Zinc coated thickness are required by each standard following:

TIS 770-2533, Article 6.2.2
Above 20 microgram

UL 797, Article 6.2.2
Above 20 microgram

ANSI C80.3, Article 6.2.2
Above 20 microgram

Zinc Galvanised steel grade available:
Z060
Z080
SGCCM