Achieving favorable therapeutic outcomes in one's procedure(s) is dependent on the calibration of the PDT device as well as the accuracy of the calibration performed. Calibration ensures that the PDT device produces light of optimal wavelengths which are capable of stimulating the biological processes of collagen production and tissue repair. Regular calibration is not only essential to treatment efficacy but also helps in prolonging the life of the device. To ensure deviation of measurements is within acceptable limits, well-defined operational procedures from the manufacturer must be adhered to which may include regular and preventative maintenance, and the use of calibrators, where available. This approach will undoubtedly enhance the control measures within the practice to ensure the desired health outcomes from treatments are achieved.