Leakage rate
Tightness and mechanics- Notion of tightness and associated measures

A leak is characterized quantitatively by the quantity of fluid escaping from containment. It is expressed as :

• or by the mass that circulates per unit of time, the legal unit being the kilogramme per second (kg.s ^-1 ); in practice, as this unit is often too large, sub-multiples such as the gramme per second (g.s ^-1 ) or per hour (g.h ^-1 ) are most often used;

• or by the volume escaping per unit time, expressed in cubic meters per second (m ³ .s ^-1 ); here too, sub-multiples such as cubic centimeters per second (cm ³ .s ^...