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HHE Search Results
285 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
(2018) A thermal drying process at a wastewater treatment plant. (Click to open report) The Health Hazard Evaluation Program received a request from employees at a wastewater treatment plant who were concerned about exposures to thermally dried sewage sludge. In particular, employees were concerned about odors, upper airway irritation, and dust exposures from the newly-installed thermal dryer. We reviewed the process flow and thermal dryer operations, collected air samples and bulk samples for endotoxins and silica, conducted confidential health interviews with employees, and revie... (Click to show more)The Health Hazard Evaluation Program received a request from employees at a wastewater treatment plant who were concerned about exposures to thermally dried sewage sludge. In particular, employees were concerned about odors, upper airway irritation, and dust exposures from the newly-installed thermal dryer. We reviewed the process flow and thermal dryer operations, collected air samples and bulk samples for endotoxins and silica, conducted confidential health interviews with employees, and reviewed records. Exposures to endotoxins and silica were low. Dust and odors were detected throughout the facility. We surveyed employees about work-related symptoms related to working with a new thermal sewer sludge dryer. The most common health symptoms reported by employees were eye irritation, coughing, nasal congestion, and headaches. Strong odors were reported by employees during the treatment process. We observed potential fire hazards in the thermal dryer area because dryer conditions led to overheating of sludge and the presence of combustible dust. We observed that respirators were not always used, maintained, or stored correctly. In addition, correct use of other personal protective equipment such as gloves and safety glasses was inconsistent. We recommended the company work with the thermal dryer manufacturer to ensure that the equipment is working according to design and all safety mechanisms are operational; ensure that respirators are properly worn, maintained, and stored, and employees are trained on how to use them; and improve the personal protective equipment use and compliance.
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(2018) Lead and isocyanate exposure in a maintenance facility with small arms repair and vehicle painting shops. (Click to open report) The Health Hazard Evaluation Program received a request from a small arms repair and vehicle maintenance facility. A manager was concerned about airborne lead and take-home lead exposures in the small arms repair shop as well as employees' exposures to hazardous painting products, including isocyanates in the military vehicle painting shop. To evaluate employee exposures to lead we collected personal air, hand, and surface wipe samples and we evaluated blood lead levels. For isocyanates, we coll... (Click to show more)The Health Hazard Evaluation Program received a request from a small arms repair and vehicle maintenance facility. A manager was concerned about airborne lead and take-home lead exposures in the small arms repair shop as well as employees' exposures to hazardous painting products, including isocyanates in the military vehicle painting shop. To evaluate employee exposures to lead we collected personal air, hand, and surface wipe samples and we evaluated blood lead levels. For isocyanates, we collected personal air samples for hexamethylene diisocyanate and tested the employees' blood to look for isocyanate exposure and sensitization. We evaluated the ventilations systems in both areas. Although we detected no lead in the personal air samples, we did find lead on employees' hands after they had washed them, and one elevated blood lead level. We found hexamethylene diisocyanate in the air in the spray paint shop, and one employee had a blood test, which showed antibodies to a specific isocyanate (isophorone diisocyanate) in the paint, confirming recent exposure. We observed multiple opportunities for dermal exposure to paints that contained isocyanates. The firing line of the range had turbulent airflow, creating irregular mixing of air. The spray paint booth had missing and damaged filters and did not adequately remove paint overspray from the breathing zone of employees. We recommended the employer start an isocyanate medical surveillance program, use a lead removal product for hand washing and cleaning work surfaces, and have employees wear nitrile gloves while repairing firearms. We also recommended the employer provide eye and face protection and appropriately-sized protective suits for spray painting vehicles. Ventilation recommendations included reducing firing line turbulence and replacing the spray paint booth with a downdraft ventilation paint booth.
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(2017) Exposure to crystalline silica, welding fume, and isocyanates during water heater manufacturing. (Click to open report) The Health Hazard Evaluation Program received a union request about employees' exposures to silica during tank finishing operations, welding fume during tank fabrication, and methylene diphenyl diisocyanate (MDI) during tank insulation using a spray foam application. We measured exposure to airborne crystalline silica, welding fume, and MDI, held medical interviews, administered medical questionnaires, and collected blood for biomarkers of isocyanate exposure and sensitization. We found overexpo... (Click to show more)The Health Hazard Evaluation Program received a union request about employees' exposures to silica during tank finishing operations, welding fume during tank fabrication, and methylene diphenyl diisocyanate (MDI) during tank insulation using a spray foam application. We measured exposure to airborne crystalline silica, welding fume, and MDI, held medical interviews, administered medical questionnaires, and collected blood for biomarkers of isocyanate exposure and sensitization. We found overexposure to crystalline silica during brushing, tank and flue spraying, and mill room operations. Methylene diphenyl diisocyanate and welding emissions were below occupational exposure limits. Employees reported symptoms consistent with work-related asthma. Two employees had MDI-specific IgE, consistent with MDI asthma, in their blood. Five employees had MDI-specific IgG in their blood, indicating recent exposure to MDI despite the use of engineering controls and personal protective equipment. Some employees in foam booths cut slits in their Tyvek suit to aid in cooling, creating a potential for skin exposure to MDI. Some ventilation controls were either not working or were ineffective in containing airborne contaminants. Improvements in ventilation system design, use, and maintenance are needed. The employer should also begin a medical surveillance program for employees exposed to MDI and silica and provide training on the hazards of working with both.
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(2016) Crystalline silica exposure during fabrication of natural and engineered stone countertops. (Click to open report) The Texas Department of State Health Services asked the Health Hazard Evaluation (HHE) Program for help. They asked us to evaluate silica exposure in a manufacturing plant. The plant makes natural and engineered stone countertops. We measured employees' exposures to crystalline silica. We evaluated ventilation systems and personal protective equipment use. Employees used wet methods to help control dust. We found respirable crystalline silica in the air. Concentrations ranged from nondetectable ... (Click to show more)The Texas Department of State Health Services asked the Health Hazard Evaluation (HHE) Program for help. They asked us to evaluate silica exposure in a manufacturing plant. The plant makes natural and engineered stone countertops. We measured employees' exposures to crystalline silica. We evaluated ventilation systems and personal protective equipment use. Employees used wet methods to help control dust. We found respirable crystalline silica in the air. Concentrations ranged from nondetectable to 140 micrograms per cubic meter (ug/m3). Respirable dust concentrations ranged from nondetectable to 380 ug/m3. The percentage of quartz in these samples ranged from less than 1% to 52%. We found overexposures to crystalline silica despite the use of wet methods. None of the work processes used local exhaust ventilation. We saw some employees incorrectly using respirators, safety glasses, and ear plugs. The company did not have an employee medical surveillance program for silica. HHE Program investigators recommended using a combination of local exhaust ventilation and wet methods to control dust.
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(2016) Respiratory concerns at a coal and copper slag processing company. (Click to open report) In September 2012, the National Institute for Occupational Safety and Health received a management request for a health hazard evaluation at a coal slag processing facility in Illinois. Management submitted the health hazard evaluation request as part of a settlement with the Occupational Safety and Health Administration. The Occupational Safety and Health Administration inspected one of the company's coal processing facilities in 2010 and identified multiple health and safety violations and a s... (Click to show more)In September 2012, the National Institute for Occupational Safety and Health received a management request for a health hazard evaluation at a coal slag processing facility in Illinois. Management submitted the health hazard evaluation request as part of a settlement with the Occupational Safety and Health Administration. The Occupational Safety and Health Administration inspected one of the company's coal processing facilities in 2010 and identified multiple health and safety violations and a suspected cluster of pneumoconiosis in four former workers. As part of the settlement, the company requested a health hazard evaluation to determine if cases of pneumoconiosis were present in current workers and assess dust hazards. We evaluated airborne exposures during coal and copper slag processing. We took air samples for the analysis of dust, silica, and metals to investigate respiratory concerns. Overall, copper slag processing produced higher levels of dust, silica, and metals compared to coal slag processing, but both processes posed health risks. We recommend employee exposure monitoring and a formal respiratory protection program.
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(2015) Aerogel insulation particulate at a union training facility. (Click to open report) The Health Hazard Evaluation Program received a request from an insulators union concerned with exposure to particulate released when handling aerogel insulation. Union members reported nosebleeds, upper respiratory tract irritation, and skin dryness. Two union employees provide training for over 200 apprentices and 800 journeymen per year at a training facility. The number of trainees has recently increased. We took personal air samples for components of aerogel insulation (amorphous and crysta... (Click to show more)The Health Hazard Evaluation Program received a request from an insulators union concerned with exposure to particulate released when handling aerogel insulation. Union members reported nosebleeds, upper respiratory tract irritation, and skin dryness. Two union employees provide training for over 200 apprentices and 800 journeymen per year at a training facility. The number of trainees has recently increased. We took personal air samples for components of aerogel insulation (amorphous and crystalline silica, aluminum, iron, and titanium) while an instructor applied aerogel insulation. We looked at the shape, size, and size distribution of the airborne particulate released from handling aerogel insulation. Over two days, we observed the work practices of an instructor who handled aerogel insulation during training. We asked students, journeymen, and an instructor about exposure to aerogel insulation, use of personal protective equipment, medical history, symptoms, and personal hygiene practices while training at this facility and at their job site(s). Airborne exposures for amorphous silica approached occupational exposure limits, while crystalline silica, aluminum, iron, and titanium were below the most protective occupational exposure limits. Most of the particulate released during aerogel handling was respirable and can be inhaled deep into the lungs. Many participants who handled aerogel insulation reported upper respiratory tract irritation, or very dry or chapped skin. We recommended the instructors (1) educate staff and students about potential upper respiratory tract irritation and drying effects from prolonged exposure to aerogel insulation, (2) encourage staff and students to report work-related health problems to their supervisor, (3) explore alternative cleansers that are more effective than soap and water but will not contribute to skin drying, and (4) provide staff and students with personal protective equipment described in the manufacturer's safety data sheets.
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(2015) Erionite and silica exposure during forestry activities. (Click to open report) A federal government agency requested a health hazard evaluation. The agency wanted to know about the hazards from erionite exposure. In some areas of the Custer National Forest where its employees worked, the agency knew or suspected the presence of erionite. Erionite is a mineral that occurs in nature in most areas in the western United States. Erionite fibers can cause health effects like those seen with exposure to asbestos. Crystalline silica is another mineral found in many geologic format... (Click to show more)A federal government agency requested a health hazard evaluation. The agency wanted to know about the hazards from erionite exposure. In some areas of the Custer National Forest where its employees worked, the agency knew or suspected the presence of erionite. Erionite is a mineral that occurs in nature in most areas in the western United States. Erionite fibers can cause health effects like those seen with exposure to asbestos. Crystalline silica is another mineral found in many geologic formations. We took air samples and analyzed them for erionite and silica. We took rock and soil samples and analyzed them for erionite. We considered the samples positive for erionite when they met several criteria. One criterion was that the fibers were longer than 5 micrometers. Another was that the fibers had a length to width aspect ratio greater than 3:1. The final criterion was that the fibers contain silicon, aluminum, and at least one of the elements calcium, sodium, or potassium. We found erionite fibers in the air, rock, and soil samples. We did not find overexposures to respirable crystalline silica. But, some air samples taken during specific tasks contained silica.
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(2014) Erionite and silica exposure during dirt road maintenance. (Click to open report) The Health Hazard Evaluation Program received a request from a management representative at a federal government agency concerned about potential employee exposures to erionite mineral fibers when maintaining dirt roads in areas where erionite was confirmed or was suspected to be present. We visited two field offices to assess potential employee exposures to erionite and respirable crystalline silica (quartz) during road maintenance activities in October 2012 and August 2013. Erionite is a natur... (Click to show more)The Health Hazard Evaluation Program received a request from a management representative at a federal government agency concerned about potential employee exposures to erionite mineral fibers when maintaining dirt roads in areas where erionite was confirmed or was suspected to be present. We visited two field offices to assess potential employee exposures to erionite and respirable crystalline silica (quartz) during road maintenance activities in October 2012 and August 2013. Erionite is a naturally occurring mineral found in fine-grained sediments such as volcanic ash deposits that have been altered by weathering and ground water. Erionite deposits have been identified in all of the western states except Washington. We observed employees blading and grading dirt roads, replacing culverts and cattle guards, replacing aggregate on parking lots, and pulverizing and analyzing rock samples. We took air samples for mineral fibers and crystalline silica and bulk rock and soil samples to analyze for erionite. We found that employees doing road maintenance activities could be exposed to quartz above the recommended limits. Area air samples indicated a high percentage of quartz, up to 100%. Zeolite mineral fibers, a class of fibers that includes erionite, were not found in the personal air samples. None of the bulk rock samples collected in the areas surrounding where employees worked contained erionite. Because of the variable environmental and geological conditions encountered by the employees and the variability in job tasks, including tasks that aerosolize dust particles, the potential for exposure to erionite and silica dust exists. Therefore, minimizing dust exposure during dust-generating activities is prudent. To address the potential for exposure to dust that may contain erionite or crystalline silica, we recommended the employer (1) not use aggregate that contains erionite to repair roads, (2) maintain air filters in the equipment regularly, (3) wet the soil before doing road maintenance, (4) schedule dust-generating tasks on days when the soil is moist, and (5) provide employees with clothes that are solely designated for work activities. We also recommended monitoring employees' exposure to respirable crystalline silica, and training employees in proper work practices for working in areas that contain crystalline silica or erionite. We recommended employees keep the windows and doors on equipment closed, and not bring work clothing home.
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(2014) Occupational exposures at an electronic scrap recycling facility. (Click to open report) The Health Hazard Evaluation Program received a request from a health and safety manager at an electronic scrap recycling facility. The employer was concerned about workplace exposures, including lead and cadmium. Computers, monitors, hard drives, televisions, printers, light bulbs, and other e-scrap were recycled and processed at this facility. The recycling operations included cathode ray tube (CRT) processing (demanufacturing and glass breaking operations, and electronic sorting, demanufactur... (Click to show more)The Health Hazard Evaluation Program received a request from a health and safety manager at an electronic scrap recycling facility. The employer was concerned about workplace exposures, including lead and cadmium. Computers, monitors, hard drives, televisions, printers, light bulbs, and other e-scrap were recycled and processed at this facility. The recycling operations included cathode ray tube (CRT) processing (demanufacturing and glass breaking operations, and electronic sorting, demanufacturing, shredding, and bailing operations for all other electronics. We made multiple visits between 2012 and 2013 to evaluate employee exposures to workplace contaminants. We collected air samples for metals, dust, and crystalline silica; surface wipe samples for metals; and blood and urine samples for metals. We also did employee medical interviews; reviewed the facility's health and safety monitoring plans; and evaluated noise, engineering controls, and ergonomics in the work areas. We measured an overexposure to lead during shredder sorting and overexposures to cadmium on two employees during CRT buffing and grinding. We measured overexposures to noise on employees during CRT buffing and grinding, shredder sorting, forklift driving, and baling. We found metal contamination on surfaces throughout the facility; potentially contaminated air was recirculated back into the production area. We found lead on the clothing and skin of employees and on work surfaces. Blood lead levels ranged up to 13.7 micrograms per deciliter of blood. Two employees were above 10; a level of 10 or above is considered elevated. We noted the potential for taking lead and other contaminants outside of the workplace. Employees were exposed to ergonomic risk factors including extreme working postures, forceful exertions, and repetitive motions. Our recommendations to the employer included (1) following the OSHA lead and cadmium standards, (2) starting a medical monitoring program for all employees exposed to lead, (3) starting a hearing conservation program, (4) requiring respirator use in CRT buffing and grinding and shredder operations, (5) using wet methods or a vacuum with a high efficiency air filter instead of sweeping, and (6) designing work tasks and workstations to reduce bending, lifting, and other postures that do not allow employees to work efficiently and comfortably. We recommended the employees (1) provide and discuss this report with their doctor and discuss blood lead tests for their children and other family members, (2) wear required personal protective equipment, and (3) take a shower at the end of the shift and avoid wearing work clothing or shoes home.
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(2010) Crystalline silica and isocyanate exposures during parking garage repair. (Click to open report) On November 30, 2007, NIOSH received a request from managers at Aduddell Restoration and Waterproofing, Inc. for an HHE at the Ballston Mall Parking Garage in Arlington, Virginia. The managers wanted to know if the employees were adequately protected against silica and MDI during parking garage repair. Full-shift PBZ air samples for respirable particulates and silica were collected on four employees over 2 days. The amount of MDI monomer in a bulk sample of Part A and Part B was measured. We als... (Click to show more)On November 30, 2007, NIOSH received a request from managers at Aduddell Restoration and Waterproofing, Inc. for an HHE at the Ballston Mall Parking Garage in Arlington, Virginia. The managers wanted to know if the employees were adequately protected against silica and MDI during parking garage repair. Full-shift PBZ air samples for respirable particulates and silica were collected on four employees over 2 days. The amount of MDI monomer in a bulk sample of Part A and Part B was measured. We also evaluated the curing time after mixing MDI-containing Part A and the inert Part B. Employees were exposed to hazardous levels of respirable crystalline silica during jackhammering and sandblasting. Of the eight PBZ air samples for respirable dust and silica, seven reached or exceeded the silica (as quartz) ACGIH TLV of 0.025 mg/m3, and five reached or exceeded the NIOSH REL of 0.05 mg/m3. None of the samples exceeded the OSHA PEL. Approximately 52% of the bulk sample of Part A was MDI monomer. Part B contained no MDI monomer. A quantitative analysis of the reaction between Part A and Part B showed that approximately 80% of the MDI monomer reacted in the first 10 minutes. At 60 minutes, the mixture was hardened. We considered inhalation exposure to MDI unlikely because of the low vapor pressure of MDI, the relatively short curing time between the MDI-containing Part A and the inert Part B, and the method used to pour and apply the MDI-containing slurry. However, we believed there was a potential for dermal exposure to MDI that could result in sensitization, asthma, and contact dermatitis. We interviewed all 10 employees who were working during our site visit; none reported work-related health concerns. The company provided the appropriate type of respirator for crystalline silica and required employees to wear it. However, not all job tasks requiring respirators were clearly defined. Additionally, employees were neither respirator fit-tested nor did they clean or maintain their respirators properly. We recommend informing employees that MDI monomer may still exist after Parts A and B are mixed together and requiring them to wear butyl rubber gloves when mixing these compounds. We also recommend requiring employees to wear respirators during jackhammering and sandblasting. The company's respirator program should comply with the OSHA Respiratory Protection Standard. Additional recommendations included exploring possible engineering controls to reduce dust levels while jackhammering and sandblasting; complying with the OSHA Hazard Communication Standard; evaluating employees' exposure to noise during jackhammering and sandblasting activities; providing antivibration gloves to employees who use vibrating tools such as jackhammers; wearing eye protection while sandblasting, jackhammering, or mixing and applying filler material; and establishing a smoking cessation program.
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