This document specifies limit states, requirements and methods to prevent mechanical hazards in steel structures of cranes by design and theoretical proof of competence. The significant hazardous situations and hazardous events that could result in risks to persons during intended use are identified in an informative Annex L (informative). Clauses 4 to 8 of this document provide requirements and methods to reduce or eliminate these risks: a) exceeding the limits of strength (yield, ultimate, fatigue); b) exceeding temperature limits of material or components; c) elastic instability of the crane or its parts (buckling, bulging). This document does not apply to cranes which are designed before the date of its publication as EN. NOTE This document deals only with the limit state method in accordance with reference [44].