Key Takeaways

• Office phone booths should be evaluated using verified acoustic performance data rather than vague claims that they are soundproof.
• ISO 23351-1 measures speech level reduction and classifies office booths according to how effectively they reduce sound transmission.
• Class A and A+ booths may be preferable in quiet workplaces where speech privacy and minimizing distractions are especially important.
• Wall construction, acoustic glass, door seals, ventilation design, and interior sound absorption all influence a booth’s acoustic performance.
• Comparing laboratory reports, inspecting construction details, and testing booths in person can help businesses make more informed purchasing decisions.

Ask ten suppliers whether their phone booth is soundproof and you will get ten confident yeses. Ask them how many decibels of speech it stops, under which test, and the room usually goes a little quieter.

That gap matters, because acoustics are the main reason anyone buys a booth in the first place. Leesman’s 2026 research on workplace noise, drawn from more than 600,000 employee responses, describes people coming in early just to get some quiet, a coping habit rather than a culture. Its advice is that offices need a mix of spaces, including small rooms set aside for calls.

A booth that only takes the edge off conversations will not fix that. Here is how to tell real acoustic performance from good copywriting.

Sound travels in two directions

A phone booth has two acoustic jobs. The first is keeping speech in, so the person on a call is not broadcasting to the desks around them and confidential conversations stay confidential. The second is keeping office noise out, so the person inside can hear and think.

Most buyers focus on the first, and that is sensible: speech escaping into an open-plan office is one of the most distracting sounds there is. But if your booths will also be used for focused work, the second job deserves equal weight.

The number that matters: speech level reduction

Since 2020, there has been a common yardstick. ISO 23351-1 measures how much a booth reduces the level of speech passing through it, expressed in decibels as a speech level reduction (written DS,A). Products are then grouped into classes:

The class is not just a label. Researchers presenting at Forum Acusticum / Euronoise 2025 ran laboratory experiments comparing how speech from booths of different classes affects people working nearby. Their results favored Class A booths for both cognitive performance and how disturbing people found the sound, and they recommend Class A where the aim is to minimize the effects of irrelevant speech.

So the first question to any supplier is simple: what class is this booth, and can I see the lab report?

Why your office changes the answer

The same booth can feel very different in two offices. Background noise acts as a natural mask. In a lively sales floor with a steady hum, a Class B booth may be more than enough. In a quiet law firm or a library-style focus zone, the same leakage becomes easy to hear, and a Class A or A+ product earns its premium.

It is worth measuring your office’s background level, even roughly with a phone app, before deciding which class you need.

What actually makes a booth quiet

Once you know the number, it helps to understand what drives it, so you can judge whether a booth will keep performing over time.

Mass and layers. Walls built from several layers of different materials stop more sound than a single thick panel. Ask what is inside the walls, not just what covers them.

Glass. The glass door and any glazed panels are usually the weakest link. Laminated safety glass with an acoustic interlayer performs far better than standard toughened glass of the same thickness.

Seals. A booth is only as quiet as its gaps. Look at the door seals, the joints between panels and how the booth meets the floor. Seals that compress and wear should be easy to replace.

Ventilation openings. Every booth needs airflow, and every air path is also a sound path. Well-designed booths route air through lined channels or silencers so that fresh air gets in while speech does not get out. That is why makers such as MEAVO design airflow and acoustics together rather than bolting a fan onto a quiet box.

Interior absorption. Soft felt or acoustic foam inside the booth does not stop sound escaping, but it does reduce echo. That makes the booth feel calmer and improves call quality, because microphones pick up less reverberation.

Test it with your own ears

Specs get you to a shortlist; your ears should make the final call. Step inside, close the door and have a colleague speak at normal volume outside, then swap. Listen for the door seal, the ventilation, and any rattle when someone walks past.

If you can, compare two or three brands in the same week. Whether you are looking at a Scandinavian name or a European maker such as MEAVO, the test is the same, and the differences become obvious very quickly.

Comparing booths before you buy

Once you have a shortlist, it helps to see the numbers in one place rather than across a stack of brochures. Independent sites such as Office Pod Guru, which compare the best office phone booths by acoustic class, ventilation and pricing, make it far easier to separate tested performance from marketing claims.

Questions to ask every supplier

1. What is the ISO 23351-1 speech level reduction, and which lab tested it?
2. What glass is used in the door and panels?
3. How is ventilation routed, and does it reduce acoustic performance?
4. Which seals wear over time, and can they be replaced on site?
5. Can I test the booth in a showroom or on a trial basis?

The takeaway

Soundproofing is the reason a phone booth exists, so it deserves more scrutiny than any other feature. Ignore vague claims, ask for the ISO class, match that class to your office’s background noise and then trust your ears. A booth that genuinely keeps speech in is one people will actually use, and that is the whole point.

FAQs

What does soundproofing mean when choosing an office phone booth?

In practice, soundproofing refers to how effectively a booth reduces sound transmission between its interior and the surrounding workplace. Buyers should look for measured acoustic performance rather than assuming that a product advertised as soundproof will prevent all speech from being heard.

What is ISO 23351-1, and why does it matter?

ISO 23351-1 is a standard used to measure speech level reduction in furniture units and enclosures, including office phone booths. Its results help buyers compare products using a consistent testing method instead of relying solely on manufacturers’ marketing claims.

Which acoustic class is best for an office phone booth?

Class A or A+ may be suitable for workplaces where speech privacy and minimizing distractions are priorities, particularly in quieter offices. Class B may provide adequate performance in noisier environments, but the appropriate choice depends on the office’s background noise, intended use, and privacy requirements.

What features affect an office booth’s acoustic performance?

Important features include layered wall construction, acoustic glazing, well-fitted door seals, carefully designed ventilation channels, and secure panel joints. Interior acoustic absorption also helps reduce echoes and improve call quality, although it does not by itself prevent sound from escaping.

How can businesses test an office phone booth before buying?

Businesses should review the ISO 23351-1 laboratory report, inspect construction details, and ask whether the supplier offers a showroom demonstration or trial. Testing the booth with normal speech and checking ventilation noise, door seals, and rattling can reveal practical differences that product specifications alone may not show.