49. What are the methods used to detect the tube leak with vacuum and with out vacuum?

Detection methods requiring vacuum include :

1. Foam
2. Halogen gas
3. Bubbler leak
4. Indiplugs
5. Acoustic meters
6. Conductivity measurements

Those that do not require vacuum includes :

1. Fluorescein
2. Bubbler leak
3. Furmanite guns
4. Corrodograph survey