A feasibility study was undertaken to determine if radiochemical neutron activation analysis (RNAA) can be used to certify the retained dose of phosphorus implanted in silicon, with the goal of producing a phosphorus SRM. Six pieces of silicon, implanted with a nominal phosphorus dose of8.5×1014&hthinsp;atoms⋅cm−2were irradiated at a neutron flux of1.05×1014&hthinsp;cm−2⋅s−1.The samples were mixed with carrier, dissolved in acid, the phosphorus isolated by chemical separation, and32Pmeasured using a beta proportional counter. A mean phosphorus concentration of(8.35±0.20)×1014&hthinsp;atoms⋅cm−2(uncertainty=1standard deviation) was determined for the six samples, in agreement with the nominal implanted dose. ©2001 American Institute of Physics.