DEVELOPMENT OF A PERFORMANCE-BASED HIGHWAY DESIGN PROCESS: Incorporating Safety Considertation into Highway Design

For nearly 100 years the design of highways has incorporated safety through the application of criteria to each individual design element. Design elements are items like the horizontal curve, vertical curves, the cross-section, clear zone and roadside slopes. As a result, safety is only indirectly addressed since the design elements are developed in isolation without a good understanding on the impact of one element on another. To make matters worse, design elements communicate messages to the driver about the appropriate speed for the highway. Long straight tangent sections encourage drivers to drive faster whereas curved highway segments communicate a lower operating speed. This can lead to inconsistent message to the driver when design elements are not coordinated with each other. A new method is proposed that accounts for the interaction between design elements in such a way that the designer can estimate the frequency and societal cost of motor vehicle crashes. With this estimate of cost, the designer can base design decisions on what would minimize the societal cost of both the infrastructure improvement and safety. This method will allow designers to formulate highway designs that achieve a specific level of safety and communicate consistent information to drivers. This research provides a valuable planning and design tool for practitioners and policy makers alike. It represents an important shift in the highway design paradigm

The Melbourne epidemic thunderstorm asthma event 2016: an investigation of environmental triggers, effect on health services, and patient risk factors

Background: A multidisciplinary collaboration investigated the world's largest, most catastrophic epidemic thunderstorm asthma event that took place in Melbourne, Australia, on Nov 21, 2016, to inform mechanisms and preventive strategies. Methods: Meteorological and airborne pollen data, satellite-derived vegetation index, ambulance callouts, emergency department presentations, and data on hospital admissions for Nov 21, 2016, as well as leading up to and following the event were collected between Nov 21, 2016, and March 31, 2017, and analysed. We contacted patients who presented during the epidemic thunderstorm asthma event at eight metropolitan health services (each including up to three hospitals) via telephone questionnaire to determine patient characteristics, and investigated outcomes of intensive care unit (ICU) admissions. Findings: Grass pollen concentrations on Nov 21, 2016, were extremely high (>100 grains/m3). At 1800 AEDT, a gust front crossed Melbourne, plunging temperatures 10°C, raising humidity above 70%, and concentrating particulate matter. Within 30 h, there were 3365 (672%) excess respiratory-related presentations to emergency departments, and 476 (992%) excess asthma-related admissions to hospital, especially individuals of Indian or Sri Lankan birth (10% vs 1%, p<0·0001) and south-east Asian birth (8% vs 1%, p<0·0001) compared with previous 3 years. Questionnaire data from 1435 (64%) of 2248 emergency department presentations showed a mean age of 32·0 years (SD 18·6), 56% of whom were male. Only 28% had current doctor-diagnosed asthma. 39% of the presentations were of Asian or Indian ethnicity (25% of the Melbourne population were of this ethnicity according to the 2016 census, relative risk [RR] 1·93, 95% CI 1·74–2·15, p <0·0001). Of ten individuals who died, six were Asian or Indian (RR 4·54, 95% CI 1·28–16·09; p=0·01). 35 individuals were admitted to an intensive care unit, all had asthma, 12 took inhaled preventers, and five died. Interpretation: Convergent environmental factors triggered a thunderstorm asthma epidemic of unprecedented magnitude, tempo, and geographical range and severity on Nov 21, 2016, creating a new benchmark for emergency and health service escalation. Asian or Indian ethnicity and current doctor-diagnosed asthma portended life-threatening exacerbations such as those requiring admission to an ICU. Overall, the findings provide important public health lessons applicable to future event forecasting, health care response coordination, protection of at-risk populations, and medical management of epidemic thunderstorm asthma. Funding: None