Water Heater Mixing valve?

I am looking for the date that the mixing valve for the gas water heaters became code for Ontario, thanx in advance.

Memory tells me it was Jan 1 2005 . I think if the permit was taken out before that it might not apply. They at this time are still replacing water heaters that are worn out and not putting in the valves . The laws says they must.
Another trick if you can not get the water hot enough from the mixing valve take the red cover of and there is an adjustment inside .
Roy Cooke

attached read q/a #4

Great Thanks Claude Missed you have you been away Hope every thing is fine.
Roy Cooke

Thanx Claude and Roy!