It is dear that humans are exposed to ionizing radiation both of internally or externally in radiotherapy. The determination of ionizing radiation dose in human blood has been previously performed by us using optically stimulated luminescence technique. OSL technique is based on measuring the luminescence intensity from a sample that has been exposed to ionizing radiation. In this study, the detrapping constants for human blood samples were investigated using Curve-Fitting, Active OSL-Approximation and Linear Modulation techniques. The Active OSL-Approximation was based on the radioactive decay law of successive disintegration. It allows obtaining the peak forms of luminescence signal. It has been observed that the decay rates for blood sample exposed to different radiation doses were changed with dose. AOSL- Approximation is appropriate for separating the peaks that correspond to decay rates.