Ask a Question
Notify Me On Question Update
Email this Question
Would like to know how many drops in one ounce of water equals how many parts per million? Or quart ect.
Rate This FAQ
Parts Per Million (PPM)
A unit of concentration often used when measuring levels of pollutants in air, water, body fluids, etc. One ppm is 1 part in 1,000,000. The common unit mg/liter is equal to ppm. Four drops of ink in a 55-gallon barrel of water would produce an "ink concentration" of 1 ppm.
Parts Per Billion (PPB)
One part per billion is 1 part in 1,000,000,000. One drop of ink in one of the largest tanker trucks used to haul gasoline would represent 1 ppb.
The difference between 1 ppm and 1 ppb is important. A prestigious scientific journal recently reported the concentration of a substance as 0.5-1.5 ppm. The real value was 0.5-1.5 ppb. The difference between $1 and $1000!
Parts Per Trillion (PPT)
A unit of concentration used to measure vanishingly small levels of pollutants or contaminants in, for example, body fluids. One ppt is 1 part in 1,000,000,000,000. One drop of ink distributed through the water contained in a total of 4 of the 3-million-gallon reservoirs pictured would result in a final concentration of 1 ppt.
The remarkable advances in the sensitivity of modern analytical techniques makes it possible to detect some substances at the ppt level whose presence would not have been detected using earlier assay methods.
Submit Your Suggestion
Other Questions In This Topic
- What can you tell me about the new dietary guidelines?
- When the calories are listed on a food product, is that "as is" being unprepared or is that prepared? For example, bacon might list a 2 slice portion at 100 calories?
- How safe are home canned quick breads?
- Do you have tips on cooking for one?
- Do you have tips for dealing with lactose intolerance?
- Will you please send me a recipe for pesto?
- Do you have tips on food safety after a flood?
- My turkey brining recipe calls for 4 juniper berries crushed in the brine. Can I use the berries from my yard shrubs for this purpose?