🏢ISO 3382-1:2009 · International

Open Plan Office Acoustic Design to ISO 3382-1:2009

Open plan offices present a unique acoustic paradox: speech must be intelligible within conversation groups but unintelligible beyond the distraction distance to preserve privacy and concentration. ISO 3382-3:2012 defines the key metrics — spatial decay rate D2,S, distraction distance rD, and A-weighted SPL of speech at 4 m (Lp,A,S,4m).

TL;DR

Under ISO 3382-1:2009, a open plan office of 400-600 m³ (typical dimensions 20m × 10m × 2.8m) requires an RT60 of ≤ 0.8s at 500-2000 Hz. ISO 3382-3:2012 is the definitive standard for open-plan office acoustics.

RT60 Target

≤ 0.8s

Noise Limit

N/A

STI Minimum

N/A

Frequency Range

500-2000 Hz

Specific Requirements

Parameter	Target	Clause Reference	Notes
Frequency Range	500-2000 Hz	—	Octave bands for compliance assessment

Step-by-Step Compliance Calculation

1
Define ISO 3382-3 parameters
Set targets for D2,S (>= 7 dB), Lp,A,S,4m (<= 48 dB), and rD (<= 5m) based on office activity type.
2
Design ABC strategy
Absorb (ceiling/walls), Block (screens/partitions), Cover (sound masking) — all three elements are needed.
3
Model spatial decay
Use acoustic modelling software to predict D2,S and rD for the proposed design and furniture layout.
4
Measure per ISO 3382-3
Conduct measurements along representative paths using an omnidirectional source and measure SPL decay with distance.

Recommended Materials

Surface	Material Category	Min NRC	Coverage %
Ceiling	High-performance ceiling tile	0.90	90%
Desk screens	Absorptive screen panel	0.85	100%
Masking	Sound masking system	0.00	100%

Browse the full acoustic materials database for absorption coefficients and product specifications.

Common Failure Modes

⚠️Distraction distance exceeds 5m

Without combined absorption, screening, and masking (ABC principle), rD typically exceeds 8-10m in open offices.

⚠️Low spatial decay rate

D2,S below 5 dB indicates insufficient spatial attenuation. Target is D2,S >= 7 dB for good acoustic comfort.

Frequently Asked Questions

What RT60 does ISO 3382-1:2009 require for a open plan office?

ISO 3382-1:2009 requires a reverberation time of ≤0.8s at 500-2000 Hz for open plan office spaces. ISO 3382-3:2012 is the definitive standard for open-plan office acoustics. It defines spatial decay rate D2,S, A-weighted SPL of speech at 4m (Lp,A,S,4m), and distraction distance rD. These metrics replace simple RT60 as the primary performance indicators for speech privacy and comfort in open offices.

Does ISO 3382-1:2009 set a background noise limit for a open plan office?

ISO 3382-1:2009 does not specify a background noise limit specifically for open plan office spaces. For noise criteria, refer to complementary standards such as BS 8233 or ASHRAE Handbook Chapter 49, which provide recommended background noise levels for this room type.

How much acoustic treatment does a open plan office need to comply with ISO 3382-1:2009?

A typical open plan office (400-600 m³) requires High-performance ceiling tile (NRC ≥0.9) covering 90% of the ceiling as the primary treatment. Additional wall absorption on 2 surface(s) is typically needed. Use the AcousPlan calculator with the pre-loaded dimensions (20m × 15m × 2.8m) to calculate the exact absorption deficit for your room.

Calculate ISO 3382-1:2009 Compliance for Your Open Plan Office

Pre-loaded with typical open plan office dimensions (20m × 15m × 2.8m) and an RT60 target of 0.8s per ISO 3382-1:2009. Enter your actual dimensions, select materials, and verify compliance instantly.

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