The 36-hectare grass and scrub fire was reported at 4.58pm on Thursday and was controlled by yesterday afternoon.

The blaze was east of the Bell Bay industrial site, near the East Tamar Highway.

Acting North-East district officer Brett Fazackerley, of the Tasmania Fire Service, said the fire started when winds up to 90km/h caused powerlines to arc.

Dry grass beneath the lines caught on fire and the blaze spread into rocky scrub country.

Almost 40 firefighters and half a dozen firefighting appliances fought against the blaze, as well as two helicopters.

Crews will continue to patrol the site. Mr Fazackerley praised the tremendous job done by all, including volunteer firefighters who worked overnight between Thursday and yesterday.

He said no assets were lost, but firefighters were alert to the risk of the 110,000-volt transmission lines overhead.

Train lines were closed as a precaution, but reopened yesterday morning.

"Everyone did an outstanding job in very rough terrain and harsh conditions, with winds up to 90 km/h making firefighting very difficult," Mr Fazackerley said.

"They did a really good job to keep the fire within the boundary we put in.

"There's a good, solid line around it now. We hope that we have done all the work we need to do. Just the weather, if it eases, will put the fire out."