The Hydrogen and Industrial Medical Gases (NFPA 2 and NFPA 55) technical committees have formed a joint task group to look at separation distances for liquid and gaseous hydrogen. Hydrogen fueling stations for fuel cell vehicles are currently being built in California and are planned for the Northeast and the rest of the country. Separation distances in the codes have presented a challenge for the installation of new stations. The group is working on developing the basis for and modeling release scenarios that can be used to establish safe separation distances. The goal of this work is to develop public input for the 2019 edition of both documents.