Chapter 9: Barrier-Free Design Flashcards
Which part of the ADA most affects designers?
Title III, Public Accommodations and Commercial Facilities
What is the full name of the current ADA guidelines?
2004 Americans with Disabilities Act and Architectural Barriers Act Accessibility Guidelines (ADA/ABA Guidelines)
What are scoping provisions?
To account for any differences between codes and standards, scoping provisions dictate how many accessible elements must be provided.
What is the section of the IBC that addresses accessibility?
ICC A117.1, Accessible and Usable Buildings and Facilities
How are the ADA/ABA Guildines organized?
They’re organized by a numbering system consisting of three parts:
1st - deals with ADA application and scoping requirements
2nd - covers ABA application and scoping requirements
3rd - gives the technical requirements intended to be used by both the ADA and ABA
What is an accessible route?
A continuous, unobstructed path connecting all accessible elements and spaces in a building or facility. Includes corridors, doorways, floors, ramps, elevators, lifts, and clear floor space at fixtures.
Minimum clear width for an accessible route
36” continuously
32” at passage point
Maximum length of passage point
24”
Minimum passage width for two wheelchairs
60”
What do you do if an accessible route is less than 60”?
Passing spaces at least 60”x60” must be provided at intervals not to exceed 200’
Minimum clear floor space to accommodate 1 stationary wheelchair
30”x48”
Minimum space required for a wheelchair to make a 180 turn
60” diameter
Maximum slope for accessible route
1:20 / 5%
Minimum clear width of door
32”
Maximum vertical change in elevation at threshold
1/4”
Minimum clear width for T-shaped space for 180 turns
36”
Minimum dimensions for turning in corridors or around obstructions
If obstruction is <48”: 42” clear on approach, 48” on turn
If obstruction is >48”: 36” clear on approach, 36” on turn
How do you treat elevations between 1/4 and 1/2”
- Must be beveled
- No part of threshold slopes more than 1 vertical unit for each 2 horizontal unit (1:2 slope)
- Any vertical change over 1/2” must comply with ramp specifications
Door operating device options
- Lever handle
- Push-type mechanisms
- U-shaped handles
Opening force required to push or pull open an interior door
Cannot be more than 5 ft-lbf.
Front approaching doors - minimum clear space in front of pull side
60”
Front approaching doors - minimum clear space in front of push side
48”
Front approaching doors - minimum clear space to side of latch on pull side
18”
Front approaching doors - minimum clear space to side of latch on push side
12”
Hinge side approaching doors - minimum clear space in front of pull side
If clear space to side of latch= 36”, clear space in front of door must be 60”
If clear space to side of latch=42”, clear space in front of door must be 54”
Hinge side approaching doors - clear space in front of push side door
y=42”
x=54”
Latch side approaching doors - clear space in front of door on pull side
48”
Latch side approaching doors - clear space to side of latch on pull side
24”
Latch side approaching doors - clear space in front of door on push side
42”
Latch side approaching doors - clear space to side of latch on push side
24”
Clearance between double doors
48”
Mounting height of grab bars in toilet compartments
33”-36” AFF
Minimum clear opening of toilet door
32”
Grab bar dims in toilet compartment
Back wall: 36” long; mounted 6” from side wall
Side wall: 42” long; mounted 12” from back wall
Clear floor space from toilet back wall for wall-mounted wc
56”
Clear floor space from toilet back wall for floor-mounted wc
59”
Centerline of toilet from wall
16-18”
Ambulatory compartment requirements
- 42” grab bars on both sides
- Centerline of toilet 17-19”
- 60” min. compartment depth
- 35”-37” compartment width
Urinal elongated rim max height
17”
Clearance between urinal shields
29”
What types of faucets are acceptable?
Must be operable with one hand, cannot require right grasping, pinching, or twisting of the wrist. Lever operated, push-type, and automatically controlled mechanisms are acceptable.
Mirror mounting height above lavatories or countertops
Bottom edge of the reflecting surface no higher than 40”
Mirror mounting height generally
Bottom edge no higher than 35”
Max height of lavatory
34”
Toe clearance under lavatory
9”H min; 6”D max
Minimum lavatory depth
17”
Min. knee clearance for lavatory
8”
Clear floor space for bathtubs
Side approach, seat in tub: 30”xlength of tub
Front approach, seat in tub: 48”x60”
Seat at head of tub: 30”x length of tub+12”
Maximum pile height of carpet
1/2”
Max slope for ramp
1:12 (1” of rise for every 12” of run)
Maximum rise for any ramp
30”
Exception to max slope for ramp
1: 10 is permitted if the max rise does not exceed 6”
1: 8 slope is permitted if max rise does not exceed 3”
Min clear width of ramp
36”
If ramps change direction at a landing, how big should should the landing be
60” squared
When are handrails required for ramps
Ramps with rises greater than 6”; lengths greater than 72”
Handrail extension beyond top and bottom of ramp segment
12”
Handrail gripping surface for ramp
1 1/4” to 1 1/2”
Maximum riser height and tread riser to riser length
7”; 11”
Stair nosing requirements
1 1/2” max depth; 60 degree radius
Stair handrail gripping surface
1 1/4”-2” diameter
or
Perimeter 4”-6 1/4” and max cross section dim of 2 1/4”
Egress stairway clear width
48”
Clear space between handrail and wall
1 1/2”
Protruding object requirements
4” max depth if >27” AFF
Larger objects must be >80” AFF
What is a detectable warning?
A surface feature built in or applied to walking surfaces or other elements to warn of hazards on a circulation path. ie. 0.2” high truncated domes spaced between 1.6”-2.4” on center in a square grid pattern.
Where are detectable warnings required?
Passenger transit platform edges where there is no guard or other protective elements; other placement depends on local code
Audible alarm sound requirement
Exceed prevailing sound level in room by 15 dB
ADA lettering requirements
5/8” - 2” depending on viewing distance
Uppercase
Sans serif typeface
Grade 2 Braille
ADA sign requirements
Eggshell, matte or non-glare finish
Characters contrasting with background
Elevator requirements interior designers need to know
Call button and floor buttons no higher than 48” AFF
How much accessible seating is required for built-in/fixed seating in public or common-use areas?
5% but not less than 1 table
Should be dispersed around facility
Minimum number of wheelchair locations for places of assembly?
At least 1% must be aisle seats with no armrests on the aisle side or must have removable or folding armrests on the aisle side.
