Douglas S. Thomas

Investigation of the decline in reported smoking-caused wildfires in the USA from 2000 to 2011

The number of smoking-caused wildfires has been falling nationwide. In national forests in 2011, smoking-caused wildfires represented only 10% of their 1980 level. No other cause of wildfire has experienced this level of decline. For 12 states, we evaluate the rate of smoking-caused wildfires and find it is a function of weather, other ignitions, the number of adult smokers, the presence of improved wildfire cause-determination methods, and whether a state required the sale of less fire-prone cigarettes. We find the decline in adult smoking rates has led to a reduction of smoking-caused fires by 9%. The finding that less fire-prone cigarettes appear successful at limiting wildfire starts – by 23% – is a likely unintended benefit of a technology aimed at reducing fire fatalities in residences. We also find that the improvements in wildfire cause determination have resulted in a reduction in smoking-classified fires by 48%. Although improved wildfire cause-determination methods do not necessarily reduce the number of wildfires, they ensure that the causes of wildfire are accurately tracked. Accurate wildfire cause determination can, however, result in targeting wildfire-prevention programs to specific fire-cause categories, which can lead to a reduction in the overall number of wildfires.

Identifying high resource consumption areas of assembly-centric manufacturing in the United States

This paper examines supply chain value added in the US for producing assembly-centric products, which includes machinery, computers, electronics, and transportation equipment, and determines whether costs are disproportionally distributed. The implication being that reductions in resource consumption in some cost areas can disproportionally reduce total resource consumption. Efforts to develop and disseminate innovative solutions to improve efficiency can, therefore, be targeted to these high cost areas, resulting in larger efficiency improvements than might otherwise be achieved. An input–output model is used for this examination and is combined with labor data and data on assets. The top 20 industries, occupations, and industry occupation combinations contributing to production are identified. A sensitivity analysis is conducted on the model using Monte Carlo simulation. The results confirm that costs are disproportionally distributed, having a Gini coefficient of 0.75 for value added and for compensation it is 0.86. Wholesale trade, aircraft manufacturing, and the management of companies and enterprises were the industries with the largest contribution to assembly-centric manufacturing, even when including imports. Energy in the form of electricity and natural gas were discussed separately, but would rank 8th if compared to the industry rankings. In terms of occupation activities, team assemblers, general and operations managers, and sales representatives were the largest occupations. Public entities might use this model and results to identify efficiency improvement efforts that will have the largest impact on industry per dollar of expenditure.

The net benefits of human-ignited wildfire forecasting: the case of tribal land units in the United States

Research shows that some categories of human-ignited wildfires might be forecastable, due to their temporal clustering, with the possibility that resources could be pre-deployed to help reduce the incidence of such wildfires. We estimated several kinds of incendiary and other human-ignited wildfire forecast models at the weekly time step for tribal land units in the United States, evaluating their forecast skill out of sample. Analyses show that an Autoregressive Conditional Poisson (ACP) model of both incendiary and non-incendiary human-ignited wildfires is more accurate out of sample compared to alternatives, and the simplest of the ACP models performed the best. Additionally, an ensemble of these and simpler, less analytically intensive approaches performed even better. Wildfire hotspot forecast models using all model types were evaluated in a simulation mode to assess the net benefits of forecasts in the context of law enforcement resource reallocations. Our analyses show that such hotspot tools could yield large positive net benefits for the tribes in terms of suppression expenditures averted for incendiary wildfires but that the hotspot tools were less likely to be beneficial for addressing outbreaks of non-incendiary human-ignited wildfires.

An examination of national supply-chain flow time

ABSTRACT The US and other national governments invest in research and development to spur competitiveness in their domestic manufacturing industries. However, there are limited studies on identifying the research efforts that will have the largest possible return on investment, resulting in suboptimal returns. Manufacturers commonly measure production time in order to identify areas for efficiency improvement, but this is typically not applied at the national level where efficiency issues may cross between enterprises and industries. Such methods and results can be used to prioritize efficiency improvement efforts at an industry supply-chain level. This paper utilizes data on manufacturing inventory along with data on inter-industry interactions to develop a method for tracking industry-level flow time and identifying bottlenecks in US manufacturing. As a proof of concept, this method is applied to the production of three commodities: aircraft, automobiles/trucks, and computers. The robustness of bottleneck identification is tested utilizing Monte Carlo techniques.

Underreporting of wildland fires in the US Fire Reporting System NFIRS: California

The absence of a comprehensive and accurate database on fire occurrence means that some proportion of wildfires is not reported. This paper examines wildfires reported in the National Fire Incident Reporting System (NFIRS) database and compares it with the satellite-based Moderate Resolution Imaging Spectroradiometer (MODIS) fire detection data and the CAL FIRE Fire and Resource Assessment Program (FRAP) geodatabase to understand underreporting of wildland fires in the NFIRS system. The paper discusses a series of large wildland fires and uses a Generalised Linear Model to identify the conditions where large wildfires go unreported. This paper shows that the NFIRS database, which is the primary fire database in the US, significantly underreports wildland fires. Evidence from California suggests that 32% of fires within local jurisdictions detected via MODIS satellite were identified in the NFIRS database; thus, there could be a significant number of fires going unreported nationwide. Examining eight large fires in California, only 16% of the structures damaged or destroyed, as reported in CAL FIRE, were reported in NFIRS. Areas with underreporting tend to have a higher level of poverty, higher population density, higher level of people without vehicles, lower income and a higher level of single parents with children under 18, as well as a higher level of people under the age of 18.

Cigarette Fires Involving Upholstered Furniture in Residences: The Role that Smokers, Smoker Behavior, and Fire Standard Compliant Cigarettes Play

Residential structure fires pose a significant risk to life and property. A major source of these fires is the ignition of upholstered furniture by cigarettes. It has long been established that cigarettes and other lighted tobacco products could ignite upholstered furniture and were a leading cause of fire deaths in residences. In recent years, states have adopted fire standard compliant cigarettes (‘FSC cigarettes’) that are made with a wrapping paper that contains regularly spaced bands, which increases the likelihood of self-extinguishment. This paper measures the effectiveness of FSC cigarettes on the number of residential fires involving upholstered furniture, and the resulting fatalities, injuries, and extent of flame spread, while accounting for the under-reporting of fire incidents. In total, four models were estimated using fire department data from 2002 to 2011. The results provide evidence that FSC cigarettes, on average, reduced the number of residential fires by 45%, reduced fatalities by 23%, and extent of flame spread by 27% in 2011. No effect on injuries was found. Within each state, effectiveness is moderated by the number of smokers and their consumption patterns. In general, FSC cigarettes are more effective in places with a large smoking population who engage in heavier smoking. There is a very limited effect on the lightest of smokers, suggesting behavioral differences between heavy and light smokers that influence fire risk.

An Economics-Based Intelligence (EI) Tool for Pressure Vessel and Piping (PVP) Failure Consequence Estimation

This paper is built around ASTM E 2506, Standard Guide for Developing a Cost-Effective Risk Mitigation Plan for New and Existing Constructed Facilities. E 2506 establishes a three-step protocol—perform risk assessment, specify combinations of risk mitigation strategies for evaluation, and perform economic evaluation—to insure that the decision maker is provided the requisite information to choose the most cost effective combination of risk mitigation strategies. Because decisions associated with low-probability, high-consequence events involve uncertainty both in terms of appropriate evaluation procedures and event-related measures of likelihood and consequence, NIST developed a Risk Mitigation Toolkit. This paper uses (a) a data center undergoing renovation for improved security, and (b) a PVP-related failure event to illustrate how to perform the E 2506 three-step protocol with particular emphasis on the third step—perform economic evaluation. The third step is built around the Cost-Effectiveness Tool for Capital Asset Protection (CET), which was developed by NIST. Version 4.0 of CET is used to analyze the security- or failure-related event with a focus on consequence estimation and consequence assessment via Monte Carlo techniques. CET 4.0 includes detailed analysis and reporting features designed to identify key cost drivers, measure their impacts, and deliver estimated consequence parameters with uncertainty bounds. Significance of this economics-based intelligence (EI) tool is presented and discussed for security- or failure-consequence estimation to risk assessment of failure of critical structures or components.