Safety at our Core.

The AIRCAP 1™ by thrml.™ ASTM F1346-23 Certification

 

The AIRCAP 1™ by thrml.™ hot tub cover was intentionally engineered as a manual safety cover to fully comply with ASTM F1346-23 — the current (as of 2023) Standard Performance Specification for Safety Covers and Labeling Requirements for All Covers for Swimming Pools, Spas and Hot Tubs published by ASTM International. This standard sets rigorous performance, testing, and labeling criteria to reduce drowning risk by inhibiting access to the water for children under five years old when the cover is properly installed and used according to manufacturer instructions.

 

Our Design Principles for ASTM F1346-23 Compliance thrml.'s™ development team prioritized safety as a foundational requirement alongside thermal performance and sustainability. The AIRCAP 1™ achieves compliance through these key design elements:

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1. High Load-Bearing Capacity (Static Load/Weight Support)
   The standard requires a safety cover to support a minimum distributed load equivalent to approximately 485 lbs (roughly the combined weight of two adults and one child) over a specified area (often tested in a 3-foot radius or similar) without collapsing, tearing, or allowing breakthrough that could permit access to the water.

   • AIRCAP 1™ incorporates a reinforced, high-density structural core (with air-capturing insulation layers) bonded to durable outer fabrics and perimeter reinforcements.

   • This creates a rigid system that distributes weight evenly and prevents dangerous sagging or failure under load, passing the required static load tests.

2. Perimeter Integrity and Deflection Resistance
   The cover must resist perimeter deflection and gaps that could allow a child (or test probe simulating one) to slip through between the cover edge and the hot tub/spa wall.

   • Custom-fit contours and precise edge profiling ensure a tight, secure seal around the hot tub's coping or shell.

   • Our integrated heavy-duty heat welded straps with keyed locks maintain constant downward pressure and eliminate hazardous openings, even under stress or attempted probing.

3. Child-Resistant Fastening and Securing Mechanisms
   Fasteners must be designed to prevent easy removal by young children while allowing adult access.

   • AIRCAP 1™ uses lockable or tamper-resistant straps with buckles, the same locks that have been used by the hot tub and spa industry for decades.

   • These mechanisms require deliberate adult action to release, meeting the standard's child-inhibition goals.

4. Surface and Drainage Performance
   The cover must not accumulate dangerous water volumes (e.g., from rain) that could create additional hazards or reduce effectiveness.

   • The outer material and slight contouring promote proper drainage away from the center, preventing pooling while maintaining insulation integrity.

5. Labeling and Marking Requirements
   ASTM F1346-23 mandates specific permanent markings on the cover, including:

   • Identification as a "safety cover" (when qualified).

   • Manufacturer name, model, and compliance statement.

   • Installation/use instructions and child safety warnings.

   • AIRCAP 1™ includes clearly visible heat-sealed labels with all required information, plus icons for quick recognition.

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Why This Matters for thrml.™

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By designing The AIRCAP 1™ to exceed the strictest of safety requirements, thrml.™ not only provides the best, high-performance thermal cover ever built but also delivers genuine family protection—often satisfying or contributing to local building codes (e.g., in states like California) that accept compliant safety covers in lieu of or alongside fencing for hot tubs/spas. This dual focus on safety and planetary health (energy efficiency, durable materials, zero-plastic packaging) makes AIRCAP 1™ a standout in the replacement and OEM markets.