In the most common handrail installation, the handrail balustrades are fixed on top of the stair surface but is there any restriction from NFPA 101 to fix the handrail balustrade on side of stair flight? Thank you in advance.
No- the Code sets a performance criterion that permits alternative solutions. See Subsection 220.127.116.11.6.3 of the Code.
subsection 18.104.22.168.6.3 for guard details and is talking about the intermediate rails and an ornamental pattern but nothing mentioned about the proper balustrade fixation whether it shall be on top of the stair surface or on side wall mounted.
In my opening sidewall balustrade fixation could cause some inconvenience to the people during using the stair due to the gap between the handrail and stair flight.
The handbook indicates some pictures showing the handrail posture on top of the spiral stair surface but I can't find the same on the regular stair.
As previous said, the Life Safety Code (LSC) sets a performance criterion that permits alternative solutions. I could just image how many ways that stairs can be designed and installed and then list Code requirements for each possible way. The photos and illustrations in the LSC handbook are not the Code requirements or a design manual, but they are used to help with the intent of the Code.
In the spirit of the LSC, a balustrade is a guard for open sides of the stairs to help prevent a fall over an open side. The opening dimensions in the guard includes preventing children from falling over an open side. The LSC allows stair and ramp handrails to be separate or to be integrated with the guards. The occupant must be capable of reaching the handrail in the position it was installed.
Here is the performance criteria I would use when reviewing your plans:
22.214.171.124.5.7 New handrails shall be continuously graspable along their entire length.
Where the balusters support the handrail, the hand should be able to slide along the handrail without encounteringobstructions that would require the release of the hand’s grip.
126.96.36.199.5.8 Handrail brackets or balusters attached to the bottom surface of the handrail shall not be considered to be obstructions to graspability, provided that both of the following criteria are met:
(1) They do not project horizontally beyond the sides of the handrail within 1 1 ⁄2 in. (38 mm) of the bottom of the handrail and provided that, for each additional 1 ⁄2 in. (13 mm) of handrail perimeter dimension greater than 4 in. (100 mm), the vertical clearance dimension of 1 1 ⁄2 in. (38 mm) is reduced by 1 ⁄8 in. (3.2 mm).
(2) They have edges with a radius of not less than 0.01 in. (0.25 mm).
Where handrails are supported by a balustrade, I would verify Subsection 188.8.131.52.1.2 horizontal location was met for natural path of travel. The handrail should be within the required egress width of the stair and allowed by the LSC to project 4 1/2 inches into the required egress width.
184.108.40.206.1.2 In addition to the handrails required at the sides of stairs by 220.127.116.11.1.1, both of the following provisions shall apply:
(1) For new stairs, handrails shall be provided within 30 in. (760 mm) of all portions of the required egress width.
(2) For existing stairs, handrails shall meet the following criteria:
(a) They shall be provided within 44 in. (1120 mm) of all portions of the required egress width.
(b) Such stairs shall not have their egress capacity adjusted to a higher occupant load than permitted by the capacity factor in Table 18.104.22.168 if the stair’s clear width between handrails exceeds 60 in. (1525 mm)
I would verify the required egress width of the stairs in accordance with Subsection 7.3.2 and verify the handrail was within that width.
7.3.2 Measurement of Means of Egress.
22.214.171.124 The width of means of egress shall be measured in the clear at the narrowest point of the egress component under consideration, unless otherwise provided in 126.96.36.199 or 188.8.131.52.
184.108.40.206 Projections within the means of egress of not more than 4 1 ⁄2 in. (114 mm) on each side shall be permitted at a height of 38 in. (965 mm) and below. In the case of stair and landing handrails forming part of a guard, in accordance with 220.127.116.11.5.3, such projections shall be permitted at a height of 42 in. (1065 mm) and below.
18.104.22.168 In health care and ambulatory health care occupancies, projections shall be permitted in corridors in accordance with Chapters 18 through 21.
In conclusion, your information gives the impression of the handrail not being located inside (within) the required egress width in accordance with 22.214.171.124.1.2.
Retrieving data ...