[en] There has been some criticisms of the maximum permissible organ burden (MPOB) in bone for ²³⁹Pu in recent years. These criticisms allude to the relative dearth of experimental data available concerning the actual dose delivered to the endosteal face of osseous tissue by the ²³⁹Pu alpha particle. A dosimeter recently developed has been recommended for application to this microdosimetry problem. The tissue equivalence of polycarbonate dosimeters would allow dose equivalent to be read directly from the foil rather than determining activity from emulsions, in which the alpha particle range is different than in tissue, then relating this activity measurement to absorbed dose by some calculations. Although this dosimeter has been calibrated to read dose equivalent for fast neutron dosimetry, the need exists to determine the factor to multiply by the number of ²³⁹Pu alpha-induced tracks to obtain dose equivalent. This problem is being approached in the following manner. A device called the vacuum-sealed alpha-calibrator has been designed and constructed which will allow the handling of a standard ²³⁹Pu solution obtained for this purpose. The calibrator will first be connected to surface barrier detectors which feed data into a multi-channel analyzer. The counts obtained under the alpha peaks at various heights above the source and the accumulated time are input into a computer program recently written to convert this data into dose rate in rems/unit time. Next the measurements are duplicated, this time using the polycarbonate dosimeter. The results will produce a factor relating the number of alpha-induced tracks to dose