The temperature of air affects its density. When air heats up it expands, and when it cools it contracts. Because of this and other effects, we need to make an air density adjustment. For example, if you performed a test on a house when the inside temp was 70 and the outside temp was 0, and then performed another test on the same house (in the same physical condition) when the inside temp was 70 and the outside temp was 90, you would expect to see test results differences of about 8%, if you didn't make corrections for temperature.
Corrections for differences in air density due to temperature are automatically made in our TECTITE software using either the CGSB or RESNET test standards. Because of the way the CGSB test standard deals with air density, you do not need to correct for altitude. The RESNET test standard in TECTITE will have you enter the altitude for the test location so it can make corrections for altitude.