Health and Safety Programs for Construction Work--Painter Training Evaluation Project
This three-year study compared the effect of training on knowledge and on-the-job health protective behaviors of construction painters in three states. Alaska has a mandatory certification program for painters. Oregon has a voluntary training program; and Washington has no specific training requirements for painters. Questionnaires were mailed to 3,000 painters in the three states. Painters in Alaska reported more knowledge of health hazards and safe work practices than did painters in Oregon and Washington. The project focused on characteristics of the Alaska training program that account for the apparent differences in safety behavior and knowledge between Alaskan painters and those from Washington and Oregon. Painter subjects were randomly assigned to an Alaska-type training course or a training course developed by their trade association. Painter knowledge and self-reported painting behaviors immediately and three months after the course were compared.
Lead Exposure Assessment in Construction
This was a two-phase project involving two graduate student theses. In the first phase, data were collected and interpreted on exposure to airborne lead in workers performing various construction and demolition activities. These data were used to create a predictive exposure model that would help forecast potential, and reconstruct past, worker exposures. Lead exposures were evaluated and compared for four primary work activities: demolition/renovation work, abrasive blasting, paint removal, and welding and torch cutting. The second phase validated the original model.
Assessment of Occupational Noise Exposures in Four Construction Trades
In this study, noise exposure samples were collected from construction workers employed by a general contracting company in four construction trades: carpenters, laborers, ironworkers, and operating engineers. Workers completed a questionnaire detailing the timing, number of tasks performed, and tools used throughout the day. Trade was a poor predictor of noise exposure; construction method, stage of construction, and the work tasks and tools used were found to be better predictors. The mean OSHA time-weighted average (TWA) for 338 samples was 82.8 dBA while the mean NIOSH/ISO TWA for 174 samples was 89.7 dBA. Forty percent of OSHA TWAs exceeded 85 dBA, and 13% exceeded 90 dBA, the OSHA permissible exposure level. The highest exposure levels were those involving pneumatically operated tools and heavy equipment. An internal validation sub-study indicated excellent agreement between worker-reported and researcher-documented tasks and tools.
Neitzel R, Seixas NS, Camp J, Yost M. An assessment of occupational noise exposures in four construction trades. Am Ind Hyg Assoc J. 1999 Nov-Dec;60(6):807-17.
Review of Construction Crane Safety
Cranes account for about one-third of all construction and maintenance fatalities. Safety and health professionals serving the construction industry need adequate training and knowledge about available crane safety devices and procedures in order to ensure these techniques are used effectively. This paper reviews available information on crane-related injuries, currently available safety devices, and commonly used crane safety procedures and gives recommendations for improved crane injury prevention and future crane safety research.
Neitzel RL, Seixas NS, Ren KK. A review of crane safety in the construction industry. Appl Occup Environ Hyg. 2001 Dec;16(12):1106-17
Noise Exposures in Electrical Trades
Noise dosimetry was used to assess the exposure levels of electricians working for a major electrical subcontractor. Five sites that used four construction methods were visited. Electricians documented activity and environmental data throughout their work shifts, resulting in an activity/exposure record for each of the 174 samples collected. More than 24% of the 174 full-shift exposure samples exceeded the current Washington state (WISHA) permissible exposure level (PEL) of 85 dBA; 5.2% exceeded the federal OSHA PEL of 90 dBA. When measured with a NIOSH exposure metric, 67.8% exceeded 85 dBA and 27% exceeded 90 dBA. The WISHA maximum instantaneous exposure level of 140 dBA was exceeded in 99.4% of samples. Pneumatic power tools, power-actuated tools, and the hand hammer resulted in the highest exposures among tools used by electricians. Results of the study indicate electricians are at risk of developing noise-induced hearing loss, their exposures are affected by adjacent activity, and engineering controls can reduce exposure levels.
Seixas NS, Ren K, Neitzel R, Camp J, Yost M. Noise exposure among construction electricians. AIHAJ. 2001 Sep-Oct;62(5):615-21.
Evaluation of Equipment with Dust Control for Concrete Grinding
Sampling was conducted to assess silica and respirable dust exposures to masons during work on a campus library. Initial exposures were above the Washington state 8-hour permissible exposure levels. Dust control measures, consisting of a vacuum and shrouded grinders, were then installed and exposures were resampled. After use of dust control, exposures were significantly reduced. It was concluded that, with these measures, exposures were low enough that a half-face air-purifying respirator with a HEPA filter could replace the powered air-purifying respirator.
Dust Control During Mason Cleanup
Cleanup on construction projects can produce significant dust and silica exposure. At the International Masonry Institute apprenticeship training facility, two dust control strategies were evaluated during cleanup activities: 1) use of sweeping compound to reduce dust during sweeping; and 2) use of squeegees rather than brooms and an industrial vacuum with HEPA filtration to remove dirt piles. Personal exposures were lower with sweeping compound than without controls, and lower with a squeegee/vacuum system than with sweeping compound.
Engineering Controls for Silica Dust
This NIOSH-funded study assessed the effectiveness of commercially available local exhaust ventilation (LEV) systems for controlling respirable dust and crystalline silica exposures during concrete cutting and grinding activities. In a randomized block design, implemented under controlled field conditions, three ventilation rates (0, 30 and 75 CFM) were tested for each tool and LEV system used by workers engaged in tuck point grinding a brick wall, surface grinding a concrete wall, cutting paver block and brick, and cutting concrete block. With the exception of the hand-held saw, the use of LEV resulted in a significant reduction in respirable dust exposure, although exposures remained 0.5 to 2.5 times the permissible exposure level. Nonetheless, this dust control alternative reduces the risk of workers developing disease, allows workers to use a lower level of respiratory protection, protects workers during short duration work episodes, reduces exposure to nearby workers, and reduces cleanup-associated dust exposures.
G. Croteau, S. Guffey, M. Flanagan, and N. Seixas. The Effect of Local Exhaust Ventilation Controls on Dust Exposures During Masonry Activities. AIHA Journal 63:458–467 (2002)
Wet Concrete Sawing and Drilling
Two concrete cutting and drilling companies were interested in characterizing workplace exposures to silica and respirable dust so they could develop or enhance existing respiratory protection policies. The study was conducted at ten different construction sites. Four tools were evaluated: walk-behind and hand-held slab saws, core drill, and wall saw. The 8-hour exposures for the 13 samples were found to be at or above the permissible exposure level in five cases. Water appeared to be effective in reducing emissions during concrete cutting and drilling. However, the potential for overexposures to silica when working in an enclosed environment still existed, both for the tool operator and adjacent workers. Therefore, when cutting concrete inside using water for dust suppression, this study recommended that saw operators and others in the area wear respiratory protection.
Flanagan ME, Loewenherz C, Kuhn G. Indoor wet concrete cutting and coring exposure evaluation. Appl Occup Environ Hyg. 2001 Dec;16(12):1097-100.
FRCG Quarry Sampling Summary Report
The FIELD GROUP developed a summary report of sampling results for noise and silica at 10 open surface mines. Samples were collected across all seasons for a year. Employees who had a potential for exposure to noise or silica dust were monitored. For all eight jobs monitored, the mean 8-hour noise exposure exceeded 85 dBA. The exposure of only groundsmen exceeded 90 dBA, although crusher mechanics had exposures approaching this limit. For silica exposure, only groundsmen had a mean exposure at the silica permissible exposure level of 10 mg/m3. Recommended controls included fitting heavy equipment with cabs and air conditioning, fitting generators with supply and exhaust air mufflers, upgrading conveyor belts to reduce the need for belt cleaning by a groundsman, soundproofing the crusher operator's booth, and shifting groundsmen's work schedules to reduce their time near operating equipment.
Silica Dust Exposures During Selected Construction Activities
Eight common construction tasks were evaluated for quartz and respirable dust exposure. The geometric mean quartz concentration was 0.10 mg/m3, with 71% exceeding the threshold limit value. Activities with the highest exposures were surface grinding, tuck-point grinding, and concrete demolition. Factors important to exposure included tool used, work area configuration, controls employed, cross draft, and in some cases nearby dust. Respiratory protection was found to be inadequate for 42% of exposures. Exposures were reduced by using a box fan for surface grinding and floor sanding, and a vacuum/shroud for surface grinding, with reductions of 57, 50, and 71%, respectively. The study concluded that the usual protection method, respirators, was not always adequate, and the use of engineering controls was infrequent and often ineffective.
Flanagan M.E., N. Seixas, M. Majar, J. Camp, M. Morgan. Silica Dust Exposures During Selected Construction Activities. AIHA Journal 64:319–328 (2003).
The Efficacy of Local Exhaust Ventilation for Controlling Dust Exposures During Concrete Surface Grinding
This study assessed the effectiveness of a commercially available local exhaust ventilation (LEV) system for controlling respirable dust and crystalline silica exposures during concrete grinding activities. Three different dust collection shroud configurations were tested during surface grinding by cement masons at six commercial construction sites. Data obtained with a direct reading respirable dust monitor were adjusted to remove non-work task-associated dust exposures and were subsequently used to calculate the exposure reduction achieved. The application of LEV resulted in a reduction in the overall geometric mean respirable dust exposure from 4.5 to 0.14 mg/m3, a mean exposure reduction of 92%. Despite the effective control of dust generated during surface grinding, 22% of the samples collected while LEV was being used were greater than the 8 hour time-weighted average permissible exposure limit, and 26% greater than the threshold limit value for respirable crystalline silica.
Croteau G., M. E. Flanagan, J. Camp and N. Seixas..The Efficacy of Local Exhaust Ventilation for Controlling Dust Exposures During Concrete Surface Grinding. Annals of Occupational Hygiene 2004 48(6):509-518.
Development of an ACGIH Construction Industry Silica Exposure Database Overview
A silica monitoring data compilation project was initiated through the American Conference of Governmental Industrial Hygienists Construction Committee. Personal silica exposure monitoring data was collected and analyzed from 13 private, research and regulatory groups. An effort was made to collect as much information as possible about task, tool, environmental and control conditions. Results from 1,374 personal quartz samples reported had a geometric mean (GM) of 0.13 mg/m3 and a GSD of 5.9. Highest exposures were reported for abrasive blasters, surface and tuckpoint grinders, jackhammers, and rock drills. Results were considerably higher for short term samples (up to 2 hours) than for mid term (2-6 hours) or longer (over 6 hour) samples. For nearly all exposure variables, a large portion of variable categories were at or over the quartz occupational exposure limit of 0.05 mg/m3. The data variability within task and tool was very large, with some very high exposures reported for a broad spectrum of tools. These results indicate that respiratory protection commonly used on construction sites is often inadequate for the exposures encountered. Further understanding of the conditions leading to high exposures will require more detailed documentation of the sample characteristics following database design recommendations or systematic surveys of exposure in this complex industry.
Development of an ACGIH Construction Industry Silica Exposure Database Overview
Silica Exposures in Construction: What Workers Need to Know
This website describing silica exposure is targeted towards construction. It recommendeds the use of respirators for eight common construction tasks.