A universal leak detection method for detecting both small and large leaks. The method includes the steps of: injecting smoke and a detectable gas into a fluid system to pressurize the fluid system, the smoke and detectable gas both being capable of passing through a large leak in the fluid system, and the visual smoke particles being inhibited from passing through a small leak in the fluid system and the detectable gas being capable of passing through a small leak in the fluid system; and detecting a leak by detecting at least one of the smoke and the detectable gas, wherein detection of smoke is indicative of the fluid system having a large leak and detection of detectable gas without smoke.