The following information on exhaust fumes and carbon monoxide is provided as colder weather approaches and we keep our car/van windows rolled up more. Carbon Monoxide is often called the silent killer because it is undetectable to our senses.
The exhaust of a poorly maintained vehicle can contain carbon monoxide concentrations of up to 10 per cent. Carbon monoxide (CO) is a poisonous gas, potentially lethal even in low concentrations and is undetectable to the senses.
Although the CO concentrations in the exhaust of a modern, emission controlled vehicle will be very low, even at concentrations of less than 0.1 per cent, lethal saturation of the blood can occur in just a few hours.
In a vehicle with missing or defective door, boot or tailgate seals, exhaust can enter the passenger compartment where carbon monoxide can build up in dangerous concentrations and poison those inside. Station wagons, hatchbacks and vans are especially prone to inwards exhaust leakage, but saloon cars aren't immune either.
Any exhaust odour noticed while driving should be regarded as life-threatening, especially if a long drive is planned.
Regular vehicle maintenance and inspection of the exhaust system is vital to protect you and others from the dangers of carbon monoxide. A visual inspection will turn up any defective or missing seals along the lower edges and up the lower sides of tailgates, rear doors and boot lids. Any unsealed openings in these areas should be treated as serious defects.
It is also important to check for exhaust leaks regularly, looking for holes in mufflers or pipes, and checking exhaust pressure by placing a protected hand over the end of the tailpipe. Use a rag on your hand and plug the end of the exhaust pipe with the engine running - the pressure should build up and blow your hand away from the pipe. If you can keep your hand there without much trouble, there is a leak in the exhaust system