UCVS Upgrades

Ultra Clean Ventilation Systems are a major capital investment designed to provide you with a contamination-controlled environment. Since the conception of Ultra Clean Ventilation for deep wound surgery in the early sixties great strides have been made in the design of these systems. To improve the downflow velocity, noise level and more importantly the capability to maintain sterility within the Clean Zone. Today's Ultra Clean Systems achieve this with the improvements in fan technology and filter manufacture.

Unfortunately a vast majority of installed Ultra Clean Systems do not. There are many reasons for this, the most important being the test methods employed at the time of commissioning. For many years the content in BS 5295:1976 Environmental cleanliness in enclosed spaces, the specification for controlled environment clean rooms, work stations and clean air devices was applied.

The requirement for testing Laminar Flow in BS 5295 1976 was that a series of readings, taken with a rotating vane anemometer 100mm from the filter face, to determine the mean velocity of the filter. The minimum mean downflow velocity had to be 0.38m/sec. This was achieved 100mm from the filter face but not at the two-metre from floor level. This impacted on the one-metre from floor level velocity readings. Once HTM 2025 was published in 1994 difficulties arose in the capability of these units to achieve 0.20m/sec at the one-metre from floor level. In general this was not seen as an issue by the manufacturers as it posed no infection worries. As time has progressed with HTM 03-01 replacing HTM 2025 and combined with the fact we live in an era of litigation more emphasis has been aimed at these short falls.

The options:

• Do you replace the unit?
• Do you upgrade the unit?

Considerations

• Cost
• Theatre downtime

VtV Solutions will help you with the considerations around the best course of action for upgrading your operating theatre.

VtV offer the chance to upgrade existing Ultra Clean Ventilation Systems for full compliance with HTM 03-01. Should the minimum requirement of 0.38m/sec. two metres FFL be met then any Ultra Clean System, regardless of age or make, can be upgraded. The only drawback may be a slight increase, undetectable to the human ear, in the noise level. The costs compared with replacing the unit are minimal and the Theatre downtime is restricted to one day. If the case is that 0.38m/sec. at two-metre FFL cannot be achieved then the only option is to replace the unit.

Validation Protocol Includes:

• HEPA Filter Installation Leak Testing
• Downflow Velocity Profiling
• UCVS Entrainment Assessment
• Airborne Particulate Monitoring