Benzene is an important chemical, but toxic in nature. It is primarily used as an intermediate to make other chemical products including plastics, rubbers, dyes, lubricants, glues, paints, detergents, drugs and pesticides. It is also present in vehicle emissions, cigarette smoke and gasoline.
According to the World Health Organisation, there is no safe exposure for airborne benzene but OSHA in the US has set the permissible long-term exposure limit to 1ppm per 8 hour day, 40 hours a week, and a short-term exposure limit of 5 ppm for 15 minutes.
We tested a new Airbon* box with fresh carbon against one that had been used for just over 4 months in a car.
In our test report, we found that a sample of 1 gram of activated carbon from the used box had adsorbed 978 ppm of benzene fumes as well as other VOCs (volatile organic compounds) not tested.
If we measure this against the OHSA exposure limit above, we can break it down as follows:
The box was used for 113 days and there are 50g of activated carbon per box. This breaks down to 433 ppm per day or 18 ppm per hour which is 4.5 ppm per 15minutes.
Now compare this to the maximum short-term exposure limit of 5 ppm and the long-term exposure limit of 1 ppm.
It is important to note that this test was simply based on the adsorption of benzene, external influences are not taken into consideration, as these factors aren't standard and can't be controlled. The following are just a few examples of what can impact the number of VOCs in your car:
• Air pollution • Temperature • Relative Humidity • City or countryside • Traffic conditions • Age and type of car • Fuel type
Testing notes: The product we tested had the following parameters: Used in India in rural and semi-urban locations during the summer months. Driver was a non-smoker, and the car was 3 years old.
Learn more about Airbon and Activated Charcoal
Benzene test report on a used Airbon box