The protesters - Kristy Algar and Kevin Vaughan - used arm locks to connect themselves together in the foyer of STT allegedly limiting access to the site, while other protesters gathered outside with a pile of forest debris.

They were in place before 9am, and resulted in all staff within STT exiting the building on Bathurst Street via a fire escape.

Loud chainsaw sounds were also allegedly played through the offices, resulting in Ms Algar being charged with causing an unlawful environmental nuisance by noise emission.

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Tasmania Police used equipment to detach the arm locks about midday. Arm locks are a commonly-used device in BBF protests and police have protocols in place to safely remove them.

BBF campaign manager Jenny Weber said the protest came as STT prepared to undertake its annual post-harvest burning season.

"Using the terrified cries of the wildlife being crushed and burned we are using loud sounds in the offices to remind those overseeing the logging that native forest destruction is wildlife and climate destruction," she said.

A BBF spokesperson said the protest was carried out using "non-violence" principles, and did not restrict access to other offices in the building which includes a disability support organisation.

Recent BBF protests have centred on native forest harvesting plans in Wentworth Hills. A protester was also fined $500 this week over a protest targeting MMG in takayna/Tarkine.

Last month, 38 protesters had their charges dropped in relation to a protest against MMG's planned tailings dam, due to it occurring on a public road which STT did not have the authority to close.

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Forestry Tasmania head offices have been targeted with protest in the past.

STT chief executive officer Steve Whiteley said he condemned the protest in their Hobart offices.

"Today, the Bob Brown Foundation attempted to bully and intimidate STT staff in their workplace," he said.

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"This behaviour was undertaken with the clear objective to cause distress and harmful impact to staff and others. Bullying and intimidation is never OK."

Resources Minister Guy Barnett said the protest was a "workplace invasion" and the government would seek to introduce anti-protest legislation, which he urged Labor to support. In Parliament, Labor members said there was no legislation for them to actually support at this stage.

The Tasmanian Greens have previously voiced concern that the government and Labor could do a deal over the anti-protest laws, similar to last year's gaming legislation, given their major party majority in the upper house.

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