Slips and falls are the second leading cause of accidental death around the world for people of all ages, especially for those who regularly walk, run, or work on slick surfaces. Non-slip shoes are one of the best ways to reduce your risk of a costly and potentially life-threatening accident. Here, we go over how non-slip shoes work, and how to find the right slip-resistant shoes for you.
What are Non-Slip Shoes?
While many shoes claim to be non-slip, there is no exact standard for what qualifies as slip-resistant footwear. The Occupational Safety and Health Administration, more commonly known as OSHA, currently has no specific definition of non-slip shoes.
When it comes to footwear, OSHA only requires the use of protective footwear for protection against objects that might crush or pierce the foot as well as electrical hazards. While the organization recommends non-slip footwear in specific environments, it doesn’t have any official safety standards that manufacturers must meet to label their shoes as “non-slip.”
Since OSHA offers no definitive standards, two pairs of shoes that claim to be “slip-resistant” may behave entirely differently on wet, oily, or otherwise slippery floors. Because of this, it’s important that you do your research before choosing the best shoe for you.
The best non-slip shoes often look and feel like just about any other shoe. However, they’ve been carefully engineered from the inside-out using unique materials and tread patterns. The design of non-slip footwear should offer the support and traction that you need to avoid slipping.
While a non-slip shoe can help to reduce your risk of falling, it’s not a guarantee of safety. You should still walk carefully and watch where you step, even in slip-resistant footwear.
What Makes a Shoe Non-Slip?
With no clear definition of what “non-slip” means, it can be a challenge to determine just how effective a shoe will be on slick surfaces. However, there are a couple of design features that help to increase traction while reducing slippage.
Typically, shoes are described as being composed of three parts. The insole runs along the bottom of the shoe, helping to support the bottom of the foot. The midsole is the material along the inner portion of the shoe to provide cushioning. Usually, it’s made of foam that’s soft enough for comfort while rigid enough to offer ankle support.
The outsole, however, is what’s most important when it comes to traction and stability. Often, this is the portion of your shoe that makes contact with the ground. Its overall design can have a significant impact on how well non-slip footwear can achieve grip.
Your outsole should offer maximum contact with the floor, especially in areas such as the heels and balls of your feet. The greater the surface area pushing against the ground, the more grip your footwear will give you. Shoes such as heels are often a poor choice for non-slip footwear, as they minimize contact with the floor.
That being said, it’s best to look for shoes with rounded edges on the soles. While this might reduce surface contact somewhat, the design also tends to allow water, oil, and other liquids to escape from under the shoe more easily than flat edges.
Grooves on the outsole can also enhance the flow of liquids. Many non-slip shoes have grooves cut along the sole that not only helps to increase flexibility but also promote the flow of water out from under the base of the shoe.
Many shoes that advertise themselves as “non-slip” have an intricate or irregular sole design. This itself offers no guarantee that the shoe will have better traction than one with a traditional sole. Instead, you should look for design features such as:
- Chevron (also known as Ultragrip) Sipe Soles: These soles work to clean themselves as they walk, allowing them to keep maximum tread grip.
- Safety-Loc Soles: These offer the best traction on smooth, wet surfaces.
- Cleated or Lug Soles: These multi-purpose soles are often used in heavy-duty industrial applications, offering maximum grip without sacrificing durability.
- Aluminum Oxide Grit: Soles treated with this material offer the maximum amount of grip. Aluminum oxide grit is abrasive, easy to apply, and artificially offers the traction you need on smooth surfaces.
Non-slip shoes can be made of a number of different materials. Slip-resistant footwear should be soft, pliable, and versatile. Shoes that are hard or stiff tend to have poor grip. As a rule of thumb, the softer the sole of a shoe, the better its non-slip capabilities.
When looking at non-slip shoe materials, you don’t have to worry too much about the insole or midsole. Instead, you should concentrate on the outsole construction. In addition to design, you should also pay close attention to construction.
Shoes are made of a variety of different materials that combine durability, stability, and grip. The latter two factors are the most important when considering non-slip shoe material. Footwear can be made of:
In general, a soft sole will give you a better grip than one that’s hard or stiff. One of the best materials for non-slip outsoles is rubber, as it’s pliable and offers reliable traction in both warm and cool weather conditions. High-quality rubber is able to provide grip even when exposed to oil and water.
The tread pattern is another important feature when it comes to slip resistance. Tread helps to increase the surface area of the sole and catch against uneven surfaces to prevent slipping. Many non-slip work and athletic shoes offer multi-patterned tread to give you traction from every angle. You can walk, run, and pivot without fear of falling.
Certain tread patterns can also help to disperse water when moving on wet floors. It’s best to look for an open tread pattern, as an enclosed one will trap water underneath your feet and cause hydroplaning. The same goes for shoes with flat or smooth soles, such as many sandals and heels.
The tread pattern of slip-resistant shoes should be interlocked, channeling water away from under the foot. It’s best to avoid patterns that feature shapes with flat edges such as triangles, squares, or hexagons. The edges can work to lock in water and prevent it from escaping the sole of the shoe.
Instead, look for tread patterns that feature circular shapes. Circles have no hard edges, allowing water, oil, and other liquids to flow more easily through gaps in the tread. Circles also increase the surface area of the sole, allowing for more contact with the ground. The more circles present in a pattern, the better the grip your shoe will have.
Regardless of the tread pattern, each individual shape should be spaced far enough apart to allow for the proper dispersion of liquids. If they are too close together, they’ll end up trapping water or oil and increase your risk of hydroplaning. There should be around at least two millimeters of space between tread shapes.
The depth of the tread is just as important as the spacing. If the pattern is too shallow, it won’t offer the grip that you need on slick surfaces. However, if the tread is too deep, it may get packed with dirt, rocks, and other debris. You should look for a depth of around three millimeters around tread shapes. This will allow liquids to disperse quickly without sacrificing traction.
You must monitor the tread on any pair of non-slip shoes as you use them. Over time the pattern will wear down, making it less effective at preventing falls. You should replace your shoes when you notice the grooves starting to wear down to less than two to three millimeters in depth.
If you want to make your own shoes non slip, check out this article: How to Make Shoes Non Slip.
When you’re out shoe shopping, you may notice that many brands label their footwear as “non-slip” or “slip-resistant” on the box. Don’t let those labels fool you, however. Since there’s no official standard set for slip-resistance, most of the labels you see on shoe boxes are completely arbitrary. A company can advertise a shoe as non-slip without having any actual evidence.
That being said, looking for non-slip labels is a good place to start. While it’s no guarantee that a shoe will offer superior traction on slick surfaces, you can always check the outsole design and tread pattern to see if the shoe will provide the grip that you need. You can look for labels that say either “non-slip” or “slip-resistant,” as these terms are used interchangeably.
If you see a shoe that’s advertised as “oil-resistant,” however, it doesn’t mean that the footwear is non-slip. Oil resistant generally refers to the top of the shoe and means that the material won’t suffer from grease or oil stains. It doesn’t tell you anything about the sole of the shoe.
You should also take claims such as “restaurant-tested” and “chef approved” with a grain of salt. These are often unbacked statements and used purely as a marketing ploy. Always be sure to thoroughly inspect a pair of slip-resistant shoes to see if it can hold up to the manufacturer’s claims.
When to Wear Non-Slip Shoes
Non-slip shoes can improve your stability and safety across a wide range of situations. Many hikers, joggers, and runners opt for non-slip athletic shoes when they step outdoors. Some people, especially those at a higher risk of slipping and falling, benefit from using non-slip shoes for daily activities such as walking around the house, going out to get the mail, grocery shopping, and more.
You can also find non-slip shoes in workplaces that often have wet or oily floors, such as restaurants, hotels, hospitals, and more. In fact, some workplaces require the use of non-slip shoes to reduce the risk of workplace accidents.
As a rule of thumb, if you’re going to be walking anywhere with a possibility of wet or oily floors, you should wear slip-resistant footwear. With the right shoes, you can help to prevent trips and falls when walking, running, and lifting heavy objects.
There are times, however, when non-slip shoes might be a poor choice of footwear. While slip-resistant shoes can help to prevent falling in normal or slick conditions, they do the opposite in snowy conditions. Snow easily packs into the grooves of the tread pattern, preventing your shoes from getting a good grip and increasing your risk of slipping. The same goes for mud.
If you do find yourself wearing non-slip shoes in these conditions, you should take regular breaks to clean the snow or mud from in between the tread of your footwear. Doing this will ensure that you don’t lose traction and help to keep you safe as you move.
Testing for Slip Resistance
While a non-slip label might not tell you much, some manufacturers put their shoes under rigorous testing before making such claims. Test results can give you a quantifiable indication of how well footwear will protect you from slipping. They prove that the outsole of a shoe is capable of performing on both dry and slick surfaces.
Different companies tend to have different standards when it comes to slip-resistance. However, there are only three main tests that almost all manufacturers use to test the friction of shoes against the floor.
The BOT-3000E digital tribometer is a machine that performs a test to measure non-slip capabilities on wet floors without human input. Results are measured in terms of the minimum dynamic coefficient of friction (DCOF). This value is a measurement of the force of friction between the sole of a shoe and the floor.
According to parameters set by the American National Standards Institute (ANSI), a pair of shoes offers “high slip resistance” if it tests for a minimum dynamic coefficient of friction (DCOF) of 0.43. On the other hand, if it has a minimum DCOF of 0.30, it’s considered to have “low slip resistance.”
The British Pendulum Tester
The British Pendulum Tester is the most widely used slip-resistance test in the world. Results are measured in terms of Pendulum Test Value, or PTV. In general, a PTV of 36 is considered the minimum safety standard for non-slip footwear.
However, there are separate standards specified for hard and soft rubbers when it comes to the pendulum test. Some countries have specific PTV values that manufacturers must meet for shoes expected to perform on ramps, crosswalks, pool decks, and more. Here’s a video on how the pendulum tester works:
SlipAlert is a type of tribometer that’s similar to the pendulum tester. Using a rollercoaster-like design, it allows for easy field testing of slip-resistance. However, it’s not often used in laboratories due to its size.
The Tortus digital tribometer test method does not meet ASTM International standards. However, it can be an incredibly useful test for shoe manufacturers. The machine can complete a record number of slip tests in a short timeframe. It can also test on both hard and soft rubbers, and in all weather conditions.
According to the Ceramic Tile Institute of America, the minimum DCOF for non-slip shoes that undergo the Tortus test is 0.5 for level floors. There are different DCOF values for inclines, ramps, and slippery floors. Here’s a quick video showing how the Tortus test works:
You can also test shoes out yourself in-store before purchasing them. Some shoe stores offer areas where you can try out shoes on smooth surfaces such as linoleum, tiling, and hardwood. If you can find such an area, try walking around in a given pair of shoes for a couple of minutes. You should also try sliding your foot to see how much resistance the sole provides.
Some stores don’t have a smooth floor for you to test out shoes. If this is the case, you can usually find another surface to try them on, such as a flat bench or shelving. While it’s not as good as walking, you can still slide the shoe along to get a feel for how much traction it offers on a dry surface.
If you feel the shoe slipping around when you test it out, that’s a good indication that it will perform poorly around water, oil, or other liquids. You should try out other pairs made of a different material or that offer a different tread pattern.
It’s also a good idea to test out a new pair of slip-resistant shoes on slick surfaces once you get home. Just because a pair of shoes offered superior traction on dry floors in-store doesn’t necessarily mean they can handle wet floors. Before wearing your shoes for the first time, carefully test them in water, oil, and soap to make sure that they offer the grip that you need.
The right pair of non-slip shoes can make a world of difference when it comes to personal safety. Whether you regularly jog in the rain, deal with slippery surfaces at work, or are simply concerned about your fall risk, swapping your shoes out for a non-slip pair can help to prevent dangerous accidents and injuries.