A Metrology Lab Pressurised Plenum Heating, Ventilation, and Air Conditioning (HVAC) system is specifically designed to maintain precise temperature, humidity, and air quality control in metrology labs where sensitive equipment and measurements are in use. The pressurised plenum system serves to provide a stable and well-regulated environment for consistent and accurate measurements.
In a Pressurised Plenum HVAC System:
- Conditioned air is supplied to the lab space through a central air handling unit (AHU) that is responsible for regulating temperature and humidity to the required setpoints. AHUs typically consist of filters, heating and cooling coils, dampers, and fans.
- The AHU forces air into a pressurised plenum (a dedicated air space) that is often located above the lab ceiling or below the floor. The pressurised plenum works as a reservoir to distribute conditioned air evenly throughout the lab.
- High-efficiency particulate air (HEPA) filters are often installed to ensure the cleanest possible air quality, as contaminants can negatively impact the accuracy of metrology measurements.
- The conditioned air is then distributed into the lab through specially designed supply air diffusers that ensure uniform airflow and minimum turbulence.
- The HVAC system typically operates continuously and maintains a constant positive pressure in the lab to keep contaminants from entering the space.
- Exhaust or return air vents remove air from the space, controlling airflow patterns and ensuring proper air exchange with the external environment. The balance between supply and exhaust airflow must be carefully controlled to maintain pressurisation.
By maintaining a pressurised plenum and controlling the air quality, temperature, and humidity, the HVAC system helps create a stable and clean environment within the metrology lab, which is essential for accurate, repeatable, and precise measurements.
