design condition on nozzle

Dear friends

Is it necessary to consider design condition on equipment nozzles? and is it necessary to consider hydrotest condition on them?
Do we have any standard about this issue?

Thank you

For design condition , I think it is necessary.
For example the different temperature of nozzle outside and nozzle inside has a big effect on nozzle stress.If no insulation used on nozzle.
For WRC, I don't whetehr there has a special consideration for this temperature difference.
But in NozzlePro, it is considered.