The E of CHIMES stand for environment. Now it’s very easy to understand the environment from the perspective of where our building is positioned. If we have an external walkway in Manchester vs one in Mauritius, then, other than in the monsoon season, you’ll probably find that there’s more rain in Manchester and therefore, from an environmental perspective, the seasons are perhaps against us a bit more.
The weather is only one aspect of this. When it comes to the weather though. It’s not just rain we need to think about there’s also clearly winter weather in terms of snow and ice, also but something that is often not thought about or not understood well as condensation. I did some work once for a shopping centre which had a link bridge between two sides of the site which travelled over a road but had no operable windows. Therefore, you would not expect the floor to become wet. However, for some reason, it would “sweat”, and therefore you’d have water contamination building up on the floor, which would cause people to slip. I’ve seen a similar phenomenon at Victoria station in London on some of its terrazzo flooring.
Over-and-above the weather, what do we mean when it comes to the environment, more holistically? The general built environment and how that affects people’s susceptibility to slip. So, we’re thinking about steps and stairs, we’re thinking about slopes, we’re thinking about things like, grab rails, we’re thinking about lighting, we’re thinking about noise, we’re thinking about humidity. All of these things can play a role in terms of whether somebody may slip or not.
Let’s start with surfaces that we might be stepping on. If we have a gradient on the floor, this increases our requirement for friction. In simple terms, if we’ve got a surface in the high to moderate slip resistance categories when wet, for every degree of slope, we increase our requirement for friction by about 5000x. In terms of the pendulum, for every degree of slope, you need to add on PTV 1.75 to achieve the benchmark so on a flat surface.
Where we have slopes where the floor is likely to get contaminated, we need to think of these as a higher risk environments. This will include areas like poolsides and changing rooms where you have falls in the floor of, typically 1-1.5 degrees so the water will go down into drains. You find the same in kitchens.
Steps and stairs, is another big factor and we’ll deal with that in a separate area.
The consistency… Another example we see often is in commercial kitchens where you have resin floors installed. One of the challenges with this particular type of floor is that the aggregates, which is required to give the floor a texture, is cast into the floor surface manually. So, what you can find are areas where you can go from one foot to the next having the difference between a one in a million slip resistance and one in two!
Building entrances are a huge topic which we’ve covered separately: what makes a building entrance safe?