BS EN 13184:2001

Foreword
1 Scope
2 Normative references
3 Terms and definitions
4 Personnel qualification
5 General requirements
6 Calibration
7 Pressure decay technique - See EN 1779, technique D.1
8 Pressure rise technique - See EN 1779, technique D.2
9 Bell pressure change technique - See EN 1779, technique D.3
10 Flow measurement technique - See EN 1779, technique D.4
11 Test report
Annex A (normative) Calculations for pressure change
                      methods
Annex B (informative) Determination of the leakage rate
                      in the presence of outgassing and
                      permeation
Annex C (informative) Check for leakage across the
                      isolation valve

Describes techniques for determination of leakage rates across the boundary of an isolated object, subject to a pressure difference.

This document describes the techniques for the determination of the leakage rates across the boundary of an isolated object, subjected to a pressure difference. The techniques are based on the evaluation of the change of the mass of gas within the test object. The ideal gas equation states the relationship between mass, pressure, temperature, volume of the gas contained in the internal free volume of the object. In some circumstances one or more variables may be considered constant and so the mass change can, for example, be assessed by monitoring the pressure or pressure-temperature changes within the test object.

The volume change of the object (due to pressure and temperature changes during the test) should be taken into account. In most industrial applications, however, this change is so small that it can be neglected. Therefore the main part of this standard considers the volume as a constant during the test.

The deformability of the object under test is normally to be considered in drafting of the test specification and, if test precision can be affected by a volume change, alternative formulae or some techniques of keeping the pressure constant (flow measurement) can be used.