Area classification in cleanroom

What is the meaning of ‘at rest’ and ‘in operation’ states in cleanrooms

at rest mean no working activity
in operation mean in working condition

Each description is described in norm ISO 14644-1 and cGMP

Hi Omkar,

These terms are typically applicable to areas that are catered to by an air handling unit (AHU) as a particular class has to be defined or stated for the area. .

‘At rest’ conditions imply when there is no machinery running in the area as well as there is no man-material movement.
‘In operation’ implies that the machinery is running and there is man-material movement.

While designing an AHU, the classification of an area is always considered as its ‘at rest’ condition.

Hi. I am conducting HVAC PQ for new facility. We have not produce anything. So what can I do to create a ‘working condition’? Or I just need operator and run all equipment for 24/7? Thank you.