Cleanroom ventilation automation for a pharmaceutical production plant

The brief

A pharmaceutical manufacturer was rebuilding a production block to a classified cleanroom standard. The mechanical design was fixed; what was missing was the automation layer — control strategy for the air handling plant, the pressure cascade between classified zones, and documentation that would survive a qualification audit.

What we did

We started from the mechanical schematics and the room classification matrix. Each classified room was assigned a target pressure differential relative to its neighbors, and the cascade was resolved as a single coordinated scheme rather than room by room, so that door interlocks and airlock sequences did not fight each other.

From that scheme we produced the control philosophy, a full I/O schedule across five air handling units and the associated terminal devices, panel schematics for the control cabinets, and the alarm and trend configuration for the monitoring station.

Delivery notes

Because the plant was on a qualification path, every document was written to be traceable: sequence sections carry reference numbers that the I/O schedule, the panel schematics and the functional test procedures all cite. When the client’s validation consultant asked how a specific interlock was implemented, the trace from requirement to terminal number was a two-minute exercise rather than a two-day one.

The package was delivered in three increments — plant, distribution, terminal devices — with a review call at each hand-off.