Document 7RkVwwXO9RX7aGxGawjzx5MeV

1 THE !NSUSTrUAL.COMMISSION.OF.^OHlO- division or 8Amr'/usD . 700 wurr third avtmux COCUMSUS. OHIO UIX .August 31. 1972 Hr. Robert Porter Manager of Engineering Foeeco, lac. 20200 Sheldon Rd. Goreland, Ohio LL1L2 Dear Hr. Porter: fticlosed are two copies of a report on the visit made vo toot cocqparry on August 16, and 17, 1972. It vas a pleasure to Beet with you and Messrs. Staff, Adams, Haussan, and Ghose and the courtesy extended was very much appreciated. If this Division can be of assistance to your ccapany at any time on industrial hygiene or engineering problems relating to safety, please let us know. Very truly yours, ~7Zf //n+sz<i*, Robert V. Hursh, P.E. Industrial Hygiene Engineer Jlcp ... . . .. #i >-''* " Cy* * y ' * r*~`w' fc*. ' * igSAFETY:.DIRBCTOR,,t all Ohio iodastry - FOSECO 2034 /j rj-' 'kx - THE INDUSTRIAL. COMMISSION OF OHIO DIVISION OF SAFETY AND HYGIENE TOC WUT THIRD AVXMUt 'CDLUMDUS. OHIO AMIJt ' 4-2S70 4IMIM MM1 . wum August 31, 1972 cayyjS-SJt.JTTreusn Bet Pococo, Inc. 20200 Sheldon Bd. Cleveland, Ohio 4U1U2 1* Oq August 16, sad 17, 1972, a visit was Bade to the above company to Investigate possible health hazards from dusts and other materials. This visit had bees requested by the company. 2. Those contacted were: Hr. Robert Porter, Manager of Engineering Mr. Vayne Stoff, Manager of Industrial Belatious Mr. David Adaos, Corporate Personnel and Industrial Relations Manager Mr. Henry Hausman, Engineering Technician Mr. Pro Quae, fiigineer 3> The company manufactures hot tops and headings systems Tor steel ingot molds, and setallurgical chesicals Tor metal Belting and foundry industries. 1* The locations investigated are indicated as a layout of the plant, a copy of which is enclosed. 5. Mineral and fiber uterial were mixed at Location #3 in a row of vertical cylindrical blenders. Operators worked on a platform about 6 ft. above the floor. To measure asbestos fibers, a sample of air was taken os a 1" HI 1H pore aembrane filter with an ejector vacuum pump, for examination with a microscope. The indicated level was C.l fibers per milliliter of air, (f/ol), which is well below the present Threshold Limit Value (TLV) of 5 f/rnl and the proposed TLV of 2 f/ml. 6. For dust measurement, a sample of air was taken for 66 minutes with a Mines Safety Appliances Co. (>CA) Gravimetric Sampler. This samples respirable particles, having a cyclone which rejects those larger than 10 microns in size. By weight measurement, the indicated concentration was 6.9 milligms per cubic meter (mg/>r). This is S s * ? t. y t iV t -^SiVBTY DIBBCTOR" t all Ohi* industry non uuu 1n (T FOSECO 2035 "I " 'below the TLV of 10 afor inert particulates. A suitAble sample or settled dost * not be gathered for analysis of free silica content. The formula for TLV.of dust containing silica (Si02) is 10 afj* TL7* Jt si02 Zr respirable dust in mg/)r The foraulae in rarioua units are listed on page 18 of the 1970 TLV list, a copy of which is enclosed. As an example, at 100 SiO-,, the TL7 would be 0.098 mg/n . " 7. A dust sample was taken in the sane location with a midget liquid lmpdnger and later examined with a microscope, a method which has been employed as a standard by this Division. The Indicated level was 0.73 million particles per cubic foot (mppcf), which is below the TL7 of 30 mppcf fcr inert particulates. The TL7 formula in these units is TLV - % * l6 mppcf At 100 Si02, the TLV uld be 2.7 mppcf. Even if this had been the ease, the measured concentration was less than the TLV. With this method, the indicated level was a lower proportion of the TLV than that from the gravimetric sampling. If there had been some material soluble in the Isopropyl alcohol used in the impinger method, this might account for some of the difference. However, in recent measurements of mineral dusts at other locations, the gravimetric method has indicated a higher fraction of the TLV. The impinger method does not indicate a hazard at this location in the plant. 8. There was no exhaust system to remove dust from the area of the blenders. The measured 100 feet/minute (fpa) air velocity was from a pedestal fan at the south end of the platform. Host of the dust is released when bags are cut open and the contents charged into the tops of the blenders, the lids having been opened. An exhaust system with ducts connected to the upper back portions of the blenders could assist in drawing dust in through the lid opening of each blender. A useful source of design data is the book "Industrial Ventilation--A Manual of Reeonended Practice", available at $5*00 from the American Conference of Governmental Industrial Hygienists, 1011 Broadway, Cincinnati, Ohio 45202. * * i s 1 1 1;i Il .i 9. It was observed that, at the blenders and other dusty areas, the operators used approved respirators. 10. An impinger measurement of dust was made at a machine bagging "Pernue" exothermic material. Of the two machines at Location #4, this was the machine to the south. The indicated level was 4.0 mppcf, which is below the 30 mppcf TLV. The operator used a respirator. A 5" diameter . exhaust duct inlet was about 2* from the stream of flowing granular material. Air velocity at the breathing zone was zero, but was 6000 fpm at the duet inlet. Closer proximity of the exhaust inlet to the flowing material could reduce dust concentration. FOSECO 2036 11. An impinger measurement wu Bade during the airing of Ferrux 345 exotherm material in a double--coco gtizer at Location /9. The n iji line location was about 6' south of the door of the easternmost enclosure. Dust was leaking frda this uixer during rotation. The indicated. level was 5.6 ppcf, which is below the 30 nppcf TLV for inert perticulates. It was stated that workers use respirators when in this area. 12. Measureaest was Bade at the enclosed base of a silo containing ball gtit dust at Location #8 for ammonia which Bight be produced by the nitride of that mixture in the presence of aoisture. Using a Citigawm indicator tube, there was no indication. A moderate odor resembled that of calcine carbide. This enclosure is not e normal working area. There was no indicated hazard. 13. Measurements were Bade during the processing of Holdeote material containing zircon, which is zirconium silicate, at Location #7. The dust concentration was 22*8 mppcf, which is somewhat below the TLV of 30 mppcf for inert particulates. The 1971 TLV documentation, of which copies of pages 285 and 286 are enclosed, indicates most zirconium salts to be of very low toxicity, and the metal to be only slightly toxic. The TLV of 5 &/^r is based on the metal. Improved local exhaust, in addition to the presently used respirators, could improve the working condition. 14. Solvents including isopropyl alcohol and acetone are alao used in the Holdeote aaterial. Alcohol, labeled raw material #493, was being transferred from a drum bold by a fork lift truck to a drum on a platform 'scale. Using an KSA Combustible Gas Indicator, the reading was from 1* to l.j of the Lower fiqjlosive Limit (LEL), indicating from 280 to 3^0 parts per (ppm). Since this was below the TLV of 400 pps and the operation is an intermittent one, there was no apparent hazard. The higher TLV of 1000 ppm for acetone indicates that similar handling of that solve would also not be hazardous. 15. Measurements were made on the operating platform of the pulpers at Loeatio&<$y the procedures described in sections 5& and 7 above. The asbestos fiber eotat of 0.09 f/ml indlcates.no hazard. Based on inert particulates, the dust levels of 2.1 ag/>r and C.8 mppcf do not appear hazardous. If there should be a significant proportion of respirable free silica, this conclusion would be modifies''in the case of the gravimetric measurement. 16. An impinger measurement of duet at the Preciz preparation at Location #5 indicated C.J2 mppcf. One of the components was "Millwood Certified Silica". The reading waa less than the TLV of 2.7 mppcf for 100JC respirable silica, if this extreme case had occurred. The operators used respirators. There was no apparent hazard. 17. Double-cone blenders at Location #1 were inspected. Sodaah, which is Bodlna carbonate, was being charged. This is not considered a toxic material, and it does not appear in the TLV list. It was said FOSECO 2037 UMirtlHtDlliaiiifitt that dost only appears doring rotation of a blender la the umnurl case of an improperly sealed lid. There did not appear to be any haxard. 18* The Threabold Lladt Values refer to airborne concentrations of substances and represent conditions under which it is believed that nearly all workers aay be repeatedly exposed day after day without adverse effect* Because of wide variation in individual susceptibility, however, expooure of as occasional individual st or even below the threshold lisdt aay not prevent discomfort, aggravation of a pre-existing condition, or occupational illness. 19* This Investigation was Bade in accordance with IC-5, Specific Safety Bequirewts of the Industrial Commission of Ohio Relating to All Workshops ad Factories. 20. It is suggested: A. Provision of exhaust systems for the pulpers at Locations #2 and #3 could improve working conditions. i {' B. Closer proxiarlty of an exhaust Inlet to the flowing material at machines at Location #9 would improve working conditions. C.. Improved local exhaust for the charging of dry material st the Location f7 MoIdcote operation would improve working conditions. Respectfully submitted. Robert V. Hursh, P.E. Industrial Hygiene Engineer end.: TLV list, 1970 Plant layout Bulletin 2H-05-S, Silicosis pp. 285-6, 1971 TLV Documentation & 8O# o u 3 X ^g4 m % 33 3 S' *9> 3 0 2 gH /\ cU. m> ^wWtSyyiiew; - /r-| FOSECO 2040