Probably the most reported problem with central vacuum systems – aside from failure over time from corrosion – is the instability of the vacuum supply. Each user’s demand often causes pressure spikes and dips in the vacuum received by other users. Somewhat less noticed, but of probably greater impact, is the risk of cross-contamination through vacuum systems.
Consider that, once vacuum is established at one workstation on a central vacuum system, opening another port creates higher pressure at the point at which air or new vapors enter the system. Flow within the piping naturally flows from the point of higher pressure to the area of lower pressure. This means that vapors or aerosols from one application can be transferred to another workstation, resulting in contamination. Risk of such contamination is a serious concern in life science labs, as reflected in this article about critical research being compromised by contamination of cell lines.
Three options exist to reduce the risk of cross-contamination through vacuum lines. The first is simply good lab practice; a sterile filter should be used on any vacuum application in a biological laboratory that derives vacuum from central supply. Greater assurance is provided, however, by vacuum supply that is completely isolated from other sources of contamination. VACUU·LAN® local vacuum networks create vacuum within the lab for multiple users, ensuring that there is no path through vacuum lines for contaminants from other labs. Another option is a point-of-use, self-contained aspiration system like the VACUUBRAND BVCprofessional G. With an integrated vacuum pump, receiving flask, sterile filter, and liquid level sensor to prevent flask overflow, these systems produce vacuum on demand for cell culture work and provide total isolation from other applications, preventing risk of contamination through vacuum lines.