As | Cd | Cr | Cu | Fe | Hg | Ni | Pb | Sb | Ti | V | Zn | MMI | |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
1990 - 1995 | – | – | Aa | Zc | Aa | – | Aa | Aa | – | Aa | Aa | Za | Aa |
1990 - 2000 | – | – | Aa | Aa | Aa | – | Aa | Aa | – | Aa | Aa | Zc | Aa |
1990 - 2005 | – | – | Za | A | Aa | – | Aa | Aa | – | Aa | Aa | Za | Aa |
1995 - 2000 | Aa | Aa | Ac | Aa | Aa | Ac | Aa | Aa | Aa | Aa | Aa | Aa | Aa |
1995 - 2005 | Aa | Aa | Za | Ab | Ac | Ab | Ac | Aa | Aa | Aa | Aa | Ac | Aa |
2000 - 2005 | Zc | Aa | Za | Zb | Zc | Ab | Zb | Aa | Ac | Zc | Ac | Za | Za |