be kept running constanth' while such machinery is in use. If in case of wood- working machinery, the board decides that such apparatus is unneces- sary for the health and welfare of the employees, it may adopt rules excepting such machinery from the operation of this subdivision ". For the benefit of those who are desirous of information relating to the construction of ventilating systems and devices for the removal of dust, shavings, chi]is and blocks, the following data should be noted as No. 4 — A 16-inch cirt'ular rip saw t*x- IjDsed to contact beneath table (violation o( .\ew York State Indnstrial Code. Rule 9015). Tiiei'e is dangi'i- from contact with the saw in the act of attempting to remove the sticks or sawdust lying on the floor be- neatii the workinsi' talile. 8 New York State Dej'artment op Labor essential in constructing a proper exhaust system to be attached to wood- working machines. The half-tones illustrate what certain manufacturers and engineers have accomjjlished in the State of New York in devising simple and effective means for the removal of waste from woodworking machines in their plants, which may in rnrmerous instances serve as a guide to others who care to Ijenefit by the eifort of those engaged in a competitive liiie of work. No. f) — Circular rip ^aw t^ucldsed on tlic UDtlpr side of the tal)le. The hopper is made of no. ■2t) V S Standard Gauge lletal to whieli is attached a 4 inc h ))ipe reading to a du'-t <'ol lector. A door in the side of the hopper otters a means to remove all and soeliet joints aboN'e letter "A" for oonvenientl.v adjusting pipes. SIZE OF MAIN PIPES AND FAN INLETS AND OUTLETS The area of a main pipe at any point should not be less than the combined areas of the branch pipes entering it between such points and the end of the system and the increase should be carried out propor- tionately throughout the entire length of the main pipe. AVhen long lengths of piping are used, they should be increased from 10 to 20 per cent in area greater than the combined areas of the branch pipes enter- in"' it. No more than two branch pipes should enter a main pipe of uniform area. Floor sweeps connected to mains need not affect the area of the main duct for the reason that they are but occasionally used. ARRANGEMENT OF PIPES AND CONSTRUCTION Every branch pipe leading from any machine or part of a machine should enter the main pipe at an angle not greater than 45 degrees, -phese branches should be inclined in the direction of the air flow at iunction with the main. Branches should not pro.iect into the main, and should preferably be located on the side or top of the main pipe, for the reason that if placed on the bottom of main they may interfere with 10 New York State J3epartjient of Labor the flow of material past the openings and even choke unused branches, acting as a trap into which the material may fall or lodge. Each branch pipe should lead out from the hood in such a manner that the dust thrown into the hood should enter the pipe at the point where tlie highest air velocity exists. Any main duct or discharge pipe should be as short and with as few bends as possible. Every bend, turn or elbow should be made with a radius in the throat at least equal to l^/o times the pipe's diameter on wdiich it is connected. There is no advantage in making the radius more than twice the diameter of the pipe. It is stated on pages 413 and 414, Vol. XVIII, 1912, Trans- actions of the American Society Heating and Ventilating Engineers, that A right-angle elbow in a 6-inch pipe offers as much resistance as a straight pipe of the same diameter 44 feet long. With a radius of half the diameter, it is equal to a straight pipe 15 feet long. With a radius of one diameter, it is equal to a straight pipe 5% feet long. With a radius of two diameters, it is equal to a straight pipe 21,4 feet long. By making the radius more than twice the pipe's diameter, the resistance begins to increase again until at six diameters it is equal to a straight pipe 3 feet long. This is due to the greater distance the air is under compression on one side of the pipe while making the turn." Wherever possible, all pipes should have a removable cap at the tail of each main or trunk line which will admit of easily cleaning the system. All laps joining sections of pipes should be constructed in the direction of the air flow. All horizontal seams and seams of elbows w^hich are double locked need no lapping. Pipes of 12" diameter should be con- structed with 1" lap ; those above 12" to 18" diameter should have IVi" lap ; those above 18" diameter to 24" diameter 1%" lap ; those above No. 7 - Elbow attached to a main pipe connected to sand wheels, constructed with a radius in the throat equal to 1% times the pipe's diameter. EXGINEERING PRINCIPLES — WOODWORKING MACHINES 11 -i" diameter should have 2" lap. All seams should be soldered air tight, and edge coated. All laps or seams should be riveted before soldering. Pipes of S" diameter should have four rivets. Above 8" diameter to 12" diameter five rivets; above 12" to 18" diameter six rivets ; above 18" to 24" diameter seven rivets ; above these diameters i" to 9" centers will suffice. Plorizontal seams when lapped should be lapped and riveted as above. Cleanout slides or doors should be provided at intervals of 10 or 12 feet to admit of branch pipes, suction main and discharge pipe being cleaned. All pipes should be either supported from beneath or suspended from above when necessary with wood, wire, strap iron, angle iron or bar iron at intervals of 15 feet to prevent sagging of the piping. The use of small turn buckles attached to wire rope offers a simple means of adjusting the pipes into which hoods with smaller size pipes telescope. All slip joints into which pipes of a smaller diameter telescope should have a reinforcing band on the outside of the larger member and be free from projections and sharp edges. Where flexible joints are used, the section should be so constructed that when bent to one side these sections should not withdraw from one another, causing openings and leakage. A length of pipe close to the fan should be macle up in the form of a slip sleeve, held together by straps so that it can be easily removed in case of necessity, such as clogging. j,jo 8 _ Clean-out slide in a pipe stowing guides "A" and "A", stop a and Handle " C ". No. 9 — Damper or blast gate show- ing casting in which gate slides. A chain attached to the gate prevents it from being entirely withdrawn. DifBculty is often experienced in maintaining a sufficient air velocity in lono- sub-trunk lines or branch pipes leading from remotely located machines to the main pipe to which the majority of machines are attached. 12 New York State Department of Labor On branches of pi-acticallv equal leno'tli there exists, if propei'ly pro- portioned, usuallv a uniform air movement throus'hout, while within the long- sub-trunk lines or branches of a much smaller diameter than the main trunk line a much lower air movement is maintained, lo over- come this difficultv, in the laving' out of a new system, the mam trunk line should be mo'ved to a point which will be central to all machines. When this cannot be done, it is simpler to f^roup machines which are remote, provide a main for them and use an additional fan, leading No. 10 — jNIetliod nf suspending piping into wtiieli pipe.^ attatlied to hoods telescopo. The suspenders are made of wire to which small turn buckles are attached to malt dust from suiul bells used No. 11 ^Exhaust **5";™/';"fA"' Th> piPiiig lavout is faiiU.v for the reason that automatically to jyUice toilet >,f.iu. - i ^ ^-^^^.^^ .^ ^^^ throats. The branches it has too many elbows construc^t.u^vw^ manner that the air currents strike each other, c^;;ing"a"heavrb?-l'r.res;nre, and .naking the systen. Ineffective. 14 New York State Departmen't of Labor DAMPERS AND BLAST GATES E\cTy branch pipe attached to a machine shoukl he provided with a l)]ast gate or damper of the sliding' type, arran^'ed with a stop to pnwent it being entirely I'emoved, or witlx a chain to prevent the slide from being thrown about and becoming lost. The use of slides is necessar}^ to shut off an}^ particular branch line when not in use which will increase the air movement in the remaining branches leading from other machines, and to prevent cold air entering the workroom ■\rhe]i the system is not in operation. This may be accomplished by placing an automatic damper in the piping: on the outlet side of the fan. It, of course, must he understood that a sufficient number of gates must at all times be left open when operating the exhaust system or an insuffi- cient quantity of air will be admitted through it. Two l^raneh pipes should never enter a main duct directly opposite one another. Junction pipes or " Y " branches should be constructed in such a manner as to offer as little resistance as possible at the point where the two air currents merge, thus reducing back pressure. In S3^stems where material is fed into a furnace, there should be an automatic fire stop gate, placed in the piping between the separator and furnace. GRINDING WHEELS Exhaust pipes attached to grinding wheels on which tools or other material is ground or sharpened should not be attached to the pipes of an exhaust system conveying wood dust, chips, or shavings, for the reason that fire may occur within the system by the ignition of the wood dust, chips and shavings from the incandescent particles thrown off in the process of grinding. SIZES OF BRANCH PIPES The sizes of branch pipes attached to woodworking machines are for the most part a matter of experience depending on the maximum A'olume of material to he moved. For the more commonly used machines the following sizes have been found to work well and these are recommended TO be used. The symbol '^ is used for " inches " throughout the following table. Self Feed Table Rip Saw. Up to 16" diam 4^-" pipe on bottom. Greater than 16" diam 5" pipe on bottom Large Self Feed Rip Saws Other Than Table Sairs. Wet Lumber S" pipe on bottom SwiuQ Saii'S. Up to 12" diam 3V' pipe Over 12" diam. to 20" diam. Over 20" diam 4^" pipe Rip saws Table Saws Mitre Saws Up to 16" diam 4" pipe Over 16" diam. to 24" diam. . Over 24" diam 5" pipe Variety Saw With Dado Head 5" pipe pipe on top pipe on top 5" pipe on top 4" pipe Variety Saws ■ A\" pipe Up'to''24'' diam Over 24" diam. to 36" diam. Over 36" diam. to 48" diam. Over 48" diam Gang Rip Saws 5" pipe on bottom. Q" pipe on bottom, 7" pipe on bottom , 8" pipe on bottom . 4" pipe on top 4^" pipe on top 5" pipe on top ■5j" pipe on top Up'to 12" diam Over 18" diam, to 25" diam. Over 32' diam. to 33" diam , Disc Sanders 4" pips Over 12'' diam. to IS" diam. 5" pip3 Oi'-3p 2;)'' diam, to 32'' diam. 6" pipe Over 3S" diaii. to IS' dlan. 4^' pip 3 Sj" pipa 7'' pip3 Engineering Principles — Woodworking Machines 15 Triple Drum Sanders Less than 30" long 6" pipe 30' to 36" long 7" pipe ipe from the hood or opening, to iiroduce a difference of level of at least two inehes of water between the two sides of the " V '' shaped tube, excejit for those machines which re(.(uire higher air velocities. The test is made by ]ilacing one end of a rul)ber tube over a small hole drilled in the liipe, the other end of the tube being connected to one side of the " U " shaped water gauge. A test should be made with all branch ]npes open. It is essential that some opening or openings be left in the building to allow the influx of outside air, as a partial vacuum is produced within a closed building by the operation of any vacuum movement ventilating system. Engineering Principles — Woodworking Machines 17 COLLECTORS The collection of refuse in the form of sawdust, shavini^s, chips and blocks after removal from the machines is essential on account of the larue volume produced. il of supporting it by an angle iron framp, advantageous " position ot clean out caps and good incline of discharge pipe to refuse bin. 18 New York State Department of Labor The sizes given are not proper for all lines of work, for the reason that fine dust re((uires larger separators than the collection of shav- ings, chijis and l)loeks. The collection of fine wood dust is difficult to accomplish with the centrifugal type of separator wherefore the tubular or screened tj-pe or the air washer are better adai)ted for this purpose and are advocated to be used in connection with cyclone separators to catch and confine the larger particles. Every collector should be made of metal of not less than No. 20 gauge. It should be constructed in a manner to offer the least resistance and back pressure to the incoming air. Pipes entering a collector should do so in the form of a rectangle; means should be provided to clean the body of the separator, conical end and discharge pipe or pipes therefrom. Supports for separators should be of a substantial character, capable of being fastened to the roof or other part of the structure when neces- sary. The point of discharge from any separator or collector should be located so that the discharged air therefrom will not enter any window, door or other opening of the building. Particular attention should be given to the size of vaults or receptacles for refuse, taking care to have them large enough to hold the entire amount of waste material created in a day's work. Diameter Area of Diameter Diameter Outside Height Length Gauge of fan Size of inlet inlet in of air of dust diameter of of of metal outlet in in inches square outlet outlet cylinder cone to be inches inches in inches in inches cylinder in inches in inches in inches used 6 4 X 10 40 10 4 36 16 42 £0 S 5 X 15 75 15 6 48 21 54 20 12 7 X 22 154 24 10 66 30 72 20 16 9 X 30 270 28 10 78 36 82 20 IS 10 X 32 320 31 10 84 38 90 18 20 11 X 36 396 36 11 94 46 98 16 •■*2 11 X 38 418 39 11 98 48 101 IS 24 11 X 45 495 44 11 106 52 109 IS 26 12 X 46 552 46 12 110 54 112 18 28 12 X 52 624 62 12 118 60 122 18 30 14 X 54 756 58 12 126 66 128 16 32 14 X 59 826 64 13 134 72 135 16 34 15 X 61 915 67 13 13S 75 139 16 36 15 X "0 1 , 050 73 14 146 82 146 16 Note. — It should he distinctly understood that the above table is produced merely for the convenience of any one who ma>- wish to refer to it. PLANS *Plans in triplicate, or drawings made in ink to scale, or prints of scaled drawings and specifications should be filed with the Department of Labor for approval before installing or making any alterations in any exhaust system. On these plans should be shown' the location of machines, sizes of pipes (whose dimensions should be indicated as being inside measurements), gauge of metal, size and location of collectors, size, make and capacity of fans showing inside dimensions of inlet and outlet, location of cleanouts and caps at tail of system, position of blastgates, sizes of hoods (where possible to give tliem), the name of machines to which each branch pipe is attached, and the air velocity to be maintained in the system. See Title 4, Section 299, Paragraph ::>i: the Xew York State Labor Law. Engineering Principles — Woodworking Machines 19 The following- illustrations show etfective constructions, which may serve as a guide to those who desire to apply their principles to the various problems they encounter. ^Q 1^ Collectors having revolving elbows which turn by the action of the wind. Resistance is reduced as the discliarged air is expelled in the direction in which the wiiui is blowing. Note rectangular entrance of pipe to collector and method of sup- porting angle iron frames in concrete. Nn. 14 — -nond in position. No. ]r> — Hood cast back to shriw knives. Auto- mati<- wood turning lathe equipped with exhaust, having an 8-inoh pipe for the removal of the chips. The hood "A" acts as a substantial guard which can be raised or adjusted for the removal of the knivi's and articles being turned. \^'r^§'smTm 2so. lt( — Du\etai!er, equi[iped with hood and pipe for removal of shavings. Hood measures 7 inches in width, 14 inches in length, 27 inches in height. Pipe connection is 5 inches in diameter ; 4 inches static suction is maintained in above installation. No. 17 — Dowel machine, with 4-inch pipe attached to casting of machine. opening on which is provided for the conntrtion. An air movement of 4005 feet per minute, 2 inches static suction, is sutiicient for the purpose of chip conveyance. No. IS — Hat block sanding lathe, equipped with a hood to prevent chips fronr being cast on floor during operation. Note hopper on bottom, to which is attached branch pipe through which a high movement of air travels, (.5,6.50 feet per minute equivalent to 4-inches static .suction). Xo. 10 — Jointer — pro- vided wirli a hupp'?!' and lipe attached to exhaust systpm for conveyance of wa^te from the mji chine. Tlie hopper, though in- tended to catch the chips thrown olf from the cut- ting hend, fails, for the reason that the machine is not properly boxed beneath the knives allowing shav- ings to fall on the floor. No. 20— I'ower auger — equipped with lateral hood and pipe for removal of chips thrown off while drilling holes. The pipe attached in this case is 4 inches in diameter, through which a velocity of air of 56"i0 lineal feet per minute is maintained. The suction is high in order to catch the chips thrown off on the off-side of the auger. No. 22 — Clothe s-pin lathes, to which are at- tached exhaust sy.^tems, using 5 inch pipes as branches. The hoods at- tached to the pipes are arranged on hinges, itpr- mitting adjustment to re- ceive the chips and dust at a point whnri- the highest air velocity is maintnined in the pipe. In the above case 8 inehos static suc- tion is mjiintained. No. 21 — Tcnoner equipped with ex- haust hoods which adequately protect the cutting tools. The brancli pipe attached to the hood is 4 inches in diameter. A 4-inch static suction is maintaim d within the branch pipe, which is necessary in order to lift the chips from the cutters. No. 23 — Sbapiir — to which is attached a 4-inch pipe and rectangular hood. The ball aud socket joint, also the telescopic slip joint, allows the pipe and hood to be adjusted to the work. Note long sweep elbows, method of entrance of branch pipe into main, also junction pipes attached to the branches, in which, according to the principles set forth herein, friction of air in the pipe is reduced to a minimum. An air movement of 52S6 lineal feet per minute, equal to 3^2 inches static suction, -was main- tained in the above branch pipe, which successfully removed the waste from the knives. No. 2-1 — Vibrating spindle-sander equipped with exhaust, having a 4-inch pipe attached. A high air velocity is neces- sary in this pipe to at- tain successful results on account of the lateral air movement to draw in the dust di.?engaged at the spindle; 3 inches static suction was maintained in the pipe, which made the device successful for dust removal. *«*fcfc ^'4'A<#1«- »^ -• \ f^C^.«^*^ r^ "^"^ iSo. _3 — Iwuhead btiokcr — lu this ease and for the remainder of the machmps on this floor, the main suction pipe is near the ceilinj^ of the floor b^low, \a hern other woodworking machines are located. Note the " return bend " of branch pipe to flcior below. Such a connection means serious loss in efficiency through resistance and friction in multiplied bends and elbows. Individual systems and fans on each Hoor would have saved money in cost of power with an equal degree of efficiency. Note the cut-out portion in the pipe used as a floor sweep, designated by the arrow. A shut-off damper is provided in pipe. A high velocity of air movement is necessary at the nozzb^ intake if succes.-iful results are to be obtained. In the above case 4 in._-ht-s static suction (5.6.j0 lineal feet per minute) was maintained. No. 2b — Effective exhaust system applied to drill presses for chip removal 3-inch' pipes used as branch pipes. Air velocity of 5650 lineal feet per minute (4 inches- static suction; is maintained within the branch pipes. K^^i "■■'" / ' i . J 'Jf^^-^':-*^.-- "/ Bfl i (^^^■^■■nKAB^^^^^BHl^XKl -^^^^M No. 27 — Hood and branch pipe atlaclied to a pony planer — hood measurement being 6 inclies wide by 26 inches long, 20 inches high. The hood effectively covers the knives. Xo 28 — fhain mortiser with e.xhaust tor removal of chips and wood dust. As' the waste must be lifted, although partially assisted by the chain on its up travel a high velocity of air movement is required successfully to remove It. In the Tbove case I inche" .static .suction (5650 lineal feet per minute) was maintained in the branch pipe. No. 29 — A near a four-sided moulder view showing hood and branch pipe connection to three heads of It i.s defective in that the connection of tbe branch pipes to the „ ...v.. ^.v.v,. .^■..^...^.. It ].s detective m tnat the connection ot tue Drancn pipes to loe hoods, for side heads, should have beon made with a radius in the throat IVs times the h ■ninp diameter of the branch pipe. No. oO^ Effective hoods and exhnust on lathes used for tnrnius- and forming smok- ing pipes. 3-inch pipes are u.^ed as branch pipes, in whirh an air velooitv of 400o lineal feet per minute (2 inches static suction) is maintained. Note main pipe 'located beneath machines but not lying on tbo floor wbich admits of cleaning: the flodr. ■ equipped with exhaust for cliip and No. 31 — Automatic hat blocli turning lathe - dust removal, in foreground. The hand-turning lathe seen at the right-hand side and back of the automatic hat block turning lathe is equipped with a bench sweep marked marked " E." Exhaust .systems cannot advantageously t)e attached to account of the length of articles turned. The most effective method for waste material removal is t' floor, the full length of the lathe, covered with a grating through which thechips can fall. A piping connection can be provided with openings resembling floor sweeps beneath the grating which will admit of cleaning the pit. The bench on which the lathe is attached should be provided with openings, grating and exhaust pipe as described similar to floor openings. "A" and a floor sweep hand-turning lathes on provide a pit in the No 12 — Effertive hoods and exhaust system attached t(. lathes and discs used for fonmiife^ faiiioking pipes. An air velocity of 4u05 feet per minute is maintained in the bran* hi s oi the system corresponding: to - inches static suctinn. Nu. oo — Multiple drill — LMjuipped with liluw nozzle at the left >;ide and collecting hood at the right side. The chips and dust are blown from talile into the hopper through which an air movement is maintained of 1000 feet per minute through the cross sectional area at its mouth. Note good engineering principles displayed in pipe con- struction, i. p., I'lbo^vs have radius of l^l- times diameter of pipe, blast grates have chains. No 34 — Panel lai^-pr equipped with exhaust having a Ci-inch pipe. The hood attached to pipe measures 5 inches wide by 6 inches in depth by 16 inches in length. A high air velocity is re- quired to convey the chips in the above case : a 4-inch static suction is main- tained. No. 35 — ^ Bed planer — equipped with exhaust. Pipe attached to hood is tele- scopic ; note blast gate in pipe, collar around large section of pipe for stiffen- ing and method of supporting by means of wire and turnbiickles. Xo. 86 — Log saw equipped with exhaust above and beneath the table. These hoods guard the saw at both points. To each hood is attached pipes for the conveyance of sawdust to a collector. The hood above the table is adjustable for various sizes of lumber. Saws up to 60 inches in diameter are used in connection with this machine. The device is eminently effective for dust removal. 2 inches static suction is maintained in the pipes. No. 37 — Drag saw — used for log cutting — no provision being made for removal of savi'dust. A pit covered with a substantial grating could be constructed beneath the saw, extending beyond both sides of the rollers. Exhaust pipe could be attached for con- veyance of sawdust as it falls into the pit. No. .38 — Five-foot diameter traveling carriag.^ saw equipped with an exhaust system. The hopper beneath the saw is lorati^d under the flooi-, as shown in the toliowlng illustration. No. :VJ — Hoppor beneatli carriage saw In connertirm with r>receding illustration, into wbich the sawdust from the saw, 'Is cast. The pipe attached to thi.^ hopper leads from it at a right angle. Faulty construction at tliis point, in not having made the pipe of a sufHcient .size (0 inches in diameter) and leading it from the hopper having a radius of lYo or 2 times the pipe's diameter, caused the constant clogging of the pipe and hopper and necessitated the installation of the clean-out "A", to empty the hopper when full of sawdust. The entire device is thus ineffectivi'. No. 40 — Swintr cut-off saw — showing hopper bt^noath table attached to pipe which leads to fan and collector. The hopper, about r, inclirs wide and of a length at its top equal to the length of travel of the saw, can readily catch the sawdust thrown off by the saw when operating ; 2 inches of static suction, equivalent to 4005 lineal feet vif air movement per minute, is ample velocity successfully to convey the sawdust to the point of collection. Nos. 41 and 42 — Travel- ing cut-off saws, each bav- ing 6-inch branch pipes leading from the bottom of the cast iron frames or hoppers, which constitute effective guards for the saws. A high velocity of air must be maintained in .^uch branch pipes, by rea- son of the remoteness of the saws from the branch pipps at certain stages of operation. In the above installation a static suc- tion of 4M2 inches was maintained in each branch pipe, which effectively re- moved the damp sawdust thrown off from the saws. No. 4y — Exhaust system connected to a re-saw. This construction could be bet- tered by entirely enclosing the lower wheel, in which case the exhausting volume of air generated in thp branch pipe would have to be exhausted through smaller spaces. This would cause a higher velocity of air at the saw blade where the dust is created. At present only the sawdust which falls by gravity into the hopper is removed. The balance permeates the workroom atmosphere and finally settles on fixtures of the room. No. 44 — Shinple saw — havinq: lateral exhaust by iiieaus of a 6-inch pipe placoi] at a point to catch the sawdust thrown off. A velocity of air of 56'50 foot per minute equal to 4 inches static suction was maintained in the pipe, as the moveiTient of the waste ly a lateral one. No. 4.0 - — 1 )rum saw — containing ten (10) circu- lar saws on one shaft. The hood at top is d feet long by in inches wide. which ■effectively ?;uards the saws and removes the sawdust through a pipe 12 inches in diameter. Hop- per marked " B " receives the equalized cut wood parts which are convoyed to other parts throvigh pip-es. A cover was rp- moved from hop])er to show saws. 40 — Door en( lo--ing lower wheel No. 47 — Door enclosing lower whe^l open. closed. An efficient method of removing dust from a handsaw. Note the hopper beneath the table, which becomes a tightly enclosed box when the front board is in place. A suction pipe is attached to the end of this box from the main suction pipe of the exhaust system for the floor beneath. The blade of the band saw passes through the box to the lower wheel with a minimum clearance. Air from the 2 inch pipe shown by arrow above the table blows the finer dust, which is not carried through the table by the saw blade, away from operator. Compare this with the following plate which shows a defective exhaust installation on a band saw. No. 4S — A bandraw on wliich the exhaust is almost useless. The point of entrance, shown by arrow, of the ex- hausting volume of air is located at the farthest possible point from place where the dust is created b.v the saw. Multiplied turns and bends exist in the branch pipe between the connection to the handsaw and the main suction pipe. Door enclosing box of lower wheel was opened to show entrance or intake of s.vstem. No. 49 — Barrel head turner. The hood "A" is designed to cover opera- tion of head and saw. The hood at- tached to the pipe measures 16 inches square at bottom by 24 inches in height. Xo. .30 — Disc sander — .3 feet in diameter. Simply a wooden wheel to which sand- paper is glued, equipped with hopper beneath the rest, which encloses the lower half of the disc wheel. The pipe, 5 inches in diameter, leads from the hopper to the main. As the surfacing of the article is in most cases done at the sector of the wheel on Its down-travel, half of the sector of the wheel could advantageously be enclosed on its A 2-inch static suction maintained in the branch pipe, corresponding to 400.5 lineal feet per minute, effectively removes the dust from the above wheel. X,, -,i — Self-leeil rip saw, to wliitb is atta'-liprl n-inch ))iiif. Tin/ [niint fni- adjustment, also slip joint .lud inetlioil (d staMn^ pipe witli «iii Xn. ."il* — lleadins jointer fnr iiarrel nnuhiues. Kni\'es are eneased ill cast iron fr.aiiie. A 6-illeli pipe, shewn Ity arrow. renie\-es the waste to the colleetor. No. 53 — Sand disc — used for surfacing inner parts of wooden liat blocl;s. The iron band "A" and back *' B " causes the dust to form a vortex and with rapid air movement through the pipe " C " all dust thrown off is readily removed. A 4-inch static suction (.5650 lineal feet of air movement per minute) is maintained in the branch pipe. Sn. .".4 — I'.iluiiin saiider — showiiiK Kiianled disc lapnlile "!' bciu;; lowered furtlier tban sbown, which acts as a collector for the detached abrasive from the revolving disc and the fine wood dust removed from the article being sur- faced. , ^ ^ Two pipes attached at the top of the collector "A" form a junction into one branch pipe ?,V2 inches in diameter. The pipe on each arm is swiveled. the whole offering no obstacle in the operation of the machine. An air velocity of 400.3 lineal feet per minute maintained in the branch pipe successfully removes the dust from the work. No. 55 — Horizontal sand belt having exhaust re- motely located from point of contact of the belt with the article being surfaced. Note the failure of the device which can be cor- rected by following the principles for catching the dust illustrated in the half-tone below. No. 5S. No. oij — Belt Sander — equipped with extension pipe for exhaust as a means to catch and re- move abrasive and wood dust disengaged at the TKtint of origin. This pipe being telcsciipic can be ndjusted to a point where the dust is given off, namely where the work is performed. High air veloci- ties are necessary, above 4 inches static suction, suc- cessfully to catch all the dust disengaged. 36.30 lineal feet per minute, cor- responding to 4 inches of static suction, is main- tained in the above instal- lation. No. 57 — Vertical saud belt — to whicli is attached a 5-iDch pipe at bottom in the casing ot the machine for conveying dust from the machine. A static suction of 2 inches, corresponding to 4005 lineal feet per minute, maintained in the pipe, suc- cessfully removed all dust created. Sl^ intA f^and hU^k. b*>f Sa/)tf»i' Hood inctBand a x ^a fi^ b-i 1 t'a^v t in am Ata and n»e«»4*.ry /-(./To^o «f flu/Z^u $00 c r /^. Ov V trfrpa ■ lititfcl ft air s.' pt> .V Y St^f. Bureau .f In^f^^-h, J^i^ 8" njii. No. 58 — The principle involved i.s to retain the exhausting volume of air generated in the branch pipe at a point as near where the dust is created as possible, and then exhaust .such air volume through a restricted opening. The result is a high velocity of air that will actually picl? up and remove the dust at its point of origin. Belt Sanders are in use 20 feet in length. Usually a hopper-like hood connected to a suction pipe i.s placed between the end of the table and the right-hand idler. The sanding process mav be four feet or more distant from the hood, and since the air volume maintained in the 'suction pipe has been entirely dispersed in the enlarged open mouth of the hood and intervening air space the results are negative. The above sketch shows the possibility of u.^ing extension pieces which may be either set in at " C " or made capable of being pulled out when the exten.sion piece is telescopic. No. 59 — End yIhw of piiclosure tif auto- matic sanding Litlie. (jl — Mud \]p\\. .uitimalK sandmg lathe. Cu\ er raided. No *',(i — ( ippratnii^ opi nmg ol pik lo uiH ot autoniatu -^anding latlit* Nu < udinii Automatic brusli sanding latlie entirely eneloserl in a dust-tight l)Ox, except for the operating opening, and equipped with an exhaust system. Excessive dust created by this machine made its operation a serious prolilem before this dust removal apparatus was installed. As sh()~riisc Sanders — usn] in thr manufacture of smokiny; pipes. Thi' hoods art' faulty in that the opeuinss ctiuld linve t)i'eu restricted. This nipiins tlint a higher air velocity must be niaintaine{l in tlic hraucli pipes tii create a sufficient air intake through the hoods. H-inch brunch pipes are used in the aln)Vi' installation. Note main pipe suspended so as to admit of (Icaniiitj: the floor. No. B7 — Horizontal spindle routers used in nmnufacture of shoe lasts, eipiijiped with exhaust system. Kxhausting volumes of air cause a partial vacuum in each hood sufficient to retain all dust ami refuse until they are removed by the exhaust system. Xo. fix — Three drum horizdutiU sandorK equipped with exhaust (upward movement). ;; inches statie suction was maintained In the pipes for movement of material disengaged from the drums. No. ('•'■> — Threi'-headed automiitic gainer, showing one of three heads having u hood for dust removal marlied ''A". This hood attached to the cutters i-; connected to the reguhir exhaust system, in con- nection witli other ma- chines on the samp tloor. Note the .shavings and dust on this floor as a result of the inadequate means of dust <'ontrol. No. TO — Doulde-hi'iidpd ti'noner and eq\ializer used in connection with tenon- ing wagon spokes, c\ltttng them at the same time to ■ e(iual lengths. Note thit because the air moviMiient in the exhaust pipes is too low, waste material falls on the floor which should he drawn into the pipes, which in the above case ai'c 4 inches in dianuifer. No. 71 — Double-edge rim rilaner used for planing or rounding rims of wagon wheels. Th(- hood above table thoroughl.v covers the knives. Pipe leading from xmderside of table, having a slip .ioint, is arranged to be readily disconnected, as also the pipe attached to the hooil above the table. The deyice is effective as a means ol' removing waste. Xo. 72 — An automatic gang saw and mill wliicli saws and ojipns a shoe last for use as a shoe tree, pquipped with exhaust for removal of clust. Note flexilde jriint at "A", aluminum hoods connected to an exhaust system which act as substantial " guards for saws and mill, sheet metal guard over saw at " P> ", and ruliher mat in front of machine to prevent t slipping. • Rule HO.T. New Yorlc Ktate Industrial f'ncle. t Rule 916. New York State Industrial Code. Noti tlirrnigh 7'> — Thp sniiK ;;iiarf] " V* ■iilW - - hdlKl (1 smile iiiiicliiiie ;is in ]vrrci'tIiDy illiisti'ntioii. rl ;iutnniati<-;illy hy t;nidt' rdfl " (.' " pni to allnw (■hay;;inj: of saws. tn allow shor last tr Engineering Principles — Woodworking Machines 47 While the foregoing illustrations are in no wise complete, nor is it urged that the good examples shown could not be improved upon, it is hoped that sufficient information has been conveyed to enable factory owners and engineers to contrive hoods or devices for special machines or construct different types of hoods for particular classes of work. With the nucleus thus offered upon which to work, it is hoped that greater improvements can be anticipated for the near future resulting in more efficient exhaust systems. BIBLIOGRAPHY National Workmen'* C'omnensation Service Bnrea\i : Safety in WnonwoRKixr, New Yorl< City. ButTalo Fortje Company: Fan Enginekking. . Bnlfalo, N. Y. National Safety Coiiiwil : Woodwork] kg .Machinkry and Kqi'ipmunt. Safe Practices Pamphlet No. 20. Chicago, 111. Thompson: The Occupational Disea.se.s. D. Appleton and Company, New VorU and London. 1>914, Kober and Hanson: DiSE.\.SE.s ov Occupation and Vocational Hygiene. P. Ulack- iston's Son & Co., Philadelphia, Pa. l!Hfi. Perry: RiSK.s AXD D.VNGER.s OE V.\Rious Occupations. Scott, (Treenwood & Son, London, Hayhnrft: A Si'rvey of Induktrlu. Health-Hazards ,\nd OrrucATiONAi, Dis- EAsE.s IN (iHio. Ohio State Board of Health. Colnmhiis, O. IDlo. New York State Denartment of Labor: The New York State Labor Law. Ifl21. Albany. N. Y. New York State Denartment of Labor: The New York State Indu.stkial Code, 19r20. Albany, N. Y. Ra.mbouf ek ; iNnu.STRiAi, Poisoning. Kdward Arnold, Loiidcm. 1913. New .Jersey State Department of Labor: S.\.nitary and Kngineering Inditstriai. SiAND.iKDS. Trenton, N. .1. 191!). Van Sohaack. Woodworking Saiegiards. .J^'tna Life Insurance Company. Hart- ford. Conn. 191,3. Transactions of the .American Society of Heating and \'entilating Enginec-rs. Vol. XVni, 1912, In addition to tlie references listed above, material on this sidjject will also he found in the pamphlets, bulletins and catalogues of the principal firms engaged in ventilating and fan engineering. Special Bulletins of the New York State Departmeat of Labor / -'■-■■ year 1914 - ..^ ■.;:'■ , .,■ ' No. ,&7. Idleness of. Organized Wage Earners' oil September 30, 1913, (7' pages). Out of print. Idleness of Qrganized Wage JSarners in 1913 (53 pages). Qui of print. Digtet of the New York Workmen's Compensation Law (21 pages) ; Out of print. ;'■;"-,.,.'■■■ • , . (Kevieed). The Workmen's Compensation Law (47 pages). Out of print. Statistics of Trade Unions in 1913 (145 pages). Out of print. Idleness of Organized Wage Earners in tbe First Half of 191^: (16 pages). New York Labor Laws of 1914 (100 pages). Out of print. Dlreotofy of Trade IJnions, 1914 (104 pages). Out of print, i Chang;es tn Union Wages and Hours lin 1913 (116 pages)., Out of prihi. Union Rates of Wages and Hours in 1913 (186 pages). Out of print. Strikes' and, Lockouts in 1912 and 1913 (139 pages). Out of print. InteTnationai Trade Union Statistics (24 pages). Out of print. Statistics of Industrial Accidents in 1912 aiid 1943 (175 pages). ,(iut , of print. \ ' ' , ~ , -1 . '"-'':' ' ' , . 'Year lijis, ., Idleness of Organized Wage Earners in 1914 (41 pages). Out of print. New York Court Decisions Gbnoernlng Labor Laws (118 pages). Out of ■: ' print. ' ■ , , ;' •',',■ ■';•■"", GoTernment Labor Reports, October, 1913, to May, 1915 (29 pages). New York Labor Laws of 1915 (67 pages). • , , Idleness of Organized Wage Earners in tli'e First Salf of J9l5 (16 pages). Statistics of Trade Unions in 1914 (146 pages). , , , Statistics of Industrial Accidents, 1914 (77 pages) . Out of print. European Regulations for Prevention of Occupa1:ional Diseases (77 pages). , Out of print. Industrial Accident Preventibn (54 pages). .New York Labor Laws of 1916 (98 pages). Out of print. Anthrax (22 pages). Out of print. ' Year 1917 Fatal Accidents Due to Falls in Building Work (26 pages). Court Decisions on Workmen's Compensation Law (406 pages). Out of print. :• , •.,',,, ' , ' Hoods for Removing, Dust, S^m^s alid Gases (23 pages). Dangers In Manufacture of Paris Green and ,,Scheele'8 Green (15 pages). New- Yolk Labor Law's of 191,7 (63' pages). bourse of Employment in New, York State, 1904-1916 (30 pages). Out of print. ■ ' '■ , , '- ■ , No. 86; Dangers in the Manufacture and. Industrial Uses of Wood Alcohol (18 . pages). ' ■,■-.,■, I V --■ Year, 1918 ,'■' No. 87. Conrt Decisions on Workmen*s, Compensation Law (394 pages). No. 88. New York Labor Laws' of 1918, (7l pages). ' Noi 89. , Health Hazards of the Cloth Spon^ng Industry (24 pagfes). Out of print. No. 90; A Simple and Inexpensive Respirator for Dust Protection "(10 pages)., Year 1919 NOi 91. A Plan for. Shop Safety, Sanitation and Health Organization (32 pages). - Out, Of print, , , , ,' ,."Nd.''92; Weekly Earnings of Women in Five Industries (21 pages). No. 93/ The Industrial Replacement of Men by Women (69 pages), No. 34. New York Labor Laws Enacted in 1919 (72 pages). No. .95; Court Decisions on Workmen's Compensation Law (402 pages). /No. 96. Health Hazards of the Chemical .Industry (69 pages). : Year 1920 tSo. 97.. Court Decisions «n Workmen's Compensation Law (278 pages). No. 98. Court Uecislons on Workmen's Compensation Law (114 pages). No. '99. New York Labor Laws Enacted in 1920 <93 pages). No. 100. The -Telephone Industry (95 pages); No. 101. Asphyxiation in Garages (23 pages). \ ';,.,'! Year 1921 No. 102. Devices for Sanitary Control of Material Disengaged in Industrial ,, r , Proce^es (31, pages). . -'■-/■'' No. 103. Court Decisions on Labor Law attd Industrial Disputes (200 pages). -No. 104. Industrial Posture, and Seating (56 pages). Out of print. No. 105; Flint Disability Funds (Ifi pages). Out of print. No, 106. Court Decisions on Workmen's Compensation Law (302 jpages). 'No. 107. New York Labor Laws Enacted in 1921 (6S pages); , ' No. 108. SijCkness Among New York State Factory Workers in 1919 (29 pages). No. 109. Employment of Women In 5 and 10 Cent Stores (08 pages)., '- .Year 1922 '," No. 110. 'Wbmen Who Work (40 ifagesi); ' No. m. New York Labor Laws Biia.ftea in 1922 (38 pages). No. 58. No. 69. No. ■59. No. 60. No. 61. No. 62. No. '63. No.' No. ^■, No. 66' No. 67. No. 68,. No. 69. No. 70. No. 71. No. 72. ,\No. 73. No-. 74, No. 75. ;no. 76. No. 77. No. 7S. No. 79; No. 80. No. 81. No. 8i. No. 83. No. ,84. No: 85.