BS 5395-1:2010 pdf download – Stairs – Part 1 : Code of practice for the design of stairs with straight flights and winders
4.1 Handrails COMMENTARYON
4.1 Use ofa suitablydesigned handrail can prevent users from losing their balance when on the stair and can also assist users to ascend bypulling themselves up the stairs. A handrail can also help users to regain balance in the event ofa fall, reducing the severityofthe injuries that might result. The need for a handrail on both sides ofthe stair comes from two sources. Firstly, to allowusers a choice ofsupport when ascending and descending stairs, it is preferable to have a handrail on both sides. This can be essential for people using a walking stick or cane, or who might be weaker on one side. The other reason is that having two handrails reduces the chances of a serious incident happening on a stair. Every stair should have two continuous handrails, one on each side of the stair, to provide guidance and support to those using the stair. It is advantageous to many stair users to be able to reach either handrail or both handrails at the same time in which case, the distance between the handrails should be between 800 mm and 1 200 mm. Handrails should:
a) be fixed at a vertical height to the top of the handrail above the pitch line between 900 mm to 1 000 mm;
b) continue across intermediate landings at a vertical height to the top of the handrail above the landing between 900 mm to 1 100 mm where this is practicable e.g. not across doorways or obstructing adjacent circulation routes;
c) be fixed parallel to the pitch line over steps, or horizontal over landings;
d) be rigid and strong enough to provide adequate support for users;
e) be comfortable to grip and without sharp arrises, yet able to provide adequate resistance to hand slippage;
f) allow the entire hand to form a grip around the handrail, rather than a less secure pinch grip which uses just the fingers. This requires a clear mounting distance between the bottom of the handrail and the top of the stair balustrade of at least 50 mm; g) be continuously graspable along their entire length. Handrail brackets or balusters attached to the bottom surface of the handrail are not considered to be obstructions to a person’s grip, provided that they do not project horizontally beyond the sides of the handrail within 50 mm of the bottom of the handrail;
h) be a poor conductor of heat, if exposure to heat or temperatures below 0°C is likely. NOTE 1 Ideallythe maximum value ofthermal conductivityfor a material to act as handrails is 10 W/mK, with a preference for values below1 W/mK;
i) extend at least 300 mm on plan beyond the top and bottom nosing of a flight or flights of steps, providing it does not project into an access route.
j) be finished so as to provide visual contrast with the surroundings against which it is seen. NOTE2 Advice on visualcontrastcan be foundin BS8300:2009, AnnexB.
The handrail height on both sides of the flight should be identical. Where a handrail forms the top element of a stair balustrade (guarding top-rail), the handrail should continue to slope until the vertical height to the top of the handrail matches the height of the guarding top-rail above the top landing within the range given in 4.1b).
NOTE 3 Ideally, the handrail becomes horizontal directly above the bottom nosing, which can be achieved byadjusting the height ofthe handrail above the pitch line, within the range given in 4.1a). Where the guarding height in 4.2.1 is higher than the range specified in 4.1a) or 4.1b) or where the handrail does not form the guarding top-rail, the vertical height to the top of the handrail above the top landing should be equal to the mounting height above the pitch line over the flight within the range specified in 4.1a). The handrail should continue to slope for a depth of one tread beyond the bottom riser so that the handrail height above the landing is the same as it is above all step nosings.
The handrails should be free from any obstruction throughout a flight and continuous throughout the stair. Where a handrail is present over a winder fight, it should remain continuous, positioned 900 mm to 1 000 mm above the pitch line over the whole winder flight.
NOTE 4 For private stairs the outside handrail can be discontinuous, such that the handrail is not present over the winders. An outside handrail on winders that is equallydistant from the walking line is preferred to one that extends into the corner.
NOTE 5 Newels at the top or bottom ofa flight or on winders are not considered to be an obstruction provided that theyare finished with a graspable newel cap.