This includes a comprehensive desk based survey, and if appropriate an intrusive fire safety survey of the external walls as well as the common parts and flat entrance doors .
Mae hyn yn cynnwys arolwg desg cynhwysfawr, ac os yw'n briodol arolwg diogelwch tân ymwthiol o'r waliau allanol, yn ogystal â'r mannau cyffredin a drysau mynediad i fflatiau .