S3.11 – S3.17SRISERS AND NOSINGSS3.11*A stair serving a storey to which access for disabled people is required by S2.6 must have -a. risers profiled to minimise tripping; andb. nosings distinguishable through contrasting colour or tone.Note:This standard does not apply to a private stair in a dwelling.FLIGHTS CONSISTING PARTLY OF STRAIGHT AND PARTLY OF TAPERED TREADSS3.12*In that part of a flight consisting of tapered treads, the going of the tapered treads must be uniform andmust not be less than the going of the straight treads. At the inner end of the tread the going must be atleast 50mm.S3.13 In a flight less than 1 metre wide the going must be measured at the centre line of the flight as in S3.2.S3.14 In a flight 1 metre wide or more the going must be measured at the two points 270mm from each end ofthe tread as in S3.2 and the minimum going must be at least the going of the straight treads.FLIGHTS CONSISTING WHOLLY OF TAPERED TREADSS3.15*A flight consisting wholly of tapered treads must be constructed so as to give safe passage. Therequirements in S3.18 to S3.25 for landings, so far as they apply to intermediate landings betweenfloors, and for handrails, and for headroom, do not apply to such stairs.PEDESTRIAN RAMPSS3.16 The maximum gradient and maximum length of a flight of a ramp for use by pedestrians must be inaccordance with the table to this standard -Table to S3.16:Gradient and length of a flight in a rampGradient of flight Maximum length of flightnot more than 1 in 20No limitnot more than 1 in 1510mnot more than 1 in 125mmore than 1 in 12not permittedS3.17 A ramp must have -a.a width at least the minimum required for the equivalent type of stair in S3.4; andb.a raised kerb at least 100mm high on any exposed side of a flight or landing,except -a ramp serving a single dwelling.Amdt: December 1999 13S