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HHE Search Results
283 HHE reports were found based on your search terms. Reports are listed in order of year published with the most recently published reports listed first.
Year Published and Title
(2004) U.S. Department of Interior, Denver, CO. (Click to open report) In June 2003, the U.S. Department of Interior (DOI) asked NIOSH to evaluate exposure to airborne crystalline silica among rock drilling workers at Rocky Mountain National Park (RMNP) in north-central Colorado. Although employees had not reported any symptoms related to rock drilling, DOI management wanted documentation of worker exposure along with recommendations on the use of respiratory protection during the use of two types of portable gas-powered rock drills. The park employs 45 trail worke... (Click to show more)In June 2003, the U.S. Department of Interior (DOI) asked NIOSH to evaluate exposure to airborne crystalline silica among rock drilling workers at Rocky Mountain National Park (RMNP) in north-central Colorado. Although employees had not reported any symptoms related to rock drilling, DOI management wanted documentation of worker exposure along with recommendations on the use of respiratory protection during the use of two types of portable gas-powered rock drills. The park employs 45 trail workers to build new hiking trails and to maintain 360 miles of existing trails. Holes are drilled into large rocks so they can be split and used as steps for steep sections of trail. Crews of five or six workers per project use either a 75-pound drill or a 30-pound drill for splitting rocks. The larger drill forces compressed air through the drill shank as a means of keeping the drill hole free of dust. Water can not be used as a dust suppression method because it causes the drill bit to bind in the rock. The smaller drill does not have an air-flushing mechanism and water may be applied to the drill holes. The large drill can drill holes about four times faster than the small drill. Workers wear powered air-purifying respirators when using the large rock drill, since few other control options are available in remote areas. Exposure to airborne total dust, respirable dust, respirable crystalline silica (quartz and crystobalite), and carbon monoxide (CO) was evaluated for five workers during three days of sampling with maximum wind conditions of three miles per hour. Two bulk samples of rock dust contained 15% and 23% quartz. No crystobalite was found in any of the air or bulk samples. When workers used the large drill, maximum 8-hour time-weighted average (TWA) air concentrations were as follows: airborne total dust, 4.8 milligrams per cubic meter (mg/m3 ); respirable dust, 0.63 mg/m3 ; and respirable quartz, 130 micrograms per cubic meter (microg/m3 ). These results indicate that overexposure to quartz occurs if workers use the large drill without respiratory protection. All other measured contaminants were below recommended evaluation criteria. Using the small drill, 8-hour TWA exposure to total dust ranged up to 0.18 mg/m3 , respirable dust ranged up to 0.12 mg/m3 , and exposure to respirable quartz was non-detectable (< 30 microg/m3 ) during both wet and dry drilling. Low exposure to CO (up to 9 parts per million, 8-hour TWA) was found during the use of both drills. Overexposure to crystalline silica occurs when the large air-flushing, gas-powered rock drill is used on quartz-containing rock. Recommendations are provided to minimize exposure through personal hygiene, training, respiratory protection, and medical monitoring.
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(2003) The Concrete Revolution, Denver, Colorado. (Click to open report) The National Institute for Occupational Safety and Health (NIOSH) received a management request from The Concrete Revolution in Denver, Colorado, to evaluate potential occupational exposure hazards in the manufacture of custom concrete counter tops. Five site visits were made to the plant between April and October 2002. Exposure assessments were conducted for noise, respirable crystalline silica, respirable dust (or particulates not otherwise regulated, respirable fraction), and asbestos fibers.... (Click to show more)The National Institute for Occupational Safety and Health (NIOSH) received a management request from The Concrete Revolution in Denver, Colorado, to evaluate potential occupational exposure hazards in the manufacture of custom concrete counter tops. Five site visits were made to the plant between April and October 2002. Exposure assessments were conducted for noise, respirable crystalline silica, respirable dust (or particulates not otherwise regulated, respirable fraction), and asbestos fibers. Full shift exposures to noise were less than the NIOSH recommended exposure level of 85 decibels on the A-weighted scale. Personal breathing zone (PBZ) exposures to respirable crystalline silica (as quartz and cristobalite) were below the limit of detection (LOD) for quartz in one sample and at trace concentrations [between the LOD and the limit of quantitation (LOQ)] for five other samples. Cristobalite was never detected above the LOD nor were airborne asbestos fibers. Certain elements (metals) were detected in samples of settled dusts from drying rooms 1 and 2 but were in very low concentrations. Quartz was also detected in settled dust samples in concentrations of 2.0 to 3.3%. Three area and six PBZ air samples collected for respirable dust ranged in concentration from 1.8 to 10 milligrams per cubic meter of air (mg/m3). One of these samples exceeded the OSHA Permissible Exposure Limit for respirable dust of 5 mg/m3. At the time of the NIOSH survey, management and employees at the Concrete revolution were refining work practices and considering modifications to exhaust ventilation in the drying rooms to reduce particulate exposures. Work practice, housekeeping, and ventilation recommendations are provided on pages 6-7 of this report. Occupational exposure to noise, respirable crystalline silica, asbestos and metals were all below established occupational health criteria at the time of this survey. One of nine samples for respirable dust exceeded the Occupational Safety and Health Administration (OSHA) criterion of 5 milligrams per cubic meter of air as an 8-hour time-weighted average. Recommendations are provided to modify work practices and consider ventilation changes to better control dusts while patching and finishing custom concrete counter tops.
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(2002) Mueller Company, Chattanooga, Tennessee. (Click to open report) In May 1998, the National Institute for Occupational Safety and Health (NIOSH) received a confidential request for a health hazard evaluation (HHE) at the Mueller Company facility in Chattanooga, Tennessee. The HHE requesters expressed concern over exposures to formaldehyde, phenol, xylene, isocyanates, toluene, naphthalene, carbon monoxide, trimethyl benzene, cumene, lead, and silica in the Pepset, No- Bake, shell core, green sand, and iron pouring areas; silica and iron dust in the cleaning r... (Click to show more)In May 1998, the National Institute for Occupational Safety and Health (NIOSH) received a confidential request for a health hazard evaluation (HHE) at the Mueller Company facility in Chattanooga, Tennessee. The HHE requesters expressed concern over exposures to formaldehyde, phenol, xylene, isocyanates, toluene, naphthalene, carbon monoxide, trimethyl benzene, cumene, lead, and silica in the Pepset, No- Bake, shell core, green sand, and iron pouring areas; silica and iron dust in the cleaning room, shell core, green sand, and machining areas; oil mist from hydraulic tanks; and asbestos from the concrete plant floors. The HHE request listed respiratory symptoms and possibly increased cancer rates as health concerns. On March 31-April 1, 1999, NIOSH investigators conducted a walk-through survey, reviewed material safety data sheets and environmental sampling data, and interviewed 22 employees about the work environment and possible work-related health effects. Employer records were examined to determine the number of cancer cases among employees. On August 8-9, 2000, environmental monitoring was conducted for phenol, volatile organic compounds, Stoddard solvent, formaldehyde, toluene, cumene, ammonia, trimethyl benzene isomers, 4,4'-diphenylmethane diisocyanate (MDI), and hexamethylenetetramine (HMTA). Formaldehyde was detected at low levels in some air samples. MDI and HMTA were detected at low concentrations. Phenol, Stoddard solvent, toluene, cumene, ammonia, and trimethyl benzene isomers were detected at levels below current occupational exposure limits. Smoke released from the shell core ovens was found to move through the employees' breathing zones before being exhausted through the canopy hood. Twenty-one (4.4% of the 475 production workers) were interviewed. Among those interviewed, most employees who had prolonged exposure to emissions from the Pepset and No-Bake coremaking/molding operations reported transient respiratory irritation. The workers who worked in these areas on a regular basis generally did not report persistent respiratory illnesses that they associated with their workplace exposures. Review of the medical records of six employees who reported work-related respiratory illnesses found that some workers had worsening of pre-existing chronic respiratory conditions, although the cause of this was not determined. Information concerning cancer diagnosed among Mueller Co. employees did not reveal an unusual number or pattern of cancers; however, it is not possible to determine the cause of the cancers that developed among the employees. All of the substances sampled in the employees' personal breathing zones had concentrations below the occupational exposure limits. The 16 identified cancer cases were of 10 different types, and there was not enough information available to determine if the cancers resulted from workplace exposures. Among the small number of employees interviewed, most who had long term exposures to emissions in the Pepset and No-Bake coremaking/molding areas reported temporary respiratory irritation. Recommendations are provided for additional monitoring for MDI, formaldehyde, and phenol, use of gloves, reporting of health symptoms to medical personnel, and local exhaust ventilation in the shell core area.
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(2001) CSX Transportation, Inc., Nashville, Tennessee. (Click to open report) In June 1992, the Dixie Federation of the Brotherhood of Maintenance of Way Employees (BMWE) requested a National Institute for Occupational Safety and Health (NIOSH) health hazard evaluation (HHE) of railroad track maintenance operations conducted by CSX Transportation, Incorporated (CSXT). The request concerned respiratory hazards to maintenance of way (MOW) employees from dusts generated while these operations are performed "in and around Radnor Yard in Nashville, Tennessee and at most tracka... (Click to show more)In June 1992, the Dixie Federation of the Brotherhood of Maintenance of Way Employees (BMWE) requested a National Institute for Occupational Safety and Health (NIOSH) health hazard evaluation (HHE) of railroad track maintenance operations conducted by CSX Transportation, Incorporated (CSXT). The request concerned respiratory hazards to maintenance of way (MOW) employees from dusts generated while these operations are performed "in and around Radnor Yard in Nashville, Tennessee and at most trackage in Tennessee as well as other southern states." Subsequent to the request, the Dixie Federation merged with other federations and assumed the name of the Allied Eastern Federation of BMWE. On November 9, 1992, NIOSH representatives met with company and union representatives for an initial meeting and brief site visit near Radnor Yard. NIOSH then conducted environmental air sampling at eight sites during track maintenance activities between August 1993 and April 1997. Twenty-two area samples and 185 personal samples were collected for respirable dust and respirable crystalline silica. Area and personal respirable dust 10-hour time-weighted average (TWA) concentrations ranged from "not detected" to 1.04 mg/m3 and "not detected" to 2.05 mg/m3 , respectively. The range of 10-hour TWA respirable crystalline silica (as quartz) concentrations for the area samples was "not detected" to 0.30 mg/m3 and was "not detected" to 0.43 mg/m3 for the personal samples. Cristobalite, another form of crystalline silica, was not detected on any of the samples. Eighteen of the personal sample concentrations exceeded the Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (PEL) for respirable dust, and 28 exceeded the NIOSH Recommended Exposure Limit (REL) for respirable quartz; these samples were obtained on ballast regulator, broom, and tamper operators as well as track repairmen engaged in ballast dumping. In an effort to reduce worker exposure, the company was modifying operator cabs on equipment. The cabs were being rebuilt with air-conditioning and pressurization systems, and seals were being provided around doors, windows, and levers. Real-time dust measurements showed the effectiveness of these modifications to one such cab. Manual control of ballast car hopper doors was being replaced with radio remote control. NIOSH recommendations include substitution with ballast that contains less crystalline silica, wetting of the ballast to prevent dust, and maintenance of the operator cabs. NIOSH investigators determined that a health hazard existed for railroad track maintenance workers from occupational exposure to crystalline silica. The presence of this risk was indicated by personal measurements of airborne respirable crystalline silica that exceeded occupational exposure guidelines. The hazard was greatest for workers who operated ballast regulating, broom, and tamping machines and for track repairman who dumped ballast. Reduction of worker exposure to airborne dust is recommended to protect the health of the workers engaged in these activities.
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(2001) Foeste Masonry, Cape Girardeau, Missouri. (Click to open report) Foeste masonry recently received an OSHA citation for overexposure of workers to crystalline silica during the dry cutting of brick. Foeste subsequently purchased several brick/block cutoff saws equipped with water dust suppression. Until Foeste could show that exposures were adequately controlled, Foeste was required by OSHA to enroll the operators in a respiratory protection program (fit testing and use of half mask, cartridge respirators). On April 3, 2000, Foeste Masonry requested a Health H... (Click to show more)Foeste masonry recently received an OSHA citation for overexposure of workers to crystalline silica during the dry cutting of brick. Foeste subsequently purchased several brick/block cutoff saws equipped with water dust suppression. Until Foeste could show that exposures were adequately controlled, Foeste was required by OSHA to enroll the operators in a respiratory protection program (fit testing and use of half mask, cartridge respirators). On April 3, 2000, Foeste Masonry requested a Health Hazard Evaluation (HHE) to assess the effectiveness of wet dust suppression during the cutting of brick and block. On May 8, 2000, NIOSH investigators met with Foeste representatives to discuss sampling procedures for collecting airborne dust samples. Environmental measurements of airborne particulate were obtained on May 9 -10,2000. NIOSH investigators determined that dry cutting can lead to intense exposures to silica dust. Such exposures are likely to be very hazardous to workers operating the saws and working in their vicinity. NIOSH recommends that wet cutting be used when ever possible. The sampling undertaken in this study indicates that wet cutting, undertaken using the manufacturer's guidelines, generally leads to exposures to silica dust below the OSHA PEL. It is recommended that saw operators continue to wear at least a NIOSH-approved, disposable respirator, especially when wet cutting for two hours or more. If dry cutting brick or block is necessitated by the building design a Powered Air Purifying Respirator (PAPR) should be worn and the cutting time should be limited. Routine evaluation of dust exposures is desirable to ensure that the workers are adequately protected, especially for brick or block of high silica content.
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(2001) Lehigh Portland Cement Company, Union Bridge, Maryland. (Click to open report) On May 30, 2000, the National Institute for Occupational Safety and Health (NIOSH) received a health hazard evaluation (HHE) request from the Paper, Allied Industrial, Chemical, and Energy Workers Union Local 2-0031 regarding fly ash exposures during the cement manufacturing process at the Lehigh Portland Cement Company in Union Bridge, Maryland. The union was concerned about possible exposures to crystalline silica as a constituent of the fly ash (approximately 1-6%) used in the cement manufac... (Click to show more)On May 30, 2000, the National Institute for Occupational Safety and Health (NIOSH) received a health hazard evaluation (HHE) request from the Paper, Allied Industrial, Chemical, and Energy Workers Union Local 2-0031 regarding fly ash exposures during the cement manufacturing process at the Lehigh Portland Cement Company in Union Bridge, Maryland. The union was concerned about possible exposures to crystalline silica as a constituent of the fly ash (approximately 1-6%) used in the cement manufacturing process. On July 24-25, 2000, NIOSH investigators conducted a site visit at the Lehigh Portland Cement Company. Area and personal breathing zone (PBZ) air samples were collected for total dust, respirable dust, and crystalline silica. Bulk samples of the fly ash and raw feed were also collected and analyzed for crystalline silica content and elements (e.g., chromium, copper, nickel, lead, magnesium, manganese, titanium, zinc, etc.). A return site visit was conducted on December 13, 2000, to collect PBZ air samples for elements. PBZ air samples collected for respirable dust, quartz (crystalline silica), cristobalite, and elements did not indicate any exposures exceeding applicable exposure criteria. Three area samples collected at different times in the raw mill separator area indicated total dust concentrations of 149 milligrams of dust per cubic meter of air (mg/m3), 14 mg/m3, and 20 mg/m3. (The settled dust [on equipment, stairs, floors, etc.] in the raw mill area, and leaks in the process equipment may affect dust sample concentrations collected at different times during the day). Three out of seven workers sampled during the initial site visit had total dust time-weighted average (TWA) exposures above the American Conference of Governmental Industrial Hygienists' (ACGIH) Threshold Limit Value (TLV) and Mine Safety and Health Administration (MSHA) permissible exposure limit (PEL) of 10 mg/m3. Two of these workers were performing work tasks in the mill room and had TWA exposures that also exceeded the Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (PEL) for total dust (15 mg/m3). PBZ air samples collected on a worker repairing a leak in the process equipment (located within the raw mill building) indicated an extremely high total dust TWA concentration (3800 mg/m3). This sample was not representative of the worker's breathing zone exposure (dust was blowing directly on the sampling cassette at a high velocity while he was repairing the leak). However, because of the high concentration in this sample, it is possible that the worker's true exposure to total dust concentrations was well over applicable exposure criteria. All area and PBZ air samples for quartz (crystalline silica) were below applicable exposure criteria. However, PBZ air samples indicated that total dust TWA exposures were in excess of applicable exposure criteria. Recommendations to control total dust exposures include shutting off process equipment when performing maintenance activities to repair leaks; fixing leaks in process equipment to reduce dust generating sources; using engineering and administrative controls when feasible; using respirators when other controls are not feasible; using vacuums (with P95 filters) instead of pressurized air to clean off work clothing; and re-sampling after any process changes to evaluate worker exposures under new conditions.
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(2001) Special Metals Corporation, Princeton Powder Division, Princeton, Kentucky. (Click to open report) The National Institute for Occupational Safety and Health (NIOSH) conducted a health hazard evaluation (HHE) at Special Metals Corporation, Princeton Powder Division, Princeton, Kentucky. NIOSH conducted this HHE at the request of employees at that facility who were concerned about the possible formation of hexavalent chromium (Cr[VI]) in the specialty alloy production operations, and of the potential health hazards from exposures to this and other materials associated with those operations. Hea... (Click to show more)The National Institute for Occupational Safety and Health (NIOSH) conducted a health hazard evaluation (HHE) at Special Metals Corporation, Princeton Powder Division, Princeton, Kentucky. NIOSH conducted this HHE at the request of employees at that facility who were concerned about the possible formation of hexavalent chromium (Cr[VI]) in the specialty alloy production operations, and of the potential health hazards from exposures to this and other materials associated with those operations. Health effects mentioned in the request included nose bleeds, sinusitis, gastric disturbance, and fatigue. In response to this request, NIOSH investigators conducted an initial environmental and medical investigation at the site on July 23 and 24, 1997. NIOSH investigators collected 5 personal breathing-zone (PBZ) and 4 area air samples for Cr(VI), 7 PBZ and 4 area air samples for heavy metals, and 6 residual process bulk-material samples for Cr(VI). Two areas of the facility were also evaluated for noise levels. Based upon the initial findings, the NIOSH investigators determined that a follow-up visit was necessary to better characterize workers' exposures to several of the metals used at the facility, by conducting biological monitoring and additional environmental monitoring. The follow-up visit was conducted on September 17-18, 1998. During this visit, NIOSH investigators collected a total of 40 PBZ and 8 area air samples for Cr(VI), 38 PBZ and 7 area air samples for heavy metals, 4 bulk-material samples for Cr(VI), 2 PBZ air samples for respirable crystalline silica, 1 area "bulk-air" sample for crystalline silica, and 2 bulk-material samples for crystalline silica. In general, the highest PBZ air sample concentrations of nickel, cobalt, total chromium, and niobium were found in the furnace bay, laboratory, and inert screening areas. During the initial survey, 1 air sample (collected in the breathing zone of the laboratory assistant) exceeded the Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (PEL) for nickel (1000 micrograms per cubic meter [µg/m 3 ]) and cobalt (100 µg/m 3 ). Five PBZ air samples exceeded the NIOSH Recommended Exposure Limit (REL) for nickel (15 µg/m 3 ) and 1 PBZ air sample exceeded the REL for cobalt (50 µg/m 3 ). Two PBZ air samples exceeded the American Conference of Governmental Industrial Hygienists (ACGIH) Threshold Limit Values (TLV) for cobalt (20 µg/m 3 ). One PBZ air sample exceeded the NIOSH REL and the ACGIH TLV for total chromium (500 µg/m 3 ). Bulk sample analysis revealed that Cr(VI) is present in the facility, however all PBZ air sample concentrations for Cr(VI) were below relevant evaluation criteria. During the follow-up survey, 2 air samples (collected in the breathing zone of the laboratory assistant and furnace operator's helper) exceeded the OSHA PEL for nickel and cobalt. Twenty-two PBZ air samples exceeded the NIOSH REL for nickel and four PBZ air samples exceeded the REL for cobalt. Seven PBZ air samples exceeded the ACGIH TLV for cobalt. All results for total chromium were below relevant evaluation criteria. Bulk sample analysis confirmed the initial survey results that Cr(VI) is present in the facility. However, all Cr(VI) PBZ air samples collected were below relevant evaluation criteria. All samples collected for crystalline silica resulted in nondetectable concentrations. Sample results in many cases represent potential exposures, rather than actual inhalation exposures, due to employees wearing respirators. During the follow-up evaluation, all chromium and cobalt levels in urine were well below their respective biological exposure indices. There is no biological exposure index for nickel in the United States. Urine nickel levels, however, suggested that all 48 participating employees may have been exposed to nickel at work. We found a potential health hazard from exposure to nickel and cobalt at this facility. Air samples showed potential employee exposures to nickel and cobalt exceeding relevant evaluation criteria. Bulk and air samples indicated the presence of Cr(VI) in various production areas of the facility, however all personal breathing zone air samples collected for Cr(VI) were below relevant evaluation criteria. Urine samples showed evidence of workplace exposure to nickel in all employees, and suggested that low levels of workplace exposure to chromium may be occurring in a small number of workers, but offered no convincing evidence of workplace exposure to cobalt. Use of respirators (by many of the potentially highest-exposed workers) reduced actual inhalation exposures, as well as absorbed doses. Suggestions to improve the health and safety of employees in this facility, through the use of administrative controls, personal protective equipment (PPE) and particularly through the use of engineering control measures to reduce or eliminate reliance on PPE, are presented in the Recommendations section of this report.
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(2000) AFG Industries, Bridgeport, WV. (Click to open report) In July 1997, the National Institute for Occupational Safety and Health (NIOSH) received a request for a health hazard evaluation and technical assistance (HHE) from the United Steel Workers of America (USWA) to investigate possible respiratory problems at AFG Industries in Bridgeport, West Virginia. AFG Industries produces sheet glass from raw materials. The respiratory health concerns cited in the request included breathing problems and irritation including nose bleeds; and exposure concerns i... (Click to show more)In July 1997, the National Institute for Occupational Safety and Health (NIOSH) received a request for a health hazard evaluation and technical assistance (HHE) from the United Steel Workers of America (USWA) to investigate possible respiratory problems at AFG Industries in Bridgeport, West Virginia. AFG Industries produces sheet glass from raw materials. The respiratory health concerns cited in the request included breathing problems and irritation including nose bleeds; and exposure concerns included adipic acid, crystalline silica, asbestos, sulfur dioxide (SO2), and nuisance dusts. A walk-through survey was conducted on September 23, 1997. Two industrial hygiene surveys were conducted on May 18 and June 10, 1998. During these surveys, samples were collected for respirable dust and respirable crystalline silica, adipic acid, and SO2 Medical records were reviewed from 10 workers who complained of work-related respiratory illness. A self-administered questionnaire was mailed to all employees during August and September of 1998. Participants were asked about upper and lower respiratory symptoms, skin and eye symptoms, personal health history, work history, work activities, and tobacco use. Four personal and two area samples were collected for respirable dust and respirable crystalline silica; all samples were collected from the silo tower area (the hot end of the plant). The respirable dust samples ranged from 0.31 mg/m^3 to 4.86 mg/m^3. The personal crystalline silica concentrations ranged from 0.09 mg/m^3 to 0.35 mg/m^3. The workers assigned to the silo tower used respiratory protection by company policy. The disposable respirators used by workers had an assigned protection factor (APF) of 10 and, when used properly, would reduce exposures ten-fold. Thus, these crystalline silica exposures, if attenuated by proper respirator use, would be below the existing Occupational Safety and Health Administration (OSHA) Permissible Exposure Limits (PEL), the NIOSH Recommended Exposure Limit (REL), and The American Conference of Governmental Industrial Hygienists (ACGIH), Threshold Limit Exposure Values (TLVs). However, the results from crystalline silica sampling demonstrate the potential for overexposure among workers in the silo tower area if respirators are not used or used improperly. Fifteen total dust samples were collected for adipic acid in air including 14 personal samples and 1 area sample. Adipic acid was used in the cold end of the plant. The total dust concentrations from this area ranged from 0.25 mg/m^3 to a high of 1.68 mg/m^3. The total adipic acid concentrations ranged from 0.01 mg/m^3 to a high of 0.89 mg/m^3; the mean adipic acid concentration from the total dust samples was 0.10 mg/m^3 with a standard deviation (SD) of 0.22 mg/m^3. The adipic acid content of the airborne total dust samples ranged from 3% to 53% by weight; the mean percent by weight adipic acid concentration in airborne total dust was 13.8% with a SD of 12%. These concentrations were below the existing ACGIH TLV. Sulfur dioxide was not detected in any of the seven short term area samples taken. Plant management reported that asbestos materials had been removed form the plant and no friable asbestos insulation was observed during this survey. Of the 312 questionnaires mailed, 144 (46%) were returned; 138 had complete information and were used for the analysis. Results of self-reported respiratory symptoms showed cough in the morning by 42%, phlegm in the morning by 47%, chest tightness by 53%, and wheeze by 52%. Symptoms were also stratified by smoking status and job category; results indicated that lower respiratory symptoms increased among former smokers from the hot end. Overall, work-related health problems were reported in 47% of the workers. These conditions included upper respiratory symptoms by 60%, mucosal irritation by 26%, musculoskeletal by 18%, and hearing loss by 14%. Overall nasal bleeding was reported by 25% (35 of 138) of the workers. Stratification by job category indicated that 30% of cold end workers reported nasal bleeding, as did 23% of the hot end workers, 22% of the warehouse workers, and 7% of maintenance workers. The frequency of nose bleeding was reported 1 to 4 times a year in 74% of the cases. Overall skin irritation was reported in 43% (59 of 138) of the workers. Symptoms by job category indicated that 47% of cold end workers reported skin irritation, as did 69% of the hot end workers, 17% of the warehouse workers, and 36% of maintenance workers. Overall eye irritation was reported by 71% (98 of 138) of the workers. Symptoms by job category indicated that 75% of worker in the cold end reported eye irritation, 69% of hot end workers, 57% of the warehouse workers, and from 79% of maintenance workers. These findings suggest a high prevalance of mucosal irritation symptoms among plant workers in both cold end and hot end areas. Thirteen cases of alleged pneumoconiosis were identified in the OSHA 200 logs; this prompted a review of the medical records. Ten medical records were obtained. Of these, the average age was 42 years. The tenure in the glass industry was 21 years. Radiographic evaluations conducted by certified B Readers from a medical group contracted by the company as well as NIOSH's B Reader physician did not document any finding related with occupational pneumoconiosis. A review of AFG's OSHA 200 log from 1996 included 63 cases of musculoskeletal injuries, seven cases of alleged pneumoconiosis, three cases of hearing loss, and two eye related injuries. During the first nine months of 1997, 41 cases of musculoskeletal injuries, one case of eye injury, and one case of SO2 inhalation were reported.
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(2000) Haverhill High School, Haverhill, Massachusetts. (Click to open report) On January 27, 1999, the National Institute for Occupational Safety and Health (NIOSH) received a confidential request from staff at Haverhill High School in Haverhill, Massachusetts, for an evaluation of exposures to crystalline silica and other compounds in ceramics. The request indicated that employees were concerned about developing emphysema, silicosis, and/or asthma due to exposure to ceramics materials. In addition, the request indicated that staff were concerned about exposures to vari... (Click to show more)On January 27, 1999, the National Institute for Occupational Safety and Health (NIOSH) received a confidential request from staff at Haverhill High School in Haverhill, Massachusetts, for an evaluation of exposures to crystalline silica and other compounds in ceramics. The request indicated that employees were concerned about developing emphysema, silicosis, and/or asthma due to exposure to ceramics materials. In addition, the request indicated that staff were concerned about exposures to various materials used in five art rooms, and the woodworking shop. On April 27, 1999, an initial site visit was conducted which included an opening conference, informal discussions with teachers, and a walk-through inspection of the art rooms and woodworking shop. During the walk-through, activities were identified in ceramics and woodworking classrooms which could result in exposure to crystalline silica, metals, and wood dust. On May 4, 1999, a second site visit was conducted where environmental monitoring was conducted for airborne crystalline silica in the ceramics classroom, and wood dust in the woodworking shop. Surface wipe sampling for metals was conducted in ceramics. Measured concentrations of respirable crystalline silica were below the NIOSH Recommended Exposure Limit (REL) during the monitoring period. Neither of the respirable area samples revealed detectable levels of crystalline silica. Total crystalline silica (quartz) concentrations of 0.070 milligrams per cubic meter (mg/m3) and 0.075 mg/m3 were quantified in bulk air samples collected at the wedging table and at the center of the classroom, respectively. A bulk sample of settled dust, collected from a shelf adjacent to the door leading to the corridor, contained 25% quartz. Cristobalite was not detected in any of the samples. Gravimetric analysis of air samples indicates that concentrations of all airborne particulates were below occupational exposure limits for particulates not otherwise regulated (PNOR). Surface wipe sampling for metals found the highest concentrations of metals in the storage closet where glazes are prepared from powdered materials. Local exhaust ventilation (LEV) is not provided at the wedging table or in the glaze preparation area. The highest concentration of wood dust (3.4 mg/m3 during a 50-minute period) was measured in the personal breathing zone (PBZ) sample collected on the woodworking instructor. A similar concentration (3.2 mg/m3 during a 78-minute period) was measured in the vicinity of two students who were using hand-held orbit sanders at a "homemade" downdraft table. The presence of crystalline silica in a settled dust sample indicates a need for LEV and appropriate housekeeping practices in the ceramics classroom. Air samples collected in the woodworking shop indicate that current LEV is not providing effective control of wood dust. Recommendations include substituting premixed glazes, installation of effective LEV systems in ceramics and woodworking classrooms, improved housekeeping practices in ceramics, and implementation of an effective Chemical Hazard Communication Program.
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(2000) U.S. Silica - Columbia, Cayce - W. Columbia, SC. (Click to open report) In July 1991, the National Institute for Occupational Safety and Health (NIOSH) received a request for technical assistance from the Mine Safety and Health Administration (MSHA) to estimate the prevalence of silicosis among active and retired miners at U.S. Silica Company's Columbia plant, in Cayce-W. Columbia, South Carolina. Current and former workers with one year or greater cumulative tenure since 1970 in the grinding area of the mill or in areas downstream (by material processing) of the g... (Click to show more)In July 1991, the National Institute for Occupational Safety and Health (NIOSH) received a request for technical assistance from the Mine Safety and Health Administration (MSHA) to estimate the prevalence of silicosis among active and retired miners at U.S. Silica Company's Columbia plant, in Cayce-W. Columbia, South Carolina. Current and former workers with one year or greater cumulative tenure since 1970 in the grinding area of the mill or in areas downstream (by material processing) of the grinding process represented the population of primary interest. On February 24-25, 1994, a medical evaluation of current workers was conducted. Former workers were tested on February 26-27, 1994. The medical evaluation included a questionnaire, spirometry, and a single view posterior-anterior(P A) chest x-ray. Chest x-rays were independently classified according to the 1980 International Labour Office (ILO) system by three NIOSH-certified B readers who were unaware of the participant's age, occupation, occupational exposure, smoking history, or any identifying information. For the purposes of this evaluation, silicosis was defined on the basis of a chest x-ray with median small opacity profusion classification of category 1/0 or greater. Thirty-five (90%) of 39 current workers and 11 (65%) of 17 former workers who met the study criterion participated in the NIOSH medical evaluation. Of these 46, four (9%) had a chest x-ray consistent with silicosis. The highest median ILO profusion category was 2/2. Two of the four had a chest x-ray consistent with progressive massive fibrosis (PMF). Twelve (27%) of the 45 participants who performed spirometry had abnormal patterns; all 12 exhibited an obstructive lung pattern. Abnormal spirometry patterns were present in all four of the participants with a positive chest x-ray. U.S. Silica's medical monitoring included all of the screening tests recommended by the National Industrial Sand Association (NISA) as well as those recommended by NIOSH for workers exposed to ground silica. NISA's current guidelines also, recommend multiple readings of all, chest x-rays with a small opacity profusion, classification of 1/0 or greater and 5-10% of those chest x-rays classified as 0//l, based on a single reading. Since 1990, the company reportedly sent chest x-rays initially classified 1/0 or greater by a single reader for additional classifications. Of the company records we reviewed, chest x-rays initially classified as negative (0/0 and 0/1) were not routinely sent for additional readings, and the practice of sending chest x-rays classified 1/0 or greater for additional readings was not consistent. Four (9%) of the 46 survey participants who met the study criterion were found to have chest x-ray findings consistent with silicosis. These results are consistent with patterns of crystalline silica dust exposure at this facility. There were no cases of silicosis among current or former workers with 15 or less years of employment; however, because of the long latency usually associated with chronic silicosis, this finding is not sufficient to conclude that current crystalline silica dust exposure levels are without adverse effect. The company medical monitoring practice of obtaining additional B reader classifications of those chest x-rays initially classified 1/0 or greater may produce an estimated prevalence no higher than and possibly lower than that obtained with a single reading, and those workers with a positive chest x-ray whose chest x-rays are initially read as 0/0 or 0/1 will not be identified. Recommendations are presented in this report and include obtaining at least two readings of all chest x-rays regardless of the initial small opacity profusion classification, increasing the frequency of medical monitoring examinations and modification of the baseline and routine examinations to include skin testing for tuberculosis (TB).
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