Erroneous readings often result from attempts to measure the temperature coefficient of input offset voltage. This parameter is actually a calculation using input offset voltage measurements obtained at two different temperatures. When one (or both) of the temperatures is less than freezing, moisture is able to collect on both the device and the test socket. This moisture results in leakage and contact resistance that potentially causes erroneous input offset voltage readings. The isolation techniques previously mentioned have no effect on the leakage because the moisture also covers the isolation metal, thereby rendering the techniques useless. Perform these measurements at temperatures greater than freezing to minimize error.