1.1 Field of application This standard is applicable to unshieldsed tunnel boring machines, TBM's, and rodless shaft boring machines, SBM's, and their towed or attached back-up equipment for driving tunnels or shafts in rock where the whole area is excavated in one or more steps by mechanical means. It specifies essential safety requirements for the design, construction and maintenance of such machines when used in non-explosive atmosphere together with the methods of verification. The standard specifies monitoring for hazardous atmosphere. For TBM's and SBM's which are to be used continuously in explosive atmosphere, additional relevant standards also apply. This European Standard deals with all significant hazards pertinent to unshielded tunnel boring machines and rodless shaft boring machines for rock, when they are used as intended and under the conditions foreseen by the manufacturer (see clause 4). This European Standard specifies the appropriate technical measures to eliminate or reduce risks arising from the significant hazards.