The answer Phil is right in front of you in your codes. You don't need fire doors on a wc or bathroom unless it contains a fire risk.
The question you and me have to ask ourselves is, is the electrical equipment contained therein a fire risk?
Can electrical equipment go on fire?.
Bit more to it than that Nearlythere.
Yes we need to consider if the electrical equipment is an ignition risk......I would suggest it always is,........... if ignition occurs what fuels are available?
Then we need to take into account room geometry, wall, floor and ceiling linings, ventilation, ceiling height, we can then determine likely rate of development.
Then I suggest we look at who may be in the building at the time, asleep, awake, infirm, drugged, drunk etc.
What means of raising the alarm is in the low risk room, that shouldn't have a fire anyway? What assistance is available to initiate an effective evacuation?
Or alternatively we could read the guide and say we dont need fire doors on wcs or bathrooms and laugh at people like Firewolf who asked the sensible question at the beginning of this post.
Its so easy this fire safety mullarky!