REPORT OF MR. NELSON L. DERBY.
387
enable all persons dwelling in them to pass readily out of doors.
5. When a stairway is lighted by means of a skylight, the frame of the latter must be constructed entirely of iron, and rest, on all sides, on masonry rising above the roof.
6. All stairways and passages connected with them must have a fire-proof railing.
7. Woodwork must be removed from the interior surface of all flues by a thickness of at least six inches of masonry. The masonry of the chimneys must be plastered on the exterior, from the pavement of the attic to the highest point of the roof.
8. Each story shall be provided with at least one separate flue, passing, without communication with any other, to its exit at the roof. Where the beams of the floors rest upon the walls containing flues, an earthen pipe shall be inserted into the latter, having, for its length at least, the thickness of the whole floor; and for its thickness, at least one inch. Every flue must have, at its commencement in the lower story, and also in the attic, a side opening, closed by two iron doors, closely shutting, and provided with a lock. Where several flues lie side by side, they shall be closed still further by an iron bar and padlock, extending over the openings of all. All woodwork in the vicinity of these doors must be covered with sheet-iron.
9. All roofs must be covered with tiles, slate, metal or some other fire-proof material. The woodwork of the roof must at no point be nearer than six inches to the pavement of the attic. Iron roof-frames must rest upon masonry alone; Wooden cornices are forbidden.
10. The attic roof must be covered with tiles, cement or other fire-proof material. An iron door, hung in an iron frame, must communicate alone from the main stairway with the attic. At least once, in every ninety feet of its length, the attic must be subdivided by a brick wall running across its width and rising nine inches above the roof. (This is generally covered above with zinc.) The compartments ensuing shall communicate with each other only by means of iron doors hung in iron frames. No dwelling-rooms are permitted in the attics of buildings.