Do not stock up on unnecessary solvents and clean the house regularly to prevent biological and chemical contaminants from building up.

These requirements are designed to prevent contaminants from moving into drinking water sources.

This is a pure clay used to seal wells and other soil borings to prevent contaminants from getting in the hole.

Grease and air purge fittings are often provided to prevent contaminants from entering the packing seals.

The boxes had sliding bands to open or close gaps to allow steam or prevent contaminants from entering the box.

The state requires that oil companies seal a well with cement plugs once production has stopped in order to prevent contaminants from escaping.

A third O ring has been added as a "wiper seal" to prevent contaminants from getting into the joint during assembly.

"These also help to prevent contaminants from getting into our samples."

Unlike many New York City treatment plants, those plants do prevent raw sewage and contaminants from entering the water.

The film of flowing water would theoretically prevent contaminants from settling into cracks and crevices.