Health Hazard Evaluations (HHEs)

(2008) Exposures to carbon monoxide and surface metals in an Ohio Department of Transportation District Garage. (Click to open report)
On August 15, 2006, NIOSH received a request from the OCSEA for a HHE at the ODOT District 8 Main Garage in Wilmington, Ohio. The OCSEA expressed concern about workplace exposure to CO from vehicle exhaust and exposure to metals such as arsenic, cadmium, and lead that may have accumulated on work surfaces over many years of garage operation. Two NIOSH investigators walked through the worksite on October 31, 2006, to become familiar with the facility and identify potential locations of surface co... (Click to show more) On August 15, 2006, NIOSH received a request from the OCSEA for a HHE at the ODOT District 8 Main Garage in Wilmington, Ohio. The OCSEA expressed concern about workplace exposure to CO from vehicle exhaust and exposure to metals such as arsenic, cadmium, and lead that may have accumulated on work surfaces over many years of garage operation. Two NIOSH investigators walked through the worksite on October 31, 2006, to become familiar with the facility and identify potential locations of surface contamination with metals. In a follow-up site visit on December 12, 2006, they measured instantaneous CO concentrations using direct reading instruments as the vehicles started-up and left the garage at the beginning of the work shift. They also collected surface wipe samples for arsenic, cadmium, lead, and other metals in work and non-work areas. Although only one of the two garage doors was open and only one of two exhaust fans was operating, all CO measurements were well below the NIOSH recommended ceiling limit of 200 ppm. The highest instantaneous CO concentration of 22.6 ppm occurred when a full-size pickup truck was started and driven out of the garage. Of all the CO measurements, 78% were less than 5 ppm. Because all measured CO concentrations were less than 23 ppm, it is expected that full-shift TWA concentrations would also be well below the NIOSH REL of 35 ppm. No arsenic was detected in any of the surface wipe samples that NIOSH investigators collected. Low concentrations of cadmium were detected on the workbench near the bench grinder in the vehicle maintenance bay and on the workbench near the chain saw sharpener. Cadmium was not detected in any of the other surface wipe samples. High concentrations of surface lead were detected on the bench grinder workbench and chain saw sharpener workbench, and low concentrations were detected on the other work surfaces sampled. Lead was either not detected or was found in trace concentrations on most non-work surfaces, except for low concentrations on the floor near the picnic tables and around the handle of a changing room locker. NIOSH investigators recommend cleaning the workbench surfaces with a HEPA filtered vacuum followed by wet cleaning of the bench surface after each day in which the chain saw sharpener or bench grinder are used. Other work surfaces should be periodically cleaned. Kitchen and break area eating surfaces should be cleaned each day. NIOSH investigators also recommend that employees store personal protective equipment in designated areas and that employees wash their hands thoroughly before eating, drinking, or smoking. (Click to show less)
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(2008) Headlee Roofing, Mesa, Arizona. (Click to open report)
On November 15, 2004, the National Institute for Occupational Safety and Health (NIOSH) received a request from the United Union of Roofers, Waterproofers, and Allied Workers Local 135 to conduct a health hazard evaluation (HHE) for employees of Headlee Roofing in Mesa, Arizona. The request listed silica and noise as potential hazards to roofers. This is one of four HHEs examining silica and noise exposures among roofers in Arizona. On January 11-13, 2005, NIOSH investigators conducted an HHE at... (Click to show more) On November 15, 2004, the National Institute for Occupational Safety and Health (NIOSH) received a request from the United Union of Roofers, Waterproofers, and Allied Workers Local 135 to conduct a health hazard evaluation (HHE) for employees of Headlee Roofing in Mesa, Arizona. The request listed silica and noise as potential hazards to roofers. This is one of four HHEs examining silica and noise exposures among roofers in Arizona. On January 11-13, 2005, NIOSH investigators conducted an HHE at a residential work site in Mesa, Arizona. Dust and noise measurements were taken during residential roofing operations. In addition, bulk samples of tile dust were collected to determine the silica content. NIOSH investigators selected four homes where employees were cutting and laying tiles throughout the day and took noise measurements and simultaneous full-shift personal breathing zone (PBZ) air samples for total and respirable dust. They also evaluated a saw equipped with local exhaust ventilation (LEV) and a saw not equipped with LEV typically used by the workers, using PBZ sampling and real-time monitoring of particle size and particle counts. Noise exposures for all seven roofers exceeded the NIOSH recommended exposure limit. Two employees exceeded the Occupational Safety and Health Administration (OSHA) permissible exposure limit, and all seven employees exceeded the OSHA action limit. The 8-hour time-weighted averages (TWA) for the total dust samples ranged from 1.2 to 5.4 mg/m3. The eight PBZ respirable dust concentrations ranged from 0.32 to 1.8 mg/m3, with a mean of 1.3 mg/m3. The 8-hour TWAs for respirable dust ranged from 0.2 to 1.8 mg/m3. Respirable silica samples ranged from 0.057 to 0.27 mg/m3, with a mean of 0.2 mg/m3. The respirable silica 8-hour TWAs ranged from 0.04 to 0.25 mg/m3. The LEV-equipped saw was not effective in reducing worker exposures to acceptable levels during cutting operations. Medical screening was conducted February 22-24, 2005. Employees from all four roofing companies were invited to participate if they had at least 5 years of experience as a roofer. The medical screening included a questionnaire, lung function test (i.e., spirometry), and a chest x-ray. Of the 118 employees who participated in all three tests, six were from Headlee Roofing. Most roofers who participated in the medical screening had normal lung function. None of those with abnormal lung function had moderate or severe impairments. After controlling for the effects of smoking, NIOSH investigators found that lung function decreased with increasing years of dry cutting cement tiles. No chest x-rays showed findings consistent with silicosis. NIOSH investigators determined that an occupational health hazard due to exposures to respirable silica and noise existed for employees of Headlee Roofing. Recommendations for controlling workplace exposures include reducing or eliminating exposures by implementing engineering controls and enforcing the use of personal protective equipment under the OSHA respirator program guidelines. The employer should develop a training program regarding the potential health hazards of respirable silica exposure and institute a medical monitoring program per the OSHA Special Emphasis Program for Silicosis. Additional recommendations are included at the end of this report. (Click to show less)
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(2008) Radiation exposure to TSA baggage screeners. (Click to open report)
Between November 2002 and March 2003, the National Institute for Occupational Safety and Health (NIOSH) received three health hazard evaluation (HHE) requests from Transportation Security Administration (TSA) employees at the Cincinnati, Honolulu, and Baltimore airports. The employees expressed concerns about a variety of potential exposures including diesel exhaust, dirt, dust, noise, and hazardous items found in baggage. In addition, a concern common to all three requests was exposure to x-ray... (Click to show more) Between November 2002 and March 2003, the National Institute for Occupational Safety and Health (NIOSH) received three health hazard evaluation (HHE) requests from Transportation Security Administration (TSA) employees at the Cincinnati, Honolulu, and Baltimore airports. The employees expressed concerns about a variety of potential exposures including diesel exhaust, dirt, dust, noise, and hazardous items found in baggage. In addition, a concern common to all three requests was exposure to x-rays from carry-on baggage and checked baggage screening machines. On March 26, 2003, TSA management submitted a separate request for NIOSH "to perform an independent study to determine the levels of radiation emissions from the various TSA screening equipment, and whether routine use of dosimetry is warranted." In May 2003, the following 12 airports were selected for study: Logan International (BOS); Baltimore-Washington International (BWI); Cincinnati/Northern Kentucky International (CVG); Los Angeles International (LAX); T.F. Green Municipal (PVD); Palm Beach International (PBI); Chicago O'Hare International (ORD); Harrisburg International (MDT); Honolulu International (HNL); McCarren International (LAS); Miami International (MIA); and Philadelphia International (PHL). The objectives of the NIOSH HHE were as follows: (1) assess the work practices, procedures, and training provided to TSA baggage screeners who operated machines that generate x-rays and (2) characterize TSA baggage screeners' radiation exposures and determine if routine monitoring with radiation dosimeters is warranted. Basic characterizations of work practices, spot measurements for radiation, and employee interviews were completed between August 2003 and February 2004. Monthly radiation measurements were obtained from personal dosimeters issued to TSA baggage screeners between March and August 2004. During the basic characterization phase, we observed poor work practices such as employees reaching into the Explosive Detection System (EDS) machines to clear bag jams and employees covering up the emergency stop buttons. We inspected and measured radiation exposure rates for 281 EDS machines. We observed that EDS machines at several airports exhibited a flaw that could be a source of unnecessary radiation exposure to TSA baggage screeners operating these machines. Radiation could leak out of the main gantry housing the computer-aided tomography (CAT) scanner through gaps between the entrance and exit baggage conveyors that appeared because the conveyor belt tunnels on most standalone units were not bolted to the gantry. Workers who frequently have to push odd-sized baggage up the entrance conveyor of the standalone machines are potentially exposed to the radiation present in the gap between the gantry and conveyor belt tunnel. We recommended taking six machines offline because the potential exposures to workers from these machines were equal to or greater than 500 microRoentgen per hour (uR/hour), the Food and Drug Administration's Performance Standard for cabinet x-ray systems. Occupational radiation measurements over a 6-month period from 854 TSA employees included 4024 results from dosimeters worn on the chest (as an estimate of exposure received by the whole body) and 3944 results from dosimeters worn on the wrist. Approximately 89% of the occupational whole body exposures and 88% of the occupational exposures to the wrist were below 1 millirem (mrem). None of the participants' doses in this evaluation exceeded the Occupational Safety and Health Administration (OSHA) permissible exposure limit of 1250 mrem per calendar quarter for individuals present in a restricted area (an area where access is controlled by the employer for purposes of protecting individuals from exposure to radiation or radioactive materials). Furthermore, no doses exceeded 25% of the OSHA quarterly limit which would require employee monitoring. The median estimated 12-month cumulative occupational whole body dose during the period of observation was zero at four of six airports. The highest median estimated 12-month cumulative occupational doses (whole body and wrist) occurred at LAX (14.7 and 15.5 mrem); the other airport with a non-zero median estimated 12-month cumulative dose was BOS (0.4 mrem each for whole body and wrist). Doses for only two out of 854 individuals exceeded the 500 mrem/year estimated cumulative occupational dose, which is the monitoring threshold of the National Radiation Council, and only 13 exceeded an estimated cumulative whole body or wrist dose of 100 mrem/year, which is the monitoring threshold of the Department of Energy. However, because the sample of airports may not be representative, and the study participants were volunteers, these results may not generalize to the entire TSA workforce. Given the strengths and weaknesses of this study, the need for a routine radiation dosimetry program for TSA screeners can neither be justified nor refuted at this time. Approximately 90% of the doses that screeners received were below 1 mrem, but some doses were at levels that warrant further action. Therefore, additional monthly or quarterly dosimetry targeted at specific airports for at least a year may be useful to evaluate the high doses reported in this evaluation. The number of airports and the specific airports for this targeted monitoring are left to the discretion of the TSA. Selection criteria could include airport size, machine type, and orientation of machines (in-line versus standalone). It is recommended that the dosimetry program be managed by a health or medical physicist. To address weaknesses of this study, we also recommend that TSA make participation in the dosimetry program mandatory. (Click to show less)
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(2007) COL-FIN Specialty Steel, Fallston, Pennsylvania. (Click to open report)
On February 27, 2003, the National Institute for Occupational Safety and Health (NIOSH) received a request from the United Steelworkers of America Local 9305 for a health hazard evaluation (HHE) at COL-FIN Specialty Steel (COL-FIN) in Fallston, Pennsylvania. The union was concerned about inadequate ventilation in the pickling and annealing areas and other potential health hazards throughout the whole plant. On November 11, 2003, NIOSH investigators made an initial visit to the facility to meet w... (Click to show more) On February 27, 2003, the National Institute for Occupational Safety and Health (NIOSH) received a request from the United Steelworkers of America Local 9305 for a health hazard evaluation (HHE) at COL-FIN Specialty Steel (COL-FIN) in Fallston, Pennsylvania. The union was concerned about inadequate ventilation in the pickling and annealing areas and other potential health hazards throughout the whole plant. On November 11, 2003, NIOSH investigators made an initial visit to the facility to meet with union and management representatives, tour the facility to understand the manufacturing process, and observe work practices. Between March 8 and March 12, 2004, NIOSH investigators returned to COL-FIN to conduct environmental sampling and medical interviews with employees. Area and personal breathing zone (PBZ) air samples for respirable particulates and acids (sulfuric and hydrochloric) were collected during the annealing, pickling, and hot etching of steel coils. Area and PBZ air samples for respirable particulates from soap powder and metal working fluids (MWFs) were collected when employees were drawing, straightening, and grinding the steel coils. Respirable particulate samples were also analyzed for crystalline silica. Spot measurements for carbon monoxide (CO) were taken in the annealing area. In addition, personal noise measurements were made on employees during the annealing, drawing, straightening, and grinding processes. Material handlers, who transport steel coils on gas-powered forklifts throughout the production area were assessed for exposure to noise, respirable particulates, silica, CO, and acids. A short-term sample for hydrochloric acid collected during the etching process exceeded the NIOSH and Occupational Safety and Health Administration (OSHA) ceiling limits; sulfuric acid levels were below all occupational exposure limits (OELs). Respirable particulate and silica levels were also below all OELs. Spot measurements for CO ranged up to 18 parts per million. Area and PBZ air samples collected in the grinding and shaving areas were above the NIOSH recommended exposure limit (REL) for MWFs; the local exhaust ventilation units for the grinding and shaving equipment were not functioning as intended. The personal noise dosimetry data showed that noise levels for two material handlers exceeded the OSHA action level of 85 decibels on an A-weighted scale. Many employees' noise levels also exceeded the more protective NIOSH REL. Thirty-five workers were interviewed. Many workers reported respiratory (66%) and skin problems (31%) consistent with exposure to MWFs and other occupational exposures. Over half of interviewed workers were current smokers. Smoking occurred throughout the plant, exposing non-smokers to secondhand smoke. Exposures to excessive levels of noise and MWFs, as well as exposure to secondhand smoke, constitute a health hazard at COL-FIN. Employees reported respiratory and dermal problems consistent with their occupational exposures. NIOSH investigators recommend enrolling COL-FIN employees in a hearing conservation program and banning smoking inside the facility. NIOSH investigators also recommend servicing the local exhaust ventilation units in the grinding and shaving areas to reduce exposure to MWFs and establishing a medical monitoring program for workers exposed to MWFs. (Click to show less)
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(2007) Highlights of the NIOSH health hazard evaluation: Copperhill smelter worker study. (Click to open report)
The union that represented some workers at the smelter asked NIOSH to study worker health. The union and people in the nearby community wanted to know if health problems were related to working in or living near the smelter. Although this study only included smelter workers, NIOSH thought the results would help answer questions about health in the community. Many people in the community worked at the smelter. Also, smelter operators had data about exposures in the plant. These data would help re... (Click to show more) The union that represented some workers at the smelter asked NIOSH to study worker health. The union and people in the nearby community wanted to know if health problems were related to working in or living near the smelter. Although this study only included smelter workers, NIOSH thought the results would help answer questions about health in the community. Many people in the community worked at the smelter. Also, smelter operators had data about exposures in the plant. These data would help researchers better understand whether smelter-related exposures were linked to health problems. Because a study of the smelter workers had been done in the 1980s, this study was possible. The researchers set the following four goals for the study: 1. Compare death rates and causes of death in smelter workers with those in the general population. 2. Describe the work environment in the smelter by work area, job title, and levels of exposure to six agents. 3. Describe the smoking history of smelter workers and use this information to help understand the cause-of-death results. 4. Examine whether specific causes of death were related to exposures in the smelter work setting. The study included 2,422 men who worked in the smelter, mill, or sulfur plant for 3 or more years between January 1946 and April 1996. For the years 1949 through 2000, the researchers found out whether these workers were living or deceased. If the workers were deceased, the researchers obtained information about their cause of death. The researchers used information from national and state records to learn whether people in the study had died. The researchers then obtained information about the causes of those deaths. They also used information from records in the smelter about the age, race, and sex of people in the study. They compared the number of deaths of smelter workers to the number that would be expected in groups of people who did not work in the smelter. These included the general population of the United States and the population of the counties around the smelter. They made these comparisons for all causes of death combined, for groups of diseases (such as all cancer or all lung disease), and for specific diseases (such as lung cancer or cerebrovascular disease, also known as stroke). They used statistical tests to decide if the results were meaningful. When they saw meaningful differences, they looked to see if death rates were related to exposure. They got exposure information from smelter records and by interviewing workers about smelter operations. To look at exposure, they grouped people by how long they worked in the plant, what department they worked in, their job title, and the level of exposure. They estimated exposure levels for lead, arsenic, cadmium, cobalt, dust, and sulfur dioxide based on records of workplace air sampling done by smelter operators. All causes of death. Of the workers in the study, 961 (41%) were deceased. Researchers found a cause of death for 878 of these. The total number of deaths expected among smelter workers was based on national and local county rates. For all causes of death, all types of cancer, all types of heart disease, respiratory disease other than cancer, and many of the specific causes of death, the rates in the surrounding counties were similar to the national rates. Cancer deaths. Of the workers in the study, 228 died of cancer. This was 18% lower than expected based on national rates and 16% lower based on local county rates. When specific types of cancer were looked at separately, some differences between smelter workers and the general population were found. Most of these differences were based on numbers of deaths so small they were not thought to be important. Eleven workers died of cancer of the central nervous system, an excess of 39% compared to the general population. By statistical tests, this difference was not meaningful. Noncancer deaths. The results did not show that smelter workers had a meaningful increase in the risk of death from any other cause of death. Levels of exposure. The average exposure levels for lead and sulfur dioxide were close to the current workplace limits for these agents. For arsenic, cadmium, cobalt, and dust, the past average exposure levels were much lower than current limits. Causes of death and exposure. After examining all causes of death and all measures of exposure, the researchers looked at two findings more closely. These were the link between arsenic exposure and stroke and the link between cadmium exposure and bronchitis. Stroke and arsenic exposure. Seventy workers died of stroke. The risk of death from stroke was higher for people who worked longer and for people with more arsenic exposure. By statistical tests, this difference was not meaningful. For example, workers with the highest level of total exposure were 1.5 times more likely to die of stroke than unexposed workers, but the p value, a measure of significance, was 0.17; a p value of 0.05 or less is regarded as statistically significant. Bronchitis and cadmium exposure. Seven workers died of bronchitis. The risk of bronchitis death was higher for some exposed workers than for unexposed workers. This finding, however, was not the same for all exposure groups or measures. For example, workers with a moderate level of total cadmium exposure were 14.8 times more likely to die of bronchitis than unexposed workers. But, workers with the highest level of exposure were only 3.8 times more likely to die of bronchitis. The p value for these findings was 0.06, not statistically significant. As with most studies of this type, some factors make it hard for researchers to draw firm conclusions about the findings. First, because complete and accurate information about cigarette smoking was not available, the researchers could not investigate how cigarette smoking affected causes of death. But, it is unlikely that this limitation had an important effect on the conclusions. Second, this study was smaller than studies of other workplaces. The small size makes it less likely that the findings will be statistically significant, even if there is a real risk. Because of this, it is helpful to look at the how the findings of this study fit in with the findings of other studies of smelter workers or of other workers with similar exposures. Death rates for Copperhill smelter workers were lower than expected for all causes of death and from specific cancer and noncancer causes. This is not an unusual finding in studies of workers. So, researchers looked to see if workplace exposures were related to the risk of death from specific causes. One finding of interest was for arsenic and stroke. Another was for cadmium and bronchitis. The researchers concluded it is unlikely that arsenic exposure caused increased stroke risk or that cadmium exposure caused increased bronchitis disease risk in Copperhill workers. This conclusion is based on the detailed analyses of the findings from this study and on evidence from other studies about these exposures and diseases. It is also important to note that other studies of smelter workers have shown that arsenic exposure is related to respiratory cancer. Arsenic exposures in the Copperhill smelter were lower than in other smelters studied. The researchers in this study did not see an increase in respiratory cancer risk. (Click to show less)
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