Synthetic Running Track Material Testing: Standards, Testing Items, and Laboratory Methods

Synthetic running track material testing verifies that polyurethane and rubber-based athletic surfaces comply with strict requirements for mechanical performance, sports function, durability, and chemical safety. This technical guide explains the scope of running track material testing, the applicable standards such as GB 36246-2018, GB/T 22517.6, EN 14877, and IAAF/World Athletics specifications, typical sample types, key testing items, and the laboratory methods used by accredited third-party laboratories.

Technical Overview

Synthetic running tracks (also called plastic or all-weather tracks) are polymer-based sports surfaces constructed from polyurethane (PU) binders combined with EPDM rubber granules, recycled SBR crumb rubber, and mineral fillers. Common system types include prefabricated factory-made sheets bonded to an asphalt or concrete base, cast-in-situ (poured-in-place) solid systems, breathable spray-coated systems, and sandwich/composite constructions.

Material testing serves three core objectives. First, it verifies sports functional performance, including shock absorption, vertical deformation, and slip resistance, which directly affect athlete comfort, energy return, and injury risk. Second, it confirms mechanical durability under climatic and mechanical loading over the design life of the surface. Third, it controls chemical safety: excessive solvents, free isocyanates, heavy metals, and plasticizers in low-quality track materials have caused well-documented health concerns, prompting mandatory limits on harmful substances in school sports surfaces.

• GB 36246-2018 – Chinese mandatory national standard limiting harmful substances in synthetic surface layers for primary and middle school sports areas
• GB/T 22517.6 – Chinese standard for sports functional performance and mechanical requirements of synthetic track surfaces
• EN 14877 – European specification for surfaces for outdoor sports areas
• IAAF / World Athletics Track Certification System – performance requirements for competition tracks
• ISO and ASTM rubber test methods – supporting methods for tensile, hardness, and aging properties

Testing Samples

Prefabricated Track Sheets

Factory-manufactured rolls or cut sheets are sampled directly from production batches. Test specimens are die-cut from the finished product and conditioned in the laboratory before physical, functional, and chemical testing. This sample type allows full verification of both surface and base layer properties as delivered.

Liquid Raw Materials

Two-component polyurethane binders, single-component sealants, primers, and spray topcoats are sampled from sealed containers. The liquids are cast into plaques under controlled temperature and humidity, fully cured, and then tested for mechanical properties and harmful substance content.

Rubber Granules

EPDM granules and recycled SBR crumb rubber are sampled in bulk. Granules are tested as-received for chemical limits and, where required, mixed at the site ratio with binder to prepare composite specimens reflecting the actual field formulation.

Field-Cut Specimens

Core samples and cut blocks are removed from an installed track at agreed locations, typically after construction and before acceptance. These specimens confirm that the as-built surface, including binder, granules, and installation workmanship, meets the specified requirements.

Testing Items

Physical and Mechanical Properties

• Total thickness of the surface layer
• Tensile strength and elongation at break
• Shore A hardness
• Compression recovery and rebound resilience
• Flame retardancy (self-extinguishing behavior)
• Adhesion/bond strength to the base, where applicable

Sports Functional Properties

• Force reduction (shock absorption), typically required between 35% and 50%
• Vertical deformation, typically between 0.6 mm and 2.5 mm
• Friction and slip resistance (wet and dry)
• Resistance to running spikes and stud loading
• Ball rebound, for combined-use multisport surfaces

Durability and Aging Properties

• Artificial weathering (xenon-arc UV exposure) with color change and mechanical retention
• Heat aging and thermal cycling
• Hydrolysis and water immersion resistance
• Acid and alkali resistance
• Abrasion and wear resistance

Chemical Safety (Harmful Substances)

Under GB 36246-2018, finished track products must comply with limits covering eighteen categories of harmful substances. Key items include, but are not limited to:

• Formaldehyde
• Benzene; toluene plus xylene (sum)
• Free toluene diisocyanate (TDI)
• Soluble heavy metals: lead, cadmium, chromium, and mercury
• Volatile organic compounds (VOC)
• Short-chain chlorinated paraffins (SCCPs)
• MOCA (3,3′-dichloro-4,4′-diaminodiphenylmethane) and related aromatic amines such as 4,4′-diaminodiphenylmethane
• Phthalate plasticizers (DEHP, BBP, DBP sum; DINP, DIDP, DNOP sum)
• Polycyclic aromatic hydrocarbons (PAHs), including benzo[a]pyrene
• Odor intensity rating

For non-product materials such as bulk adhesives, sealants, and rubber granules, additional limits apply for total lead, cadmium, chromium, hexavalent chromium, mercury, arsenic, selenium, nickel, zinc, and copper, together with the relevant organic parameters listed above.

Testing Methods

Mechanical Testing

Tensile strength and elongation at break are measured on standard dumbbell specimens using universal testing machines in accordance with ISO 37 / GB/T 528. Hardness is determined with a Shore A durometer per ISO 48 / GB/T 531, and thickness is measured by calibrated gauge or optical methods at defined locations across the specimen.

Sports Function Testing

Force reduction is measured with a Berlin Artificial Athlete drop assembly that impacts the surface and compares the absorbed force to a rigid reference, following EN 14808 and the corresponding GB/T 22517.6 method. Vertical deformation is determined with the same apparatus operated in deformation mode per EN 14809. Slip resistance is evaluated with a pendulum friction tester per EN 13036-4. For certified competition venues, in-situ testing is performed at defined grid points across all lanes.

Chemical Analysis

Volatile substances, benzene series, and free TDI are quantified by headspace gas chromatography–mass spectrometry (GC-MS). Formaldehyde is determined by spectrophotometric methods after controlled extraction. Soluble heavy metals are extracted under simulated gastric acid conditions and quantified by inductively coupled plasma optical emission spectrometry (ICP-OES), ICP-MS, or atomic absorption spectroscopy (AAS). Phthalates, PAHs, and short-chain chlorinated paraffins are analyzed by GC-MS and GC-MS/MS techniques, while aromatic amines are determined by liquid or gas chromatographic methods.

Durability Testing

Accelerated weathering is performed in xenon-arc chambers per ISO 4892 / GB/T 16422, followed by assessment of color difference and retention of tensile properties. Heat aging is conducted in air-circulating ovens per GB/T 3512, and chemical resistance is evaluated by immersion in standard reagents followed by visual and mechanical inspection.

Odor Evaluation

Odor intensity is assessed by a trained sensory panel under controlled conditions and graded on the scale defined in the annex of GB 36246-2018, with higher grades triggering corrective investigation even when chemical limits are individually met.

Applications

Synthetic running track material testing is applied across the full project lifecycle, from raw material qualification to in-service condition assessment:

• Mandatory acceptance inspection of tracks at primary and middle schools under GB 36246-2018
• Performance verification and certification of competition tracks for stadiums seeking IAAF / World Athletics class certification
• University stadiums, professional training bases, and municipal sports centers
• Factory quality control and type approval of prefabricated track products
• Incoming material inspection of binders, granules, and additives before construction
• Bid qualification, contractual compliance, and third-party arbitration in construction disputes
• Condition assessment of aged tracks prior to renovation or resurfacing
• Export compliance testing against EN 14877 and other regional specifications

FAQ

Which standards govern synthetic track testing in China?

GB 36246-2018 is the mandatory national standard for harmful substances in synthetic surfaces used in primary and middle school sports areas, while GB/T 22517.6 specifies the sports functional and mechanical requirements of track surfaces. Competition venues are additionally tested against the IAAF / World Athletics track certification requirements.

What is the difference between product and non-product samples?

Product samples are the finished surface materials, either prefabricated sheets or cured cast-in-situ mixtures, and are tested against the finished-product limits. Non-product samples are the constituent raw materials, such as liquid binders, sealants, and rubber granules, which must meet separate limits including a wider list of total heavy metals.

Can testing be performed on site?

Yes. Sports functional properties such as force reduction, vertical deformation, and slip resistance are commonly verified in situ on the completed track. Chemical safety testing, however, requires laboratory analysis of specimens cut from the field or prepared from sampled raw materials.

What is force reduction and why is it important?

Force reduction measures the percentage of impact force absorbed by the surface compared with concrete. A value that is too low transmits excessive shock to athletes, while a value that is too high wastes energy and slows performance, so tracks are required to fall within a defined window, typically 35% to 50%.

How long does testing take?

Standard physical and chemical testing of a complete sample set is typically completed within seven to fifteen working days after sample receipt and conditioning. Aging and weathering programs, which require extended exposure periods, may extend the schedule by several weeks.