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HHE Search Results
479 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
(2026) Cancer concerns among employees at an elementary school. (Click to open report) The National Institute for Occupational Safety and Health (NIOSH) received a Health Hazard Evaluation (HHE) request from management at an elementary school to evaluate concerns about the number of cancer cases diagnosed among school employees. During our evaluation we (1) met with management, employee representatives, union representatives, and state public health representatives regarding the concerns, (2) reviewed a list of deidentified, self-reported cancer diagnoses provided by management, (... (Click to show more)The National Institute for Occupational Safety and Health (NIOSH) received a Health Hazard Evaluation (HHE) request from management at an elementary school to evaluate concerns about the number of cancer cases diagnosed among school employees. During our evaluation we (1) met with management, employee representatives, union representatives, and state public health representatives regarding the concerns, (2) reviewed a list of deidentified, self-reported cancer diagnoses provided by management, (3) reviewed reports of previous evaluations and environmental sampling conducted from 2015-2025, and (4) reviewed documents describing pest control, groundskeeping, and custodial chemical use and reviewed associated safety data sheets (SDS). Our evaluation found no evidence of a workplace carcinogenic at levels known to cause cancer and no evidence of an unusual pattern of cancer cases among school employees. We did not identify evidence of an excess number of cancer cases among employees, an unusual distribution of cancer types reported by employees, or potential employee exposures to hazardous levels of cancer-causing substances in the workplace. Although we do not think further case finding or investigation would lead to the identification of an unusual pattern of cancer among employees at this time, we acknowledge that concerns about the occurrence of cancer among school employees can have an important effect on employee health. Therefore, we provide recommendations to assist management in continuing to evaluate concerns and ensure the workplace is safe and healthy for all employees.
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(2025) Cutoff saw operators' noise exposures at an unleaded brass foundry. (Click to open report) Request: Management from an unleaded brass foundry requested a health hazard evaluation to evaluate noise exposures and identify potential noise controls for the abrasive cutoff saws in the foundry. Management also requested an evaluation on how well employees' hearing protectors worked. Workplace: The facility consisted of a foundry, machining and manufacturing area, distribution department, and offices. The company produced lead-free valves such as backflow preventers, mixing valves, plumbing ... (Click to show more)Request: Management from an unleaded brass foundry requested a health hazard evaluation to evaluate noise exposures and identify potential noise controls for the abrasive cutoff saws in the foundry. Management also requested an evaluation on how well employees' hearing protectors worked. Workplace: The facility consisted of a foundry, machining and manufacturing area, distribution department, and offices. The company produced lead-free valves such as backflow preventers, mixing valves, plumbing valves, heating valves, pressure reducing valves, temperature and pressure relief valves, and ball valves for use in residential, commercial, and industrial applications. The workplace had 250 employees and operated two work shifts per day. Employees normally worked 10-hour shifts. Our Approach: We visited the foundry in December 2019 to evaluate noise in the cutoff area. During our visit, six saw operators worked at the abrasive cutoff saws. Most of these saw operators divided their time between the cutoff saws and other areas with lower noise levels such as the grinders, core room, or melt deck. The cutoff saw operators worked 10-hour shifts. We completed the following activities during our visit: a) Observed work processes, production practices, and conditions. b) Measured full-shift personal noise exposures on six cutoff saw operators. c) Measured task or equipment related sound levels across noise frequencies in the cutoff area of the foundry. d) Conducted hearing protector fit-testing on six cutoff saw operators. Our Key Findings: 1) Cutoff saw operators were overexposed to noise. 2) Hearing protector fit testing showed that cutoff saw operators' hearing protection did not always provide enough protection. 3) Some employees did not always wear their hearing protection properly, which reduced how well the protectors worked. Our Recommendations: Recommendation 1: Reduce hearing loss risk from on-the-job noise exposure. How? At your workplace, we recommend these specific actions: Use engineering controls at the saw blades, cutting deck, and enclosure to reduce noise exposure. Use administrative controls to reduce noise exposure. Continue to include saw operators in a hearing loss prevention program.
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(2025) Exposure to lead during work on and near lead-sheathed telecommunication cables. (Click to open report) Request: A union representing workers at a telecommunications provider requested a health hazard evaluation (HHE) to evaluate lead exposure among workers conducting repair, maintenance, and installation of telecommunications cables. Workplace: The local union represented telecommunications workers working across two states. The union identified three garages with a higher concern of possible lead exposure to focus on for the evaluation. At the beginning of a shift, workers gathered at their assi... (Click to show more)Request: A union representing workers at a telecommunications provider requested a health hazard evaluation (HHE) to evaluate lead exposure among workers conducting repair, maintenance, and installation of telecommunications cables. Workplace: The local union represented telecommunications workers working across two states. The union identified three garages with a higher concern of possible lead exposure to focus on for the evaluation. At the beginning of a shift, workers gathered at their assigned garage and received important messages and assignments for the day. Workers drove their work vehicle with equipment to the field site. Some workers did not report to a garage before arriving to the field site, driving their work vehicle to and from their homes or a central office location. Workers then conducted their assignment of repairing, maintaining, or installing telecommunications cables in crews of at least two workers. Depending on the assignment, multiple crews may work together or near one another to complete the work. The field sites vary and can be categorized based on where the telecommunication cables exist: a) Underground environments (also known as manholes): telecommunication manholes are typically located in urban environments. These manholes provide access points to telecommunication cables and equipment under streets or sidewalks. Manholes vary in size, which can affect the ability of a worker to move around in the manhole. Between manholes, telecommunication cables run through plastic or metal tubes called conduits. b) Central offices: facilities or buildings where telecommunication service providers house equipment and infrastructure necessary to manage, route, and switch communication signals. Central offices are a hub for handling local telecommunication services and have a large volume of telecommunications cables. c) Aerial environments: telecommunication cables are attached to utility poles and require workers to use a bucket truck to access and work on cables. These environments are open-air and can vary in height. d) Other locations may also exist where telecommunication cables are present and need repair. Examples include inside residences or in shallow trenches. Wires within a cable are protected from the elements by several layers of material, one of which may be a layer of lead. In lead-sheathed telecommunication cable, the lead sheath protects the insulated conductors (wires) within. Some lead-sheathed cable remains in use. Some lead-sheathed cables have been removed and replaced by plastic-sheathed and fiber-optic cables, while some have been abandoned in place. For repair work, workers cut open a lead-sheathed cable or a plastic covering to access the wires within a cable. For underground installation work, workers entered a series of manholes to prepare conduits for installation of new cable. At the end of the shift, workers cleaned up at the field site and returned either to the garage, directly back home, or to a central office. Assignments could vary in duration from several hours to several weeks, depending on the type of assignment.
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(2025) Indoor environmental quality at a state-operated wastewater treatment plant. (Click to open report) Request: An employee representative from a state wastewater treatment plant requested a health hazard evaluation concerning indoor environmental quality. Employees were concerned about ventilation issues in the buildings housing the wastewater treatment operations, specifically the laboratory building, where employees spent most of their workday. Additional concerns included potential exposures to process chemicals, bacteria and other pathogens, and mold. Workplace: Built in 1978, the wastewater... (Click to show more)Request: An employee representative from a state wastewater treatment plant requested a health hazard evaluation concerning indoor environmental quality. Employees were concerned about ventilation issues in the buildings housing the wastewater treatment operations, specifically the laboratory building, where employees spent most of their workday. Additional concerns included potential exposures to process chemicals, bacteria and other pathogens, and mold. Workplace: Built in 1978, the wastewater plant treated, processed, and disposed of sewage from the adjacent state prison. It was designed to process 310,000 gallons a day but was only processing 80,000 gallons a day during our visit. Both of the employees assigned to the facility were on-site and working during our visit. Our Approach: Upon receiving the request, we spoke with employees to better understand their concerns. We also spoke with management to better understand policies and procedures in place at the facility. We reviewed written safety plans and other documents provided to us by management. We visited the workplace in June 2024 to learn more about the workplace environment where we did the following: a) Spoke with employees about work processes, daily work tasks, and work-related concerns. b) Observed work processes and workplace conditions. c) Visually inspected each buildings ventilation system(s). d) Collected direct reading measurements for hydrogen sulfide, volatile organic compounds, carbon monoxide, carbon dioxide, temperature, and relative humidity. Our Key Findings: 1) We found deficiencies and recent improvements in building ventilation systems. 2) Employees were exposed to untreated water and partially treated water. 3) Employees were at risk for exposure to powdered lime. 4) Employees were at risk of slips, trips, and falls. Our Recommendations: Recommendation 1: Address ventilation deficiencies in process buildings. Recommendation 2: Install controls and improve work practices to reduce exposure to untreated sewage. Recommendation 3: Install controls and improve work practices to reduce exposure to chemicals. Recommendation 4: Reduce employee exposures that could lead to slips, trips, and falls. Recommendation 5: Address other health and safety issues we identified during our evaluation.
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(2025) Potential hazards during growing and manufacture of cannabis products at an indoor cultivation and retail facility. (Click to open report) Request - Management at an indoor cannabis cultivation facility requested a health hazard evaluation of potential hazards associated with the harvesting, trimming, processing, and manufacturing of products for medicinal and recreational use. They were specifically concerned about exposures to dust, ozone, cannabis compounds, and microbial contaminants such as endotoxin and fungi. Management also asked for an evaluation of work practices that could lead to increased exposures. Workplace - The mai... (Click to show more)Request - Management at an indoor cannabis cultivation facility requested a health hazard evaluation of potential hazards associated with the harvesting, trimming, processing, and manufacturing of products for medicinal and recreational use. They were specifically concerned about exposures to dust, ozone, cannabis compounds, and microbial contaminants such as endotoxin and fungi. Management also asked for an evaluation of work practices that could lead to increased exposures. Workplace - The main facility was a large single-story building with an adjacent retail area. The building contained grow rooms (greenhouses), a mother room for the original plant strains, harvesting and drying rooms, laboratory facilities for quality control and extraction, production areas, a waste processing area, and a separate loading dock. The waste processing and loading dock areas had elevated ceilings. The evaluation was designed to characterize potential exposures for employees working with cannabis plants and plant materials. We visited the facility in April and July 2019 and completed the following activities: a) Conducted confidential interviews about work and health concerns with employees who did cultivation, harvesting, trimming, and production activities. b) Observed work processes, work practices, and conditions. c) Measured employee and area exposures to endotoxins in air. d) Sampled surfaces for cannabinoids including delta-9 tetrahydrocannabinol (Δ9-THC), delta-9 tetrahydrocannabinol acid (Δ9-THCA), cannabidiol (CBD), and cannabinol (CBN). e) Identified fungi in personal and area air samples using gene sequencing. f) Measured sound levels for two machines in the production and laboratory areas of the facility. g) Measured area ozone concentrations in air. h) Measured area particulate concentrations in air during harvesting, trimming, and production activities. i) Measured area terpenes and other volatile organic compounds concentrations in air. j) Measured area carbon dioxide concentrations in air in the grow rooms. Our Key Findings: 1) Employees reported health symptoms that could be associated with potential exposures at work. 2) Employees were exposed to particulates and endotoxins in the air, cannabinoids on surfaces, and noise from equipment. 3) Employees were exposed to highly repetitive work that increased their risk of musculoskeletal disorders. Our Recommendations: Recommendation 1: Reduce exposures to particulates throughout the facility. Also provide respiratory protection for employees applying pesticides. Recommendation 2: Reduce exposures to cannabinoids in the workplace. Recommendation 3: Encourage employees with work-related health concerns to talk to their supervisor or healthcare provider about their exposures to endotoxins, cannabinoids, particulates and musculoskeletal issues. Recommendation 4: Reduce risks for musculoskeletal disorders. Recommendation 5: Reduce potential exposures to noise in the workplace.
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(2024) Exposure to lead during bullet recycling. (Click to open report) Management of a lead bullet recycling company requested a health hazard evaluation to evaluate lead exposure among employees processing lead-containing bullets. We visited the facility on two occasions and completed the following activities: observed work processes, practices, and conditions; measured employees' lead exposure in air and throughout the facility; collected wipe samples for lead on surfaces outside of the warehouse; interviewed employees to learn about work history, health and safe... (Click to show more)Management of a lead bullet recycling company requested a health hazard evaluation to evaluate lead exposure among employees processing lead-containing bullets. We visited the facility on two occasions and completed the following activities: observed work processes, practices, and conditions; measured employees' lead exposure in air and throughout the facility; collected wipe samples for lead on surfaces outside of the warehouse; interviewed employees to learn about work history, health and safety concerns, PPE use, training, and possible work-related health effects; and reviewed documents and employee BLL data. We found that most employees were overexposed to lead in air. Surface sampling showed lead was being tracked outside of production areas. Lead was also found inside employees' respirator facepieces. Employee blood lead levels were elevated. Historical records of employee blood lead levels suggest that medical removal from work or to job duties with lower exposure has been the predominant intervention in successfully reducing employee blood lead levels thus far, further indicating a need for improved controls. Recommendations included (1) improving local exhaust ventilation over the melting pots/furnaces to better enclose the melting process, (2) reducing employees' exposure to lead through improved medical surveillance, cleaning, training, and work practices, and (3) reducing exposure to molten lead splashes by installing an automatic strainer.
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(2024) First responders' biological monitoring results after Maui County Hawaii wildfires. (Click to open report) The National Institute for Occupational Safety and Health (NIOSH) received technical assistance requests from Maui County and the Hawai'i National Guard through a mission assignment from the Federal Emergency Management Agency to evaluate first responders' exposures to chemicals and inorganic elements during the 2023 Maui Wildfires. We visited Maui County and the Maui County Fire Department in September 2023 to evaluate potential chemical and inorganic elements exposures in firefighters and othe... (Click to show more)The National Institute for Occupational Safety and Health (NIOSH) received technical assistance requests from Maui County and the Hawai'i National Guard through a mission assignment from the Federal Emergency Management Agency to evaluate first responders' exposures to chemicals and inorganic elements during the 2023 Maui Wildfires. We visited Maui County and the Maui County Fire Department in September 2023 to evaluate potential chemical and inorganic elements exposures in firefighters and others who responded to the Maui wildfires. We completed the following activities during our evaluation: measured the amount of markers of exposure to a variety of substances; administered two questionnaires to collect responders' demographic, work, and potential exposure characteristics while responding to the wildfires; analyzed the exposure marker results by self-reported demographic, occupational, and exposure characteristics collected on the questionnaires; and categorized participating responders by employer and job into a variety of occupational subcategories. We found (1) that some employees had levels of inorganic elements above relevant reference values, (2) almost all Maui County and Hawai'i National Guard participants had detectable levels of per- and polyfluoroalkyl substances (PFAS), polybrominated diphenyl ethers (PBDEs), and organophosphate esters (OPEs), (3) some associations between occupation and the levels of inorganic elements and exposure markers measured in Maui County employees, and (4) we did not observe clear patterns between self-reported exposure characteristics and the exposure markers we measured in blood and urine. In the report, we made recommendations pertaining to following best practices during wildfires and during fire debris cleanup to prevent exposure to inorganic elements, PFAS, flame retardants, and other chemicals related to products of combustion.
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(2024) Mercury and noise exposure at a lightbulb recycler. (Click to open report) Management at an electronics waste and lamp recycling facility requested a health hazard evaluation concerning employees' exposure to mercury, lead, and noise. During our two visits, we observed work processes, practices, and conditions, measured employees' exposure to mercury in air and the amount of mercury in employees' urine; interviewed employees to learn about work history and practices, health and safety concerns, personal protective equipment use, training, and possible work-related heal... (Click to show more)Management at an electronics waste and lamp recycling facility requested a health hazard evaluation concerning employees' exposure to mercury, lead, and noise. During our two visits, we observed work processes, practices, and conditions, measured employees' exposure to mercury in air and the amount of mercury in employees' urine; interviewed employees to learn about work history and practices, health and safety concerns, personal protective equipment use, training, and possible work-related health effects; and measured employees' exposure to noise. Some employees had (1) airborne mercury exposures exceeding NIOSH and ACGIH occupational exposure limits, (2) elevated urine mercury levels and reported symptoms consistent with mercury exposure, and (3) noise exposures over the NIOSH recommended exposure limit. In addition to employee exposures, we measured elevated concentrations of mercury in the air throughout the facility, including in nonproduction areas. Additionally, we observed mercury-containing dust piles throughout the facility and areas where engineering and administrative controls could be used to reduce the potential for exposures. Air sampling results indicate worker exposures to mercury and noise exceeded relevant occupational exposure limits. We noted high urine mercury levels in employees who had high occupational exposure to mercury in air and found high occupational exposure to mercury even in nonproduction areas. Some employees also reported symptoms consistent with mercury exposure, suggesting exposures to mercury may have led to health effects. Some of these exposures could be preventable with improved ventilation, housekeeping practices, and health and safety programs. In addition, some workers were exposed to noise over the NIOSH recommended exposure limit. Equipment enclosures and preventative maintenance of equipment may help reduce hazardous noise exposures in these areas. Our recommendations included (1) installing local exhaust ventilation and repairing existing systems, (2) improving housekeeping procedures, (3) standardizing the use of personal protective equipment among employees who are exposed to mercury-containing dusts, (4) improving the hearing loss prevention program, (5) periodically reevaluating workplace equipment and safety and health programs, and (6) encouraging employees to report any new, persistent, or worsening health symptoms, especially those with a work-related pattern, to their healthcare providers.
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(2023) Exposures to styrene during ultraviolet cured-in-place pipe installation. (Click to open report) In October 2017, the Health Hazard Evaluation Program of the National Institute for Occupational Safety and Health (NIOSH) received a request from the management of an ultraviolet cured-in-place pipe installer regarding styrene exposures at the worksites. The request sought to determine whether exposures were controlled using current practices and identify areas for improvement. We conducted an initial visit during February 5-6, 2018, and performed preliminary sampling at one site per day. We co... (Click to show more)In October 2017, the Health Hazard Evaluation Program of the National Institute for Occupational Safety and Health (NIOSH) received a request from the management of an ultraviolet cured-in-place pipe installer regarding styrene exposures at the worksites. The request sought to determine whether exposures were controlled using current practices and identify areas for improvement. We conducted an initial visit during February 5-6, 2018, and performed preliminary sampling at one site per day. We conducted a second visit during June 6-7, 2018, and performed additional sampling at one site per day. We monitored one installation each day. Both visits consisted of collecting personal breathing zone air samples for styrene. Both visits also consisted of area sampling for total volatile organic compounds and styrene using real-time monitors. During the second visit, we collected real-time total volatile organic compound exposures by placing monitors on employees. We collected bulk samples of cured pipe for styrene emissions testing. One personal exposure during grinding a cured pipe was above the NIOSH short-term exposure limit of 100 parts per million when the manhole ventilation blower fan was not being used to provide dilution of air from outside the manhole. No personal exposures were above the NIOSH short-term exposure limit when the manhole ventilator blower fans were used. Area sampling results for total volatile organic compound and styrene emissions at the manhole face increased when cured-in-place pipe installation activities occurred in the manhole and demonstrated a reduction in measured styrene when manhole blower ventilators were used. Styrene was emitted from the uncured and cured resin. Emissions testing of the cured liner revealed emission factors that could cause styrene air concentrations to be in the parts per million range in manholes for sewers and storm water drains during cured-in-place pipe installation. For example, during grinding of the cured pipe, the surface area available for emissions increased, and the trapped styrene was released, leading to an increase in measured styrene exposures during this task. Dilution ventilation appeared to be effective at reducing personal exposures to below the NIOSH short-term exposure limit for styrene during the two cured-in-place pipe installation sampling events reported here. We recommend continued use of the manhole ventilation blower fans. We recommend additional sampling if employees report health symptoms associated with styrene exposure, such as excessive tiredness, changes in color vision, slowed reaction time, concentration problems, balance problems, feeling drunk, hearing loss, or respiratory symptoms. We also recommend additional sampling if work site conditions change in a way that could increase employee exposures to styrene such as changes to processes, materials, or work practices.
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(2023) Symptoms among above-wing uniformed airline employees. (Click to open report) The National Institute for Occupational Safety and Health (NIOSH) received multiple confidential employee requests for a health hazard evaluation at a commercial airline. Employees were concerned about health effects they associated with their new, mandatory uniforms. The requestors also reported that many employees were hesitant to formally report health and safety problems related to the uniform to airline management for fear of being removed from their work assignments. Our evaluation consist... (Click to show more)The National Institute for Occupational Safety and Health (NIOSH) received multiple confidential employee requests for a health hazard evaluation at a commercial airline. Employees were concerned about health effects they associated with their new, mandatory uniforms. The requestors also reported that many employees were hesitant to formally report health and safety problems related to the uniform to airline management for fear of being removed from their work assignments. Our evaluation consisted of speaking with airline managers and employees, reviewing documents provided by airline management, analyzing data on worker's compensation claims and accommodations requests, and reviewing scientific literature on health effects related to textiles, skin and allergy conditions, and health effects seen in flight attendants. We found that employees reported a variety of symptoms they thought were related to the new uniforms, but wearing new uniform pieces did not lead to a widespread outbreak of symptoms. Skin or allergy symptoms were the most common symptom types mentioned in workers' compensation data. Of the records we reviewed, no uniform-related workers' compensation claims or accommodation requests were approved. The most common reason for a workers' compensation claim denial was the lack of treatment and diagnosis. Uniform-related accommodation requests were commonly closed because the employee did not submit any documents for review. Airline representatives said a positive patch test for skin allergy was generally needed for a successful workers' compensation claim or uniform-related accommodation request. Although, no positive patch tests had been reported at the time of this HHE, people with skin symptoms who do not test positive might have other skin conditions. Some symptoms employees reported could be associated with the uniforms, although we faced challenges linking symptoms to uniforms. We made detailed recommendations to the airline that focused on allowing for more flexibility in the uniform wear policy and improving communication to address employee concerns.
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