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Safer cities

Threats to human safety and security in cities come in many forms – be they accidents, catastrophic events, intentional acts or natural disasters. These can be tackled with risk assessment, urban planning, and early warning systems, utilising technologies for weather forecast, climate-adaptation and hazard mapping, as well as security-focused law-enforcement tools – creating safer, more resilient urban spaces for all.

Everyone has a right to security and safety. In cities, urban security usually refers to preventing deliberate acts of harm or criminal behaviour, whereas urban safety often refers to preventing an unexpected event, such as an accident or natural disaster.

Risk management is hugely important in ensuring the safety and security of cities, and there are very particular approaches for specific types of hazards. Here, we focus on weather-related disasters (which are further aggravated by climate change), and road traffic accidents – which take the lives of millions every year.

Extreme weather events associated with climate change have a significant impact on urban centres. It is estimated that the number of storms, droughts, and floods have increased threefold in the last 30 years – disproportionately affecting developing countries. As a consequence, the number of people affected has risen dramatically: a total of 4.4 billion people (or 63% of the global population) have been, directly or indirectly, affected by disasters, with 1.3 million being killed between 1992 and 2012. Nearly 70% of all disaster-related deaths happened among those in lower income bands. Climate change also has an impact on migration patterns. Extreme weather events displaced four times more people (20 million) than conflict and violence in 2008, with some evidence that this is increasing urbanisation and hence boosting the populations of cities.

Urban poverty (which itself may be a driver for crime or civil unrest) is a further risk factor, due to its usual co-occurrence with poor disaster risk governance and limited access to early warning technologies. Remote sensing, Global Positioning System (GPS) and Geographic Information System (GIS) are therefore very important tools in disaster management, as they can help locate and map the affected areas, supporting rescue teams and assessing the level of damage.

Road accidents are another serious urban safety concern, with traffic injury and death increasing by the day in some countries. India ranks as the country with most road deaths, accounting for 10% of all global fatalities, despite having just 1% of the world’s vehicles. In the United States, there are 1.6 deaths per 10,000 vehicles, while in India the road fatality rate is 14 per 10,000, and, in China, 5. In Europe, over 25,000 people died in road accidents in 2016 – a decrease of 57% in the last 20 years. Still, 3,400 people die every day all over the world, while millions are injured and disabled every year.

Risk factors that can increase the likelihood of an injury or death include speeding, driving under the influence of an impairing substance, non-use of helmets and seat belts, distracting driving, unsafe road infrastructure, unsafe vehicles, inadequate post-crash care, and inadequate enforcement of traffic laws. 98% of countries (176) have a national drink-driving law in place with this being more likely among high income countries. Globally, South Africa has the highest rate of fatalities attributable to drink driving, with 58% of fatalities due to alcohol consumption and yet only 53 countries test all drivers who die in a crash for alcohol. Breath testing devices are important technologies used in crash prevention to estimate the level of alcohol in the blood which is most commonly used by police traffic officers to enforce road safety laws; 121 countries use random breath testing at checkpoints at specific times.

Tech solutions for safer cities

Urban safety, security and resilience can be improved by tackling social and economic factors such as exclusion, poverty, and inequality, as well as improving responsive urban planning and risk management procedures. Potential hazards can also be tackled by the use of technology – much of which is reliant on minerals and metals.

  • Global Positioning System

    Global Positioning System (GPS) is a satellite-based radio navigation service, delivering location and time information to terrestrial receivers. Geographic Information System (GIS) is the software that enables the access and use of the information collected by the GPS satellites. GPS and GIS technologies have a wide range of applications, enabling search and rescue teams to create maps of disaster areas for rescue and aid operations, as well as to assess damage. GPS is also used to enhance scientists’ capability for flood prediction and monitoring of seismic events. Due to its lightweight properties, aluminium is widely used in the structure of satellites, usually alloyed with other metals for strength, like beryllium. Carbon fibre, titanium, and nickel-cadmium alloy can also be used. Nickel, manganese, lithium, indium, and others are used in the solar panels that power the satellite and in the storage battery. Silicon is essential in the electronics used by the satellite to receive and send back signals from Earth.

  • Smartphones

    GPS is also being used to empower individuals in emergency planning for natural disasters utilising the technology in their mobile phones. For example, GPS technology is being used creatively in disaster risk reduction in the favelas (slums) of Rio de Janeiro, Brazil. A collaborative initiative by UNICEF and MIT (Massachusetts Institute of Technology) encourages the use of GPS-enabled smartphones to map local risks and vulnerabilities. The project trained over 100 young people from five low-income communities to perform hazard mapping using smartphones attached to kites to gather aerial images. The pictures help to identify the presence or absence of drainage systems, the availability of sanitation facilities, impediments to evacuation, and other issues. A mapping platform that enables real-time data collection was then developed to increase risk prediction against floods and landslides. This is just one example of the many innovative applications of smartphones, which contain several metals including copper, gold, silver, and lithium.

  • Breath alcohol testers

    Breath alcohol testers are used by the traffic police to determine the level of alcohol in the system of a suspected drink-driver. The most commonly-used test type is fuel cell, which functions by chemical reactions, with any alcohol present producing energy in the fuel cell. Fuel cell tests usually comprise a cell, pump, mouthpiece, printed circuit board, and LCD display. The case that contains the components is usually made of polystyrene plastic. The LCD display contains indium, silicon, tin, among others The fuel cell is composed of two platinum coated electrodes and a permeable electrolyte material, which are usually made of copper, titanium, brass, silver, and platinum. The printed circuit board controls the unit and the microprocessor contains the coding to carry the functions. These may contain gold, silver, copper, aluminium, tin, zinc, and many more.