Specifications
The Ironped detectable warning plates shall be manufactured of ASTM A-48, Class 30 B Gray Iron. The casting shall be steel shot blasted and free of any adhering sand or debris.
The standard size is 24” x 24″. A lock slot and lug are for fastening two plates together with no special hardware required. Additionally, there is 24″ x 30″ size. Radius domes available upon request.
The minimum plate thickness shall be 5/16″ with a weight of 62 pounds for the 24″ x 24″ plate. The 24″ x 30″ plate weights 77 lbs.
The plates shall have 4 vent holes to allow entrapped air to escape during installation. These vent holes shall be countersunk to allow optional stainless steel countersunk flathead anchor screws to be inserted through the holes into the concrete below.
The top surface shall have truncated domes that meet the size and spacing as specified in ADA and ABA guidelines. The Plate surface and dome truncation surface shall have a tight pattern of raised conical points to increase the coefficient of friction.
Background
Detectable warning plates are widely used as a tactile warning for the blind in sidewalks, walkways and other similar structures. Typically, detectable warning plates are embedded in the sidewalk and have an upper surface with an arrangement of regularly-spaced protrusions in the shape of truncated domes
Hauger et al. (1994) obtained subjective data from 70 research participants who were blind or who had low vision, indicating that detectable warnings were judged to be helpful. In the same project, raters viewing videotapes of the 70 participants as they crossed intersections with and without detectable warnings on curb-ramps, found that a higher proportion of unsuccessful crossings occurred where there were no detectable warnings than where there were detectable warnings.
Service
Properties
- Excellent non-skid characteristics (0.90 coefficient of friction)
- Highly resistant to snowplow damage
- Excellent adhesive properties to concrete
- Attractive natural finish requires no maintenance
Optional powder-coated finishes: federal yellow, optical white, brick red
Installation Steps
- If additional coverage is needed, bolt Detectable Warning Plates together
Use supplied lifting springs and 2×4 lumber to lift plates
- Pour concrete
- Set plates in wet concrete at final position
- Remove lifting springs
- Press assembly into wet concrete to final elevation
Finish concrete around assembly
Note: Keep wet concrete off of the top surface of the plates at all times