I don't speak for Telcordia, but I believe their position was somewhere along the lines that a total ban was not needed. Its like banning all electrical wiring above the 3rd floor because fires have started in electric wires. Instead Bellcore offered an alternate proposal with rules how such battery rooms should be constructed to mitigate the risks. The nicest battery plant I've ever seen was at the Bellcore training facility outside of Chicago. On Thu, 30 March 2000, "Henry R. Linneweh" wrote:

This is disturbing, I think that people, environment and property are the crux of importance in the order stated.

Above the 3rd floor is a risk to human life and therefore unacceptable, being A First Responder Operational (FRO) I can clearly see this as a serious risk, technical details of burning acid fumes omitted.