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HHE Search Results
115 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) A cluster of unexplained illnesses among employees in an office building following overnight building renovation. (Click to open report) Request: A state epidemiologist requested technical assistance from the Health Hazard Evaluation Program concerning a cluster of unexplained illnesses among employees who worked in a state office building undergoing renovation. Workplace: Employees worked at an office building leased by five state agencies and several private tenants. The single-story building was about 55,000 square feet. Part of the building was undergoing renovation at the time of our evaluation. The area under renovation was... (Click to show more)Request: A state epidemiologist requested technical assistance from the Health Hazard Evaluation Program concerning a cluster of unexplained illnesses among employees who worked in a state office building undergoing renovation. Workplace: Employees worked at an office building leased by five state agencies and several private tenants. The single-story building was about 55,000 square feet. Part of the building was undergoing renovation at the time of our evaluation. The area under renovation was about 12,000 square feet. Employees included in the evaluation worked in the offices of two state agencies in the building. Thirty four employees worked in the office adjacent to the renovation space (Agency A) and two worked in another office in the building (Agency B). All employees primarily did office work. Agency A employees met with clients and helped process applications for social services benefits such as Medicaid and Supplemental Nutrition Assistance Program (SNAP). Agency B employees provided services related to driver license testing.
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(2025) Indoor dampness, mold, and ventilation at a college. (Click to open report) Request: In June 2022, the National Institute for Occupational Safety and Health (NIOSH) received a Health Hazard Evaluation request from union representatives and confidential employees regarding concerns about indoor dampness, mold, and ventilation system maintenance in multiple buildings located on a college campus. Workplace: The college campus included 14 buildings located on approximately 100 acres. Buildings were used as residence halls, dining rooms, lecture halls, laboratories, study ro... (Click to show more)Request: In June 2022, the National Institute for Occupational Safety and Health (NIOSH) received a Health Hazard Evaluation request from union representatives and confidential employees regarding concerns about indoor dampness, mold, and ventilation system maintenance in multiple buildings located on a college campus. Workplace: The college campus included 14 buildings located on approximately 100 acres. Buildings were used as residence halls, dining rooms, lecture halls, laboratories, study rooms, auditoriums, student and recreational services, library, museum, guest housing, and facilities/maintenance. The college had approximately 420 employees, and approximately 1,100 students lived and learned on the campus. Employee concerns about indoor dampness and mold had especially been noted after a new campuswide water chiller system was completed in 2018. Multiple employees reported a wide range of health concerns, many with work-related patterns that involved multiple body systems and were severe enough to necessitate approved or requested full-time virtual work. Our Approach: We visited the college on two occasions to learn more about the concerns related to indoor dampness, potential exposure to mold, and ventilation system operations and maintenance. Before our visits, we reviewed documents provided to NIOSH, including indoor air sampling reports, campus building floor plans, ventilation maps and drawings, and employee reports of indoor environmental quality and health concerns. During the first visit on August 9-11, 2022, we a) Held an opening meeting with employee representatives, union representatives, and management. b) Toured nine buildings and talked with employees, union representatives, and management. c) Assessed the interior and exterior of buildings for indications of water damage or mold growth. d) Observed building ventilation systems. e) Learned about the campus-wide water chiller system. f) Held a closing meeting with employee representatives, union representatives, and management. After the first visit, we a) Requested follow-up documents, including additional mechanical ventilation systems drawings. Management promptly provided the additional documents. b) Provided an interim report on September 27, 2022 with recommendations for improving indoor environmental quality. c) We provided a second interim report on January 4, 2023 that summarized reports of air sampling for mold in various campus buildings during 2011-2022. During the second visit March 7-9, 2023, we a) Held an opening meeting with employee representatives, union representatives, and management. b) Conducted ventilation assessments of four buildings. c) Learned from facilities management about their methods for responding to occupant health and safety concerns. d) Held a closing meeting with employee representatives, union representatives, and management. After the second visit, we reviewed field notes, mechanical drawings, and ventilation assessment information. During our visits, facilities management and union representatives were helpful in facilitating access to various areas across campus. They showed us examples of moisture issues and ongoing remediation efforts throughout different buildings and discussed with us current efforts to address mold and moisture concerns comprehensively across the entire campus. Our Key Findings: 1) Persistent high indoor humidity and concerns for proper ventilation system operation. 2) Lack of vapor barriers in crawl spaces. 3) Campus-wide mold and moisture concerns. Our Recommendations: Recommendation 1: Reduce moisture and humidity in basements and crawl spaces. Recommendation 2: Maintain ventilation systems for optimal indoor air quality. Recommendation 3: Correct sources of dampness and remediate moisture- and mold-damaged materials. Recommendation 4: Continue communication, reporting, and information dissemination for building-related issues. Recommendation 5: Consider implementing institutional and organizational changes that support long-term remediation efforts.
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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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(2024) Occupational exposures and indoor environmental quality in an underground cavern workplace. (Click to open report) An employer representative of a warehouse facility, located in a former underground limestone quarry, requested a health hazard evaluation concerning employees' exposures to carbon monoxide, wood dust and other airborne particles, noise, and radon. During our visits, we (1) observed work processes, practices, and workplace conditions, and spoke with employees; (2) measured carbon monoxide, carbon dioxide, temperature, and relative humidity, and radon; (3) collected air samples for wood dust, oth... (Click to show more)An employer representative of a warehouse facility, located in a former underground limestone quarry, requested a health hazard evaluation concerning employees' exposures to carbon monoxide, wood dust and other airborne particles, noise, and radon. During our visits, we (1) observed work processes, practices, and workplace conditions, and spoke with employees; (2) measured carbon monoxide, carbon dioxide, temperature, and relative humidity, and radon; (3) collected air samples for wood dust, other airborne particles, and noise; (4) used tracer gas to measure the air exchange rate in the workspace; (5) took sound level measurements when powered woodworking equipment and tools were used; and (6) measured illumination levels at various locations throughout the space. We found employees' noise exposures in the woodshop exceeded the NIOSH recommended exposure limit due to noise generated during the use of powered woodworking equipment. Wood dust exposures in the woodshop could exceed occupational exposure limits depending on how much time woodworking equipment was used. Carbon monoxide and radon levels were well below occupational exposure limits. The air exchange was very low as the warehouse as there was not a mechanical ventilation system to bring outdoor air into workspace. Temperature and relative humidity levels were within ASHRAE guidelines. Our measurements indicated that illumination could be improved in some areas of the workspace. We recommended including woodshop employees in a hearing loss prevention program, which includes audiometric testing, proper hearing protection use, and employee training; improving wood dust capture at the saws; increasing lighting in various areas of the workspace; and adding a portable toilet, handwashing station, emergency eyewash, and drinking water within the work area.
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(2023) Occupational exposures and indoor environmental quality in an underground cavern workplace (superseded). (Click for full summary) This document has been superseded and the new version can be found <a href="https://www.cdc.gov/niosh/hhe/reports/pdfs/2018-0181-3389.pdf"target="_blank">here</a>. An employer representative of a warehouse facility, located in a former underground limestone quarry, requested a health hazard evaluation concerning employees' exposures to carbon monoxide, wood dust and other airborne particles, noise, and radon. During our visits, we (1) observed work processes, practices, and workplace conditions,... (Click to show more)This document has been superseded and the new version can be found <a href="https://www.cdc.gov/niosh/hhe/reports/pdfs/2018-0181-3389.pdf"target="_blank">here</a>. An employer representative of a warehouse facility, located in a former underground limestone quarry, requested a health hazard evaluation concerning employees' exposures to carbon monoxide, wood dust and other airborne particles, noise, and radon. During our visits, we (1) observed work processes, practices, and workplace conditions, and spoke with employees; (2) measured carbon monoxide, carbon dioxide, temperature, and relative humidity, and radon; (3) collected air samples for wood dust, other airborne particles, and noise; (4) used tracer gas to measure the air exchange rate in the workspace; (5) took sound level measurements when powered woodworking equipment and tools were used; and (6) measured illumination levels at various locations throughout the space. We found employees' noise exposures in the woodshop exceeded the NIOSH recommended exposure limit due to noise generated during the use of powered woodworking equipment. Wood dust exposures in the woodshop could exceed occupational exposure limits depending on how much time woodworking equipment was used. Carbon monoxide and radon levels were well below occupational exposure limits. The air exchange was very low as the warehouse as there was not a mechanical ventilation system to bring outdoor air into workspace. Temperature and relative humidity levels were within ASHRAE guidelines. Our measurements indicated that illumination could be improved in some areas of the workspace. We recommended including woodshop employees in a hearing loss prevention program, which includes audiometric testing, proper hearing protection use, and employee training; improving wood dust capture at the saws; increasing lighting in various areas of the workspace; and adding a portable toilet, handwashing station, emergency eyewash, and drinking water within the work area.
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(2022) Potential hazards during harvesting and trimming cannabis at an indoor cultivation facility. (Click to open report) Management at an indoor cultivation facility requested a health hazard evaluation of potential hazards during harvesting and trimming of cannabis crops. During our two visits to the facility, we observed the work processes, personal protective equipment use, and workplace conditions of employees as they performed cultivating, harvesting, drying, and trimming tasks. We sampled for endotoxins, fungi, and particulates in air, sampled surfaces for cannabinoids, and measured sound levels. We also con... (Click to show more)Management at an indoor cultivation facility requested a health hazard evaluation of potential hazards during harvesting and trimming of cannabis crops. During our two visits to the facility, we observed the work processes, personal protective equipment use, and workplace conditions of employees as they performed cultivating, harvesting, drying, and trimming tasks. We sampled for endotoxins, fungi, and particulates in air, sampled surfaces for cannabinoids, and measured sound levels. We also conducted confidential medical interviews with employees. We found that employees were concerned about potential exposures to ozone, bright lights, and pesticides, among others. Employees reported allergic, irritant, and musculoskeletal symptoms they believed were associated with their work. Employees were exposed to endotoxins in the air during harvesting and repotting activities where soil and plant matter was disturbed. These exposures were greater than the Dutch Expert Committee on Occupational Safety occupational exposure limit. Measured sound levels were below NIOSH and OSHA exposure limits. Trimming employees had exposures to highly repetitive work that increased their risk of musculoskeletal disorders, most notably during hand trimming activities. We provided recommendations to reduce exposures to endotoxins, cannabinoids, ozone, light, and noise. Some of these recommendations included cleaning using wet methods or high efficiency particulate air (HEPA) filter vacuums, using hand tools to move and mix soil, training employees about the importance of removing gloves and washing hands before using the bathroom, eating, drinking, or smoking, adjusting the current ozone generation practices to reduce the chance of accidental ozone generation with employees present. We also recommended that they reduce the risk of musculoskeletal disorders, such as improving the workstations for trimming employees, and obtaining regular input from employees about workplace safety, health, and well-being issues.
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(2021) Indoor environmental quality and health concerns among employees of a public elementary school. (Click to open report) The NIOSH Health Hazard Evaluation Program received a confidential request from employees of a public elementary school because they were concerned that they might be experiencing a greater burden of general and reproductive medical conditions than was typical. Employees were concerned that these medical conditions were related to something in their work environment, specifically mold or other causes of poor indoor environmental quality at the school. During our visit we visually inspected every... (Click to show more)The NIOSH Health Hazard Evaluation Program received a confidential request from employees of a public elementary school because they were concerned that they might be experiencing a greater burden of general and reproductive medical conditions than was typical. Employees were concerned that these medical conditions were related to something in their work environment, specifically mold or other causes of poor indoor environmental quality at the school. During our visit we visually inspected every room in the school and their associated HVAC systems; measured temperature, relative humidity, carbon monoxide, and carbon dioxide levels in various areas; and interviewed employees about their work and their health. We observed evidence of past roof leaks but found no visible mold, or wet/damp areas inside the school. We observed a leaking hose bibb and two HVAC system condensate drains in the courtyard that did not drain into their respective drainpipes. The unit ventilators were original to the building, approaching the end of their expected service life, and some were partially or completely blocked by books, classroom supplies, or furniture. Carbon dioxide levels were well above outdoor levels and temperature or relative humidity levels exceeded guidelines in some classrooms. Some areas of the school that were not designed for prolonged occupancy were being used as classrooms. Many of the symptoms reported by employees, such as headaches and nasal irritation, are common in the general population but are also associated with inadequate ventilation. We found no evidence that other reported medical problems were occurring more frequently among school employees compared with other similar populations, or that these medical problems could be related to the school. We recommended prioritizing the renovation or replacement of classroom ventilation systems, starting an indoor environmental quality management program with a designated indoor environmental quality manager or administrator, and improving communication with employees about reported hazards and the steps being taken to address those concerns. We also recommended encouraging employees to (1) report concerns about work-related symptoms or medical issues to their supervisor or another designee, and (2) to seek evaluation and care (if needed) from a healthcare provider who is knowledgeable in occupational medicine for work-related medical concerns.
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(2020) Respiratory and other health concerns at a law enforcement office building with indoor environmental quality issues. (Click to open report) Water intrusion throughout the law enforcement building envelope resulted in hidden mold in wall cavities and under flooring. Hidden mold is consistent with employee reports of musty odors, especially after rains, and health symptoms. The county has taken action to prevent further water intrusion through the foundation, including re-grading the ground to direct water away from the exterior building. The concrete slab will need to dry out and then be tested again for moisture before installing co... (Click to show more)Water intrusion throughout the law enforcement building envelope resulted in hidden mold in wall cavities and under flooring. Hidden mold is consistent with employee reports of musty odors, especially after rains, and health symptoms. The county has taken action to prevent further water intrusion through the foundation, including re-grading the ground to direct water away from the exterior building. The concrete slab will need to dry out and then be tested again for moisture before installing compatible replacement flooring. If the concrete slab moisture cannot be controlled, other options need to be considered including using breathable floor coatings or installing a moisture vapor suppression system. Mold and moisture-damaged materials should be removed or cleaned with appropriate containment to minimize exposure for remediation workers, building occupants, and unaffected sections of the building. The bat droppings identified in a wall cavity also should be removed, and the area cleaned. Inappropriate remediation can cause further problems and symptoms in occupants. The amount of fresh air delivered to occupied spaces within the building was originally incorrect, due to the elimination of planned outdoor airflow monitoring stations during HVAC system installation. However, the outdoor airflow rates were appropriately adjusted by Holistic Test and Balance, Inc. during their ventilation testing and balance assessment on February 4, 2019. If building spaces are renovated or repurposed for different uses in the future, new testing and balancing of the impacted ventilation systems should be performed to ensure appropriate outdoor airflow to those occupied areas. Temperature in occupied spaces should be maintained from 68.5 degrees F to 75 degrees F in the winter, and from 75 degrees F to 80.5 degrees F in the summer, while indoor humidity should always be maintained to provide a maximum indoor-air dew-point temperature of 60 degrees F. Implementation of a thorough HVAC preventative maintenance program and the creation of a comprehensive, written HVAC operation and maintenance plan for the facility would further help ensure proper HVAC system operation and indoor environmental quality. Establishing a team for improved communication and reporting of environmental or health concerns can help prevent future building-related health symptoms.
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(2019) Indoor environmental quality with limited surface sampling for metals at an office building. (Click to open report) In December 2017, the National Institute for Occupational Safety and Health's Health Hazard Evaluation Program received a request from the union representing employees working in an office building. Employees were concerned about air quality throughout the building. Employee health concerns included breathing issues; eye irritation; skin lesions, and allergy attacks that they attributed to dampness and mold in the building, and particulates from the heating, ventilation, and air-conditioning sys... (Click to show more)In December 2017, the National Institute for Occupational Safety and Health's Health Hazard Evaluation Program received a request from the union representing employees working in an office building. Employees were concerned about air quality throughout the building. Employee health concerns included breathing issues; eye irritation; skin lesions, and allergy attacks that they attributed to dampness and mold in the building, and particulates from the heating, ventilation, and air-conditioning systems. Employees were concerned about particulates from the heating, ventilation, and air-conditioning system supply air vents. Specifically, employees were concerned the heating, ventilation, and air-conditioning system contained residual particulates with metals from when the building was used to manufacturer jewelry roughly 30 years ago. On June 1, 2018, we performed a walkthrough of the office building and performed wipe sampling to analyze particulates for metals found on office furniture and in areas near the heating, ventilation, and air-conditioning system supply air vents. During our walkthrough, we identified a number of potential issues related to indoor environmental quality at this office building, some of which were caused by retrofitting an industrial building into an office building. Indoor environmental quality issues included signs of a dusty environment, indoor dampness, improperly functioning heating, ventilation, and air-conditioning system, and rodents and pests. Management reported receiving notifications regularly from employees that fragrances in the workplace caused mucous membrane or respiratory symptoms. We recommend creating a health and safety committee consisting of employees who work throughout the building to engage with management on issues such as comfort (temperature and relative humidity), indoor dampness, dusty environments, and housekeeping concerns. We recommend management review personal workspace rules and enforcement guidelines pertaining to blocking vents; food storage, preparation, and consumption areas; refrigerators; fish tanks; dehumidifiers; and fragrances.
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(2019) Lead and copper exposure at an indoor shooting range. (Click to open report) The Health Hazard Evaluation (HHE) Program received a management request from a government indoor shooting range because of concerns about employee exposure to lead and copper during cleaning activities. The facility contained three ranges. Two ranges used lead-based ammunition and one used frangible copper-based ammunition only. Employees were responsible for range cleaning in addition to maintenance activities, such as replacing exhaust fan filters and emptying buckets that collect bullets beh... (Click to show more)The Health Hazard Evaluation (HHE) Program received a management request from a government indoor shooting range because of concerns about employee exposure to lead and copper during cleaning activities. The facility contained three ranges. Two ranges used lead-based ammunition and one used frangible copper-based ammunition only. Employees were responsible for range cleaning in addition to maintenance activities, such as replacing exhaust fan filters and emptying buckets that collect bullets behind the bullet traps. During our evaluation, we toured the range facility, reviewed standard operating procedures and medical and training records, held confidential employee interviews, collected air and surface wipe samples for lead and copper and colorimetric wipe samples for lead, and evaluated the ventilation system. Four employees had lead exposures that were above the OSHA PEL when changing prefilters and emptying the bullet trap buckets. Employees wore respiratory protection while performing these tasks. However, NIOSH respirator selection guidance recommends a higher level of protection given the high lead concentrations we measured. One employee was above the OSHA action level for lead while performing cleaning. Two employees had blood lead levels > 5 ug/dL, a level NIOSH considers elevated. Air samples collected for total copper dust were lower than occupational exposure limits. Colorimetric wipes indicated lead and copper on surfaces within the facility. Although all employees were being monitored through the medical surveillance program and received training on lead exposure, they may benefit from more training on take-home lead. One range ventilation system was operating in accordance with NIOSH guidelines, one was lower than NIOSH guidelines, and one we were unable to evaluate because it was occupied with personnel firing weapons. We observed work practices that could contribute to lead exposure. Included in our recommendations were to provide periodic refresher training related to the standard operating procedures for each task and ensuring procedures are followed, ensure appropriate sizes for Tyvek suits and nitrile gloves are available, include take-home lead exposure information in annual training materials, provide work clothes that employees can launder and store at the workplace, and investigate possible changes to maintenance tasks involving filters and buckets.
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