Non compliance of a product is usually because the Gas Board, Gas Regulators, Government Agency, etc have determined that the unit is unsafe to use under certain conditions. I have no idea why yours doesnt comply but it would be something to do with safe operation. In Australia for instance, any gas appliance sold here, must meet AGA requirements and have an AGA Approval decal on it with an authority number. The oven you have probably doesnt carry a Government approval and this would make it illegal for a Gas Tech to instal it. I would suggest you contact the supplier for more information. It is strange though that they would be allowed to sell a unit that doesnt comply.