Worship Space Acoustic Requirements Under ISO 3382
Churches, mosques, synagogues, temples. Typical volume: 500-20,000 m³.
What ISO 3382 Requires for a Worship Space
Clause reference: ISO 3382-1:2009 Annex B
RT60 target: Speech: 1.0-1.5s | Music-led: 2.0-3.0s | Mixed: 1.5-2.0s
STI target: ≥ 0.45 (speech intelligibility) | STI ≥ 0.60 for PA systems
Background noise limit: NR-25
Measurement condition: Unoccupied
Note: Highest design complexity — conflicting requirements for speech and music
How to Calculate ISO 3382 Compliance for a Worship Space
- 1
Identify the applicable standard and target
Look up ISO 3382 (ISO 3382-1:2009 Annex B). For a worship space, the RT60 target is Speech: 1.0-1.5s | Music-led: 2.0-3.0s | Mixed: 1.5-2.0s. Measurement condition: unoccupied.
- 2
Measure or model the room geometry
Record the length, width, and height of the room to calculate the volume. A typical worship space has a volume of 500-20,000 m³.
- 3
List all surfaces and their absorption coefficients
For each surface (floor, ceiling, walls, windows, doors), find the absorption coefficient at each octave band frequency (125Hz to 4kHz) from ISO 354 test data or a materials database.
- 4
Calculate total absorption and apply the Sabine or Eyring equation
Sum all surface absorption values: A = sum of (alpha x area). Then apply T60 = 0.161 x V / A (Sabine) or T60 = -0.161 x V / (S x ln(1 - alpha_avg)) (Eyring). Use Eyring when average alpha exceeds 0.20.
- 5
Compare result against the standard and specify treatment if needed
If the calculated RT60 exceeds the target of Speech: 1.0-1.5s | Music-led: 2.0-3.0s | Mixed: 1.5-2.0s, specify additional absorption. Variable — adjustable absorption systems common is typical for a worship space to achieve compliance.
Typical Acoustic Treatment for a Worship Space
Treatment Area
Variable — adjustable absorption systems common
Estimated Cost
£120-£280/m² of floor area
Frequently Asked Questions
What RT60 does ISO 3382 require for a worship space?
ISO 3382 (ISO 3382-1:2009 Annex B) requires a reverberation time of Speech: 1.0-1.5s | Music-led: 2.0-3.0s | Mixed: 1.5-2.0s for worship space spaces, measured in the unoccupied condition per ISO 3382-2.
What background noise level is acceptable in a worship space under ISO 3382?
ISO 3382 sets a background noise limit of NR-25 for worship space spaces. This typically refers to HVAC and building services noise measured with the room unoccupied.
How much acoustic treatment does a worship space need to comply with ISO 3382?
A typical worship space requires Variable — adjustable absorption systems common of acoustic treatment to meet ISO 3382 compliance. Estimated installed cost is £120-£280/m² of floor area.
Calculate ISO 3382 Compliance for Your Worship Space
Enter your room dimensions, select materials, and instantly verify compliance against ISO 3382. Free, no signup required.
Open Free RT60 Calculator