HOW to determine the time after cleaning till new product preparation

Hi all, now I am performing cleaning validation in our plant.We produce water based solutions for IV and IM infusions and injections.Everything is clear for me in cleaning validation, only I want to know if there are any references for time between cleaning and producing or we have to choose it and validate it practically.If we have to validate it what will be the worst case.Sometimes we stoopped production for several days or for vacation.Before it we sterilize lines and tanks with pure steam.If someone has some ideas please write.

Clean hold time is generally considered to be the time between the completion of cleaning and the initiation of the subsequent manufacturing operation.
FDA: Guide to Inspection of Validation of Cleaning Processes
The European Union wants companies to provide a validation master plan with clearly defined and documented validation program elements

Thank you Mr. Prasad.I know what is clean hold time, I only want to know is there any references where I can see specially the time between last wash and production cycles, for example 6 hours, or 10 hours.If we washed and sterilize production tanks and lines after what time we have to sterilize it again?Or we have to establish the time after experiments.

Your hold times are to be scientifically evaluated and documented. There is no time limit as per FDA guidance or rules. The reason is everything that comes into contact with Tank from your product to detergent, Water to steam, Drying temperature or flushed filtered compressed air should be in a state of quality and fit for purpose.
Multiple factors influence your clean hold times.
Few factors are : How you store vessels?
Where you store?
How good are the washing materials?
How good your sterilization process is?
How good your removal of last droplets of water and or Drying process is ?

This has to be controlled well at your end and show FDA scientifically the reasons for your Clean Hold Time in Hours or days or weeks or months etc.

Everything must be establish with sound experimentation and with Bioburden analysis.

Thanks for information.