Parking Lot Trip Hazards Expert Article

Parking lot safety can best be reliably established through proper design, construction, maintenance, and operations. This article discusses parking lot trip hazards, including a description of what constitutes a trip, relevant safety concepts, and links to other articles for more information.

Parking Lot Trip Hazards - Expert Article

What standards apply to parking lots?

In general, the paved surface within the perimeter of a parking lot should be treated as a potential walking surface, and for this reason parking lots are held to the same safety standards as other walkways

What causes trips?

A trip is caused by the disruption of the foot during the forward motion of the swing phase of the gait cycle. As humans walk, our foot is raised above the ground with a small clearance during its forward swing. If the forward motion of the leading foot is stopped mid-stride, the body continues forward and the center of gravity moves beyond its base of support, typically resulting in the loss of balance and a fall. Obstacles that interrupt the foot’s forward swing can cause a trip. Examples of trip hazards that are commonly encountered in parking lots include decayed and misaligned surfaces, irregular curbs, debris, wheel stops, and speed bumps. Though often related, the trip and the fall are two discrete concepts. [See Gait Analysis article]

Concepts relevant to parking lot pedestrian safety

Standards relevant to pedestrian safety generally call for walkways to be stable, planar, flush, and even to the extent possible. In this context, the last three terms are often used interchangeably.

• Stable – Flooring and walkways should generally resist movement when walked upon. Walking surfaces that move under normal use may result in a loss of balance. Examples of unstable walking surfaces include pavers that wobble, broken asphalt that rocks, and loose gravel that rolls underfoot.
• Planar / Flush / Even – Flooring and walkways should generally be free of raised or sunken irregularities with only gradual deviations moving across the surface. Objects that protrude from the surface and features that cause unexpected changes in surface height may cause trip incidents. These include items like drainage grates and utility access covers.

Real world conditions present practical limitations, so surface irregularities up to ¼” in height are considered acceptable. Research demonstrates that abrupt vertical edges greater than ¼” can create considerable risk for trip incidents and require remediation based on their size, profile and location.

How does perception and expectation affect parking lot safety?

Trips are more likely to occur when a pedestrian neither perceives nor expects to encounter trip hazards. Research has shown that when pedestrians anticipate a hazardous path, they will focus their attention toward the ground and navigate the walkway with care. However, when pedestrians do not expect hazards and fail to perceive them, due to inadequate lighting, lack of conspicuity, or other factors, trip and fall incidents are more likely to occur. Where hazards cannot be eliminated, visual cues such as contrast painting and warning signs can alert pedestrians to avoid the hazard.

How frequently should parking lots be maintained?

The safety of a property is addressed through two primary methods: preventive maintenance, and unplanned maintenance. [See Property Maintenance article]

• Preventive maintenance is based on scheduled maintenance of elements on a regular basis. By planning and scheduling the program properly, elements of the premises can remain safely in use without hazards. This type of maintenance is low-frequency, seasonal and in-depth.
• Unplanned maintenance is the everyday work that is done more frequently to identify and remediate hazards. This type of maintenance is custodial in nature and identifies changing conditions.

Preventive parking lot maintenance typically includes annual inspection, cleaning and crack sealing to help prevent damage caused by contaminants and standing water; periodic resealing and maintenance of lines and other surface features that are subject to wear and tear; along with unplanned maintenance of defects caused by severe weather, vehicle traffic, or other forces.

Parking lot trip hazards

Design and construction defects, maintenance deficiencies, and poor housekeeping practices can all increase the risk of pedestrian trip incidents. Parking lots are dynamic environments with numerous potential configurations that often include the components listed below. Our experts specializing in premises safety have addressed these topics in other substantive articles:

• Wheel stops - Also known as curb stops or parking blocks, wheel stops are the small barriers used at the head of parking spaces to prevent vehicular encroachment. These features, along with the hardware used to secure them to the pavement are consistently identified as pedestrian tripping hazards. [See Wheel Stop article]
• Curb Ramps – Pedestrian curb ramps become more prone to trip and fall incidents when they are constructed with side flares that are irregular, or steeper than permitted. Damage to detectable warning mats is another common cause of trip incidents. [See Curb Ramp article]
• Pavement Irregularities - Conditions such as rutting, shoving, or raveling can result in uneven and unstable walking surfaces and should be addressed through ongoing premises maintenance to prevent pedestrian injuries. [See Parking Lot Surfaces article]
• Sidewalks - Studies of pedestrian falls have identified that even small changes in elevation between sidewalk slabs are dangerous because of the low probability that pedestrians will reliably detect them. [See Sidewalk article]
• Low Rise Stairs - Single step transitions and short flight stairs have long been recognized as hazardous. Unless they are provided with safety features like handrails and visual cues to make them conspicuous to users, they are not readily identified, which can result in a loss of balance and fall. [See Short Flight Stairs article]

Parking Lot Injury Investigations

The Premises Safety experts at Robson Forensic are frequently retained to investigate cases involving slips, trips, and falls as they relate to parking lots, sidewalks, ramps, stairs and other architectural features. Our experts are well versed in the standards relevant to pedestrian safety and industry standards governing retail, residential, and commercial premises.

For more information submit an inquiry, or contact your local robson forensic office.