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Novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is spreading rapidly all over the world with over 23 million infected near the end of August 2020. There are also asymptomatic patients (APs) who are difficult to identify, but they are infectious and believed to be one of the transmission sources. No specific medicine, no vaccine and even no reliable quick identification tests on SARS-CoV-2 are available yet. Workable safety management must be implemented to stop such global pandemic resulting from disease transmission, including those infected through APs. A two-stage containment scheme is proposed with quarantining people into units within blocks. The units inside a block is to be open after being closed for quarantine for an agreed period such as 14 days. The blocks would then be sealed for another period before opening. Argument of the proposal was supported by a simple mathematical approach with parameters deduced from observations on a cruise ship to estimate the infection constant. The proposed containment scheme is believed to be effective in controlling the spreading of SARS-CoV-2 and identifying APs by a more targeted screening test for the suspected group with a more acceptable environment at the second stage of containment. [ABSTRACT FROM AUTHOR]

High-speed rail systems are expanding everywhere for carrying thousands of passengers every day. Train cars in underground spaces travel under dense urban areas, tunnels in mountainous places and bridges across rivers. Design fire in burning a train car should be studied carefully for fire hazard assessment in those long underground or enclosed spaces. There are full-scale burning testing results on the main combustibles including seat, curtain and passenger luggage in some train cars. The heat release rate of a high-speed train car model CRH1 will be studied using such data together with a two-layer fire zone model, the Consolidated Model of Fire and Smoke Transport (CFAST). Simulation will be performed on the full-sized train car with the heat release rate of the seat measured by experiment. Two fire scenarios with ignition points located in the front and rear areas of the train compartment are considered. The results of the fire simulations show that the heat release rate can reach 43 MW. The value is similar to the full-scale burning experiments on train cars in Sweden and South Korea. Active fire protection systems have to be seriously considered in those underground or enclosed areas. [ABSTRACT FROM AUTHOR]

Electrical vehicles are planned to be the future green land traffic means in many places. However, reported vehicle fires or even explosions have raised public safety concern. Fire hazards studies of electric vehicles are commonly focused on ignition of genuine batteries. However, cheap counterfeit batteries of are widely used in electric vehicles in some countries. Counterfeit LIBs are made of unknown battery materials, electrolytes and construction with poor quality control. These counterfeit batteries are not designed for compatibility, not manufactured according to standards, and even not tested. Thus research results based on genuine batteries may not be applicable to counterfeit batteries. Batteries should be taken as a big ignition source for electric vehicles and fire hazards could occur during driving, charging or even when not in use. Further, very few works reported the effect of burning of the combustibles of car and smoke to the passengers trapped inside. Fire risk factors should be studied holistically for the entire vehicle to explore practical fire-safe engineering solutions. Key fire aspects of electric vehicles are pointed out in this paper to alert the society, particularly the authority and professionals handling fire safety. [ABSTRACT FROM AUTHOR]