you are likely to find Noise in/at/on Transmission. Noise is related to Ear. Ear is related to Mouth. 
Flood is a type of Cover. Flood is related to Emergency. Emergency is a synonym of Casualty. 
Transmission <--AtLocation-- Noise <--RelatedTo--> Ear <--RelatedTo--> Mouth 
Cover <--IsA-- Flood <--RelatedTo--> Emergency <--Synonym--> Casualty 