Distribution of Liability Claims (Percentage of claims paid by US parking operator) Data from claims to a national parking operator over four months, Source: Monahan, Donald R “Safety Considerations in Parking Facilities” The Parking Professional, September 1995 Nearly ¾! Probably doesn’t include fender benders; most paid by auto insurance. These are mostly valet damage claims.
Pre-collision Actions (Percent of incidents) Box, Paul, “Parking Lot Accident Characteristics” ITE Journal Dec 1981 Parking and unparking comprise 2/3!
More info from Box Article Accidents reported to Naperville IL Police Data base of 825 accidents over three years (1978-80) in facilities with 15,850 parking spaces. 24 accidents with injuries (3%) Moving vehicles striking moving vehicles comprised 29% of all accidents, but just over half (13/24) of accidents with injury Of 24 accidents with injury: 6 occurred at aisle intersections 5 veh hit pedestrian (0.6% of all accidents, 21% of those with injuries) 5 occurred when moving vehicle struck fixed object (1 was a curb!) 3 one vehicle cut across parking rows 2 vehicle backed out of stall into path of other 2 sideswipe (both vehicles driving forward) 1 vehicle driving down aisle struck parked vehicle
Collisions in parking facilities (Percent of incidents) 1996 Data Source: Safety Design Guidelines in Parking Facilities, First edition, Vancouver: Insurance Corporation of British Columbia, Sept 1998 Very similar to Box study; accounts for 20% of injuries
Benefit of Liability Claims Data Even if lawsuits are not a direct concern (e.g. in less litigious countries) the data shows WHAT CAUSES SERIOUS INJURIES in parking facilities
ASTM Standard F1637 Safe Pedestrian Walking Surfaces, Summary: Illuminance per IESNA (latest edition) Walking surfaces shall be slip resistant, including pavement markings where wet conditions reasonably anticipated. Changes in level: same as in ADAAG (even where not an accessible route) ¼” max vertical edge, beveled ¼ to ½”, No edges >1/2” Avoid wheel stops; where necessary, center in stall, min 3’ clear between ends (for 8’6” stall, that mean 5’6” max long) Avoid speed bumps IBC prohibits speed bumps in parking facilities If required, use speed humps, paint (with slip resistance) and add pedestrian warning signs
In addition to ASTM IBC, and ADAAG stds, most consultants recommend: Wherever possible, use following to direct/control traffic* or separate vehicles from peds: Bollards Pipe guards Flexible delineators Provide curbs/wheel stops only where no alternative to protect Buildings Landscaping (surface lots, green roofs etc) Connections (precast spandrel panels) Equipment If pedestrians might conceivably cross a necessary curb, paint yellow on vertical face and 6” horizontal Not needed at perimeter where peds wouldn’t typically go across curb *Including preventing vehicles driving across parking lots….
Slippery Floor Surfaces 57% of claims from slip and fall. Various floor surfaces (concrete, asphalt, coatings, snow, ice, water). Current codes (including ADA, IBC and OSHA) do not have a required minimum for coefficient of friction and/or slip resistance. Recommendations are provided, but no recognized testing method is available. Proper drainage, even where covered and rain is rare Traffic toppings/coatings loose their abrasion resistance (sand) over time and must be recoated. Stair treads have little surface area for foot and need to be slip resistant. Consider adding abrasive nosings, if necessary. Use glass beads or sand at large painted floor markings (turn arrows, stop bars, etc).
Curbs of any type CAUSE INJURIES and should be avoided in parking. More liability claims in US for slips/trips and falls in parking than any other issue; 73% of claims in one study People are more likely to be injured by trips/slips and falls than by fender benders from people driving across parking lots. New ASTM standard (2002, reissued in 2009) for safe walking surfaces recommends against wheel stops and curbs It was “on radar” of ASTM to do requirements for parking areas! Even though not (yet) incorporated by reference in building codes, ASTM standard will be used by plaintiffs in lawsuits. Wheel stops also make it difficult to clean parking areas, collect refuse, etc. Wheel stops are not effective at assisting drivers to park properly in stalls. Wheel stops are difficult to secure, and damage the concrete over time.
Curbs/wheel stops can be trip hazards Unpainted wheel stops used, off- centered. While some curbs beyond are painted, they still can cause trip hazards Wheel stops in this position are even more likely to result in trips and falls than when stop is centered in stall More importantly note how difficult it is to see wheel stop when concrete on concrete.
Curb intended “to protect” elevator waiting area, added railings (reportedly) after trip and fall Bollards instead of curbs would be better!
Use bollards to separate pedestrians from vehicles instead of curbs
Use paint, bollards and pipe guards to direct traffic; use curbs only where necessary No curb on ramp edge; yellow- painted, concrete- filled post protects pipe Note: equipment islands are absolute minimum required, with extra posts for further protection of equipment. Curb is for setting equipment No curb between traffic flow in opposite directions on ramps (except where required to prohibit turns)
Paint necessary curbs yellow where peds might conceivably cross in path to/from destination Curbs at tower painted traffic yellow Wheel stops didn’t protect these signs! Instead of wheel stops, put accessible sign in concrete-filled steel post, painted traffic yellow, centered on stall, out of ped path. Note difficulty seeing wheel stops away from light fixtures on asphalt too
Where curbs required, hold curbs back 10” min, 12” preferred, from nominal stall line Minimizes risk of somebody stepping out of car onto curb or tripping over it. Also gives same comfort of turning movement into stall as other stalls.
More info against wheel stops and curbs If concerned about “cross country” driving, break into smaller sections with long islands, heavily landscaped to help pedestrians realize it is not a ped path. Use islands instead of wheel stops because difficult and expensive to clean behind wheel stops. Mechanical sweepers and/or snow removal equipment cannot access. Significant because regular maintenance and cleaning of floor areas are critical to durability. Curbs are NOT adequate to control lot perimeters for revenue control Curbs are NOT adequate to meet code required vehicular impact loads None of the usual connection methods of wheelstops are desirable. Stops epoxied to floor may be knocked loose often taking some surface with it. If the wheel stop is bolted or otherwise mechanically anchored, even small but repeated impact loadings can damage paving around anchor. Creates path for water penetration into concrete (and corrosion) or into base under asphalt. Damaged surface can also be an additional tripping hazard
Wheel stops do not significantly improve parking position in stalls Low profile vehicles stop short. If placed far enough to protect element from maximum vehicular overhang, cause vast majority of cars (which have less overhang) to park farther out towards aisle. Useless for “Texas style” parking. If knocked loose, causes yet more problems parking in stalls Therefore wheel stops and curbs have more negative than positive benefits.
Therefore: Provide curbs ONLY where required to protect: Landscaping Vulnerable construction Structural connections (e.g. spandrel panels above grade) Where required for above, and where pedestrians might foreseeable (wisely or not) try to walk across, paint vertical face and 6” at edge along top TRAFFIC YELLOW Eliminate wheelstops Lighting to meet IESNA (latest edition) Calculate illumination at END of rated bulb life Most owners don’t relamp until burn out