R.G. Whitfield

Protective measures and vulnerability indices for the Enhanced Critical Infrastructure Protection Programme

Argonne National Laboratory in partnership with the US Department of Homeland Security (DHS) has developed a methodology to systematically evaluate the protection posture and vulnerability of critical infrastructure and key resources (CIKR). This vulnerability methodology is part of a larger effort by DHS called the Enhanced Critical Infrastructure Protection Programme, which seeks to mitigate vulnerabilities, enhance relationships, and improve information sharing between public and private entities. This methodology was constructed to be used in all CIKR sectors and to provide useful results to owners and operators of US facilities. The vulnerability index is also being used to assist DHS in analysing sector and subsector vulnerabilities, to identify potential ways to reduce vulnerabilities, and to assist in preparing sector risk estimates. The owner/operator also receives an analysis of the data collected for a specific asset, which gives an indication of the assets strengths and weaknesses with regard to security.

Allocating Vendor Risks in the Hanford Waste Cleanup

Organizations may view outsourcing as a way to manage risk. We developed a decision-analytic approach to determine which risks the buyer can share or shift to vendors and which ones it should bear. We found that allocating risks incorrectly could increase costs dramatically. Between 1995 and 1998, we used this approach to develop the request for proposals (RFP) for the US Department of Energys (DOEs) privatization initiative for the Hanford tank waste remediation system (TWRS). In the model, we used an assessment protocol to predict how vendors would react to proposed risk allocations in terms of their actions and their pricing. We considered the impact of allocating each major risk to potential vendors, to the DOE, or to both and identified the risk allocation that would minimize the DOEs total cost--its direct payments to vendors plus the costs of any residual risks it accepted. Allocating inappropriate risks to the vendor would have increased costs because the vendor would add a large risk premium to its bids, while allocating inappropriate risks to the DOE also would have increased costs because the vendor would not take adequate risk-reduction measures. With the improved risk allocation, the RFPs resulted in bids that were acceptable to the DOE.

A Health Risk Assessment for Use in Setting the U.S. Primary Ozone Standard

Abstract This paper describes the results of a U.S. assessment of the ozone-Induced acute pulmonary health risks associated with attainment of three alternative 1-hour average ozone standards: 0.12 ppm (current U.S. standard), 0.10 ppm, and 0.08 ppm. Risk results are presented for pulmonary function and respiratory symptoms 1n heavy exercisers, the group thought to be at highest risk to acute ozone exposure. To examine two alternative definitions of response adversity, ozone-Induced pulmonary function change 1s measured as FEV1 decrements of ≥10 and ≥20 percent; respiratory symptoms are characterized by cough, chest discomfort, or lower respiratory symptoms as a group, at two different severity levels–any (Including mild) and moderate/severe. Risk estimates are presented for up to ten U.S. cities: Chicago, Denver, Houston, Los Angeles, Miami, New York, Philadelphia, St. Louis, Tacoma, and Washington, D.C.

Overview of ozone human exposure and health risk analyses used in the U.S. EPA's review of the ozone air quality standard.

Abstract This paper presents an overview of the ozone human exposure and health risk analyses developed under sponsorship of the U.S. Environmental Protection Agency (EPA). These analyses are being used in the current review of the national ambient air quality standards (NAAQS) for ozone. The analyses consist of three principal steps: (1) estimating short-term ozone exposure for particular populations (exposure model); (2) estimating population response to exposures or concentrations (exposure-response or concentration-response models); and (3) integrating concentrations or exposure with concentration-response or exposure-response models to produce overall risk estimates (risk model). The exposure model, called the probabilistic NAAQS exposure model for ozone (pNEM/O 3 ), incorporates the following factors: hourly ambient ozone concentrations; spatial distribution of concentrations; ventilation state of individuals at time of exposure; and movement of people through various microenvironments (e.g., outdoors, indoors, inside a vehicle) of varying air quality. Exposure estimates are represented by probability distributions. Exposure-response relationships have been developed for several respiratory symptom and lung function health effects, based on the results of controlled human exposure studies. These relationships also are probabilistic and reflect uncertainties associated with sample size and variability of response among subjects. The analyses also provide estimates of excess hospital admissions in the New York City area based on results from an epidemiology study. Overall risk results for selected health endpoints and recently analyzed air quality scenarios associated with alternative 8-hour NAAQS and the current 1-hour standard for outdoor children are used to illustrate application of the methodology.

Acute Ozone Exposure-Response Relationships for Use in Health Risk Assessment

The U.S. Clean Air Act requires that primary national ambient air quality standards (NAAQS) be set to protect the public health, with an adequate margin of safety. As one input to its current review of the NAAQS for ozone, the U.S. Environmental Protection Agency (EPA) has sponsored an ozone health risk assessment. The first part of the assessment is directed at the effects of acute (1–2 hour) ozone exposure and estimates the risk of acute ozone-induced lung function impairment and lower respiratory symptoms in heavy exercisers, the group thought to be at highest risk from acute ozone exposure due to high dosage rates. Latter parts of the risk assessment, aimed at the effects of multihour and chronic ozone exposure, are underway. This paper describes development of the exposure-response relationships used in the acute effects part of EPA’s ozone health risk assessment. Relationships are derived from human clinical exposure studies in which heavily exercising subjects were exposed to ozone under controlled conditions. Data set comparisons are presented, along with a description of final exposure-response relationships and their derivation.