Petrol-driven vehicles

The first air-quality sensors for cars used a Japanese sensor element in which a sensitive tin-oxide material was layered onto a ceramic carrier. This sensor matches very well the requirements for a sensor for controlling air quality in petrol-driven vehicles. In 1986 the first generation was completed it used an Sn02 sensor and detected more than 85% of exhaust gases. However, diesel engines also produce nitrogen oxides, which can not be detected by tin-oxide sensors. 

Lead emissions from petrol driven vehicles (other products of combustion such as carbon monoxide are the major risk)... 

When considering the recharging of batteries for vehicles such as forklift trucks and other mechanical handling devices overcharging cut-out safety devices should be installed and maintained to prevent any potential for the release of hydrogen. Such operations will also require many of the aspects covered when refuelling petrol driven vehicles such as good ventilation. 

Potential sources of carbon monoxide hazards include metal-refining processes, in which it is formed as a byproduct and used as a fuel (LEL 12.5%), and running vehicle engines (particularly petrol-driven) or gas-fired heaters in poorly ventilated confined spaces. It is also a feedstock in the manufacture of a variety of chemicals, e.g. methanol, acetic acid, phosgene and oxo-alcohols. 

A petrol- or diesel-driven vehicle or a trailer towed by a petrol- or diesel-driven vehicle is used. It is better to use either battery-operated trucks or diesel engine vehicles in an enclosed explosive area. If a petrol engine vehicle is used, it must be parked outside the traverse of an explosive building or at least 5 m away from an untraversed building. 

The contribution of the various types of motor vehicles to the total line traffic-generated particulate matter was not quantified in this study. The traffic composition analysis indicated that petrol-driven passenger cars fitted with catalytic converters were the major contributor to traffic counts (about 60%). The daily traffic count ranged from 14,000 to 17,000 vehicles/h (15,500 1,200 vehicles/h). Results showed that traffic pattern on all days of a week had similar trend. Traffic count started to rise between 0700 and 1,300 h (mean 15,000 vehicles/h), before reaching maximum traffic count during 1,300-1,700 h (15,000-17,000 vehicles/h). Traffic counts then decreased between 1,700 and 2,000 h due to the diversion of vehicles towards other alternative routes as the Electronic Road Pricing (ERP)... 

Electrically-powered (lead-acid) battery driven vehicles have been used for many years in a range of applications. They have found widespread and growing employment in support services at airports and in industry, as tractors and forklift trucks, and for recreational use, for instance as golf trollies. In these off-road applications they are preferred to petrol or diesel-powered vehicles because they are cleaner, quieter and more economical. 

The Renault Scenic fuel cell vehicle (see the listed web site) has a specially developed high-efficiency squirrel cage induction motor for each road wheel, and is likely to have rivals in competing projects. However, at http //www.sustainability. renault.com/html/image.htm img=images/p/p.jpg, Renault shows a car layout with a front axle driven by one motor. There is a 48 VDC to DC converter followed by a DC to AC inverter. The hydrogen source is a petrol reformer. Evidently the project is still fluid. Setting out the options and alternatives is in hand. 

Environmental airborne hazards in the form of pollution can be produced from petrol or diesel engine powered vehicles or machinery. This is a particular problem when the engines are poorly maintained or being overworked. Carbon monoxide from petrol or diesel driven plarrt is a serious health problem when operated in enclosed areas. 

Long-term factors which will increase the electronic content of cars include the arrival of fuel-cell powered cars and the further development of hybrid vehicles where the petrol engine is used to generate electricity using an alternator and the wheels are driven by electric motors, power being stored in... 

An intermediate step in the search for an acceptable battery-powered car may be some form of hybrid vehicle, which uses an auxiliary power source (e.g. a petrol or diesel engine, or perhaps even a small fuel cell) as well the battery-driven electric motor. Several prototypes are currently under development. The auxiliary engine extends the range achievable and can be used to recharge the battery whilst in motion. Aithough these are iow rather than zero-emission vehicles, they may be an acceptable short-run compromise, especially if the auxiliary motor is restricted to non-urban use. 

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