ISO 12944 Understanding the thickness guidlines

[marcusja2002]

I'm reading through ISO 12944 and it doesn't indicate if those mil thicknesses are meant as a minimum or if there is an actually range intended here. I'm specifically looking for the 3C Amerlock series spec. When we receive it in, it has a lot of orange peel, so I dont know if this is expected with this thickness, or there is a specific way it should be put on to ensure a smooth, yet thick coat.

Thank you in advance for those in the know. This is a new spec for me.