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Material Durability Testing

Silicone membrane performance proven under extreme conditions.

CRT Laboratories tested the Green Drain silicone membrane to ASSE 1072 Section 3.9 requirements for tear strength, chemical resistance, UV stability, ozone exposure, and temperature extremes. The results exceeded every minimum threshold by wide margins.

What this test covers.

The silicone membrane is the critical functional component of the Green Drain. It is the flexible seal that opens under water flow and closes to block sewer gases, odors, and pests. ASSE 1072, Section 3.9 (Table 3), requires the barrier membrane material to pass a series of physical and chemical durability tests before the product can be certified.

CRT Laboratories, Inc. (1680 North Main Street, Orange, CA 92867) performed this testing as an ISO 9001:2008 certified and ISO/IEC 17025:2005 accredited laboratory. The work was subcontracted by IAPMO R&T Lab (Ontario, CA) under IAPMO Project #24772, Work Order 19741-S1. The report was issued on June 22, 2015.

The test evaluated six distinct material properties: split tear strength, ozone resistance, chemical resistance (acid and alkali), UV stability (tensile and elongation retention after exposure), water absorption, and low-temperature brittleness. Each property was tested using the corresponding ASTM standard method specified in ASSE 1072.

These results remain valid today. The 2025 IAPMO recertification test report (1554-25004) references this CRT report for Section 3.9 compliance rather than retesting the material, confirming that the silicone formulation and its documented properties have not changed.

Detailed test procedures and results.

Each test followed a specific ASTM method referenced in ASSE 1072-07(2013), Section 3.9, Table 3. Below is the methodology and outcome for every property tested.

Split Tear Strength

Method: ASTM D 624-00, Type C die at 23C. Measures the force required to propagate a tear through the membrane material.

Result: 23.38 kN/m. The minimum requirement is 0.25 kN/m, making the measured value 93 times higher than the threshold. The membrane is extremely difficult to tear during installation or normal use.

Ozone Resistance

Method: ASTM D 1149-07, Method B. Specimens exposed to 150 parts per hundred million (pphm) ozone concentration at 40C for 100 continuous hours.

Result: No cracking or crazing observed. This is critical for sewer gas environments where ozone and other reactive gases are present in drain lines.

Chemical Resistance

Method: ASTM D 543-06. Specimens immersed for 72 hours at 74F (23C) in two solutions: 1% sulfuric acid and 1% sodium hydroxide. Weight change measured against a 10% maximum allowance.

Result: Sulfuric acid: +0.17% weight change. Sodium hydroxide: +0.21% weight change. Both results are negligible and far below the 10% maximum, confirming the membrane withstands both acidic and alkaline chemical exposure.

UV Resistance

Method: ASTM G 154-12a. Specimens exposed to 500 hours of UVB 313 lamp radiation, then tested for changes in tensile strength and elongation per ASTM D 412-06a. Maximum allowable change: -50%.

Result: Tensile strength changed -17.49% (from 853 PSI to 726 PSI). Elongation changed -15.85% (from 656% to 552%). Both values are well within the -50% maximum, confirming UV stability for outdoor and rooftop drain installations.

Water Absorption

Method: ASTM D 471-06. Specimens immersed in water for 48 hours at 158F (70C). Weight change measured against a 20% maximum allowance.

Result: +0.36% weight change, versus the 20% maximum allowed. The membrane absorbs virtually no water and will not swell or degrade from constant water contact.

Low-Temperature Brittleness

Method: ASTM D 2137-11. Specimens tested at -40F (-40C) for brittleness. The material must show no cracking, breaking, or loss of flexibility at this temperature.

Result: No brittleness observed. The membrane maintains full flexibility at -40F, supporting installation in freezing climates, cold storage facilities, and outdoor drains in winter conditions.

Industries where membrane durability is critical.

Material performance data matters most in environments where drains face chemical exposure, temperature extremes, strict hygiene requirements, or all three. This testing is relevant to healthcare facilities, food service and food processing, industrial and manufacturing, and data centers and cold storage environments where the membrane must withstand demanding conditions. Hospitals and clinics use aggressive disinfectants daily, and the membrane's chemical resistance to both acids and bases means it withstands bleach, hydrogen peroxide, peracetic acid, and quaternary ammonium compounds without degradation. Commercial kitchens discharge hot water, grease, and cleaning chemicals through floor drains continuously, and the membrane handles temperatures up to 212F while resisting alkaline degreasers and acid sanitizers. Manufacturing floors expose drains to solvents, acids, and caustic wash-down chemicals, giving engineers the confidence to specify Green Drain in pharmaceutical production, chemical plants, and heavy manufacturing environments. Data center sub-floor drains and cold storage freezer drains operate at temperature extremes, and the membrane's proven performance from -40F to 212F means it maintains a reliable seal across all of these conditions.

Test results at a glance.

Four headline numbers from the CRT Laboratories material test. Every measured property exceeded the ASSE 1072 minimum requirement.

93x Tear Strength Over Minimum 23.38 kN/m measured vs. 0.25 kN/m required (ASTM D 624)
-40F to 212F Operating Temperature Range No brittleness at -40F, rated to 212F continuous
656% Initial Elongation Stretches to 6x its length before failure (ASTM D 412)
500h UV Exposure Passed Only 17.5% tensile loss vs. 50% maximum allowed

Why membrane material matters.

The membrane is the only moving part in a Green Drain waterless trap seal. Its material properties directly determine how long the product lasts, what environments it can be installed in, and how reliably it performs over time.

A tear strength 93 times the minimum requirement and 656% elongation mean the membrane resists damage from debris, installation handling, and repeated flexing cycles. These numbers explain why Green Drain membranes last years in the field without cracking, tearing, or losing their seal. The membrane operates from -40F to 212F, resists ozone degradation in sewer gas environments, and retains over 80% of its tensile properties after 500 hours of UV exposure, allowing installation in rooftop drains, freezer rooms, boiler areas, and outdoor applications where rubber or plastic alternatives would fail.

Silicone maintains flexibility across a wider temperature range than natural rubber, EPDM, or thermoplastic elastomers. It does not off-gas, does not absorb water, and resists both acid and alkali chemistry. These properties are why medical devices, food processing equipment, and aerospace components use silicone where reliability is non-negotiable. With less than 0.25% weight change after 72 hours in both sulfuric acid and sodium hydroxide solutions, the membrane withstands daily cleaning with quaternary ammonium compounds, bleach solutions, enzymatic drain cleaners, and alkaline degreasers. Facilities do not need to modify their cleaning protocols to accommodate the product.

Documentation

Green Drain Spec Pack (2025)

The CRT membrane material test data is included in the Green Drain Spec Pack (pages 25-26). This 46-page document also contains all certifications, test reports, product dimensions, and installation instructions.

  • CRT Laboratories Report 19741-S1 (full test data)
  • IAPMO ASSE 1072-2020 test results
  • All certification certificates
  • Product specifications for all 8 models

Frequently asked questions.

How durable is the Green Drain silicone membrane?

CRT Laboratories tested the membrane to ASSE 1072 Section 3.9 requirements and found a split tear strength of 23.38 kN/m, which is 93 times the 0.25 kN/m minimum. The membrane also demonstrated 656% initial elongation, meaning it can stretch to over 6 times its original length before failure. These properties, combined with ozone resistance, chemical resistance, and UV stability, make the silicone membrane exceptionally durable for long-term drain installations.

How often does the membrane need to be replaced?

Green Drain membranes are designed to last years under normal use. The CRT material testing confirmed exceptional resistance to ozone, UV, chemicals, and temperature extremes. The 2025 IAPMO recertification (Report 1554-25004) referenced the original 2015 CRT material data without requiring retesting, confirming that the material properties remain valid over a decade later. Actual replacement intervals depend on drain traffic, chemical exposure, and water temperature in the specific installation.

What chemicals can the membrane withstand?

The silicone membrane was tested per ASTM D 543-06 in both sulfuric acid (1%) and sodium hydroxide (1%) for 72 hours. Weight change was negligible: +0.17% in acid and +0.21% in alkali, both well under the 10% maximum allowed. The membrane also showed near-zero water absorption (+0.36% after 48 hours at 158F vs. the 20% maximum). This means the membrane withstands acidic drain cleaners, alkaline sanitizers, and prolonged water contact without degradation.

What temperature range can the membrane handle?

The CRT test confirmed the membrane shows no brittleness at -40F (-40C) per ASTM D 2137-11, and the material is rated for continuous use up to 212F (100C). This covers freezing outdoor installations, boiling water discharge from commercial kitchens, and everything in between. Separate DTI testing confirmed the membrane maintains performance after 1,500 thermal cycles between 93C and 15C.

Is the silicone membrane safe for food service environments?

Yes. The silicone material has been independently verified for safety through multiple certifications. Green Drain holds NSF/ANSI 2 certification for food equipment, HACCP International endorsement for food safety environments, and California Proposition 65 compliance (no detectable lead or phthalates). The CRT chemical resistance data further supports use in food service, where the membrane regularly contacts sanitizers and cleaning agents.

Need material test data for your project specification?

Download the full Spec Pack for CRT test data, or contact our engineering team for material compatibility questions and project-specific technical support.