Doctor Who Children in Need Sketch Filmed at Roath Lock Studios

I can confirm that a Doctor Who Children in Need sketch was filmed at Roath Lock Studios on August 7. A photo exists of a safety bulletin posted outside of the studios used for Doctor Who.

An official #DoctorWho #ChildrenInNeed sketch is happening!

Recently discovered by visitors to Roath Lock, the doors to the Doctor Who studio state that filming for a children in need sketch was taking place! Which includes “water, slips, trips and falls”

Who’s excited?? pic.twitter.com/ue7Jw5CQNt

— Tardis Tales💥🌎 (@TardisNew) August 7, 2018

I've privately seen this photo myself, though not from the person who tweeted about it. I can confirm the safety bulletin says "Doctor Who/Children In Need" and contains handwritten warnings for

Slips, trips and falls
Water
Overhead washing

I would venture to guess that "Overhead washing" refers to some sort of water-releasing apparatus used in filming to simulate rain.

I would also guess that the photo was possibly taken by someone who was partaking in a tour of the Pobol y Cwm set which was offered that day in the same studio complex.