Here are the possible solutions for what a firefighter might leave footprints in clue
Answer
Clue
Relevancy
ash
Clue
What a firefighter might leave footprints in
Definition
the dust or remains of anything burnt
greenhousegases
Clue
They leave carbon footprints
carpetpeeves
Clue
Muddy footprints, worn patches, cat hair, etc.?
clues
Clue
Footprints, bloodstains, etc.
Definition
CLUE, to obtain guiding information
ecotourist
Clue
Visitor careful with footprints
Definition
a tourist who visits areas of ecological interest (typically exotic and often threatened natural environments), esp. to help conservation efforts and observe wildlife
heelmarks
Clue
Parts of footprints
holmes
Clue
To whom Mortimer declares "They were the footprints of a gigantic hound!"
