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Children are considered to be a vulnerable population when it comes to exposures to hazardous substances. Schools, where children spend about one third of their day, are expected to be a safe environment. Yet, there are many hazardous substances in schools that can be inadvertently or intentionally released and harm the health of students and teachers alike. The purpose of this analysis is to characterize acute chemical release incidents in school settings and identify prevention practices. The acute chemical incident surveillance programs of the Agency for Toxic Substances and Disease Registry (ATSDR) captured 24,748 acute chemical release incidents from 14 states that participated during 2008-2013. We examined 335 of these incidents that occurred at schools. While only 1.3% (n = 335) of all chemical incidents reported to ATSDR occurred in schools, these incidents represented a larger part of the total impacts, including 8.5% of incidents with persons injured, 5.7% of evacuations ordered, and 31.1% of people evacuated. Natural gas (21.8%) and mercury (18.2%) were the chemicals most frequently released. Collecting and analyzing data on acute school chemical releases allows stakeholders to target prevention initiatives and provide a school environment safe from these chemical exposures., Introduction According to the National Center for Education Statistics, approximately 54 million students attended 116,240 public and private elementary and secondary schools within the U.S. during the 2011-2012 school year [...]

Despite significant advances in risk management, the routing of hazardous materials (hazmat) has relied on relatively simplistic methods. In this paper, we apply an advanced risk measure, called conditional value-at-risk [...]

With the advent of the 2000 edition of National Fire Protection Association (NFPA) 70E, Standard for Electrical Safety Requirements for Employee Workplaces, comes a new language addressing the threat of arc flash. While this threat has been around for many years, it has received considerable attention in recent years due to the necessity of working on energized equipment and the subsequent accidents involving arc flash each year. Included in NFPA 70E-2004 are terms such as flash hazard, flash-protection boundary, and incident energy. This paper will describe the three methods for conducting an arc-flash hazard assessment contained in NFPA 70E-2004, as well as the IEEE Std 1584-2002 method of conducting an arc-flash hazard analysis. This paper will discuss the effectiveness and merit of each technique. In addition, a sample system will be analyzed and used to compare the results of each hazard-assessment method. Index Terms--Flash hazard analysis, flash-protection boundary, IEEE Std 1584-2002, incident energy, National Fire Protection Association (NFPA) 70E, personal protective equipment (PPE).

Examining the relationship between health outcomes and environmental exposures requires summary measures, or indicators. To advance the use of indicators, the Johns Hopkins Center for Excellence in Environmental Public Health Tracking piloted three pairs of indicators: 1) air toxics and leukemia in New Jersey, 2) mercury emissions and fish advisories in the United States, and 3) urban sprawl and obesity in New Jersey. These analyses illustrate the feasibility of creating environmental hazard, exposure, and health outcome indicators, examining their temporal and geographic trends, and identifying their temporal and geographic relationships. They also show the importance of including appropriate caveats with the findings. The authors' investigations demonstrate how existing environmental health data can be used to create meaningful indicator measures to further the understanding of environment-related diseases and to help prioritize and guide interventions. Indicators are the foundation of environmental public health tracking, and increased use and development of them are necessary for the establishment of a nationwide tracking network capable of linking environmental exposures and health outcomes., Introduction Effective environmental health tracking requires a coordinated approach that identifies hazards, evaluates exposures, and tracks population health (Litt, Tran, Malecki, Neff, Resnick, & Burke, 2000). According to the Environmental [...]

The uncertainties in simulations of annually averaged concentrations of two air toxics (benzene and 1,3-butadiene) are estimated for two widely used U.S. air quality models, the Industrial Source Complex Short-Term, version 3, (ISCST3) model and the American Meteorological Society-Environmental Protection Agency Model (AERMOD). The effects of uncertainties in emissions input, meteorological input, and dispersion model parameters are investigated using Monte Carlo probabilistic uncertainty methods, which involve simultaneous random and independent perturbations of all inputs. The focus is on a 15 km x 15 km domain in the Houston, Texas, ship channel area. Concentrations are calculated at hypothetical receptors located at the centroids of population census tracts. The model outputs that are analyzed are the maximum annually averaged maximum concentration at any single census tract or monitor as well as the annually averaged concentration averaged over the census tracts. The input emissions uncertainties are estimated to be about a factor of 3 (i.e., covering the 95% range) for each of several major categories. The uncertainties in meteorological inputs (such as wind speed) and dispersion model parameters (such as the vertical dispersion coefficient [[sigma].sub.z] also are estimated. The results show that the 95% range in predicted annually averaged concentrations is about a factor of 2-3 for the air toxics, with little variation by model. The input variables whose variations have the strongest effect on the predicted concentrations are on-road mobile sources and some industrial sources (dependent on chemical), as well as wind speed, surface roughness, and [[sigma].sub.z]. In most scenarios, the uncertainties of the emissions input group contribute more to the total uncertainty than do the uncertainties of the meteorological/dispersion input group.

Byline: Melvin R. Willis, Arturo A. Keller Keywords: Air toxics; Risk assessment; Air pollution; City planning; Regional planning; Strategic environmental assessment Abstract: Our research focuses on the linkage between land use planning policy and the spatial pattern of exposure to air toxics emissions. Our objective is to develop a modeling framework for assessment of the community health risk implications of land use policy. The modeling framework is not intended to be a regulatory tool for small-scale land use decisions, but a long-range planning tool to assess the community health risk implications of alternative land use scenarios at a regional or subregional scale. This paper describes the development and application of an air toxic source model for generating aggregate emission factors for industrial and commercial zoning districts as a function of permitted uses. To address the uncertainty of estimating air toxics emission rates for planned general land use or zoning districts, the source model uses an emissions probability mass function that weights each incremental permitted land use activity by the likelihood of occurrence. We thus reduce the uncertainty involved in planning for development with no prior knowledge of the specific industries that may locate within the land use district. These air toxics emission factors can then be used to estimate pollutant atmospheric mass flux from land use zoning districts, which can then be input to air dispersion and human health risk assessment models to simulate the spatial pattern of air toxics exposure risk. The model database was constructed using the California Air Toxics Inventory, 1997 US Economic Census, and land assessment records from several California counties. The database contains information on more than 200 air toxics at the 2-digit Standard Industrial Classification (SIC) level. We present a case study to illustrate application of the model. LUAIRTOX, the interactive spreadsheet model that applies our methodology to the California data, is available at http://www2.bren.ucsb.edu/~mwillis/LUAIRTOX.htm. Author Affiliation: Donald Bren School of Environmental Science and Management, University of California, Santa Barbara, CA 93106, USA Article History: Received 28 April 2005; Revised 21 January 2006; Accepted 15 March 2006

The authors analyzed a database of acute chemical releases to describe characteristics of chemicals that may be used as weapons of terrorism. Chemicals of primary concern (Priority I) on the Chemical Terrorism Listing of the Centers for Disease Control and Prevention were cross-referenced with data for 1993-2002 from the Hazardous Substances Emergency Events Surveillance (HSEES) system. HSEES captured 58,043 single-substance releases of 2,366 chemicals during this time period. The 48 Priority I chemicals accounted for 11,567 (20 percent) of the releases, while representing only 2.0 percent of reported chemicals. Events involving Priority I chemicals resulted in twice as many victims, more injured members of the general public, more victims treated at hospitals, a higher frequency of respiratory irritation, more evacuations, more people evacuated per event, and more decontaminations than did all other HSEES events. Industry, responders, and hospitals should consider the results of this analysis in preparing for and responding to acute chemical releases., Introduction In recent years, government agencies have devoted increasing attention to the possibility of chemical-terrorism events. The Agency for Toxic Substances and Disease Registry (ATSDR), an agency of the U.S. [...]