Diesel Exhaust Fluid (DEF) is a non-toxic, high purity solution comprised of 32.5% urea and 67.5% de-ionized water.

Is DEF non hazardous?

DEF in non-toxic, non-flammable and is not dangerous. It is actually less hazardous than other fluids such as antifreeze, engine oil or diesel. … Your DEF dealer can advise you and ISO 22241 standards should be used when materials come in contact with DEF.

Can you dump DEF down the drain?

If one needs to dispose of bad DEF, do so in an ethical manner. Do not pour DEF down a drain or dump outside. Every area has proper DEF disposal regulations so check with the local government, municipal and environmental agency.