The police in Wellington say initial tests indicate that powder mailed to Parliament Buildings on Wednesday is safe.
Three Beehive staff members and a Parliamentary Security officer suffered no ill-effects from the substance and the office space has been re-opened.
Detective Senior Sergeant Paul Borrell says tests on the powder indicate it doesn't contain any chemicals.
Full testing will be finished in a few days.
Police are making no comment on the origin of the envelope containing the powder.
