As for Hard Anodizing, the utensils must meet the following requirements. Portaria No. 499, 20/12/2021 clause 4.2.3.2 Ordinance No. 499 20/12/2021 clause 4.2.3.2 Thickness: The minimum measured thickness of the hard anodized layer, in cases where it is not covered by other types of coating, shall be 25 μm. Portaria No. 499,20/12/2021 clause 4.2.3.2.1 Ordinance No. 499 20/12/2021 clause 4.2.3.2.1 Stain resistance: There must be no visible stains on the surface that comes into contact with food. Portaria No. 499, 20/12/2021 clause 4.2.3.2.2 Ordinance No. 499 20/12/2021 clause 4.2.3.2.2 Resistance to Alkali: Current flow cannot occur. Portaria No. 499, 20/12/2021 clause 4.2.3.2.3 Ordinance No. 499 20/12/2021 clause 4.2.3.2.3 Hardness: The hardness must be greater than 350 HV 0.5. Portaria No. 499, 20/12/2021 clause 4.2.3.2.4 Ordinance No. 499 20/12/2021 clause 4.2.3.2.1