Health Hazard Evaluations (HHEs)

(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)
(Click to open report)

(2006) Transportation Security Administration: Palm Beach International Airport, West Palm Beach, Florida. (Click to open report)
On July 22, 2004, the National Institute for Occupational Safety and Health (NIOSH) received a health hazard evaluation (HHE) request from the Transportation Security Administration (TSA) at the Palm Beach International Airport in West Palm Beach, Florida. The HHE request asked NIOSH to determine the potential for exposure to heat stress conditions for screeners working in the checked baggage screening area. The request indicated that some employees had experienced health problems possibly relat... (Click to show more) On July 22, 2004, the National Institute for Occupational Safety and Health (NIOSH) received a health hazard evaluation (HHE) request from the Transportation Security Administration (TSA) at the Palm Beach International Airport in West Palm Beach, Florida. The HHE request asked NIOSH to determine the potential for exposure to heat stress conditions for screeners working in the checked baggage screening area. The request indicated that some employees had experienced health problems possibly related to heat stress, including heat cramps and heat exhaustion. In response to the request, NIOSH investigators conducted heat stress and heat strain monitoring on August 28-31, 2004. Wet bulb globe temperatures (WBGT) were measured to evaluate the heat stress conditions. Individual heat strain was assessed using core body temperature (CBT), heart rate (HR), and pre- and post-shift body weight measurements. WBGT readings ranged from 77.5 degrees F to 83.9 degrees F in the checked baggage screening area. When compared to the NIOSH and American Conference of Governmental Industrial Hygienists (ACGIH) screening criteria, the results indicate that the screeners were exposed to excessive heat stress conditions during the evaluation. Twenty-three participants were monitored for physiological signs of heat stress during their work shifts. All employees were considered acclimatized to their work environment during the evaluation. Eight participants (35%) showed signs of heat strain. One of the screener's CBT exceeded the ACGIH criterion of 101.3 degrees F for acclimatized workers. There were 10 instances of screeners' HRs exceeding the ACGIH criterion of 180 minus their age. In addition, three of the screeners had average HRs that approached or exceeded 115 beats per minute (bpm) during the shifts they were monitored. None of the screeners had a body weight loss of more than the ACGIH criterion of 1.5%. TSA screeners working in the checked baggage screening area were exposed to heat stress in excess of the occupational screening criteria. Some employees developed signs of heat strain as measured by CBT or sustained HR. In addition, some complained of symptoms of heat strain. Recommendations for identifying and reducing heat stress and strain are provided in this report. (Click to show less)
(Click to open report)

(2005) Transportation Security Administration, Baltimore-Washington International Airport (BWI), Linthicum, Maryland. (Click to open report)
On January 21, 2004, the National Institute for Occupational Safety and Health (NIOSH) received a health hazard evaluation (HHE) request from the Transportation Security Administration (TSA) at the Baltimore-Washington International Airport (BWI) in Linthicum, Maryland. The HHE request concerned potential health hazards among TSA workers in the "checked" baggage screening areas from exposure to contaminants found in exhaust emissions of tug and jet engines and noise from tugs, jets, conveyor sys... (Click to show more) On January 21, 2004, the National Institute for Occupational Safety and Health (NIOSH) received a health hazard evaluation (HHE) request from the Transportation Security Administration (TSA) at the Baltimore-Washington International Airport (BWI) in Linthicum, Maryland. The HHE request concerned potential health hazards among TSA workers in the "checked" baggage screening areas from exposure to contaminants found in exhaust emissions of tug and jet engines and noise from tugs, jets, conveyor systems, and baggage carousels in the checked baggage screening area. Reported health problems included respiratory distress, dizziness, possible hearing loss, and headaches. An initial site visit was made on April 1, 2004. On July 15-16, 2004, NIOSH investigators conducted area and personal breathing zone (PBZ) air samples for carbon monoxide (CO), nitrogen dioxide (NO2), nitric oxide (NO), diesel exhaust particulate (measured as elemental carbon [EC]), and volatile organic compounds (VOCs). Fullshift personal noise monitoring was also conducted. Concentrations of EC, a surrogate for diesel exhaust, ranged from 4 micrograms per cubic meter (microg/m3) to 24 microg/m3 with an airport-wide average of 11 microg/m3. There is no NIOSH evaluation criterion for EC; however, the California Department of Health Services recommends keeping exposure levels below 20 microg/m3. PBZ concentrations of NO2 and NO ranged from "trace" to 0.19 parts per million (ppm). Area air samples of NO2 and NO collected in the vicinity of workers ranged from "trace" to 0.13 ppm. Nondetectable NO2 results (<0.1 ppm) were obtained from real time personal exposure monitors (full-shift and 15-minute short-term exposures) and were in agreement with the other method used to measure NO2 exposure. PBZ exposure for CO ranged from non-detectable (<0.1 ppm) to 2 ppm (full-shift Time-Weighted Average [TWA]) and from non-detectable to 3 ppm (15-minute short-term exposures). Instantaneous peak values ranged from 2 to 221 ppm. Exposure to VOC's, including isopropanol and toluene, were very low. Noise dosimetry results indicated no appreciable risk for occupational noise induced hearing loss at BWI. However, a few areas (i.e., Air Tran and Delta) do have noise levels that are high enough to warrant further evaluation. The NIOSH investigators determined that a hazard does not exist from exposure to EC, CO, CO2, NO2, NO or VOCs. The sampling results indicate that, on average, none of the exposures exceeded occupational exposure limits. The measured noise levels provide little evidence of a serious noise problem. Recommendations for maintaining the air quality and further reducing noise exposures are provided in the Recommendations Section of this report. (Click to show less)
(Click to open report)

(2004) Transportation Security Administration-Miami International Airport, Miami, Florida. (Click to open report)
On February 20, 2004, the National Institute for Occupational Safety and Health (NIOSH) received a health hazard evaluation (HHE) request from the Transportation Security Administration (TSA) at the Miami International Airport in Miami, Florida. The HHE request concerned potential health hazards from exposure to contaminants found in exhaust emissions of tug and jet engines and noise from tugs, jets, conveyor systems, and baggage carousels in the checked baggage screening area. Reported health p... (Click to show more) On February 20, 2004, the National Institute for Occupational Safety and Health (NIOSH) received a health hazard evaluation (HHE) request from the Transportation Security Administration (TSA) at the Miami International Airport in Miami, Florida. The HHE request concerned potential health hazards from exposure to contaminants found in exhaust emissions of tug and jet engines and noise from tugs, jets, conveyor systems, and baggage carousels in the checked baggage screening area. Reported health problems included headaches, dizziness, and respiratory distress. An initial site visit was made on March 25, 2004; on June 5-6, 2004, NIOSH investigators conducted area and personal breathing zone (PBZ) air sampling for carbon monoxide (CO), nitrogen dioxide (NO2), nitric oxide (NO), diesel exhaust particulate (measured as elemental carbon [EC]), and volatile organic compounds (VOCs). Full-shift personal noise monitoring was also conducted. Concentrations of EC, a surrogate for diesel exhaust, ranged from 5.9 micrograms per cubic meter (microg/m3) to 19.2 microg/m3. No evaluation criteria exist for EC alone, although the California Department of Health Services recommends keeping levels below 20 microg/m3. PBZ concentrations of NO2 determined using sorbent tubes ranged from <0.1 part per million (ppm) to 0.12 ppm and PBZ concentrations of NO ranged from <0.05 ppm to 0.10 ppm. These results were very similar to the NO2 results obtained from real-time personal exposure monitors; full-shift time-weighted average (TWA) exposures were all non-detectable and 15-minute short-term exposures ranged from 0.1 ppm to 0.4 ppm. One employee's instantaneous exposure of 4.9 ppm approached the Occupational Safety and Health Administration (OSHA) ceiling limit of 5 ppm. All personal full-shift TWA exposures for CO ranged from 2 ppm to 7 ppm and 15-minute short-term exposures ranged from 5 ppm to 32 ppm. One employee working at the concourse C International to International (CITI) bag area measured an instantaneous peak exposure of 333 ppm. This employee's TWA and short-term exposure limit (STEL) exposures were 7 ppm and 32 ppm respectively. The employee's exposure to CO exceeded the NIOSH Ceiling limit of 200 ppm. VOCs were identified via thermal desorption tubes and quantified via charcoal tubes. One thermal desorption sample collected in Ramp A had significantly more VOC's present than any other sample. Only low levels of any contaminants were detected on all other samples. Compounds identified were isopropanol, benzene, ethyl benzene, xylenes, toluene, isooctane, and trimethyl benzenes. Charcoal tube analysis found low levels of isopropyl alcohol and toluene. Airborne concentrations of benzene, ethyl benzene, xylenes, isooctane, and total hydrocarbons were either not detected or were below the laboratory limit of quantification. The OSHA Permissible Exposure Limit (PEL) for noise of 90 A-weighted decibels (dBA) and the OSHA Action Level [85 dBA] were not exceeded in any of the 13 dosimeter samples. There were four instances where the 8-hr TWA exposures exceeded the NIOSH criterion, once on Saturday in area F2 and three times on Sunday in the EITI area (1) and at Area 62 (2). OSHA previously performed a noise survey in Area 62 and found 8-hr TWA levels of 88 dBA. These results were not confirmed in the NIOSH evaluation. The NIOSH investigators determined that a hazard does not exist from exposure to EC, CO, CO2, NO2, NO, or VOCs. The sampling results indicate that none of the chemicals were detected at concentrations exceeding occupational exposure limits. Therefore, an inhalation hazard to those compounds did not exist at the time of the NIOSH visit. The measured noise levels found little evidence of a serious noise problem. Recommendations for maintaining the air quality and reducing employees' noise exposures are provided in the Recommendations Section of this report (Click to show less)
(Click to open report)