High levels of clutter make it much easier for a fire to start and create a greater risk of fire spreading, increasing the risk of injury and death.
It can also makes it very difficult to escape and can lead to difficulties for firefighters tackling the blaze.
To consistently identify the level of hoarding in homes across London, our fire crews use the International OCD Foundations clutter image rating.
The images above show the same room with clutter ratings one, four and nine - between one to four is normal; five and nine is cause for concern.
We’re asking for people with hoarding tendencies; their friends and family to get in contact and arrange a free home fire safety visit.
The visit will give firefighters a chance to work with a person who might have a dangerous amount of clutter in their home and make sure they know what to do if there is a fire and how to escape.
Get more information on fire safety at home, at work or in you community.