The first question when choosing acoustic panels is always "which thickness should I pick?" Thickness is not just a spec — it determines which frequencies get absorbed and how quiet your space can become. Based on the international acoustic standard DIN 18041, we break down exactly what each thickness does.
"NRC 0.84 means the material absorbs 84% of sound energy. That is enough to make a noticeable difference in a typical office environment."
NRC Performance by Thickness
Tornex PET acoustic panels are available in three KCL-certified thicknesses. NRC 0.75 or higher is classified as "excellent absorption." But the real story is in the frequency-specific data — here is where thickness truly makes a difference.
0.79
NRC
9T (9mm)
Lightweight · Partitions · Corridors
0.84
NRC
12T (12mm)
Standard · Offices · Schools
0.90
NRC
24T (24mm)
High-performance · Studios · Auditoriums · Ceiling (louver/cloud type recommended)
PET 패널 외 목모보드, 멜라민폼 등 다른 흡음재와의 비교가 필요하다면? 2026 흡음재 완전 가이드 — PET·목모보드·멜라민폼 비교 분석도 함께 확인하세요.
Where Thickness Really Matters: Low & Mid Frequencies
At high frequencies (1,000 Hz and above), all three thicknesses perform similarly — absorption coefficients exceed 1.0 (saturation). The real difference emerges in the 250–500 Hz range, where thicker panels pull ahead significantly.
"Korean is a vowel-centric language — mid-frequency absorption (250–1,000 Hz) is the key to speech clarity in Korean-speaking offices."
Detailed Thickness Comparison
| Specification | 9T (9 mm) | 12T (12 mm) | 24T (24 mm) |
|---|---|---|---|
| NRC | 0.79 | 0.84 | 0.90 |
| 250 Hz (α) | 0.34 | 0.62 | 0.85 |
| 500 Hz (α) | 0.72 | 0.82 | 0.92 |
| 1,000 Hz+ (α) | ≥ 1.0 | ≥ 1.0 | ≥ 1.0 |
| Fire Rating | Fire Retardant Certified (shipped with certification label) | Fire Retardant Certified (shipped with certification label) | Fire Retardant Certified (shipped with certification label) |
| Weight (per m²) | 2.0 kg | 2.4 kg | 4.0 kg |
| DIN 18041 Match | Group B (corridors) | Group B4 (offices) | Group A3–A4 (meeting rooms) |
| Best For | Under 30 m² | 30–100 m² | 100 m²+, Ceiling |
토넥스 PET 흡음재 제품이 궁금하신가요?
토넥스 PET 흡음재 제품 보기 →Frequently Asked Questions
Q Which thickness is best for a standard open-plan office?
12T (12 mm) is the most popular choice for open-plan offices. With NRC 0.84, it absorbs everyday work noise effectively while keeping weight and installation manageable. Per DIN 18041 Group B4 (A/V ≥ 0.25), covering about 40% of the wall area in a typical office meets the standard for workplace comfort.
Q Is fire-retardant certification mandatory?
Yes — multi-use facilities, educational buildings, and public spaces require fire-retardant materials by Korean fire safety law. All Tornex PET panels carry Fire Retardant Certified status and are shipped with the certification label attached.
Q Can I feel the difference between NRC 0.79 and 0.84?
The 0.05 NRC difference seems small, but it becomes noticeable as room area increases. In spaces over 30 m², the cumulative absorption difference with 12T vs 9T adds up meaningfully. More importantly, 12T absorbs significantly more at 250 Hz (α 0.62 vs 0.34) — that is where Korean speech clarity improves most.
Q Why does thickness matter more for Korean speech?
Korean is a vowel-centric language with most speech energy in the 250–1,000 Hz range. Unlike languages with heavy consonant emphasis, Korean clarity depends heavily on mid-frequency absorption. This is precisely where thicker PET panels (12T, 24T) outperform thinner ones.
Q What is DIN 18041 Group B4?
DIN 18041 is the international standard for room acoustics. Group B4 covers spaces where noise reduction and comfort are essential — open-plan offices, reception counters, government offices. The guideline requires A/V ≥ 0.25 (absorption area / room volume ratio), meaning a certain minimum amount of acoustic treatment per cubic meter of space.
Need PET Acoustic Panels?
Tornex offers 107 colors and 3 thicknesses — the optimal acoustic solution tailored to your space.
Request a Consultation →