cooker install

Hi folks,
I live in ROI and have just fitted a new kitchen in a new extension to my house. I've been reading this thread ref fitting a gas cooker and need a bit of advise please:
My cooker set-up comprises an inset Whirlpool gas hob sited over a Whirlpool electric oven in the correct cabinet carcass. The hob has a threaded brass male connection underneath and the capped-off gas supply pipe is poking out of the wall approx 1.5m away underneath further base units. I don't intend make the hob connection myself but I would like to know what I should see when the gas fitter has finished doing his job.
Like:
Should the connection be made in copper or flexible pipe?
Should there be some regulator or NRV in the line?
What does the pressure reduction test entail?
Thanks for your help,
Dave

MOD 2

split from hijacked post

ROI might be different, but in UK it would usually have to be in copper, with a suitable isolation valve, and a maximum pressure drop with all appliances on, of 1mbar.