1 – What level of humidity is required and what level of fluctuation is acceptable?
Different applications will require different levels of humidity control. The most common application for a HVAC consultant will be the office environment’s requirement of between 40-60%rH (relative humidity). At this level people are comfortable and static build-up is reduced.
Many manufacturing industries will require a more specific level of humidity control. For instance printers need to control humidity to a tighter 50-60%rH. Textile manufacturers will need a higher 65-75%rH. An ideal museum environment is between 45-55%rH but with daily fluctuations being limited to ±3%rH to safeguard valuable exhibits. Some pharmaceutical applications need an even tighter ±2%rH to prevent product wastage.
If an application requires tight control of humidity then the humidifier selection will be restricted to systems that give very fast responses to a drop or increase in humidity, like resistive steam or spray units. Water treatment may also be required to improve the consistency of performance.