Cell biology (formerly called cytology, from the Greek ÎºÏÏÎ¿Ï, kytos, vessel) is a branch of biology that studies the different structures and functions of the cell and focuses mainly on the idea of the cell as the basic unit of life.
(B) For a cylinder having a water capacity over 12 pounds-- (1) By hydrostatic test without determination of expansion (modified hydrostatic test method). A retest must be performed 12 years after the original test date and at 7-year intervals; or (2) By hydrostatic test using the water jacket method. A retest must be performed 12 years after the original test date and at 12-year intervals thereafter.
2 Procedures. Pressure tests are performed to ensure the safety, reliability, and leak tightness of pressure systems. A. pressure test is required for a new pressure system before use or an existing pressure system after repair or. alteration. There are two methods for pressure tests: hydrostatic and pneumatic. A hydrostatic test is performed by.