This was I'm guessing 15 years or more back - I don't have that any more.
Tbh, I'm not sure whoever it was from HSE was certain (given the unusual circumstances of industrial-size equipment in a domestic type setting - & went "on the safe side" (as one might expect).
Given that Garages and other workplaces are meant to have segregated battery storage areas & battery rooms etc (& the packs were around 1000AH @ 24vdc nominal or 550AH @ 48vdc nominal and filled a pallet-sized space pretty much) my suspicion is they went with prudency.
Seeing as we were responsible for the safety of the installation, and potentially liable were there ever an incident & it was investigated..... we consulted and went with established, sensible practices regarding battery storage.
We had always done so anyway... but I ended up going to HSE to get s 2nd opinion from a regulatory authority..... because we had one crazy Dutch woman whose business was doing lectures on Sustainability/Green Living etc as a client. She wanted to make a feature of her system & flaunt it, not have the industrial kit squirrelled away.... & wanted her (Rolls) battery pack stacked over 3-tiers on a bespoke shelving unit, clad in clear perspex, as a feature in the entrance hallway of the house! The pack would be right at the bottom of the stairs too (the only egress from upstairs where she, her husband and her young daughter slept)!
The woman should have been an Oceangate Sub Pilot/Owner! She was arrogant as hell & refused to accept there was any increased risks to her family or property by having a very big electrical storage unit & potential fire/explosion source.... right in the path of the only escape route inside her home!
(IMO living proof that you cannot fix stoopid, only breed it).
Given that we were the suppliers & installers / commissioners of the system - no way was I going to leave the company open to a possible future manslaughter charge to satisfy the whims of this woman - so I covered our backsides, basically.
