Volcanic ash is a great nuisance and gets everywhere in the house and office, including inside televisions, computers, cameras and other valuable equipment, where it can cause irreparable damage. Ash is different from ordinary house dust. Its sharp, crystalline structure causes it to scratch and abrade surfaces when it is removed by wiping or brushing.
In wet weather ash deposits are dampened down and the air can be clear, but in drier weather ash can easily be stirred up and remobilized by wind and traffic. As a result suspended dust levels become much higher and can be at levels potentially harmful to health.
Rainfall and wind are effective in removing ash, and grass and other plants will eventually bind it to the soil. However, with large ashfalls this process is too slow and the ash must be cleaned up and taken away from populated areas. In addition, wind may also bring ash into areas that were previously clean so ash may be present in the environment for months or even years following an eruption.