How many ways are there for Duct leakage testing? And what is the most suitable one?

Light test for low static ducts, smoke test for specially kitchen extract....

The most suitable way to conduct leak test for HVAC ducts is Light test.

Most and only efficient way, and i think very cheap too.

Other tests is smoke and pressure test.

Smoke Test ,Light Test  and Pressure Test

Light test, Smoke Test, Pressure Test. Smoke test is the efficient and economical, how ever light test is being considered easiest method on low pressure system and easiest and efficient to perform and get result.

Light test, Smoke Test, Pressure Test. Generally light test is being done on low pressure system and easiest and efficient to perform and get result.

Light test - Smoke Test - Pressure Test.

I believe light test is the easiest and most efficient.