One of the calibration problems posed by the new generation of mid-infrared instrumentation on 8--10~m class telescopes is that of polarimetric calibration. To be able to calibrate polarimetric data reliably it is necessary to be able to measure both the instrumental polarization and the efficiency of detection of polarization with a high degree of accuracy. In many senses the problems are less difficult than for spectrophotometric calibration, but still need to be defined and overcome. In this article we discuss the polarization calibration problems relevant to the mid infrared that are applicable to infrared instruments as the CC-Pol module of CanariCam---the mid-infrared imaging spectrograph for the GTC---which will cover the range from 8 to 24 μm. It is a part of the photometric, spectrophotometric, and polarimetric calibration for the CanariCam project (Martín-Luis et al.~2001).