Fire Alarm Design Types of Coverage: M, L1, L2, L3, L4 & L5 Systems 

Thank you for saying so, it’s been a few years since I made that video and I’m pleased to see it’s still relevant today.

I’m glad to hear that it’s helped you and thank you for taking the time to comment.

Glad you enjoyed it

Thank you for your comment Daniel, we’re more than happy to help defining fire alarm design types L1, L2, L3, L4 & L5

Hi, the 'D' stands for domestic and is only used on non-commercial systems [or detectors], the British Standard for this is BS5839-6 and this is for domestic premises. It [BS5839-6] is a very wide ranging standard and covers the cheaper domestic detectors you can buy off the shelf in B&Q, right through to systems that you would normally find in a commercial premises like and office or factory.

These fire alarm detection levels still apply, thank you for asking!

Hi Mike, There isn't a category of fire alarm called 'L1X' or similar. What's the context of this so we can try to determine what you need help with?/Where did you hear this? Kind regards, Verity Head of Comms at WFP