Crack 5 : An irregular, unplanned opening which is essentially vertical and of various widths which may intersect with others, oriented longitudinally (that is in the direction of traffic) wandering transversely or a combination
Peter Milne and Kieran Sharp, ARRB Group, and Bob Ungers, consultant, Austroads Glossary of Terms (4th Ed.), Austroads Ltd., Sydney, NSW, Australia 2010. http://www.bicyclensw.org.au/files/u1/Austroads_Gl ossary_of_Terms_4th_edition.pdf (Road Trfc and Transp Sfty - Brit) {529}