Hi Shazm1 and welcome to the forum,
This is a new one on me.
In England if you are renting out your property, a landlord is required to have a Gas Safety Test Certificate done once a year I believe, but I have never heard of this if you are living in your own park home.
If you are renting from the park owner, it would be he/she who would have to supply this certificate as the Landlord, as the park home would be their property.
You might like to try giving the Technical Division of the National Caravan Council a ring on 01252 318251 for clarification.
Let us know what happens!
Regards
Ed
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