Manhole steps.  Part 1,  Specification for galvanized ferrous or stainless steel manhole steps / 
British Standards Institution. 
 - 1 volume :  illustrations ;  30cm. 
 - British standard ;  BS 1247 : Part 1 : 1990 .
 - British standard ;  BS 1247 : Part 1 : 1990 .
<br/><br/><label>Subjects--Topical Terms: </label><br/>Manholes--Standards.<br/>Sewerage--Standards.<br/>Stair building--Standards.