Challenges to the assembly and integration of the WSS with METIS

The METIS consortium in Portugal will build the support and access structure (WSS) for the mid-infrared, first generation ELT instrument - METIS. The specific characteristics of the METIS instrument and the ELT pose several challenges to building the WSS according to functional requirements. In addition, the assembly of the WSS and integrating the WSS with METIS poses its own particular challenges due to the singular loads and dimensions. Transversal to all phases of assembly and integration of the WSS and METIS is the concern for the safety of the instruments and personnel involved. We here present these requirements, challenges and mitigation measures in light of the assembly and integration of the WSS, and the WSS with METIS.