Campaign against speed bumps

What they don't want you to know about 'speed humps'

Speed humps are fundamentally ineffective.

• Depending upon the vehicle and the hump design, going over a hump at a higher speed may cause less discomfort than a lower speed.

• Research carried out in Austria on a mile long stretch of road with six humps and a 40kph speed limit showed that cars negotiating the humps emmitted 10 times more nitrogen oxide, 3 times more poisonous carbon monoxide, and 25% more carbon dioxide, than vehicles maintaining a constant speed. Fuel consumption rose from 7.9 litres to nearly 10 litres per 100 km. The report concluded: "A regular traffic flow would therefore always be more environmentally friendly".

• The Transport Research Laboratory in the United Kingdom conducted emissions tests on roads with a 75 metre hump spacing and found CO emissions increased by 70–80%, Hydro-carbons by 70–100%, and CO2 by 50–60%.

• Braking may generate noise, especially with larger vehicles.

• Vehicles accelerating after a hump generate significantly more noise than had they been travelling at a constant speed.

• Repeatedly traversing humps causes long-term damage to vehicle components, especially the suspension. This in turn has serious implications for safety and stopping distances. Shock absorbers are key in ensuring vehicles are able to stop effectively and safely - perhaps if a child ran in front of a car. Residents of areas plagued with speed humps find they have to replace their shock absorbers far more often. Humps can even cause immediate damage to the bodywork of large vehicles such as buses, to the underside of cars with low ground clearance, and wreck front number plates, spoilers and exhausts. Goods carried in vehicles can also be damaged.

• Speed humps are nothing more than inverted potholes. Whilst local councils readily admit that potholes are dangerous and cause damage to vehicles, they intentionally install speed humps which are just as dangerous, and then try to deny that they cause damage.

• A speed hump on Corporation Street in Birmingham had to be rebuilt after numerous double-decker buses suffered damage to their front bodywork.

• A Birmingham bus company threatened to withdraw services from two roads when the council tried to install large speed humps, because of damage caused to low floor buses elsewhere in the city. The council backed down and installed 'speed cushions' instead.

• Fire Engines fitted with a water tank containing up to 2,250 litres may suffer structural damage so great that it puts the appliance off the road, and results in a massive repair bill.

• It's not just drivers who face increased costs. In Hastings in November 2002, taxi fares were increased by 10p during the day and 20p at night to pay for the increased cost of maintenance due to damage caused by traversing speed humps up to 200 times per day.

• In 2004, the Metropolitan Police told the London Assembly 34 of its vehicles had been damaged by speed bumps in a three month period. A subsequent report issued by the London Assembly's transport committee stated that the cost of this damage was £7,500. BBC

• Drivers judging how to negotiate humps are distracted from watching out for more serious hazards — like children.

When the London Borough of Barnet removed its speed humps, accidents reduced by 14.9% during the first six months of 2005.

• Frequent exposure to humps can cause back pain.

• The National Osteoporosis Society has stated that sufferers are being put at risk by speed humps.