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ISO 25649-6:2024 — Floating Leisure Articles — Safety Requirements and Test Methods for Class D Devices
Comprehensive guide to safety requirements, performance testing, and engineering design for water trampolines, climbing structures, and floating action modules.
Introduction to ISO 25649-6 and Class D Devices
ISO 25649-6:2024 is the sixth part of the ISO 25649 series, specifying additional safety requirements and test methods for Class D floating leisure articles. Class D devices encompass large inflatable structures designed for active recreational use on water surfaces, including water trampolines, climbing structures, bouncing platforms, and modular action courses. These products are characterized by their substantial size, collective use patterns, and the inherent risks associated with jumping, climbing, and falling into water.
Class D devices are intended for persons older than 36 months who are able to swim. These products are designed for active use including jumping, playing, climbing, and related activities on the inflatable surface.
The standard addresses critical safety aspects including floating stability under full and single-sided load, collision risks between users, entrapment and entanglement hazards, safety distances, and sufficient water depth relative to jumping and potential falling heights. This second edition (2024) supersedes the 2017 version with significant technical revisions including updated scope, enhanced residual buoyancy requirements for structures exceeding 1.5 m height, new climbing function provisions, and comprehensive water depth calculation methodologies.
| Parameter | Requirement | Test Method Reference |
|---|---|---|
| Minimum user age | > 36 months, must be able to swim | Clause 1 |
| Max user height on device | Determined by structural design | 4.3 |
| Residual buoyancy (>1.5 m height) | Enhanced requirements apply | 4.5.3.1 |
| Safety pad thickness | Minimum specified for trampoline areas | 4.5.13 |
| Horizontal safety distance | Calculated from device height | 4.5.9 |
| Water depth minimum | Proportional to jump/fall height | 4.5.8 |
For Class D devices exceeding 5 m in height, Annex B provides specific additional information that designers must incorporate into their risk assessment and safety documentation.
Key Safety Requirements and Engineering Considerations
The standard organizes safety requirements into several critical categories. Design of buckles and fixings (Clause 4.2) specifies force requirements for all fastening mechanisms to prevent accidental opening during use. Sizing and admissible number of users (Clause 4.3) establishes per-person space requirements for trampoline surfaces and other activity areas. The in-water performance requirements (Clause 4.5) form the core of the standard, covering floating stability, buoyancy, re-embarkation facilities, anchorage, and water depth calculations.
One of the most technically demanding aspects is the residual buoyancy calculation for partially deflated scenarios. Unlike conventional buoyancy devices, Class D structures must maintain sufficient flotation even when some compartments are compromised. The 2024 revision added specific language for structures exceeding 1.5 m height, recognizing that taller structures present greater risks in the event of partial deflation.
Key engineering improvement in the 2024 edition: new requirements for climbing functions (4.5.5.6) address the growing popularity of inflatable climbing walls on water, specifying minimum handhold depth, maximum spacing, and load testing procedures.
The standard also introduces comprehensive water depth calculation methodologies (4.5.8.1 and 4.5.8.2) that consider the specific product type, maximum user height, and intended activities. This represents a significant advancement over generic depth recommendations, enabling designers to optimize for safety while accommodating diverse product configurations.
Testing Protocols and Compliance Verification
ISO 25649-6 establishes rigorous test methods for verifying compliance. The floating stability test simulates worst-case loading scenarios including all users positioned on one side, evaluating the device’s resistance to capsizing. The buoyancy test measures total and residual buoyancy under both fully inflated and partially deflated conditions.
For trampoline-specific components, the safety pad test (4.5.13) evaluates impact attenuation properties using standardized drop tests. Padding must demonstrate sufficient energy absorption to prevent injury during normal use and foreseeable misuse scenarios.
The valve and stopper test (4.4.2) is particularly important for Class D devices, as these large structures rely on maintaining inflation pressure across multiple compartments. Valves must withstand specified torque and pull forces without leaking, and stoppers must remain securely in place under dynamic loading.
Product certification to ISO 25649-6:2024 requires documented evidence that the manufacturer has conducted a comprehensive risk assessment covering all foreseeable use scenarios, including overcrowding, use by non-swimmers, and collision with surrounding objects.
Anchorage and Safety Distance Design
Class D devices may be either anchored in position or free-floating, each configuration presenting distinct safety considerations. The anchorage requirements (4.5.7 and Annex D) specify minimum anchor point strength, number of attachment points relative to device size, and inspection intervals for mooring components.
Horizontal safety distances (4.5.9) establish minimum clearance from surrounding objects based on device dimensions and activities. For jumping devices, the safety zone extends laterally beyond the device footprint to accommodate user trajectories during falls or dismounts.
| Device Type | Min. Horizontal Clearance | Water Depth Requirement | Anchorage Points |
|---|---|---|---|
| Trampolines (D1, D2) | 1.5× device width | Proportional to fall height | Min. 4 points |
| Climbing structures | 2.0× max structure height | Based on climbing height | Min. 6 points |
| Bouncing platforms | 1.5× platform width | Min. 1.2 m for low platforms | Min. 4 points |
| Modular action courses | Site-specific assessment | Varies by module | Per module design |
Engineering Design Insights
For engineers designing Class D floating leisure articles, several practical insights emerge from the standard. First, compartmentalization is critical — dividing the inflatable structure into multiple independent air chambers ensures that a single puncture does not lead to catastrophic loss of buoyancy. The standard’s residual buoyancy requirements effectively mandate minimum compartment counts for larger structures.
Second, interface design between modular components requires careful attention to prevent entrapment points. The 2024 revision specifically addresses this through new requirements for modular arrangements (Annex C), which is increasingly relevant as water parks deploy configurable activity courses.
When designing modular Class D systems, consider that Annex C now requires specific assessments of pool use configurations, including interface gaps, step transitions between modules, and cumulative loading effects.
Third, material selection directly impacts both safety and durability. The standard references material requirements from ISO 25649-1, but designers should note that UV resistance, seam strength, and abrasion resistance are particularly important for products exposed to sun, saltwater, and continuous use. PVC-coated polyester fabrics with minimum 900 denier and welded (rather than glued) seams represent the current industry best practice for Class D devices.
Frequently Asked Questions
Q: What is the difference between Class D and Class E devices under ISO 25649?
A: Class D devices are large inflatable structures for active use including jumping, climbing, and bouncing on water surfaces. Class E devices are inflatable boats designed for rowing and paddling. Class D focuses on impact protection and anchorage; Class E focuses on hull integrity and stability.
A: Class D devices are large inflatable structures for active use including jumping, climbing, and bouncing on water surfaces. Class E devices are inflatable boats designed for rowing and paddling. Class D focuses on impact protection and anchorage; Class E focuses on hull integrity and stability.
Q: Does ISO 25649-6:2024 apply to floating platforms used in pools?
A: Yes, Annex C provides specific requirements for pool use of water park modules or modular arrangements, addressing the unique considerations of confined pool environments versus open water installations.
A: Yes, Annex C provides specific requirements for pool use of water park modules or modular arrangements, addressing the unique considerations of confined pool environments versus open water installations.
Q: What are the key changes from the 2017 edition to the 2024 edition?
A: Major changes include updated scope, enhanced residual buoyancy requirements for structures >1.5 m, new climbing function regulations, detailed water depth calculations, expanded repair kit requirements, and a new annex for devices exceeding 5 m height.
A: Major changes include updated scope, enhanced residual buoyancy requirements for structures >1.5 m, new climbing function regulations, detailed water depth calculations, expanded repair kit requirements, and a new annex for devices exceeding 5 m height.
Q: How is the maximum number of users determined for a Class D device?
A: The standard specifies minimum space per person for trampoline surfaces and other activity areas. The maximum user count is calculated by dividing the usable surface area by the per-person allocation, considering the specific activity type and device configuration.
A: The standard specifies minimum space per person for trampoline surfaces and other activity areas. The maximum user count is calculated by dividing the usable surface area by the per-person allocation, considering the specific activity type and device configuration.
