Health Hazard Evaluations (HHEs)

(1999) Handi-Shop, Inc., Mexico, Missouri. (Click to open report)
The National Institute for Occupational Safety and Health (NIOSH) received a confidential request for a health hazard evaluation (HHE) at Handi-Shop, Inc. in Mexico, Missouri. the HHE requester was concerned that health risks may have been associated with dust exposures of workers who packaged 'NVX, STPP, and forta fiber' and noted 'there may be other work areas that should be checked also.' Workers' health problems, reportedly included allergies, rashes, sinus problems, and sneezing. The reques... (Click to show more) The National Institute for Occupational Safety and Health (NIOSH) received a confidential request for a health hazard evaluation (HHE) at Handi-Shop, Inc. in Mexico, Missouri. the HHE requester was concerned that health risks may have been associated with dust exposures of workers who packaged 'NVX, STPP, and forta fiber' and noted 'there may be other work areas that should be checked also.' Workers' health problems, reportedly included allergies, rashes, sinus problems, and sneezing. The requester also reported that 'several workers throughout the years have had doctors' orders to stop working in the dust. (Click to show less)
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(1999) Puerto Rico Aqueduct and Sewer Authority, Sergio Cuevas Bustamante Filtration Plant, Frujillo Alto, Puerto Rico. (Click to open report)
On May 6, 1998, the National Institute for Occupational Safety and Health (NIOSH) received a confidential employee request for a Health Hazard Evaluation (HHE) at the Sergio Cuevas Bustamante Filtration Plant of the Puerto Rico Aqueduct and Sewer Authority. The requesters expressed concern regarding respiratory problems and dermatitis possibly associated with exposures to hydrated lime [calcium hydroxide, Ca(OH)2], chlorine gas [Cl2], and two coagulants [GC 850 (basic aluminum chloride solution)... (Click to show more) On May 6, 1998, the National Institute for Occupational Safety and Health (NIOSH) received a confidential employee request for a Health Hazard Evaluation (HHE) at the Sergio Cuevas Bustamante Filtration Plant of the Puerto Rico Aqueduct and Sewer Authority. The requesters expressed concern regarding respiratory problems and dermatitis possibly associated with exposures to hydrated lime [calcium hydroxide, Ca(OH)2], chlorine gas [Cl2], and two coagulants [GC 850 (basic aluminum chloride solution) and PRP 4440 (polydimethydiallylammonium chloride)]. A site visit was conducted at this potable water filtration plant on June 29-30, 1998. Of the 25 people employed at the filtration plant, 19 (76%) worked the morning shift (6 a.m. to 2 p.m.), when most of the activities at the filtration plant were performed. On the day of the site visit, 17 employees were present and all were interviewed. Two of the interviewed workers reported that they were diagnosed by physicians as having asthma, which had developed since working at this plant. Both workers reported noticeable improvements of this health condition during vacations, sick leave, or lay-offs. Five of the workers (including the two asthmatics) reported at least two respiratory symptoms in the ten days preceding the interview. These symptoms included difficulty breathing, phlegm production, chest tightness, wheezing, and shortness of breath. All symptomatic workers reported that they believed their symptoms were related to long-term exposure to hydrated lime and chlorine gas. Other reported health problems included sinusitis, itchy eyes, skin rash, and dermatitis. Area air sampling for hydrated lime, chlorine, and particulates was conducted at locations and times of anticipated elevated exposures. Personal breathing zone (PBZ) air sampling for hydrated lime also was performed; however, the method used to analyze the hydrated lime failed. A count of particles in air during hydrated lime loading operations, a procedure reported by workers to often result in elevated dust levels, revealed only moderate losses of hydrated lime during loading when compared to the period after loading. No detectable levels of chlorine were measured in the area where chlorine cylinders were stored or in the room where chlorine was added to the water supply. The two coagulants of concern were confined to an area where little human exposure should occur, so monitoring was not conducted. Management and employees reported that there had been problems associated with the handling of hydrated lime in the past. A crack, still visible but repaired by the time of the NIOSH site visit, had developed in the side of a silo which contained about 130,000 pounds of hydrated lime, allowing hydrated lime to be released into the workplace. The conveyor feeding hydrated lime into the water supply was designed to have barriers around it but they had been removed and hydrated lime was observed on surfaces throughout the room. Workers reported that hydrated lime periodically escaped into the environment from the top of the silo during loading, despite a filtration system to prevent its escape. The connection between the supply truck and the pipes carrying the hydrated lime to the top of the silo was difficult to seal properly and reportedly hydrated lime was spilled. On the day preceding the NIOSH site visit, a worker received a dose of hydrated lime in the face during a maintenance task at the silo. Several other safety concerns were identified at the plant, including absence of appropriate guarding of roof openings and lack of a complete confined space entry program, which indicate that more rigorous administrative controls should be implemented. Este informe también está disponible en español: <a href="https://www.cdc.gov/niosh/hhe/reports/pdfs/1998-0217-2772.pdf"target="_blank">https://www.cdc.gov/niosh/hhe/reports/pdfs/1998-0217-2772.pdf</a>. (Click to show less)
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(1999) San Francisco Recreation and Parks Department, San Francisco, CA. (Click to open report)
In August 1996, the National Institute for Occupational Safety and Health (NIOSH) received a management request for a health hazard evaluation (HHE) from the San Francisco Recreation and Parks Department, San Francisco, California to evaluate the Parks Department's composting operation. Their request indicated that one of the three employees assigned to the composting site had experienced respiratory problems, nausea, shortness of breath, and muscle soreness. In addition, NIOSH was also asked to... (Click to show more) In August 1996, the National Institute for Occupational Safety and Health (NIOSH) received a management request for a health hazard evaluation (HHE) from the San Francisco Recreation and Parks Department, San Francisco, California to evaluate the Parks Department's composting operation. Their request indicated that one of the three employees assigned to the composting site had experienced respiratory problems, nausea, shortness of breath, and muscle soreness. In addition, NIOSH was also asked to evaluate the effectiveness of the enclosed cabs on the heavy equipment used at the compost site. On September 4, 1996, two NIOSH Industrial Hygienists conducted a site visit to the composting site and conducted limited air samples during simulated turning operations. The San Francisco Recreation and Parks Department operates a small composting operation which is located adjacent to the San Francisco Zoo. The material which is composted at this site consists of leaf, and green waste which is mixed with manure from the zoo. The green waste is collected at the city's parks and is trucked to the composting site. The zoo manure (zoo-doo) from herbivores is collected and also trucked to the site for mixing with green waste. During the surveys conducted at these composting sites, work area air samples were collected for total dusts and bioaerosols. Samples were collected during simulated operations at the compost site. Total sampling times for the samples collected were approximately two hours, and therefore, do not reflect an eight-hour time weighted concentration. Air samples were collected at locations upwind and downwind of the site, and inside and outside of the cabs of the chipper and front-end loader. Total bacteria concentrations measured inside and outside the chipper cab were 9250 and 6.06 x106 colony forming units per cubic meter of air (CFU/m3), respectively. Fungi concentrations were 9.7 x 103 CFU/m3 inside the cab and 6.8x 105 CFU/m3 outside the cab. The total dust concentration inside the cab of the loader was 0.68 milligram per cubic meter of air (mg/m3) compared to 6.69 mg/m3 outside the cab. Bacteria concentrations inside and outside the loader cab were 2.6 x 104 and 3.5 x 106 CFU/m3, respectively. Fungi concentration were lower inside the loader cab as compared to outside the cab, but not as pronounced as that seen for total dust and bacteria. Fungal concentrations inside and outside were 3.2 x 104 CFU/m3 and 4.6 x 104 CFU/m3, respectively. The results from this health hazard evaluation have shown that the enclosed machinery cabs can reduce exposures. However, these controls will be ineffective if the cab windows or doors are opened during operation. Acceptable levels of airborne microorganisms have not been established. Lack of standardized exposure assessment techniques, inability to quantitate non-viable organisms, and inter-individual variability in response have confounded efforts to set such standards. To reduce this potential hazard it is important to reduce worker exposures using either engineering controls or a combination of engineering controls and respiratory protection. The results from this health hazard evaluation indicate that enclosed machinery cabs on the equipment at the San Francisco Recreation and Parks Department sites reduce exposures to airborne fungi and bacteria. Microorganisms play such an important role in composting. Acceptable levels of airborne microorganisms have not been established. Lack of standardized exposure assessment techniques, inability to measure non-viable organisms, and inter-individual variability in response have confounded efforts to set such standards. To reduce this potential hazard it is important to minimize worker exposures using either engineering controls or a combination of engineering controls and respiratory protection. (Click to show less)
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(1999) U.S. Silica Company, Mill Creek Plant, Mill Creek, Oklahoma. (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 Mill Creek plant, in Mill Creek, Oklahoma. 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 pro... (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 Mill Creek plant, in Mill Creek, Oklahoma. 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 August 10-12, 1993, a medical evaluation of current workers was conducted. Former workers were tested on August 13-14, 1993. The medical evaluation included a questionnaire, spirometry, and a single view posterior-anterior (PA) 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. Twenty-nine (57%) of 51 current workers and 20 (33%) of 61 former workers who met the study criterion participated in the NIOSH medical evaluation. Of these 49, five (10%) had a chest x-ray consistent with silicosis. The highest median ILO profusion category was 22. One of the five had a chest x-ray consistent with progressive massive fibrosis (PMF), with "B" size large opacities as classified by all three readers. Four (9%) of the 46 participants who performed spirometry had abnormal patterns; three exhibited an obstructive lung pattern and one exhibited a combined restrictive and obstructive pattern. An abnormal spirometry pattern was present in one of the five participants with a positive chest x-ray. U.S. Silica's medical monitoring includes all of the screening tests recommended by the National Industrial Sand Association (VISA) 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 I/0 or greater and 5-10% of those chest x-rays classified as 0/1 based on a single reading. Of the company records we reviewed, company chest x-rays initially classified as negative (0/0 and 0/1) were not routinely sent for additional readings. Since 1990, the company reportedly sent chest x-rays initially classified 1/0 or greater by a single reader for additional classifications. Five (10%) of the 49 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 workers with 10 or less years of tenure; 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 will 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 regardless of examinations (TB) and modification of the baseline and routine examinations to include skin testing for tuberculosis (TB). (Click to show less)
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(1998) Active Industries, Inc., Clifton Park, New York. (Click to open report)
In May 1997, the National Institute for Occupational Safety and Health (NIOSH) received a health hazard evaluation (HHE) request from an employee of Active Industries, Clifton Park, New York. The HHE request stated that employees in the Specialized Machine Operations (SMO) area were experiencing sore throats, rashes, eye irritation, and upper respiratory congestion. The request indicated that the source of the health problems was mica, fiberglass, and Kevlar (trademark) dust, released during the... (Click to show more) In May 1997, the National Institute for Occupational Safety and Health (NIOSH) received a health hazard evaluation (HHE) request from an employee of Active Industries, Clifton Park, New York. The HHE request stated that employees in the Specialized Machine Operations (SMO) area were experiencing sore throats, rashes, eye irritation, and upper respiratory congestion. The request indicated that the source of the health problems was mica, fiberglass, and Kevlar (trademark) dust, released during the manufacture of electrical insulation products. On November 11 - 12 1997, a NIOSH investigator conducted a site visit which included an opening conference, records review, walk-through inspection, informal discussions with employees, and air sampling. (Click to show less)
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