Phone number 1300 00 INOX (4669)
Home / Technical data / Extract from building-authority approval Z-30.3-6
Extract from building-authority approval Z-30.3-6

Tab. 19: Subdivision of steel grades by strength class and corrosion resistance class

1) According to DIN EN 10088-1:2005-09
2) A = austenite; F = ferrite; FA = ferrite-austenite (duplex)
3) The strength classes following the lowest strength in each case are achieved through cold work hardening by means of cold working.
4) B = sheet; Ba = strip and sheets produced from it; D = wire, drawn; H = hollow profile; P = profile; S = bars; W = wire rod
5) Applies to metallically bare surfaces only. The more base of the metals is at risk in the event of potential contact corrosion.
6) For the corrosion resistance classes required, see Table 11.

Tab. 20: Material selection for atmospheric exposure


1) Regular cleaning of accessible construction or direct surface irrigation will significantly reduce exposure to

corrosion such that the result can be reduced by one corrosion resistance class. If it is possible that the concentration of materials on

the surfaces may increase, one corrosion resistance class higher should be selected.

2) Regular cleaning of accessible construction can significantly reduce exposure to corrosion

such that one corrosion resistance class lower is possible.

3) If service life is limited to 20 years, reduction to corrosion resistance class I is possible if localised corrosion

of 100 μm is tolerated (no visual requirements).

4) Constructions are graded as inaccessible if their condition cannot be monitored or is very hard to monitor

and if they can only be reconditioned at great cost in the event of fire. 

Tab. 21: Steel grades for fasteners with assignment to steel groups following DIN EN ISO 3506


Parts 1 and 2 and labelling following Section 2.2.2 and maximum nominal diameter


1) According to Table 10
2) Since there are no standard definitions at present, these steels should be labelled with the material number.
3) Appendix 7 of the general building-authority approval
Z-30-3.6 from 20 April 2009 applies to fasteners in indoor swimming pool atmospheres. See Table 10.