Residential Construction Sites Research Articles

Changes in fall prevention training for apprentice carpenters based on a comprehensive needs assessment

Problem Falls from heights in residential construction are common, especially among inexperienced workers. Methods We conducted a comprehensive needs assessment to determine gaps in the school-based apprentice carpenters' fall prevention training. A team of carpenter instructors and researchers revised the fall prevention training to fill these gaps. Apprentice evaluation and feedback guided ongoing curricular improvements. Results Most apprentice carpenters performed work tasks at heights prior to training and fall protection techniques were not commonly used at residential construction sites. Priorities of the revised school-based training included safe ladder habits, truss setting, scaffold use, guarding floor openings, and using personal fall arrest systems. New apprentices were targeted to ensure training prior to exposure at the workplace. We used adult learning principles to emphasize hands-on experiences. A framed portion of a residential construction site was fabricated to practice fall protection behaviors in a realistic setting. The revised curriculum has been delivered consistently and apprentice feedback has been very favorable. Conclusions Integration of needs assessment results was invaluable in revising the school-based carpenters apprentice fall prevention curriculum. Working closely with the instructors to tailor learning experiences has provided preliminary positive results. Impact on Industry The fall safety of the residential construction industry continues to lag behind commercial construction and industrial settings. The National Occupational Research Agenda includes a Strategic Goal to strengthen and extend the reach of quality training and education in the construction industry via mechanisms such as construction safety and health training needs assessments. This study demonstrates how a structured process can be used to identify and remedy gaps and improve training effectiveness. We encourage others to take steps to assess and increase the impact of training efforts directed at all residential construction professionals; including both union and non-union workers. The implications are even greater in the non-union sector where most U.S. residential work is done.

Fall hazard control observed on residential construction sites

Falls are a leading cause of mortality and morbidity in the construction industry. This study measured fall hazards at residential construction sites. Trained carpenters administered the St. Louis Audit of Fall Risks and interviewed carpenters. The prevalence of fall prevention practices meeting safety criteria was counted and correlations explored. We identified a high prevalence of fall hazards at the 197 residential sites audited. Roof sheathing met safety criteria most consistently (81%) and truss setting least consistently (28%). Use of personal fall arrest and monitoring of unguarded floor openings were rare. Safer performance on several scales was correlated. Construction sites of large-sized contractors were generally safer than smaller contractors. Apprentice carpenters were less familiar with their employers' fall prevention plan than experienced workers. Safety could be improved with consistent use of recognized fall prevention practices at residential construction sites.

Minimum Formwork Stock problem on residential buildings construction sites

The Minimum Formwork Stock problem (MFS) consists in minimizing the quantity of shuttering materials needed for a construction site. This paper introduces this problem encountered in a French building company and presents two different solving approaches: a constraint programming model combined with a constructive heuristic and a Dantzig–Wolfe decomposition taking advantage of the size of real world instances. Then, a NP-hardness proof of the problem is established before providing results on real instances.

Development of the St. Louis Audit of Fall Risks at Residential Construction Sites

We describe the development and pilot testing of the St. Louis Assessment of Fall Risks, a worksite audit to assess fall prevention safety practices on residential construction sites. Surveillance data and feedback from carpenters and safety instructors regarding work tasks associated with falls from heights were used to develop the audit instrument. The audit focuses on the framing process, including general safety climate/housekeeping, floor joist/sub-floor installation, walking surfaces/edges, wall openings, truss setting, roof sheathing, ladders, scaffolds, and personal fall arrest equipment. The audit was tested at sixteen residential construction sites, documenting excellent inter-rater reliability (kappa = 0.93). Results suggest that the audit has good face and content validity and is a reliable instrument for measuring fall safety risks at residential construction sites. It is practical, easy, and safe to administer, making it a potentially useful instrument for field research as well as regular safety monitoring by foremen and crew.

Visual Analysis and Semantic Exploration of Urban LIDAR Change Detection

AbstractMany previous approaches to detecting urban change from LIDAR point clouds interpolate the points into rasters, perform pixel‐based image processing to detect changes, and produce 2D images as output. We present a method of LIDAR change detection that maintains accuracy by only using the raw, irregularly spaced LIDAR points, and extracts relevant changes as individual 3D models. We then utilize these models, alongside existing GIS data, within an interactive application that allows the chronological exploration of the changes to an urban environment. A three‐tiered level‐of‐detail system maintains a scale‐appropriate, legible visual representation across the entire range of view scales, from individual changes such as buildings and trees, to groups of changes such as new residential developments, deforestation, and construction sites, and finally to larger regions such as neighborhoods and districts of a city that are emerging or undergoing revitalization. Tools are provided to assist the visual analysis by urban planners and historians through semantic categorization and filtering of the changes presented.

Production of a noise level database of power tools used in the construction industry

This study focused its efforts on sound power levels and noise reduction of power tools used by workers at both commercial and residential construction sites. The objective was to develop a noise control technology database consisting of power hand tools used in the construction industry with respective sound power levels and workers’ sound exposure level (SEL). The database and specific noise control applications information are made available to the public on a searchable web-site. Data includes a particular tool’s wavfile and time series signatures to be used for future qualitative and quantitative analysis by other acousticians accessing the database. With this information, reasonable assumptions can be made as to the potential occupational noise exposure expected for various occupations, tasks, etc. and as to potential sources of noise within the powered hand tool itself. The database captures tool types, tool models, tool manufacturers, and decibel power level. The database is expandable to include new tools and new manufacturers as the power tool population changes over time. These efforts support the reduction of noise induced hearing loss among construction workers by providing ‘‘buy quiet’’ and ‘‘designed quiet’’ information to power tool buyers and end users.

Construction work practices and conditions improved after 2-years' participation in the HomeSafe pilot program.

This study reevaluated changes in job-site safety audit scores for a cohort of residential construction workers that had protracted exposure to the HomeSafe pilot program for 2(1/2) years. The investigation was a repeated measure of a cohort study underway in the six-county metro area of Denver, Colo. The larger study was a longitudinal, quasi-experimental design with a cohort of residential construction workers within the HomeSafe strategic partnership between Occupational Safety and Health Administration Region VIII and the Home Builders Association of Metropolitan Denver (HBA). Audits were conducted on residential construction sites. Study subjects were construction workers employed by partner or control companies within the study. Repeated measures of 41 companies showed significant improvement (p=.01) in audit scores, increasing from 71.8 to 76.8 after 2(1/2) years in the program. HomeSafe companies out-performed controls (p=.01) for both the retest group and previously unaudited HomeSafe companies. Prolonged exposure in the HomeSafe pilot program resulted in improved audit scores for companies within the program for at least 2 years.

Forensic Analysis Of Leaning/Falling Gypsum Wallboard

Gypsum Wallboard Is A Very Common Material Used In Residential And Commercial Construction. It Is Relatively Inexpensive To Purchase And Install. However, If Not Properly Stored On Site Prior To Its Installation, It Can Be A Source Of Property Damage, Injury, And Sometimes Death To The Layperson. The Author Has Over Thirty Years Experience Using Drywall In Residential And Commercial Construction. In That Time, The Author Has Known Of, And Has Been Personally Involved In Several Drywall Incidents. Fortunately, The Injuries, If Any, Were Inconsequential. The Experienced Construction Personnel Involved In Those Incidents Were Able To React To The Known Danger. It Is When The Layperson Comes Onto A Construction Site That Leaning Drywall Can Be Dangerous. This Paper Will Discuss The Results Of An Investigation Into The Death Of A 54 Year Old Woman (Plaintiff) On A Residential Construction Site In The Year 2000. The Plaintiff Was The Mother Of The Man Purchasing The New Residence. Both Were At The Incident Site To Inspect The Construction Progress. The Plaintiff Was Killed When Approximately Twenty-Six Sheets Of 4 x 12 x 1/2 Drywall Fell From A Leaning Position And Pinned Her Against The Interior Wood Structural Framing. The Investigation Involved An On-Site Inspection Where The Incident Took Place, Load Calculations, And The Review Of Numerous Depositions.

Exposure to wood dust and heavy metals in workers using CCA pressure-treated wood.

Chemical pesticide treatment enables relatively nonresistant woods to be used in outdoor construction projects. The most prevalent procedure used to protect these woods is pressure treatment with chromium, copper, and arsenic (CCA). This pilot study examined the airborne concentration and particle size distribution of wood particles, chromium, copper, and arsenic at both outdoor (measured over the whole work day) and indoor (measured during the performance of specific tasks) work sites. At the outdoor residential deck construction sites, the arithmetic mean total dust concentration, measured using personal filter cassette samplers, was 0.57 mg/m3. The mass median aerodynamic diameter (da) of the outdoor wood dust was greater than 20 microm. Indoor wood dust concentrations were significantly greater than those measured outdoor and were job category-dependent. The highest mean breathing zone dust concentration, 49.0 mg/m3, was measured at the indoor sanding operation. Personal impactor sampling demonstrated that the mean total airborne concentration of arsenic, but not chromium or copper, was consistently above recommended occupational exposure levels at the indoor work site, and occasionally at the outdoor work sites. At the indoor sanding operation, the mean total chromium, copper, and arsenic concentrations were 345, 170, and 342 microg/m3, respectively. Thus, significant exposure to airborne heavy metals can occur as a result of indoor and outdoor exposure to CCA pressure-treated wood dust. Therefore, current standards for wood dust may not adequately protect workers from the heavy metals commonly used in CCA pressure-treated wood.

Recycling durable vinyl products

AbstractThis is a description of the key aspects that have made a vinyl siding recycling project in Grand Rapids, Michigan, successful to date. Although Grand Rapids is hoped to be a template for other recycling projects there are some unique parts of the project that other regions of the country or even the city next door to Grand Rapids may not be able to duplicate. It would not be advisable at this point in time to advocate a nation‐wide vinyl siding recycling program based on the early results from Grand Rapids. On the other hand, the day may come when recycling the waste from residential construction sites (including the vinyl products) will be more widespread. At any rate, what Grand Rapids has proven is that vinyl as a material is ready for recycling.

Sediment and Nutrient Yield from Residential Construction Sites

AbstractRunoff from three residential construction site watersheds in southeastern Wisconsin was monitored for a 2‐year period. Automatic water quality monitoring equipment was established which sampled each event proportional to flow. Loading rates for sediment and nutrients were developed on an event basis and summed to produce annual loads.Concentrations for suspended solids (SS), organic plus exchangeable N [(Or + Ex)‐N], and total P preceded and paralleled the flow rate during runoff events. With the exception of nitrate plus nitrite nitrogen (NO3 + NO2)‐N, the soluble water quality parameters were independent of flow. Commonly, the (NO3 + NO2)‐N concentration was 1.0 mg/liter and varied inversely proportional to flow. The most common concentrations of dissolved phosphorus and ammonium were 0.05 and 0.10 mg/liter, respectively.Average sediment yield for the three single land use watersheds was 19.2 metric tons /ha per year. Concentrations of 60,000 mg/liter SS were observed for major events; 15,000 to 20,000 mg/liter were common for moderate events. Regression analyses of several independent variables identified flow (Q) as the single most important variable examined for explaining sediment load. Considered in combination, the product of flow and flow rate (Qqp) best explained sediment yield (r2 = 0.62).Yields of contaminants from residential construction sites are inherently variable and site dependent. Strict extrapolation or comparison of results to other areas or existing literature values is difficult. However, when compared to runoff data from a simultaneous agricultural watershed investigation, the yield of contaminants from construction sites is considerably higher (19.2 vs. <1 metric ton/ha per year of sediment).

Lidar evidence of thermal plumes in an urban environment

Abstract A laser radar (lidar) operating at the ruby line 0.6943 μm has been observing horizontal profiles of particulate concentration in the air some 30 m above the surface within the city of London over a period of one year. Anomalous features in these profiles are interpreted as natural thermal plumes carrying particles upwards from surfaces such as paved roadways, paved parking lots, treed parks, residential construction sites, open ploughed fields, and the river. Insolation of the ground is required for their formation, and neutral thermal stability aloft favours their incidence.