A measure of the resistance of a fluid to flow. For liquids, viscosity increases with decreasing temperature. For gases, viscosity increases with increasing temperature. Expressed as mass per length-time (e.g. kilograms per meter-second). A common viscosity unit is the Poise. One poise equals 1.0 gram per centimetersecond. Also referred to as Dynamic Viscosity.
Go to Process Safety Glossary