This  International  Standard  provides  general  requirements  and  procedures  for  the  assessment  of  existing structures  (buildings,  bridges,  industrial  structures,  etc.)  based  on  the  principles  of  structural  reliability  and consequences of failure. It is based on ISO 2394. It is applicable to the assessment of any type of existing structure that was originally designed, analysed and specified based on accepted engineering principles and/or design rules, as well as structures constructed on the basis of good workmanship, historic experience and accepted professional practice. The assessment can be initiated under the following circumstances: an anticipated change in use or extension of design working life;  a  reliability  check  (e.g.  for  earthquakes,  increased  traffic  actions)  as  required  by  authorities,  insurance companies, owners, etc.;  structural deterioration due to time-dependent actions (e.g. corrosion, fatigue); structural damage by accidental actions (see ISO 2394). This International Standard is also applicable to heritage structures provided additional considerations shown in Annex I are taken into account. This  International  Standard  is  applicable  to  existing  structures  of  any  material,  although  specific  adaptation can be required depending on the type of material, such as concrete, steel, timber, masonry, etc. This  International  Standard  provides  principles  regarding  actions  and  environmental  influences.  Further
detailed considerations are necessary for accidental actions such as fire and earthquake. NOTE         Fire resistance requires properties different from those for structural safety and integrity. Also fire hazards can be  created  by  change  in  use.  Special  requirements  are  necessary  for  seismic  hazards  taking  the  dynamic  action  and structural response into account. This  International  Standard  is  intended  to  serve  as  a  basis  for  preparing  national  standards  or  codes  of practice in accordance with current engineering practice and the economic conditions.