Anechoic Chamber
Polyurethane (PU) foam plays a critical role in the design of anechoic chambers, where it is used as a sound-absorbing material. These chambers are designed to eliminate sound reflections and external noise, creating an acoustically “dead” environment—ideal for testing microphones, speakers, sonar devices, or conducting psychoacoustic experiments.
Description
Note: For low-frequency absorption, PU foam is often used alongside bass traps or hybrid materials like mineral wool or fiberglass.
Why Polyurethane Foam Is Used in Anechoic Chambers
PU foam is engineered into pyramid, wedge, or convoluted (egg crate) shapes to:
Absorb sound energy across a wide frequency range (especially mid to high frequencies)
Prevent sound reflections by diffusing and dissipating acoustic waves
Control reverberation time, ensuring a reflection-free environment
Improve sound isolation from external noise sources
Key Features of PU Foam for Acoustic Use
| Feature | Benefit |
| Open-cell structure | Traps and converts sound energy into heat, enhancing absorption |
| Lightweight & flexible | Easy to install, shape, and mount on walls, ceilings, and floors |
| Custom shapes (wedge/pyramid) | Enhances surface area for greater sound absorption |
| Frequency tuning | Foam thickness and shape can target specific frequency ranges |
| Fire-retardant grades available | Meets safety standards for industrial and commercial test environments |
Common Applications in Anechoic Environments
- Electroacoustic Testing (speakers, microphones, smartphones)
- Radar & RF Anechoic Chambers (with foam treated for electromagnetic absorption)
- Noise Measurement Chambers (automotive, appliance industries)
- Audio Product Development (headphones, studio monitors, hearing aids)
Specifications for PU Acoustic Foam in Anechoic Chambers
| Parameter | Typical Value |
| Density | 25–40 kg/m³ (1.5–2.5 lb/ft³) |
| Thickness | 2–12 inches depending on frequency coverage |
| NRC (Noise Reduction Coefficient) | 0.75–1.00 (varies by design) |
| Shape | Wedge, pyramid, egg-crate, or custom-molded |
| Fire Rating | UL 94 HF-1, FMVSS 302, or BS 476 Class 1 |
Advantages of PU Foam in Anechoic Chambers
- High acoustic absorption with minimal space requirement
- Customizable in shape, density, and thickness
- Cost-effective compared to alternative materials
- Non-dusting & safe for indoor use (when certified)
- Lightweight — ideal for suspended or mobile chambers
Related Products and Applications
Office Chairs
Office ChairsPolyurethane (PU) foam is a core material in ergonomic office chairs, providing the necessary cushioning, support, and durability for extended sitting periods. Its versatility allows manufacturers to design seats and backrests that balance comfort with posture support.
NVH Solutions, Gaskets & Seals
NVH Solutions, Gaskets & Seals
NVH Solutions, Gaskets & Seals
NVH Solutions, Gaskets & SealsPolyurethane (PU) foam plays a vital role in Noise, Vibration, and Harshness (NVH) control in vehicles, as well as in the production of gaskets and seals. Its unique combination of flexibility, durability, and sealing properties helps manufacturers enhance cabin comfort, reduce noise levels, and ensure tight seals in various automotive systems.
Outdoor Furniture
Outdoor Furniture
Outdoor Furniture
Outdoor FurniturePolyurethane (PU) foam is commonly used in outdoor furniture cushions and padding for its comfort, flexibility, and ability to be engineered for outdoor durability. However, not all PU foam types are suitable for outdoor use—special formulations like reticulated (open-cell) or quick-dry foam are preferred for weather resistance.
Baby Products
Baby ProductsPolyurethane (PU) foam is used in many baby care products for its softness, flexibility, cushioning, and lightweight properties. However, due to the sensitive nature of infant products, strict safety standards and certifications are crucial.
