Health Hazard Evaluations (HHEs)

(2015) Health hazard evaluation report: evaluation of 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. (Click to show less)
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(2014) Health hazard evaluation report: evaluation of 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. (Click to show less)
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(2010) Crystalline silica and isocyanate exposures during parking garage repair, Aduddell Restoration and Waterproofing, Inc., Arlington, Virginia. (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. (Click to show less)
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(2009) Employees' chemical exposures while blending and repackaging glass beads for road markings, Weissker Manufacturing, Palestine, Texas. (Click to open report)
On October 16, 2007, NIOSH received a confidential employee request for an HHE at Weissker Manufacturing (Weissker) in Palestine, Texas. Employees were concerned about exposures to lead, arsenic, formaldehyde, and dust while handling reflective glass beads. Health problems listed on the request and attributed to the dust from the glass beads included glassy eyes, sore throat, body aches, and flu-like symptoms. Weissker imported the glass beads in Super Sack containers (2200-pound capacity fabric... (Click to show more) On October 16, 2007, NIOSH received a confidential employee request for an HHE at Weissker Manufacturing (Weissker) in Palestine, Texas. Employees were concerned about exposures to lead, arsenic, formaldehyde, and dust while handling reflective glass beads. Health problems listed on the request and attributed to the dust from the glass beads included glassy eyes, sore throat, body aches, and flu-like symptoms. Weissker imported the glass beads in Super Sack containers (2200-pound capacity fabric bags) from Russia and China and repackaged the beads for resale. Both the Chinese and Russian glass beads had a silane coating. Employees complained about a fish-like odor emitted from the Chinese beads when they were wet. The odor may have come from the amines in the glass beads' coating. Weissker is no longer purchasing beads from China due to employees' health concerns. At the time of this evaluation six employees at Weissker worked one 8-hour shift. During our site visit on January 22-24, 2008, we observed the blending and repackaging process, reviewed the MSDSs for the glass beads, and interviewed employees. We also collected PBZ air samples for respirable dust, crystalline silica, elements (including arsenic and lead), and formaldehyde and GA air samples for total dust, formaldehyde, and elements. We analyzed bulk samples of glass beads for elements, VOCs, and size. We took wipe samples from employees' hands and work surfaces and had them analyzed for elements. Our review of the OSHA 300 Logs of Work-Related Injuries and Illnesses revealed that an employee was injured in June 2007, when his arm was trapped between a metal bin and a Super Sack while he was emptying it. All air sampling results were below applicable OELs. No VOCs were detected in the bulk samples of glass beads. Elements were either not detected or were detected at very low concentrations. Particle size analysis of the glass beads revealed that they were too large to be deposited in the respiratory tract or the lungs. We measured very low levels of elements on employees' hands, on work surfaces, and on the lunchroom table. We conducted confidential medical interviews with five employees; some reported eye and throat irritation. We recommend that employees wear safety glasses or goggles to prevent glass beads from getting in their eyes and that they wash their hands before eating or touching their face. We also recommend that employees not place their arms underneath the Super Sack containers when they are being emptied to prevent hand and arm injuries. (Click to show less)
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(2008) Exposures at a pottery shop, FUNKe Fired Arts (formerly known as Annie's Mud Pie Shop), Cincinnati, Ohio. (Click to open report)
On February 2, 2007, NIOSH received a management request for an HHE at FUNKe Fired Arts, previously known as Annie's Mud Pie Shop, in Cincinnati, Ohio. Although no health symptoms were reported, management was concerned about the potential for employees' long-term exposure to a variety of substances while performing duties at the pottery shop. Exposures of concern included silica from the clay mixing process, elements from mixing dry materials used in the glazes, and VOCs and gases during kiln f... (Click to show more) On February 2, 2007, NIOSH received a management request for an HHE at FUNKe Fired Arts, previously known as Annie's Mud Pie Shop, in Cincinnati, Ohio. Although no health symptoms were reported, management was concerned about the potential for employees' long-term exposure to a variety of substances while performing duties at the pottery shop. Exposures of concern included silica from the clay mixing process, elements from mixing dry materials used in the glazes, and VOCs and gases during kiln firing. Because management requires the use of respirators during clay and glaze mixing, they also requested information on proper respirator use and maintenance. On March 21, 2007, NIOSH investigators held an opening conference and toured the facility to review work processes. On April 11, 12, and May 24, 2007, NIOSH investigators collected eight 8-hour PBZ samples and six area air samples for respirable particulates and silica. Six separate PBZ samples were taken while employees performed specific dust-generating tasks. Wipe sampling for elements was conducted throughout the facility. An ergonomic evaluation of the work processes was performed. During the firing of the kilns, area air samples were taken for elements, NO2, SO2, CO, CO2, and VOCs. CO readings were also taken during forklift activities. None of the PBZ or area air samples exceeded the OSHA PELs or NIOSH RELs for any of the compounds measured, although one employee's exposure for silica was at the NIOSH REL of 0.05 mg/m3. Tasks that created the highest concentrations of respirable silica and particulates included moving bags of raw materials to and from storage and mixing clay. Short-term concentrations of silica were high, reaching 2.0 mg/m3 over 96 minutes of sampling. This exceeded ACGIH's excursion limit of 5 times the TWA TLV. VOCs, NO2, and SO2 concentrations were not detected above the MDC during the kiln-firing process. Although PBZ samples of CO were not taken during the use of the forklift, real-time area CO measurements taken at breathing zone level in the storage room peaked at 204 ppm, exceeding the NIOSH ceiling limit of 200 ppm. Due to the silica content of the clay and the potential for silica exposures to exceed OELs, we recommend using engineering controls to reduce employee exposures. This includes installing LEV in areas where high dust-generating activities take place and improving general building ventilation to allow adequate intake of outdoor air, mixing of indoor air, and dilution of potential airborne contaminants. Engineering controls are the preferred method over respirator use to reduce exposures to workplace contaminants. However, respirators should be used, and a formal respiratory protection program should be implemented until exposures can be reduced below the NIOSH REL and ACGIH excursion limit for silica. We also recommend establishing a health and safety training program for employees on appropriate equipment use and hazards. We further recommend that employees and students practice good hygiene in the workplace. Regular preventive maintenance for the forklift should be performed, eventually transitioning to a low or no emission forklift, and loading dock doors should be kept open while using the forklift to prevent the build-up of CO. (Click to show less)
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