big, great, major, real, serious
constant
possible, potential
hidden, unexpected, unseen
environmental, industrial, natural, occupational
industrial hazards such as excessive noise and pollution
Loneliness is one of the occupational hazards of being a writer.

health
Other people's smoke is now seen as a health hazard.

fire
Those piles of newspapers are a serious fire hazard.

cause, create, pose, present
Production of these chemicals poses serious environmental hazards.

be exposed to, encounter, face
The worst hazard we faced was having our money stolen.

avoid
Go in September if you want to avoid the hazard of extreme heat.

eliminate, minimize
cope with, deal with, negotiate (esp. BrE)
Companies should have systems for dealing with work hazards.

hazard for
Stairs are a hazard for young children.

hazard to
The burning of industrial waste is a major hazard to human health.

exposure to a hazard
Try and reduce your exposure to hazards such as poor quality air.

Hazard is used with these nouns as the object:
guess