What is a part per billion?

Substances found at very low levels in water are often measured at the level of parts per billion (ppb). A part per billion is the same as one microgram per liter (ug/L). One part per billion is equivalent to one second in 32 years or a single penny in ten million dollars.

Show All Answers

1. Is my drinking water safe?
2. Is this substance in my water?
3. What is a part per billion?
4. How did the District find out that 1,4-dioxane was in the District’s groundwater sources?
5. What is 1,4-dioxane?
6. What level of 1,4-dioxane is considered safe in drinking water?
7. What is the District doing now that it knows this substance is present in the water?
8. Does the District know the source of 1,4-dioxane?
9. How are the State and EPA working to address the source of 1,4-Dioxane in the District's drinking water supply?
10. How will the District keep customers informed about the occurrences of 1,4-Dioxane?
11. How can I contact the District to get more information on this topic?