Given this was a block of flats, any explosion could have been very serious.
You also have to question the ability if not the sanity of the site manager.
Finally, all gas installations are supposed to be tested so quite how this obviously serious gas leak was not detected will remain a mystery.
What will it take before housebuilders build new homes properly, test their installations properly, investigate customer complaints properly and employ site managers who know what they are doing? (or at least can tell the difference in smell of new paint from gas!) Does a block of flats have to explode or burn down perhaps with loss of life?
It is now time that the house builders that fail, should be de-registered by the new home warranty providers.
They won't sell many new homes without a warranty!