Apparently these panels are designed to be broken open by the Fire Brigade or to provide people in the basement with the means to escape.

Essentially, when you walk on these you're walking on a trapdoor.

http://www.luxcrete.co.uk/concrete_products/escape_access_hatches/index.htm

http://www.luxcrete.co.uk/datasheets/LUXCRETE_ESCAPE_ACCESS_HATCHES.pdf

A new low? Yeah probably, but I don't care. HA HA!