Versions of Iowa Code 272.20 - National certification on LawServer 2023 Iowa Code 272.20 – National certification 2022 Iowa Code 272.20 – National certification 2020 Iowa Code 272.20 – National certification 2018 Iowa Code 272.20 – National certification 2016 Iowa Code 272.20 – National certification 2014 Iowa Code 272.20 – National certification. 2009 Iowa Code 272.20 – National certification