--- title: "Indoor Gym Turf: Fire Code and Air Quality | TIMELESS Grass & Greens" description: "Turf in a gym is a floor covering under the building code. Which fire tests apply near corridors and exits, and what federal research found in indoor field air." url: https://www.timelessgrass.com/blog/indoor-turf-for-a-gym/ updated: 2026-09-12 --- Commercial and sports # Indoor turf for a gym: fire rules and air quality * * * Updated 2026-09-12 The short answer ## What fire rules and air questions apply to turf in a gym? Under the 2021 International Building Code, a fibrous floor covering such as turf must pass the pill test in every occupancy. In corridors, exit passageways, stair enclosures and rooms open to a corridor, a gym classed as Group A or B also needs Class I or II material unless the building is sprinklered throughout. On air, federal researchers measured many chemicals at higher levels beside an indoor field with tire crumb infill than at outdoor fields. Planning a turf installation? Get a layout, turf options and a written quote for your space. [Request a free estimate](https://www.timelessgrass.com/estimate/) [Call 303-349-2368](tel:3033492368) We’ll call to arrange a free site visit. [Jump to the checklist](https://www.timelessgrass.com/blog/indoor-turf-for-a-gym/#checklist-before-you-order) On this page On this page 1. [Two questions to settle before you choose a product](https://www.timelessgrass.com/blog/indoor-turf-for-a-gym/#two-questions-to-settle-before-you-choose-a-product) 2. [Turf counts as a floor covering](https://www.timelessgrass.com/blog/indoor-turf-for-a-gym/#turf-counts-as-a-floor-covering) 3. [Test one: the pill test, everywhere](https://www.timelessgrass.com/blog/indoor-turf-for-a-gym/#test-one-the-pill-test-everywhere) 4. [Test two: a radiant panel class near corridors and exits](https://www.timelessgrass.com/blog/indoor-turf-for-a-gym/#test-two-a-radiant-panel-class-near-corridors-and-exits) 5. [Where a gym usually sits: Group A or Group B](https://www.timelessgrass.com/blog/indoor-turf-for-a-gym/#where-a-gym-usually-sits-group-a-or-group-b) 6. [What to ask the manufacturer for](https://www.timelessgrass.com/blog/indoor-turf-for-a-gym/#what-to-ask-the-manufacturer-for) 7. [What federal research found in the air at an indoor field](https://www.timelessgrass.com/blog/indoor-turf-for-a-gym/#what-federal-research-found-in-the-air-at-an-indoor-field) 8. [What that means for your infill choice](https://www.timelessgrass.com/blog/indoor-turf-for-a-gym/#what-that-means-for-your-infill-choice) 9. [Checklist before you order](https://www.timelessgrass.com/blog/indoor-turf-for-a-gym/#checklist-before-you-order) ## Two questions to settle before you choose a product Turf in a gym raises two questions an outdoor lawn doesn’t: - **Fire.** Indoors, turf is a floor covering, and the building code sets fire tests for floor coverings. Which tests apply depends on where the turf runs and how your building is classed. - **Air.** Federal researchers measured the air at a field with tire crumb rubber infill. Levels of many chemicals were higher at the indoor field than at the outdoor ones. Both decide what paperwork you ask for and which infill, if any, you use. The code sections below come from the [2021 International Building Code](https://up.codes/viewer/colorado/ibc-2021/chapter/8/interior-finishes) (IBC). Your city or county enforces the edition it adopted, with any local amendments. This is a summary, not legal advice, and your building department has the final word. ## Turf counts as a floor covering Section 804.1 of the IBC says interior floor finish and floor covering materials must meet the tests in Sections 804.2 through 804.4.2. The exception is narrow. It covers traditional floors such as wood, vinyl, linoleum or terrazzo, and resilient floor coverings “that are not composed of fibers.” Turf is made of fibers. So plan on the floor-covering rules applying, and ask your building official to confirm for your product. The federal carpet standard behind the first test is written broadly too. Under [16 CFR 1630.1](https://www.law.cornell.edu/cfr/text/16/1630.1), a carpet is any finished product made in whole or in part of fabric or related material, intended or reasonably expected to be used as a floor covering, above a minimum size. ## Test one: the pill test, everywhere Section 804.4.1 applies “in all occupancies.” Interior floor covering materials must pass the DOC FF-1 “pill test” under 16 CFR Part 1630, or ASTM D2859. The federal rule defines the ignition source as a flat methenamine tablet of about 150 mg and 6 mm across. We explain how the test runs, and what it can’t tell you, in [can artificial turf catch fire?](https://www.timelessgrass.com/blog/can-artificial-turf-catch-fire/) In short, it’s a small-flame lab test. It’s the minimum everywhere, and some parts of a gym need more. ## Test two: a radiant panel class near corridors and exits Section 804.4.2 adds a second test in certain places. It applies to floor coverings in: - enclosures for stairways and ramps - exit passageways - corridors - rooms or spaces not separated from corridors by partitions running from the floor to the underside of the ceiling In those places the material must reach a minimum critical radiant flux, tested under ASTM E648 or NFPA 253. Section 804.2 sets the classes: Class I is 0.45 watts/cm² or greater, and Class II is 0.22 watts/cm² or greater. Which class you need depends on the occupancy group. Class I is required in Groups I-1, I-2 and I-3. Class II is the minimum in Groups A, B, E, H, I-4, M, R-1, R-2 and S. Sprinklers change the answer. In a building sprinklered throughout under Section 903.3.1.1 or 903.3.1.2, Class II may be used where Class I is required. And a pill-test pass is enough where Class II is required. ## Where a gym usually sits: Group A or Group B Your building official assigns the occupancy group, but the [code’s own lists](https://up.codes/viewer/colorado/ibc-2021/chapter/3/occupancy-classification-and-use) show where gyms tend to land: - **Group A-3** names “Gymnasiums (without spectator seating).” - **Group A-4** covers indoor sporting events with spectator seating, such as arenas and tennis courts. - **Group B** includes “training and skill development not in a school or academic program,” naming martial arts studios and gymnastics “regardless of the ages served,” where the use isn’t classed as Group A. - **Small spaces.** Under Section 303.1.1, an assembly building or tenant space with an occupant load under 50 is classed as Group B. A and B appear in the same Class II list in Section 804.4.2. So for most gyms and training floors, the requirement reads like this: Where the turf goes Not sprinklered throughout Sprinklered throughout Corridors, exit passageways, stair or ramp enclosures, rooms open to a corridor Pill test, plus Class I or II Pill test A training room walled off from the corridor to the ceiling Pill test Pill test Confirm both columns with your building department before you order material. ## What to ask the manufacturer for Section 804.3 tells you what paperwork looks like. Floor coverings are tested by an agency under ASTM E648 or NFPA 253. They’re identified by a hang tag or similar, naming the manufacturer or supplier, the style and the classification. Test reports go to the building official on request. One line matters for turf with a pad: “Carpet-type floor coverings shall be tested as proposed for use, including underlayment.” If your building official treats turf as carpet-type, a result for the turf alone may not cover turf laid over a pad. Ask for results for the exact style and the pad you plan to use together. ## What federal research found in the air at an indoor field In February 2016, CDC/ATSDR and the EPA, with the Consumer Product Safety Commission, launched the [Federal Research Action Plan on tire crumb](https://www.epa.gov/chemical-research/federal-research-recycled-tire-crumb-used-playing-fields-and-playgrounds). Two reports cover playing fields. **Part 1 (July 2019)** sampled 40 fields with tire crumb rubber infill: 25 outdoor and 15 indoor. The [report](https://www.epa.gov/sites/default/files/2019-08/documents/synthetic_turf_field_recycled_tire_crumb_rubber_research_under_the_federal_research_action_plan_final_report_part_1_volume_1.pdf) found most organic chemicals at higher levels in the infill at indoor fields. With the lower ventilation rates indoors, it said exposures “may be higher for people using indoor fields.” It added that more research would be needed to confirm this. **Part 2 (April 2024)** measured exposure at two outdoor fields and one indoor field. The [report](https://www.epa.gov/system/files/documents/2024-04/tcrs-exposure-characterization-volume-1.pdf) found: - Many chemicals measured in the air next to the indoor field were at higher concentrations than at the two outdoor fields. - Methyl isobutyl ketone and benzothiazole were higher in the air at the indoor facility than at the outdoor field and in background samples. - Breathing appeared to be the main route for those two chemicals, with much higher estimated exposure indoors. The report adds that this rests on “a very small number of indoor field air measurements.” - There was no wind at the indoor field during sampling. It said indoor facilities may be the highest exposure setting, for two reasons. Indoor infill had higher levels of many organic chemicals, without the weathering thought to lower them over time outdoors. And indoors has “reduced ventilation rates, which can lead to higher air concentrations.” Keep the limits in view. EPA says the reports together “are not a risk assessment.” Across both parts, it says the findings support the conclusion that exposures can occur but are likely limited. ## What that means for your infill choice The research studied recycled tire crumb rubber. It doesn’t grade other infills or turf that uses no infill, good or bad. What it does give you is a clear reason to know what’s in your system: - **Ask what infill the system uses, if any,** and get the answer in writing. - **If you’d rather not have tire crumb indoors,** choose a system without it. That settles this particular question, and nothing more. - **Talk ventilation through** with whoever looks after your building’s mechanical systems, since reduced ventilation was one of the reasons the report gave. Our [indoor turf](https://www.timelessgrass.com/services/indoor-turf/) installations start with a free visit to measure the training space and check the existing floor. Your custom layout names the turf, any pad and any infill, and you approve it before work starts. ## Checklist before you order 1. **Ask your building department** which code edition applies and which occupancy group your space falls in. 2. **Mark where the turf runs:** corridors, exit passageways, stair or ramp enclosures, and rooms open to a corridor. 3. **Confirm whether the building is sprinklered throughout.** 4. **Get the pill-test result** (16 CFR 1630 or ASTM D2859) for the exact style. 5. **Where Class I or II applies,** get the ASTM E648 or NFPA 253 classification, tested with the pad you plan to use. 6. **Get the infill in writing,** including whether it’s tire crumb. 7. **Plan ventilation** before the floor goes in. ## Common questions ### Does the building code treat turf as a floor covering? Plan on it, and ask your building official to confirm. Section 804.1 of the [2021 International Building Code](https://up.codes/viewer/colorado/ibc-2021/chapter/8/interior-finishes) exempts traditional floors such as wood, vinyl, linoleum and terrazzo, and resilient floor coverings "that are not composed of fibers." Turf is made of fibers, so it doesn't fit that exception. ### What's the difference between Class I and Class II? Both come from a radiant panel test, ASTM E648 or NFPA 253. Class I is 0.45 watts/cm² or greater, and Class II is 0.22 watts/cm² or greater. Class I is the stricter of the two. The [code](https://up.codes/viewer/colorado/ibc-2021/chapter/8/interior-finishes) lets Class II stand in for it only in a building sprinklered throughout. ### Does a sprinkler system change what the turf needs? Yes. Where a building is sprinklered throughout under Section 903.3.1.1 or 903.3.1.2, the [2021 IBC](https://up.codes/viewer/colorado/ibc-2021/chapter/8/interior-finishes) permits Class II material where Class I would be required, and a pill-test pass where Class II would be required. The pill test itself still applies everywhere. ### Did the federal research find indoor turf unsafe? It didn't set out to answer that. [EPA](https://www.epa.gov/chemical-research/federal-research-recycled-tire-crumb-used-playing-fields-and-playgrounds) says the reports together are not a risk assessment. They found exposures may be higher at indoor fields, from a very small number of indoor air measurements, and supported the conclusion that exposures overall are likely limited. ### Do the findings apply to other infills? No. The fields in the study used recycled tire crumb rubber infill ([EPA Part 1 report](https://www.epa.gov/sites/default/files/2019-08/documents/synthetic_turf_field_recycled_tire_crumb_rubber_research_under_the_federal_research_action_plan_final_report_part_1_volume_1.pdf)). The research tells you nothing about other infills, or turf with no infill, in either direction. ## Related turf questions - [Is artificial turf wheelchair accessible?](https://www.timelessgrass.com/blog/is-artificial-turf-wheelchair-accessible/) - [Painted, tufted or inlaid lines on a synthetic field?](https://www.timelessgrass.com/blog/painted-or-inlaid-lines-on-a-turf-field/) - [Artificial turf on a dog-friendly restaurant patio in Florida](https://www.timelessgrass.com/blog/turf-for-a-dog-friendly-restaurant-patio-florida/) ## Where to go next - [Indoor facility turf](https://www.timelessgrass.com/services/indoor-turf/) - [Commercial turf](https://www.timelessgrass.com/services/commercial-turf/) Useful links - [2021 International Building Code, Chapter 8, Section 804 (interior floor finish), as published on UpCodes for Colorado](https://up.codes/viewer/colorado/ibc-2021/chapter/8/interior-finishes) - [U.S. EPA: Federal Research on Recycled Tire Crumb Used on Playing Fields and Playgrounds](https://www.epa.gov/chemical-research/federal-research-recycled-tire-crumb-used-playing-fields-and-playgrounds) - [EPA and CDC/ATSDR (April 2024): Tire Crumb Rubber Exposure Characterization, Final Report Part 2, Volume 1 (EPA/600/R-24/020.1)](https://www.epa.gov/system/files/documents/2024-04/tcrs-exposure-characterization-volume-1.pdf) Free estimate ## Planning a turf installation? Tell us about the area you want to install or replace. We’ll call to arrange a free site visit. [Or call 303-349-2368](tel:3033492368) Your free estimate includes - A visit to measure your space - A custom layout, drawn for your space - Turf options, side by side - A written price, with no pressure to sign [Request a free estimate](https://www.timelessgrass.com/estimate/) Five short steps. We’ll call to arrange your visit.