the physical properties of leak testing. Description: To test for leaks a pressure bubble test is performed. This is adding a specified pressure and submerging the test object under water to see if air leaks emerge. The requirement is that no leaks shall be detected when a certain pressure 1 is applied during a predefined time 1.
 I’m currently looking for a way to speed up this process.  When decreasing the time, pressure should logically increase to draw the same conclusions. However what I would like to know is if there is more know about this relationship or/and if it is possible to superimpose this if this relationships is too complicated. 
 A: I am afraid my answer will have little to do with physics. 
I don't know why you want to "speed up the process", but, unless you are developing a new building code, specification, or something like that (and I guess you would not need to ask anything here if it were so), please just don't even try to do that.
Pressure tests are typically done using water, as water has low compressibility, so it's more safe than, say, pneumatic pressure testing, but there are still all kinds of hazards. For example, when the company I worked for designed and supervised erection of a new steam pipeline, we just could not perform hydrostatic testing as the supports were designed to withstand the weight of pipes filled with steam, not with water, and the pipeline was at a height of about 5 m. Prior to that I took part (mine was a modest role) in hydrostatic pressure testing of a new pipeline at another thermal power station. During the testing, the maximum pressure happened to be much higher (400 bar) than the design test pressure (250 bar), as the pump controls were not adequate. Thank god, the pipeline withstood that pressure. The foreman of local erectors said: "Another pressure test has passed, and I am still out of prison:-)" So the tests are not totally safe, but negligence during tests can also cause problems during operation, when there can be something much less innocent in the system than cold water: it can be steam, flammable or poisonous fluids, you name it. A leak during operation can cost and sometimes costs dearly. For example, it seems that a misinterpreted pressure test was one of the major causes of the catastrophe in the Gulf (http://www.nola.com/news/gulf-oil-spill/index.ssf/2010/11/oil_spill_commission_bps_final.html ).
So maybe you should not play with pressure tests and should just do exactly what codes or specifications require.    
