From Wikipedia

 Pay Attention Britain!

 Public Information Films (known as PIFs) are a series of government commissioned short films, shown during television advertising breaks in the UK. The US equivalent is the Public Service Announcement (PSAs).

The films advised the public on what to do in a multitude of situations ranging from crossing the road to surviving a nuclear attack. They are sometimes thought to concern only topics related to safety, but there are PIFs on many other subjects, including animal cruelty, protecting the environment, crime prevention and how to vote in an election or fill in a census form.

Many of these films were aimed at children and were shown during breaks in children's programmes during holidays and at weekends. The general low-budget quality and the infamous static "crackle" before them gave them a Hammer Horror style aura. Some of them were quite terrifying and remained ingrained in the child's psyche well into adulthood, others were quite humorous and used comedy to show the dangers or ridicule the folly of those who ignore them (Joe and Petunia are a good example of a comic PIF). Many of them involved or were narrated by celebrities of the day.