Document 6JrznD1XdGDm3ny79Xayq8MR

FILE NAME: Mine Safety Appliances (MSA) DATE: 1954 DOC#: MSA011 DOCUMENT DESCRIPTION: Trade Journal Article [A 2nd Look at Welding Hazards] & Advertisements 3, Po77O N Editor-in-Chiel ALFRED M. BEST Editor H A R R Y De G. A R M A N D Associate Editor RALPH P. E A M E S Editorial Assistant D A V ID K. SILVER New Products Department E D W A R D S. H O F F M A N Managing Editor CHESTER M. KELLO GG BUSINESS DEPARTMENT Executive Vice President ARTHUR SNYDER Seles Manager W ALTER H. B R O C K H A V EN Production Manager A. M. CRO W LEY Publication Office: Columbia Turnpike, Rensselaer, N. Y. Editorial and Advertising Offices: BEST Building, 75 Fulton St., New York 3S, N, Y. NATIONWIDE BRANCHES WESTERN FRANK J. MATRE, Seles Mgr. 10 South La Saile Street C H IC A G O 3, ILL. EAST CENTRAL PAYSO N H. RYAN, Vice-President FELIX T. M cC a r t h y , Jr., Spec. Repr. ARTHUR A. EBERLE Ingalls Building, 6 E. 4th St. C IN C IN N A T I 2, O H IO NEW ENGLAND WALTER A. SPANGLER, Manager W. LAW REN CE HOWE, Spec. Repr . 13 Stanhope Street BOSTON 16, MASS. EASTERN ELLIOTT SEWARD, Spec. Repr. FRANK W ALDRON, Spec. Repr. 75 Fulton St., New York 38, N. Y. MIDDLE ATLANTIC H O W A R D J. ADER, Manager 1208 Nelson Street R IC H M O N D 26. VA. SOUTHEASTERN 22 Marietta Street ATLANTA, GEORGIA SOUTH CENTRAL GENE H ANSELM ANN, Manager ISI Lynda Drive C H A T T A N O O G A S. TENN. SOUTHWESTERN ROBERT S. BEGIEN, Manager ROBERT S. BEGIEN. JR. OH 8 Gas Building, St. Paul Street DALLAS, TEXAS PACIFIC COAST H A R O LD F. KANE, Manager HSO Wilshlre Blvd. LOS ANGELES 17, CAL. Copyright, l?54 Alfred M. Best Company, Inc. 75 Fulton St., New York 38, N. Y. Annual Subscription $4 (two years $6 Canadian & foreign $5 (two years $8 Single issues 50c. Also quantity rates SflfT9 i mflifmnflnci moDucTion FORMERLY "SAFETY ENGINEERING" EST. 1901 VOL. 108, NO. 4 OCTOBER, 1954 EDITORIAL The Safety Specialist .... .. . . . .................... 9 National Safety C o n g r e ss ...................... ....................... 9 ACCIDENT PREVENTION What Have the Plant Engineer & the Safety Engineer in Common by A. B. PETTIT 21 A Second Look at Welding Hazards ..................... by PAUL C. Z IE M K E 22 Molten Metal Miracle .................................................................. 25 A Non-SIcid Floor W a x ........................................... by C A R L L A M M 28 Making Grinding Wheels Behave (machine guarding series) . . by C. E. HARPER 44 What You Must Know to Guard a Machine-- Part 2 by W. E. M O N T G O M E R Y 48 Keeping Up With Emergency Lighting ............................................ 83 New Safety Products................... ... ........ 94 Free Safety Bulletins..................... ................ . . ....... 99 MAINTENANCE A New Floor W a x .............. .. ............. . by C A R L L A M M 28 Western Maintenance S h o w ...................... . ................... 30 Keeping Up With Emergency L ig h tin g .............. .......... 83 New Maintenance Products........................ .......... 94 Free Maintenance Bulletins.............. . . . . . 99 INDUSTRIAL HYGIENE Clean Water for "Gandy Dancers" . ... . ............. 7. .. Industrial Hygiene N e w s ...................... .................................. The Need for Proper Wound Care of the Injured Hand (first aid series) byDR. R A Y M O N D M. CURTIS Industrial Hygiene Data Sheet-- Trichloroethylene.............................. The Coffee Break-- Boost or Bust? ....................... .................... The Industrial Nurse .................................. New Hygiene Products.................... . . . Free Hygiene Bulletins . . .. . ... . 35 65 66 69 71 73 94 99 FIRE PROTECTION A Second Look at Welding Hazards ..................... by PAUL C. ZIEM KE 22 The Fire F ro n t............................................................................ 55 Fires Mean Inspection Failures (fire protection series) . .by A L A N L. K L IN G 56 ' Clean Up Dry Cleaning & Degreasing Fires ... .by N O R M A N H, DAVIS, Jr. 60 New Fire Products...................................................................... 94 Free Fire Bulletins............................................................... 99 SPECIAL DEPARTMENTS . Safety's Supermarket (Exhibitors at National Safety Congress) . . . . 4 Check List of Aids to Production . . ................................. 12 The Future S h o w s.............................. . . . . . . . . 14 Inside the T ra d e ............. ... . ., . . 16 The Safety S h e lf..................... . . . . . . 32 A Safety Illustration............. .... . .41 Learning the Hard W ay ....... . . 76 What's the L a w .............. .7 7 Safety Achievements .................. . . 79 Transportation Safety ................ . 88 Safety on F ilm ........................................ 90 What's New in the Safety-Maintenance Field . .......... .'.......... 94 Free Bulletins & C a ta lo g s .............................. 99 Reader's Free Inquiry Card ................................. . 99 Index to Advertisers ... .............................. . 100 COVER PICTURE By courtesy of Humble Oil & Refining Co. A ME R I C A ' S PI ONEER MAGAZI NE IN ITS FIELD SAFETY M A IN T E N A N C E 1 PRO DUCTIO N is indued regularly by Engineering Index, Inc., Ne York : r ' -V i ' V. To get a greater return for your eye safety dollar... As a natural result of the continued efforts of Safety Directors to reduce eye accidents, more and more workers are wearing industrial safety pre scription glasses on the job. In a growing number of instances, however, ar rangements have not been made to take full ad vantage of the complete services of the professions to verify the lens properties of these glasses, fit the glasses to the worker and maintain them in proper adjustment. As a consequence, safety standards have been jeopardized in some areas, through the use of flam mable non-safety frames, -- or lenses of question able impact resistance. Tragic, unnecessary, and costly accidents have resulted. American Optical Company believes that correc tive-protective glasses should reach the employees only when adequate professional services are pro- vided. 'Such a procedure is a sure and effective way to combat the breakdown in safety standards. In some states, this procedure is required by law. Corrective-protective glasses made by American Optical Company meet all safety requirements, Super Armorplate lenses carry this mark (AO) in* dicating that they are heat-strengthened and comply with rigid specifications for thickness and impact resistance. Frames are made of corrosivo resistant metal or non-flammable plastic and are sturdy enough to withstand use under normal working conditions. They also carry the AO trade mark. The employment of the full cycle of professional services in connection with prescription safety glasses and the standardization of AO lenses and frames will assure maximum protection for the worker and the greatest return for every dollar in vested under your supervision in visual safety. Be sure to see our film, Room 5 2 4 A , Conrad Hilton, at the National Safety Show. American O ptical SAFETY PRODUCTS DIVISION SOUTHBRIDGE, MASSACHUSETTS BRANCHES IN PR IN C IPA L CITIES (For details, use Key # X -l on ca rd on p a ge 99) Keep your worker* in the Safety Zone with American Optl* col Safety Equipment ! rom 5 products to more than 3600 x. A 40 Year Record of SERVICE TO SAFETY Keeping pace with safety needs has been our job here at M.S.A. since our beginning on June 14th, 1914. During these years, hundreds of new hazards have been introduced by new industrial processes and projects. Many of these problems were antici pated by us . . . many were relayed to us. The more than 3600 items now in our product line provide ample testimony to the fact that our extensive re search and manufacturing facilities were successful in finding the right answers. Our finest reward for these 40 years of safety service comes from the knowledge that today thou sands of men, who otherwise could be seriously injured, are well because M.S.A. products have turned accidents into incidents. This knowledge is a spur to continuing achievement. MINE SAFETY APPLIANCES COMPANY 201 North Braddock A ve nue , Pittsburgh 8, Poi At Your Service: 7 6 Branch Offices in the United States MINE SAFETY APPLIANCES CO. OF CANADA, LTD. Call the M.S.A. man on your every safety problem Toronto, Montreal, C algary, Edmonton, W innipeg, Vancouver, Sydney, N.S. . . . his job Is to help you Representatives in Principal Cities in Mexico, Central and South America Cable Address: "M IN S A F " Pittsburgh FOR O C T O B E R , 1954 (For details, use Key # X-12 on card on page 9?) 15 CHECK THESE WESTINGHOUSE HORIZONTAL SPEEDHEATER SPECIALI) Plate fini f noise, mlnlnilH coil clogging | greater efficiency. The trad ition al v a lu e in unit h e a te rs-- for instant h e a t* q uiet h e a t low -cost h e a t Built for strength, built for style, built to install easily and satisfy for years. For today's outstanding heating value, look to a pio neer name in unit heaters--look to Westinghouse 'Speedheaters ! Check, before you specify, all the fea tures that add up to traditional Speedheater superiority : (1) instant h e a t -- generated at the flip o f a switch, . and all of it effective heat because the Speed- heater one-row, plate-fin heating element assures most efficient heat flow; , (2) quiet heat-- the Speedheater, always known for silent operation, is quieter than ever! Aluminum plate fins, mechanically bonded, cut noise . . . rugged, welded construction eliminates rattles . . . powerful die-formed fans send heat where it's needed, do it quietly; (3) low -cost heat-- heat that saves dollars on fuel (up to 25% savings in present installations over old-style systems), more dollars in pure-andsimple efficiency in heating spots or large zones, in supplementing central systems in any required pattern. Check other Speedheater values, too: the pliable steel hanger straps and flexible connection combinations (see cuts) that simplify Horizontal model installation . . . the multiple-cone diffusers on Downblast model that give positive heat control, especially desirable for buildings with high ceilings . . . the all-purpose AGAapproved Gas-Fired model that eliminates the need for central system heating. For full information call your Westinghouse-Sturtevant heating specialist now. Or write: Westinghouse Electric Corporation, Sturtevant Division, Hyde Park, Boston 36, Mass. WESTINGHOUSE AIR HANDLING ..youcansi sure...if.a W estin gh ou se----------- -- 20 (For details, use Key # X07 en card en Rage ff) SAFETY MAINTENANCE & PRODUCTION 1 Ar c a n d g a s welding is indis- sec that the machines get an occapensable to industry for speedy sional trip to the shop for the more production of a host of products complete electrical check, that could not be efficiently pro- Perhaps the most important item duced by any other means. Not only on the list of welding equipment is is the technique invaluable for pro- the electrode holder. Some men are duction work but for maintenance quite happy with an uninsulated purposes it certainly is a godsend holder, and argue that the insulato the harried plant engineer con- tion material is too fragile and therefronted with some new breakdown fore cannot be depended on. The problem each day. Paint is scaled off fact is that the insulated holders can with ease, case hardening is done in be depended on if handled carefully a jiffy and large pipe is heated in and inspected at frequent intervals, place for those intricate bends re- Statistics indicate that a large perquired to fit into congested places. centage of accidents are chargeable W hile all this is on the profit side to uninsulated holders or those that of the ledger, there is also some con- were in a defective condition, cern over the hazards presented. Most accidents of this type occur Badly kept gear can injure workers in cramped quarters where the weldthrough electrical shock, flash burns er's body is wet with perspiration to the eyes, and burns from spurting and is in liberal contact with the slugs in heavy cutting operations, work piece. Quite often any contact W elding equipment therefore must the operator may make with live, be kept in good condition, and the current-carrying parts through wet or inspector's job is twofold: He must bare hands will not harm him serimake detailed, periodic visual in- ously. But the shock he receives spections for defects; and he must may cause him to react with such force and reckless abandon that he is injured in other ways. The common expression "kick like a mule" is no exaggerated expression. For direct current does act like that. The most vulnerable feature of electrode holders is the head, pro truding beyond the ring or collar of the insulating material just above the hand. That portion lacks insula tion. As the worker changes rods, he may readily make contact with bare metal. If he should roll on the holder, or carry it over his shoulder as so many men do, the live part may come in contact with the neck or face. Grounding Hazards One type of arc welding careless ness that recurs frequently is the utter disregard for good ground or negative return connections to the generator. Literally miles of good 3-conductor power cord to electri cally driven tools have been ruined 22 SAFETY MAINTENANCE S PRODUCTION cause of the inadequate physical con make contact with conducting ma nection between the aforementioned terial. 2. Carry the electrode holder By PAUL C. ZIEMKE services. Use of the structural steel frame of a building for grounding should be attempted only under the in your hand, not crushed under the arm, or slung over the shoulder. 3. Don't carry the holder about with direction of competent electrical a rod in it. 4. Don't work alone in Eye protection always gets supervision. confined places where a bump on Finally, there is the lazy man who the head, or metal fumes may knock first attention in Welding knows just enough about the mod you out and help may be slow in ern 3-phase lighting service to utilize getting to you. 5. Exercise particu safety. Let's look at some of the installation for his own benefit. lar care in high places where it is Like the individual who coupled his foolhardy to cling with one hand the other, less obvious haz negative return to the fire hydrant, while welding with the other. Use this fellow connects his negative standard staging material and don't ards: cable to the neutral wire of the 230-- stand on barrel heads or packing 115 volt lighting service and then ex cases to reach a high place! 6. If The Electrode Holder pects to move about the building you must work from a ladder erected anywhere with trailing positive cable in a doorway or aisle see that you Grounding of Equip ment to perform weld jobs wherever the occasion demands. This is a par ticularly dangerous practice since the have a helper at hand to guard against passing traffic. 7. Do wear the special chrome tanned leather Storage of Cylinders heavy current may heat the splices jacket, and keep your pants bottoms and connections on the neutral wire out of your shoe tops or you will Fire Hazards to the point of failure.. get a "hot foot" that won't be funny. W hat this man fails to take into consideration is. the fact that the Fire Hazards Dust and Fume Haz ards large, ample sized wire he couples onto in the building's service en The Livonia fire of the General Motors Co. rated the biggest loss for trance does not of necessity extend a single production unit, all because all the way out to his weld site in of an error in planning the protec , the same size and capacity. The tion needed against flying slugs of large size neutral wire extends only hot metal. Portable extinguishers because the welder used a makeshift to the individual lighting distribu merely halted the fire momentarily, is high-resistance ground on the work tion panels. From that point on, the and then it raged speedily out of n wire size is drastically reduced in piece. The heavy weld current, seek control before the arrival of the city keeping with the type of service sup fire fighters. In fact in most plants o ing a low resistance path, courses plied. The average "home run" wire :t over the third (ground) wire of the using much arc welding or gas cut electrical tool to burn off the drill leading to lights and receptacles is practically a standard--#12 gauge. ting apparatus, the fire runs made to extinguish hot metal slug fires far )>f binist uploatiinotnainndtoparatcotticaal llloyss".cook" the To weld on ventilating ducts, stacks outnumber those of any other cause. rf and conduit racks under such con Field welders, too, develop serious Potential fire hazards should all be re fire hazards by neglecting to bring ditions means that small conductors eliminated before welding or cutting a are annealed or burned off. in a ground wire to every job. An is begun. There are many ap S, all-too-common, yet dangerous, prac Create in the minds of the weld proaches to this. Probably one of :h tice is connecting the generator to ers a healthy respect for electricity, the most effective procedures is the e an outside hydrant or building sill- even though the voltage is consid issuance of a welding and burning er cock for the ground return circuit. ered too low to be deadly. A para permit before work can commence. rt W elding is then attempted in any mount warning to operators should T he operator asks for this permit :k part of the building on the general be to take special care in hot, humid from the department head for whom premise that there is sufficient weather and when welding in wet the work is to be performed. It is metallic interconnection between places. Almost without exception, he who is best informed on the haz water, gas, and metal sewer lines, fatal shocks occur in hot weather. ards peculiar to his department and The operator's physical condition plus the metal structure of the build therefore is best qualified to make all ss- ing, to form a low resistance path and the condition of his clothing arrangements to have combustibles he back to the generator. T hat this is should be his guide. blanketed or moved, floors watered or not always true is borne out from the down if of wood, and all flammable he number of mysterious fires that de Precautions for Welders gas producing equipment shut down od velop in service tunnels, attics and 1. Use care in laying down your and vented. If the nature of the in Ti basements where arcing occurs be- electrode holder so that it does not stallation warrants it, the depart- ed f O R O C T O B E R . 1954 3N mem ucau muse appoint a rename monitor to watch the operation for the full time the work is in progress. Armed with a suitable extinguisher he should remain at the welding site about a half hour afterwards to watch for any vagrant slugs that escaped his notice while the work proceeded. Failure to do that re sulted in a 2 million dollar fire that raged for two days in a warehouse. Oxygen and acetylene hose should be inspected and pressure tested every 60 days and no one but the authorized shop individuals should make up the connectors of the suit able right and left hand threads. Patching is ruled out at any time. Tape, no matter how well applied, never made an acceptable seal. It merely covers up a bad situation that leaks gas to fill a room with an ex plosive mixture, or permits the hose to catch fire as the leaking jet of acetylene contacts a spark. Usually, it's only a matter of seconds before the jetting flame bums through the adjoining oxygen hose and then the welder had better sprint fast for the Oxygen cylinder that exploded beceuM of exposure to heat and softening of lead teal. 24 regulator valves. The burning rub ber and the incomplete combustion of the acetylene can literally fill up a room with floating carbon, like a "black" snow storm. In one Tennessee plant the oxygen hose burst with such violence that it caused the rupture of an ear drum. The rigger who was cutting struc tural steel had run the pressure on the regulator up too high and was using the torch valve to control the pressure in balance with his acety lene supply. In another instance, a gauge exploded violently blowing out all the windows from the little repair shop, and peppering the work man with fine bits of pulverized glass from the gauge bezel. The cause? Someone unfamiliar with the hazard of the reaction between oxygen and oil flad used the stand ard shop gauge for calibrating the controls on a hydraulically powered elevator. The very legible inscrip tion on the white face of the dial --"USE NO OIL"--apparently meant exactly nothing to that benighted soul. But for the shield ing effect offered by the bulk of the oxygen cylinder, the shopman would . have been killed by the flying shrapnel shot oqt from the exploded gauge. Rupture Disks and Fusible Links One of the accompanying pictures shows the need for proper storage for all compressed gases, especially the fuel gases. The cylinder had been stored on the westerly side of a warehouse where the full rays of the summer sun beat down on it all the day long. Later, the cylinder was brought indoors to the small storage room adjacent to the shop. At the new location no overexpo sures to heat occurred, yet suddenly the storage room door was tom from its hinges, carrying with it the door frame stops and the strike plate. A close examination of the cylinder by experts in the field of compressed gases revealed what appears to be a logical sequence of events. T he ex posure to high solar heat on the outdoor platform had so softened the fusible lead plug on the safety cap that the lead extruded from the recess against the rupture disk. This slow movement of the lead caused the disk to flex and partially fail, yet the oxygen was still obstructed by the lead seal and hence did not es cape to the atmosphere. However, at some moment when the cylinder stood chained to its stanchion in the auxiliary warehouse one extruded portion of the lead seal let go and the rupture disk then failed com pletely, producing a jetting stream of oxygen downward on the ferrous metal threads of the protective metal cap and its associated swaged-on collar. At 2,300 lbs. pressure the escap ing oxygen reacted speedily with the excellent reactive material formed by the admixture of fine rust particles and the residual fatty materials left after years of smearing the valve threads with soap suds to check for tightness of gauges and fittings. The speed and effectiveness of the reac tion is indicated by the fact that an area the size of a silver dollar was heated to incandescence through three thicknesses of metal. The weakened metal was then forced up ward with the violence of a small volcano to splatter oxidized ferrous metal over the upper warehouse wall surface where several incipient fires were kindled on wood cross mem bers. A fire was also kindled on the wood plank which formed part of the chaining arrangement at mid point of the cylinder's length. This fire bears out the theory that the first reaction occurred as the jetting oxygen burned through the cap and collar, and so softened the cylinder wall that it failed under pressure. A check with experienced ware housemen discloses the fact that on many occasions they find cylinders completely exhausted as the result of this slow heating and softening of the lead seal above the rupture disk. The copper disk then develops a minute opening where its outer edge bears against the sharp shoul der of the valve tee to permit a slow, sometimes completely noiseless, re lease of the 400 cu. ft. of gas. While the Interstate Commerce Commis sion requires these two protective features on all cylinders to safeguard (Confimiod on pago 86) SAFETY MAINTENANCE & FRODUCTION 2nd Look at Welding (Continued from page 24) them against violent rupture in cases of fire or other exposures to unwar ranted high temperatures, the user of compressed gases should not trust to luck too long lest a serious acci dent occur. One can imagine the calamity that would have resulted if this cylinder had ruptured when con nected to an oxygen tent providing some patient the life saving features of oxygen therapy. Dusts may be defined as solid particles of matter which are ordi narily produced by grinding, crush ing, drilling or blasting, plus the chipping or brushing of welds. These materials may be carried about the welding shop and into other work areas unless point-ofoperation or first class general ven tilation is provided. The size of the particles varies from what is called ultra-microscopic to those which are visible. From a hygiene standpoint, the significant particle size of dust ranges from a fraction of a micron to 10 microns. (A micron is 1/25,000 of an inch). The most fre quently encountered dusts in indus trial shops are of inorganic minerals. Fumes may be defined as solid particles which arc formed by proc esses similar to combustion, conden sation and sublimation. The most common types of fumes encoun tered in industry are usually caused by the oxidation of metal, such as the oxides of lead or zinc. Particle size is usually smaller than that of dust and ranges below one micron. In contrast to dusts, fume particles tend to join together very easily. Many people erroneously speak of fumes when they mean vapors of liquid materials, such as acid solu tions, organic solvents, and the like. Fumes are usually found where mol ten metals such as lead, zinc, and cadmium are being processed or used in industrial operations. W eld ing may produce fumes of the metals which are being welded or fumes and gases from the variegated coat ings of weld rods. One costly FOOT ACCIDENT could have paid for 1000 PAIRS of W OODEN SOLES Reece has a shoe or sandal to fit your needs. See them at BOOTH 115 They are Puncture Proof REECE W OODEN SOLE SHOE CO. Dpt. SM-10 Columbus, Nebraska (For details, us Ky # X-53 an card an page 90) It should be remembered that metals may produce both dusts and fumes, according to the nature of the operation and the state of the materials when processed. For ex ample, among the heavy metals, such as lead, dust may be of equal or greater importance than fumes as a causative factor in disease. Other mineral dusts and metallic dusts that are also considered of etiological im portance are: (a) toxic and/or irri tant dusts (from heavy metals and their salts, such as arsenic, lead, manganese), and (b) fibrosis-pro ducing dusts, such as free silica and asbestos. Exposure to a potentially harm ful material is not necessarily a health hazard. It depends on the state of the material. W hether it is an actual health hazard can only be determined by an industrial hygiene engineering survey, in which the amount and kind of exposure is rated, according to accepted stand ards of concentration, size, and quality of dusts and fumes. Many persons erroneously state that there is. a "lead hazard," for example, when it is only known that con tact is being made with lead. 1 he importance of air contamina tion will be evident when it is real ized the pathologic effects produced by dusts and fumes are brought about almost entirely by inhalation. There is one outstanding exception, the absorption through the skin of lead in the form of tetraethyl lead, which is of course a fluid. No dusts, so far as is known, produce any systemic pathological conditions from skin absorption, and it is doubtful that any kind of true fume is absorbed by the skin. From the etiologic point of view, particularly with reference to patho logic effects, the following outline shows how different types of sub stances among the dusts and fumes act on the various systems in the body to produce pathological effects. The lists arc not complete; just typi cal examples are shown. (a) General system poisoning: Ar senic, lead, mercury, vanadium. (b) Substances acting on the gastro intestinal system: Antimony, 86 SAFETY MAINTENANCE & PRODUCTION cadmium, lead, mercury, zinc. (c) Substances acting on the skele ton and joints: Lead, mercury, ' mesothorium, phosphorus, ra dium. (d) Substances acting on organs of special sense: Arsenic, lead, manganese, mercury. (e) Substances acting as fatal poisons: Lead, mercury. (f) Substances acting on the genito urinary system: Arsenic, lead, mercury, vanadium. (g) Substances acting on the brain and nervous systems: Arsenic, lead, manganese. The name, "Metal Fume Fever," is applied to the condition which results from breathing fairly heavy concentrations of freshly formed metallic oxide fumes, principally zinc and one of its alloys, brass, al though the condition may result from the inhalation of other metallic oxide fumes. Metal fume fever is not a systemic poisoning, but it should be borne in mind that some of the metallic fumes that cause it, such as lead, cadmium, mercury, and manganese, may also cause systemic , poisoning. The symptoms come on some hours after exposure, usually after leaving work. The first sign is a dryness of the throat, which may be followed by a dry cough and a feel ing of heaviness in the chest. Rise of temperature, accompanied by sweat ing, and leucocytosis and elevation of the pulse rate and the blood pres sure follow, usually with chills. The symptoms ordinarily pass in 12 or 24 hours and the usual experience is that the employee returns to work the following day. A natural immu nity is conferred on certain types of workers, but the immunity seems to be lost rapidly after removal from continuous exposure. For ordinary conditions in which only limited dusts are encountered along with a fume condition, simple filter type respirators will protect the welder against the hazard of breath ing these dusts and fumes. The filter is made of chemically treated filter paper or felt through which the air is inhaled. The particular type of filter em ployed will depend upon the kind FOR O C T O B E R , 1954 Noite It,-- ,,,, safely signal! Nail mills, boiler fac lories, shuttle rooms no longer pres ' sent a signalling problem, Forget NOISE! 27S BEACON RAY The warning beam of light from this Beacon Ray will penetrate through any noise levels! Rotating through 360 this concentrated beam will reflect off any bright surface to warn the unwary even though they may be facing the other way. With or without audible signals in service a Beacon Ray with The warning beam of light from this Beacon Ray will penetrate An audible signal will fail to do this. Write for full details on the new low-cost Federal 27S Beacon Ray warning light. FEDERAL SIGN Formerly: Federal Enterprises, Inc. 8731 SOUTH STATE STREET and SIGNAL C o rp o ra tio n CHICAGO 19, ILLINOIS im a HutArnViOW lH>r d e ra ils , use Key # X-54 on c a r d on p a g e ? VI Another SCIENTIFIC INDUSTRIAL Safety Suggestion! FLEXIBLE STEEL INSOLE SAFETY BOOT Note the special safety features of this boot . . . designed for rugged use under wet working conditions. Sizes b to 13. Available, in Plain Toe Knee Boot and Steel Toe Safety Boot. SOFTSPON&e m ois ONLY ONE ITEM IN Asbestos Gloves Canvas Gloves leather Gloves Plastic Gloves Rubber Gloves Rubber Aprons TH IS COMPLETE LINE Rubber Boots Rubber Shoes Earvalvet Finger Guards Protective Clothing W iping Cloths n em iisrea SCIENTIFIC INDUSTRIAL SUPPLY CO. 2956 S. Varnon Ave,, Chicago li, III. Sae Us at the National Safety Congress BOOTH 303 CFor details, use Key # X-55 on card on page 99) of contaminant present in the air. Since it takes less of the more toxic materials such as lead to affect the wearer than the harmful amounts of fibrosis producing dusts, a more effi cient filter will have to be used against toxic dusts than against fibrosis producing and nuisance dusts. T h e ' United States Bureau of Mines tests respiratory protective de vices against various air contami- nants under carefully controlled con ditions. Devices meeting its tests receive that Bureau's official ap proval, and this is indicated by ap proval numbers on the device and a reproduction of the certificate on the package. Equipment approved by the U. S. Bureau of Mines for the particular contaminant or class of contaminants in the air should be used. Pictures by courtesy of: T op--Kaiser Services; Botton--U. S. Atomic Energy Commission. 87