I would like to export steel frames for construction to Japan. How do I have to do for production of steel accepted in Japan? 

Designated building materials stipulated in the Building Standards Law should be manufactured.

1. Building materials such as timber, steel materials and concrete utilized as essential parts of foundations and major structure of buildings from the viewpoints of safety, fire-proofing and sanitation should be "designated building materials" approved by the Minister of Construction (Article 37).

2. "Designated building materials" should conform with Japanese Industrial Standards (JIS) or Japanese Agricultural Standards (JAS) designated by the Ministry of Construction. You may obtain a certification that such materials conform to technical standards stipulated by the Minister of Construction.