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HHE Search Results
477 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
(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 unionidentified 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 assig... (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 unionidentified 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:
• 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.
• 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.
• 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.
• 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) An employee representative from a state-operated 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. Our evaluation consisted of speaking with employees about work processes, daily work tasks, and work-related concerns; observing work processes and wor... (Click to show more)An employee representative from a state-operated 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. Our evaluation consisted of speaking with employees about work processes, daily work tasks, and work-related concerns; observing work processes and workplace conditions; visual inspection of each building's ventilation system(s); collecting direct reading measurements for hydrogen sulfide, volatile organic compounds, carbon monoxide, carbon dioxide, temperature, and relative humidity; and reviewing written safety plans and other documents. Employees were exposed to untreated and partially treated wastewater. These exposures lead to increased risk of infection from waterborne pathogens. Employees were at risk for exposure to powdered lime. All measurements for gases were well below the most restrictive occupational exposure levels. A newly installed heating, ventilation, and air-conditioning system in the laboratory could control temperature and humidity, but could not provide outdoor air to, or exhaust air from the laboratory. We recommended ways to (1) reduce exposure to untreated sewage and chemicals, (2) address ventilation deficiencies in process buildings, (3) reduce the potential for slips, trips, and falls, and (4) 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) 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. The main facility was a large... (Click to show more)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. 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.
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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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(2022) Whole-body vibration analysis of golf course maintenance tasks. (Click to open report) The Health Hazard Evaluation Program received a request from golf course management concerning maintenance employees' exposure to whole-body vibration. Employees reported pain or discomfort in their lower back, shoulders, neck, and knees, which they thought was related to excessive whole-body vibration while doing certain work tasks. We visited the golf course to learn more about health concerns and to measure whole-body vibration exposures. During our site visit, we observed work processes, wor... (Click to show more)The Health Hazard Evaluation Program received a request from golf course management concerning maintenance employees' exposure to whole-body vibration. Employees reported pain or discomfort in their lower back, shoulders, neck, and knees, which they thought was related to excessive whole-body vibration while doing certain work tasks. We visited the golf course to learn more about health concerns and to measure whole-body vibration exposures. During our site visit, we observed work processes, work practices, and workplace conditions; measured golf course maintenance employees' exposures to whole-body vibration; and held confidential interviews with employees working during our visit. We found that most job tasks we evaluated were above the whole-body vibration dose value (VDV) action level. This could lead to employees potentially experiencing health risks. Employees reported pain or discomfort in their lower back, shoulders, neck, and knees. They also indicated that original equipment seats had been replaced with other manufacturers' seats when they wore out. This could contribute to pain and discomfort. We recommended reducing the amount of time spent on equipment, taking paths that are known to cause less vibration, providing proper replacement seats on equipment, reducing or eliminating rough and uneven areas of the cart paths through maintenance or replacement, establishing a schedule that rotates employees between job tasks, and encouraging employees to report health concerns they think are work-related to their supervisors.
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(2021) Exposure to lead during residential water line replacement activities. (Click to open report) The Health Hazard Evaluation (HHE) Program received a request from the employer of a city water department concerning lead exposure among crews replacing lead water lines servicing residential homes. This occurred after two employees received blood tests indicating elevated lead levels. In response to these findings, the employer implemented some measures to minimize lead exposures among employees and submitted an HHE request. In response to this request, we conducted confidential medical interv... (Click to show more)The Health Hazard Evaluation (HHE) Program received a request from the employer of a city water department concerning lead exposure among crews replacing lead water lines servicing residential homes. This occurred after two employees received blood tests indicating elevated lead levels. In response to these findings, the employer implemented some measures to minimize lead exposures among employees and submitted an HHE request. In response to this request, we conducted confidential medical interviews; collected personal air samples for lead; conducted colorimetric wipe sampling for lead on the hands of employees; collected wipe samples inside the surfaces of work gloves, work trucks, and areas at the main pump station; and determined whether lead particulate was expelled from the old lead pipe during a removal process. All air samples were below the occupational exposure limit for lead; however, we found lead on various surfaces and on the hands of some employees. Specific job titles such as crew leader and maintenance worker appear to have a higher potential for exposure via all routes than other job titles. We detected lead on the hands of employees who handled the lead pipe during removal activities, and lead on the inside of some work gloves after the job was completed. The task of using compressed air to blow a string through the lead piping produced a large amount of lead aerosol being ejected from the pipe. We observed incorrect respirator usage and some cases where nitrile gloves were not worn underneath work gloves when handling lead pipe. The company had a written lead monitoring and control program, a hazard communication program, and a job-hazard analysis for tasks associated with lead line replacement. While the employer had implemented multiple measures to minimize lead exposures to employees, there appears to be opportunities for potential lead exposure among employees during residential water line replacement activities. We recommended improving (1) lead surveillance, training, and work practices; (2) personal protective equipment use and training; (3) procedures for employees to keep their hands clean and free of lead during different tasks; and (4) cleaning procedures to reduce lead exposure.
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