Whenever the commissioner, after any place of employment subject to this chapter shall have been inspected in accordance with N.H. Rev. Stat. § 277:13, shall be of the opinion that the special conditions in that place of employment render the standards inadequate or unreasonable, as applied to such place of employment, he may, by special order applicable to that place, so modify or extend the requirements of such standards as to make the same adequate and reasonable with respect to such special conditions.