The knowledge of the ignition behavior of dust-air mixtures due to electrical sparks (MIE, Minimum Ignition Energy) and hot surfaces (MIT, Minimum Ignition Temperature) is important for risk assessments in chemical production plants. The ignition behavior determines the extent and hence the cost of preventive protection measures This paper describes the use the minimum ignition energy and minimum ignition temperature as very important safety indexes in practice. Based on the latest results from large scale experiments on pneumatic filling of silos with polymeric materials and new results of full scale filling tests using flexible Intermediate Bulk Containers (FIBC) manufactured from a variety of materials, guidance can be given to ensure safe operation in different situations such as filling, emptying operations, type of powder handled. The aim of this paper is to assist people dealing with product. It reflects the present state of the art and current knowledge of the assessment and measures association with powder handling.