SLIP AND FALL
Charles C. Roberts, Jr.
Slippery surfaces, improper footwear, inadequate hazard identification,
insufficient training, inattentiveness, construction deficiencies, claimant
physiology and fraud are among the many underlying reasons for slip and fall
claims against home and industrial property owners. The classic slip and fall
claim alleges building related deficiencies that caused the slip or fall. The claims
professional is faced with the examination of the premises and the determination
as to the validity of the claim. To initiate the investigation, analysis of the
premises is a cost-effective first step. Measurements of critical dimensions,
frictional aspects of the stairs or floors and lighting levels, yield factual
information that acts as a basis for accepting or denying a claim. Three major
ingredients of the slip and fall accident revolve around the friction between the
floor and the claimant’s shoe, physical configuration of the accident scene, and/or
lighting of the scene. The following delves into the intricacies of each.
It is generally considered in the industry that a walkway surface with a coefficient
of friction higher than 0.5 is non-hazardous. (Ref 1). Federal regulations from the
Americans with Disabilities Act recommend a coefficient of friction of 0.6 or
higher. The coefficient of friction is a measure of the slipperiness of a surface.
The lower the coefficient, the more slippery the surface. For instance, rubber on
ice has a coefficient of friction around 0.06. The coefficient of friction for rubber
on asphalt is approximately 0.6. Therefore, ice is about 10 times slipperier than
asphalt. The coefficient of friction is the ratio of the weight of an object to the
frictional force required to just move the object. If a block of concrete weighing
40 lbs. requires 20 lbs. to just start moving on a floor, the coefficient of friction is
20/40 or 0.5.
If a claim of a slippery surface arises, determination of the coefficient of friction
through testing may help in the evaluation of the claim. Figure 1 is a view of a
testing device called a slip meter. The slip meter measures the coefficient of static
friction. The technician pulls on the meter with a string until the meter moves.
The coefficient of friction is read directly on the meter. In Figure 1, the meter is
being calibrated on a standard piece of tile. Once calibration is verified, the meter
is placed on the floor to be measured, as shown in Figure 2. Three readings are
made and averaged. The average coefficient of friction is compared to the
particular standard being used, such as 0.5. If the readings are below 0.5, then the
likelihood of a slippery surface having caused the accident has increased. If the
coefficient of friction is greater than 0.5, then it is unlikely that a slippery surface
is the cause of the accident. Figure 3 shows a test of a dance floor where a slip
and fall accident occurred. The waxed floor had a coefficient of friction of
between 0.6 to 0.7, which is acceptable. Some of the dancers would sprinkle
“dance powder” under their tables and work the powder into their shoes. This is to
aid in the sliding motion associated with dancing. The dance powder reduced the
floor coefficient of friction to the range of 0.25 to 0.35, which is below the slip
resistant range of 0.5, or greater, as defined in Reference 1. It is likely that the
excessive use of the dance powder contributed to the slip and fall accident on the
Slip and fall accidents often occur on stairs. Typical causes of accidents on stairs
are slippery surfaces, stair construction or design deficiencies, poor lighting,
obstructions on the stairs and inattentiveness. Reviews of human factors and
architectural literature reveal that the optimum slope of a stairway for general
purposes is approximately 30 degrees. This translates to a tread width of 11 inches
and a riser height of about 6.5 inches (Figure 4). Reference 2 requires a minimum
tread of 9 inches and maximum riser of 8.25 inches for single family dwellings.
Many claims allege that the stairway was deficient and did not conform to code.
In this case, dimensional measurement of the stairs is necessary to compare with
building code requirements. Figure 4 shows a preferred stair design with smooth
rounded nosing. A less preferred design is shown in Figure 5 where the abrupt
transition from riser to nosing can increase the chance of tripping while ascending
the stairs. Many older buildings, along with some new ones, have this type of stair
design. Although not forbidden by code, the abrupt transition design is less
desirable. Handrails are often required by code for stairways. Typically handrails
should be between 30 and 34 inches above the nosing of the treads.
Often, slip and fall claims involve poor lighting. Local building codes require a
minimum lighting level often specified in foot-candles. For instance, the lighting
level for a stairway should not be less than 3 foot candles at floor level as
indicated in Reference 2. To verify the lighting condition at the accident scene,
testing can be accomplished easily using a variety of meters as shown in Figure 6.
Each of the meters is portable and displays the lighting level in an analog or
digital readout. It is desirable to replicate the lighting conditions to match those at
the time of the accident before taking a reading.
The above mentioned tests will reveal any deficiencies with respect to building
construction that could have caused or contributed to the accident. If no
deficiencies were found, analysis of medical records may be helpful. If the
claimant was elderly, the fall may be a result of bone thinning (osteoporosis)
rather than a deficiency in the building construction. Biomechanical analysis of
bone fractures (see Claims, August 1994) may reveal a fracture mode that is not
consistent with the accident scenario, which may be fraudulent. Chemical usage at
the time of the accident may be significant. Finally, if the accident scene is found
to be hazardous, were sufficient warnings posted.
1. ASTM D2047-93, “Standard Test Method for Static Coefficient of Friction of
Polish-Coated Surfaces as Measured by the James Machine”, American
Society For Testing & Materials, West Conshohocken, Pennsylvania, 1993
2. BOCA Basic Building Code, Building Officials & Code Administrators
International, Inc., Homewood, IL.
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