a safety device is applicable in association with an aperture made in a floor , or work , support or bearing plane , through which a service element passes with a substantially longitudinal development , such as a pipe , tube , cable - conduit and suchlike . the safety device is usable to completely close the empty space defined between the peripheral edges of said aperture and the transverse bulk of said service element . the safety device is formed by a plurality of modular sections to define a base body , suitable to completely surround said service element , which functions as a closing barrier of said empty space and which can be configured to define an internal passage in order to house the service element to size .