The latest four-day forecast shows the Northern Country forecast district can expect poor air quality on Monday, while the North Central and Central districts are likely to experience very poor air quality.

This is expected to improve slightly on Tuesday, but decline again on Wednesday.

EARLIER: Air quality in the Bendigo area is forecast to drop to very poor by Tuesday, as bushfire smoke continues to move across the state.

The Environment Protection Authority Victoria expects air quality in the Northern Country district will fall from good on Saturday to moderate on Sunday, before declining further to poor on Monday and very poor on Tuesday.

The Central and North Central districts are expected to experience good air quality on Sunday and moderate on Monday, before it too becomes very poor on Tuesday.

Related: City's air quality remains unmonitored despite warnings

The EPA advises people in smoke-affected areas to stay inside as much as possible, set air conditioners to recirculate, keep windows and doors closed, and reduce physical activity.

Ordinary paper masks do not filter out smoke particles; P2 and N95 masks do, but require a good seal for effectiveness and generally only work for about four hours.

Read more: Health warning as smoke haze hits Bendigo

People aged over 65 and 14 or younger, pregnant women, and people with existing heart and lung conditions, including asthma, are more susceptible to ill-effects of smoke.

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