As the number of engineered nanomaterials (ENM) used in research increases with an incredible speed, health and safety specialists are continuously faced with the challenge of evaluating the risks involved with these materials. Nowadays there is not enough information about their toxicology and new materials are continuously being developed. Preliminary scientific results indicate that ENM might have a damaging impact on human health, which makes it even more important to have the right mitigation measures in place. To address this challenge, a practical risk management procedure for working with ENM is presented. The task of choosing preventive and protective measures is largely simplified with a schematic decision tree approach that allows for a simple determination of the hazard level and Nano classification of a laboratory with three control bands. The methodology is adaptive and learning based, and it takes into account both the hazard level of the ENM and the exposure. The usefulness and completeness of the methodology is demonstrated with an extensive classification of the activities involving ENM in one of the EPFL research units. The research group handles inorganic nanomaterials both in powder form and in suspension. This classification allowed for a complete hazard and risk mapping, which facilitates resource allocation decision-making. This was demonstrated with the proposition of a set of technical, organizational and personal mitigation measures that has since then been implemented in the laboratories.