IT hardware generates unusual concentrated thermal loads while being very sensitive to changes in temperature or humidity. Fluctuations in temperature or humidity can create problems such as garbled processing or even complete system shutdown in severe cases, so maintaining temperature and humidity design conditions is critical to the smooth operation of a data room.

The design conditions should be 22°C to 24°C (72°F to 75°F) and 35% to 50% relative humidity (R.H.). Like damage that may result from unsuitable environmental conditions, rapid fluctuations in temperature may also negatively affect hardware operation, which is one reason why it is important to keep the hardware running even if it is processing data at the end of the day. In contrast, comfort air conditioning systems are designed to maintain indoor temperature and humidity at 27°C (80°F) and 50% R.H., respectively, at 35°C (95°F) and 48% R.H. outside in summer.