As problem solvers, we tend to get way ahead of ourselves. We tend to go for solutions before we totally understand the causes, problems and the systems in which they exist.
This is the problem when we seek to solve slip, trip and fall injuries. Some of our roadblocks come from the paradigm that solving these injuries is easy. Posting signs, quickly cleaning up messes, telling employees to be more careful or specifying safety shoe soles to wear, commonly is our easy way to deal with these problems, but all are totally ineffective solutions.
Perhaps our desire to make slip, trip and fall injuries go away is rooted in our propensity to grab for quick solutions when we don’t understand what the many causes and factors are and what we are trying to improve. slip, trip and fall injuries go away is rooted in our propensity to grab for quick solutions when we don’t understand what the many causes and factors are and what we are trying to improve.
So, let’s take a deeper look at the causes and factors of slip, trip and fall injuries. Taking this “mile-deep-and-inch-wide” look will help us see why adopting new rules for effectively preventing these injuries makes sense.
The static coefficient of friction (SCOF), or the measure of slip-resistance commonly is espoused as gospel but grossly misunderstood because we equate SCOF with a measure like handrail height or a PEL.
In reality, slip-resistance is highly variable both by how it is measured (if there is a need to measure it) and what truly is safe or unsafe because our lines for determining safe slip-resistance are anything but bright.
Let’s talk about slip-resistance testing first. Factually, there is no clear testing method for slip-resistance. The English tribometer is thought by a lot of floor safety experts to be the preferred method of testing for slip-resistance, but the drag or pull meter, as an example, widely is used and gives good results.
The important thing for us to understand is that the variation in testing results of any slip-resistance testing methods is high, perhaps less with the drag meter, for example, because of the size of the floor area actually tested. The English tribometer, in its testing method, strikes the walking surface and each test or strike hits an area of about one square centimeter or less where a drag instrument tests an area around three square inches, depending on the meter used. So, variation in testing results can change by just moving the point tested a centimeter or inch.
Also consider that the line that is supposed to identify what is safe and unsafe is broad if you consider the commonly-accepted SCOF limit of 0.5 as the standard. This is why other countries and business sectors have adopted higher SCOF limits.
All other slip and trip system factors and interrelated issues must be taken into account, especially testing variation. So, this is why many slip experts have been moving away from espousing the importance of or from focusing on measures of slip-resistance as input into solving slip hazard problems.
As those who commonly are called on to say of something is hazardous or not, a murky line doesn’t help us. So, how can we resolve this conundrum?
If we get our heads out of the exactness, the dependence on measures and data, finding a bright line can be easy if we use a legal line, those regarding known hazardous conditions.
Let’s quickly identify some known hazardous slip conditions that really require no slip-resistance testing, as exactness isn’t helpful and only can add to the argument. Conditions that are known to be hazardous and thereby require correction and even more importantly, prevention include:
- Ice on any walking surface, especially black ice that cannot be easily seen
- Any lubricant or surfactant on a walking surface, regardless of the texture of that surface, that significantly reduces the slip-resistance;
- Water, or any liquid or fleshy material on a surface that is non-porous or sealed or polished, such as linoleum, marble, hardwood, ceramic tile or even highly smoothed and polished concrete;
- Wet materials that are transient in form like wet paint or remnants from cleaning up, mopping, etc. and
- Any industry- or process-specific material that is spilled and is known within the industry or business sector to be slick.
We as safety practitioners depend way too much on people seeing things as a means to preventing injury. So, understanding the mechanics of walking is extremely important for us and not just the muscle, momentum and balance mechanics, but more importantly first, the control mechanics of walking.
We commonly forget how we walk when we quickly try to problem-solve slip and fall injuries. It seems so obvious that people slip and trip when walking, yet we move to solving the problems before we understand the mechanics that contributed to the fall.