Safety Standards & Certifications for Underwater Windows
An underwater window is not just a transparent surface but a load-bearing structural element that has to withstand considerable hydrostatic pressure and an aggressive chemical environment. Below you will find the materials, calculations, approvals and tests behind every Hydrosight window.
Material Quality & Standards
We exclusively use monolithic cast acrylic (PMMA) for our underwater windows. Unlike laminated safety glass, our cast acrylic blocks offer superior optical clarity and structural integrity without the risk of delamination.
- Manufacturing Standard: Our raw blocks are manufactured in strict accordance with EN ISO 7823-1 ("Plastics – Poly(methyl methacrylate) sheets – Types, dimensions and characteristics – Part 1: Cast sheets").
- Certified Supply Chain: We partner exclusively with leading global manufacturers whose production facilities are certified to ISO 9001 (quality management) and ISO 14001 (environmental management).
- Verified Properties: We guarantee the characteristic values required for structural design, ensuring high tensile strength and an elastic modulus consistent with long-term structural safety.
- Chemical Resistance: Our systems are verified for resistance to standard pool chemicals (chlorine, ozone) and can be adapted for saltwater and marine applications.
Structural Verification & Engineering
Every pool project is unique. Hydrosight provides full engineering support to ensure your installation meets local building codes and safety requirements.
- Structural Calculations: We provide detailed structural calculations for the acrylic glazing and the stainless steel frame (V4A / AISI 316Ti / 1.4571), taking into account water pressure, thermal expansion and impact loads.
- Finite Element Analysis (FEA): For complex geometries or high-load scenarios, we use advanced calculation methods to verify stress distribution and deflection limits.
- Construction Tolerances: The stainless steel frame and the mortar joint compensate for deviations in the concrete shell of up to ±30 mm.
Read more about installation tolerances
Regulatory Approval (Germany: ZiE)
In Germany, underwater windows made of acrylic are classified as "non-regulated construction products" (nicht geregelte Bauprodukte). For public pools, this typically requires a Zustimmung im Einzelfall (ZiE) (case-by-case approval) from the state building authority.
Hydrosight is your expert partner for the ZiE process:
- Experience: We have successfully managed numerous ZiE procedures with state authorities.
- Documentation: We provide all necessary compliance documents, including Factory Production Control (FPC) records, manufacturer declarations in accordance with the respective state building code (Landesbauordnung) and inspection reports.
- Expert Network: We collaborate with accredited testing institutes for structural plastics to obtain the necessary expert opinions (Gutachten) on structural safety and serviceability.
International Compliance
Outside Germany, there are typically no special regulatory requirements (such as the ZiE) for underwater windows. In most international markets, project approval is straightforward and based on standard structural verification.
- Eurocode: Design and calculation based on EN 1990 (basis of structural design) and EN 1991 (actions on structures). Structural verification of the stainless steel frame according to EN 1993 (design of steel structures).
- ASME PVHO: Upon request, we can manufacture according to ASME PVHO-1 (Safety Standard for Pressure Vessels for Human Occupancy).
Quality Assurance & Testing
- 100 % Leak Testing: Every Hydrosight window undergoes a documented pressure and leak test at our factory before shipment.
- Traceability: Full batch tracking of raw materials ensures that every window can be traced back to its specific production block.
Learn more about our factory sealing process and warranty
Contact
Contact our engineering team to discuss your project requirements and to get support with structural calculations and local approvals.