Project: Effect of Car Weight Reduction and Downsizing on Safety

Reference: S310C/CA

Last update: 21/07/2004 10:18:45

Objectives

The project objectives are:

* to report on the likely effects of car weight and size reduction on road casualty levels in the UK for a range of scenarios covering varying rates and levels of weight reduction and downsizing, safety improvement and fleet size profile changes;
* for given overall fuel consumption benefits, to identify and compare the following (also in terms of feasibility and cost-benefit):
a) measures to manage or influence changes to the fleet profile and downsizing to minimise any associated disadvantages;
b) modifications to vehicles or safety standards which would make the individual vehicle types and the fleet overall more suitable for prospective downsizing; and
c) alternatives to weight and size reduction which could reduce fuel consumption without compromising safety.

Description

Vehicle manufacturers are constantly investigating ways to reduce vehicle mass and size to minimise fuel consumption and help comply with ever increasing regulation on pollutant emissions. While being welcomed by environmental interests, it was feared that such changes could be detrimental to vehicle crash performance and thereby increase casualty numbers and injury severity. This project investigated these concerns by analysing accident data to determine the influence of car mass on the number and severity of casualties and then used computer modelling to examine the significance of mass and stiffness on vehicle impact performance.

The analysis showed that if a uniform downsizing across-the-parc took place, there would be a slight reduction in the total number of casualties in car accidents. However, if it appears that a non-uniform downsizing would occur, further research would be needed to assess the effect on accident casualties.

Separate research is currently investigating compatibility of cars in accidents and it is hoped this will give a greater understanding of these issues.

Contractor(s)

TRL Limited
Crowthorne House, Nine Mile Ride, Wokingham, Berkshire, RG40 3GA
+44 (0)1344 773131

Contract details

Cost to the Department: £120,000.00

Actual start date: 31 July 1995

Actual completion date: 31 December 1999

Publication(s)

PR/SE/532/99. The Use of Simplified Generic Computer Models to Investigate the Safety Implications of a General Reduction in Vehicle Size
Author: TRL Ltd.
Publication date: 01/12/1999
Unpublished
Source: Contact steve.gillingham@dft.gsi.gov.uk

PR/SE/123/95. The Likely Effects of Downsizing on Casualties in Car Accidents
Author: TRL Ltd
Publication date: 01/03/1999
Unpublished
Source: Contact steve.gillingham@dft.gsi.gov.uk

Summary of results

  1. Vehicle manufacturers are constantly investigating ways to reduce vehicle mass and size to minimise fuel consumption and help comply with increasingly stringent regulation on pollutant emmissions. While giving environmental gains it was possible that such changes could be detrimental to vehicle crash performance and thereby increase the number of fatal and serious injuries. This project investigated these concerns by analysing accident data to determine the influence of car mass on the number and severity of casualties and then used computer modelling to examine the significance of mass and stiffness on vehicle impact performance.