Yes for gas work. Gas Safe Register states that anyone carrying out gas work as part of a business must be competent and registered. That includes installing, reconnecting, servicing, repairing, altering, moving or removing gas fittings where the work falls within the legal definition of gas work.
A homeowner should not remove a combustion-sealed boiler casing, disturb gas-carrying components or attempt to repair the gas side of an appliance. Safe user tasks described in the manufacturer's instructions are different, but gas work itself is not a DIY job.
Doherty Plumbing & Gas displays Gas Safe registration number 950808 on its website. For Glasgow boiler installation, servicing or repair, checking the engineer's Gas Safe registration is one of the basic steps before work begins.
