Vacuum Leaks

Real Vacuum Leaks

These leaks are penetrations or passages through the freeze dryer vessel or vacuum system: the chamber, the condenser if externally condensing, the vacuum lines, or the vacuum seals. A leak may be due to a single source, or multiple sources of smaller leaks.

Virtual Vacuum Leaks

A virtual leak stems from a gas supply that is contained within the interior of the freeze dryer, not from a flaw in vessel integrity. A virtual leak may initially appear as either a trivial leak or an operating leak, although a leak rate high enough to qualify as a gross leak is possible.

Even when the virtual nature of this leak has been identified, it can still be a difficult task to determine the source and location of the outgassing. Virtual leaks are generally harder to find than real leaks because the source can be anywhere within the system's interior and can be as diverse as oils from a handprint, lint or other porous materials, mucilage from tape, or residual moisture.