Artificial turf playing surfaces cause high surface temperatures when exposed to sunlight causing discomfort for players and coaches. According to Turfmagazine, the US has nearly 20,000 artificial turf fields and an estimated 1,500 new fields are built each year. Excessive field temperatures on artificial turf are common, causing heat-related illnesses and is a leading cause of sudden death among high school athletes. However, new infill technology can reduce surface temperatures in sports fields in arid parts of the country.
Since the seventies, coaches, players, parents and community members have worried about high temperatures on artificial turf fields. Since 1995, 64 football players have died from heat stroke, says the Centers for Disease Control. Of these, 47 were in high school, 13 in college, two professionals, and two in organized youth activities. In 90% of these cases, the fatal incidents occurred during practice.
Today, new artificial turf infill cooling technologies can reduce temperatures on artificial turf surfaces making the safety and well-being of players the number one priority. According to Fieldturf.com, infill is the cushioning layer of the turf system which absorbs impact on fall. More infill will lead to better shock absorption. Infills extend the life of the turf, keeps the artificial blades of grass standing upright, holds them down, adds weight and provides adequate pressure. On a national level, school administrators planning to add infills to their artificial turfs must ask the following questions:
- What are the different types of infill technology available now?
- How much will it cost to get the field cooler?
- H How does it perform? Does the ball get bounced and does it provide comfort to players?
- How much reduction in temperature will I get for my investment?
According to several studies, the surface temperatures of artificial turf playing surfaces are higher than natural grass surfaces when exposed to sunlight. Turf can become very hot when exposed to direct sunlight, especially during summer. Surface temperatures of traditional artificial turf can go anywhere between 95° F and 140° F higher than natural turfgrass surface temperatures. Surface temperatures of artificial turf systems can even go as high as 199.4° F on a day when air temperatures are 98.6° F. People who exercise in extreme heat are more likely to become dehydrated and get heat-related illness.
Data from Penn State’s Center for Sports Surface Research shows that the highest surface temperature recorded on an artificial turf surface was 200° F on a 98° F day in Provo, Utah (Williams and Pulley, 2002).
Heat gets transferred from the hot artificial turf surface to the sole of a player’s shoes, causing health issues for players. Researchers have found that heat transfer from the surface to the sole of an athlete’s foot creates physiological stress and serious heat-related health problems.
Different artificial turf infills help reduce surface temperatures in different degrees and but there is no magic pill that reduces temperatures considerably. and here are some common products:
BLACK CRUMP RUBBER
- Black crump rubber as an infill makes artificial turfs get very hot when exposed to direct sunlight. Rubber absorbs and radiates heat increasing the temperature above the field and making it hotter than the natural air temperature. In arid places like Las Vegas, an artificial turf using black crump rubber could emit over 150° F when the natural air temperature is 100° F. This product also emits bad odors., spreads dust and doesn’t kill any bacteria.
- According to Artificial Greens, silica sand is derived of quartz that has been eroded by wind and water. As the quartz erodes, it breaks into small granules and this material is used in artificial grass infill. Silica sand is the least expensive of infill material and does not hold the water down, causes breakdown of fibers, has antimicrobial properties and can absorb moisture causing bad odor.
- This artificial infill has been in use for over a decade and is an acrylic coated sand product with an anti-microbial coating and provides weight to the system, providing a softer landing. This considered to last longer than other traditional infill products and doesn’t absorb moisture.
- TCool is a patented technology, first introduced by Global Syn-Turf in 2018. This is specifically designed to prevent turf surfaces from overheating; it’s a pre-coat applied to artificial grass sand infill activated by adding moisture and does not use water. TCool has a special anti-microbial ingredient that eliminates pungent odors.
HEAT REDUCING INFILLS:
- Zeolite is a natural product from volcanic ash. This tan-colored product reflects heat and causes breakdown of fibers and needs to be filled in after a certain duration. This is a natural, anti-odor product and does not require water.
- Organic infills are pretty popular these days and are made from cork, coconut husk, walnut shells and wood. They are odorless and doesn’t retain heat, but instead retains moisture. According to Hellas, “the moisture is used to cool the surface temperature of the field, similar to how sweat cools the skin on a person’s body.”
HYBRID INFILL USING HEMP
- AstroTurf has a product called SuperNatural, a hybrid infill based on proven technology from German firm Melos and is combined with renewable raw materials.High quality organic hemp is woven inside EPDM (Ethylene Propylene Diene Monomer) and the hemp wicks water so SuperNatural absorbs water to lower temperatures. According to AstroTurf, the cooling effect is dictated by nature as moisture is absorbed. Water is absorbed and stored when it is damp only to be released again for cooling purposes when conditions are warm and dry.
An environment-friendly infill that can absorb water and provide a cooling effect on the field for an hour or two would be very beneficial to add to an artificial turf. Ideally, any product that makes the artificial field cooler by releasing more water to evaporate will be beneficial. New infill products made of quark, hemp and organics have arrived in the market offering advanced technology and better cooling features. Infills made of pinewood are popular. Organic products need additional water to make the field cooler. Innovative firms now use shock pads that have cups in them that can hold water and help.
CEI was recently awarded a design build contract to install a synthetic turf for a football and soccer field in a school district in Nevada. The project involved turf replacement, addition of an organic infill and an irrigation system. The school district was replacing ten-year-old synthetic turfs and adding new infill to bring down surface temperatures.
The cooling infill used was “Ecotherm with geo plus” and students now get additional hours to use the field as it helps to reduce the temperatures making it safe to play outside. Earlier, students had to come before 10 am or after 6 pm to use the fields causing disruptions to their normal schedules.
The costs of adding cooling infills vary depending on product choice. The range of the cost of adding an infill is typically between $20,000 and $70,000 depending on the product you choose, and average prices will hover around $50,000. To get the full cooling effect while using an infill, adding water would help. However, some school districts avoid using water because of the additional cost involved. A watering system could cost anywhere between $120,000 and $175,000 as it involves purchase of water cannons, a booster pump and obviously the cost for water. An additional cost is the use of shock pads that can range from $2 per square feet but some come along with this product.
In arid places like Las Vegas or Phoenix, school districts have to choose an irrigation system so that temperatures can be reduced substantially. Cooling infills do not need any extra maintenance costs except for utility costs for an irrigation system if that’s added.
Cities, counties and school districts in the Southwestern parts of the US are showing great interest in installing cooling infills using the latest technology. Newer cooling infills with irrigation systems are more environment friendly, reduce surface temperatures substantially reduce the odor produced by bacteria, less scheduled disruptions and provide multiple benefits to school districts.
Current demand from schools that require synthetic turf replacement and those deciding on installing new synthetic turf fields is at a 50:50 ratio and K-12 facilities managers know that it is a cost versus benefit question.