A blast at the Khark petrochemical plant in southern Iran's Bushehr province on 24 July killed four people and injured seven.
The complex, which provides part of the province's electricity supply, caught fire as a result of high pressure in its central boiler, according to the IRNA news agency.
The situation is under control and the complex is closed for cleaning.
Khark petrochemical complex employs about 400 people and is located on an island in the Persian Gulf.
