You should be guided by you sector and any regulations, standards or specifications applicable to your scope of work and tests being performed. For example, the requirements for Food and Agriculture differ from Health and medicine. The intention is that conditions should not adversely affect the validity of your results. Look to guidance documents for your specific sector, e.g. from the FDA, USP or EU on microbial controls. There are also a number of ISO Standards, for Example ISO 14160:2020 Sterilization of health care products — Liquid chemical sterilizing agents for single-use medical devices utilizing animal tissues and their derivatives — Requirements for characterization, development, validation and routine control of a sterilization process for medical devices.
There is a clear need to perform a risk assessment for each test or calibration method and associated activities in the laboratory’s scope of work. Then you can determine what facilities and environmental conditions are suitable and what controls (measures) are required to provide the consistent conditions.