Slip Resistance: Ending The Skids?

November 4, 2005

   Let’s put it this way, if someone falls on a floor you’re maintaining, you could be liable. So, yes, it really is that big of an issue for anyone in the stone industry.
   Perception is everything, and stone is perceived to be very slippery. However, things are not always as they seem, so let’s take a close look at how you may be able to change those perceptions.
   In the United States, the Americans with Disabilities Act (ADA) is often seen as the prime example of good intentions being the paving for the road to … well, let’s not get into that here. And, let’s not start by quoting, chapter and verse, the ADA section on slip resistance and Static Coefficient of Friction (SCOF).
   In the interests of clarity, here’s the Cliff Notes – or, more precisely, Tom’s Notes – version:
   • Basically, you need enough traction to not slip, and not too much to restrict natural movement.
   • When on an incline or slope, there must be enough traction so as not to slide down. (Were there really people out there designing buildings that caused people to slip all over the place?).
   • A floor must not make use of a wheelchair difficult, so shag carpets in public areas are a no-no (score one for the stone industry).
   • Cobblestone and irregular surface (lippage) is also to be avoided (score bonus points for floor-leveling restoration pros).
   They also list SCOF numbers of 0.6 for floors and 0.8 for ramps. Now to sound like Joe Pesci in Lethal Weapon 2, “OK, OK, OK, OK,…..OK. Just what do those numbers mean? OK?”
   SCOF values are measured by determining the amount of force required to create the movement of an object across a surface, using devices with names like the Horizontal Pull Sipmeter and The James Machine. The object is to drag an object lined with a material (designed to act as your shoe sole, such as leather, rubber or neolite) across the floor material to be tested in a controlled environment.
   The measurement of the force needed to initiate the movement is recorded, and this is the static coefficient of friction. It’s much like attaching a fish weight scale to a boot to see how many pounds it takes to move it, only this is much more scientific.
   The assumption is that the more pressure required to pull the weight, the more resistance exists on the floor, resulting in a more slip-resistant surface (and a higher value or reading). However, this can be misleading.
   For starters, a shoe that’s pulled across a textured surface – one that’s flamed, for example – won’t be 100 percent in contact with the sole of the tested material as it would in the real world. This could cause that tested flamed material to read a lower number than, say, a honed surface, when it’s just common sense that flamed material should have a greater slip resistance.
   Not possible, you say?   Let’s take a look at some SCOF values as published in a technical report from the Marble Institute of America on “Coefficient of Friction & Slip Resistance” and remember, the higher the number – the greater the slip resistance.

Belfast Black Granite    Flamed    0.83
                                            Honed        0.74
                  Polished    0.90

Let’s look at another to make sure this isn’t a one-time occurrence:

Dakota Mahogany        Flamed    0.78
                  Honed        0.75
                  Polished    0.94

   In fact, of the eight granites listed that had all three floor finishes, four of them had the polished surface as less slippery than the flamed. What does that tell us?
   For one thing, measuring machines can be flawed when it comes to textured surfaces, More importantly, many polished granites that may appear to be slippery, are anything but. That spells m-o-n-e-y … as in money saved in maintenance costs (because granite is the most-abrasive-resistant flooring available) and money made in sales and installation.
   Before you go out and purchase that Jaguar from all those increased sales in granite flooring, however, consider that there are a few more wrenches someone can toss into the works of our stone sales machine.
   These values are only good in the perfect-world environment of the laboratory, and we all know that stone can vary in mineral makeup from one slab to the next. It’s highly advisable to have the ratings for each and every sample that you sell for flooring. You probably don’t want to start hunting down the nearest test laboratory, so ask that quarries and wholesalers ensure proper readings on their products.
   Let us not forget also that it takes two to tango, as in cause-and-effect, for a slip to happen. What if you had the best slip-resistant surface going and it was covered in ball bearings and banana peels? And who would want to pay out on that claim?
   You think I’m being silly here? What about all of those tiny ball-bearing-like sand particles (which scratch the floors, I might add) that seem to collect in traffic areas, or that milkshake that went down in the south corridor that didn’t get a quick cleanup?
   It’s a fact of life in the real world: Slop Happens.
   This is where proper housekeeping comes into play, and it’s also where the baton is passed from the stone suppliers and installers to the maintenance staff. Everybody needs to be on the same team, so that a bad fall doesn’t become a big finger-pointing festival as three-day millionaires take advantage of our insurance policies.
   A housekeeping staff needs to have the proper entrance/walk-off matting in areas prone to sand, snow and other wetness and slip-enhancing elements. It’s a good idea to help these caretakers realize that once a mat is soaked or full of sand, it’s no longer working. (Some maintenance companies actually don’t realize this simple point). It is no longer protecting anybody and that will become their liability. Mats need to be cleaned and/or changed at regular intervals to ensure that they are doing their job.
   Also, wet areas are slippery, even on a textured surface. Hydroplaning isn’t just something that happens on a wet road as tires lose contact with the pavement; who hasn’t seen a young child slip and fall while running around a pool?
   Any liquid (especially oil) can make the most slip-resistant floor a skating rink. If the surface has been waxed (a no-no for stone), it becomes even more slippery. The housekeeping staff must extract all liquids as soon as humanly possible to avoid any lawsuits stemming from a slip.
   This is also a time to remind the need to damp mop, not slop mop. The whole point here is to reduce the amount of moisture, not add to it.
   Another thing to remember in this case is how much soap should be used. Many people think that more is better, but when it comes to soap (neutral cleaner for stone), less is better.
   Soap is designed to make water wetter (which is another story for another day), and wetter water is a slip hazard waiting to happen. I can hear the members of the FLLA (Frivolous Lawsuit Lawyers Association) drooling at the thought of wetter water.
   One thing that I have found to work to increase the SCOF is the application of an impregnating sealer. While this is something that can be debated among manufacturers and users of stone-maintenance products, I have to be honest: It works for me.
   In my company’s case, we found Miracle Sealants’ 511 Impregnator to add to the slip resistance of any surface we applied it to. Not all impregnators will do this, and water/stain protection is the first job of a sealer, but it’s worth trying a few to see the results on stopping slips.
   I first noticed this by – excuse the phrasing here – accident when we had applied the sealer to half of an installation, and we came back the next day to finish the job. While dust mopping, we couldn’t see where we’d started and finished the application until the dust mop hit the treated section – it was like the mop heads hit the airbrakes.
   Since there are a few people out there who’ll think we’re not applying it properly, I contacted Miracle about this. Apparently, a downtown Los Angeles building (built as First Interstate Tower, now the U.S. Bank Tower) went from nine slip/falls a year on their stone floors to one after the application of the product.
   In the Whole Truth Dept., Miracle noted that the slip resistance was an unintentional byproduct of their formula. And, as it turns out, my guys are applying it correctly.
   Stone flooring and slip-resistant finishes really are a matter of perception. No matter where you are in the process – materials distributor, installer, restorer or maintenance – you need to be fully aware of the physical properties of the flooring and how it can provide optimal slip-resistance through original finishes, daily upkeep, cleaning and treatment.
    Consider this advice to be your paper underwear. It is here to cover your heinie and the heinies of your friends (and customers) so you don’t slip and fall into a quicksand of legal actions.