How many turnstiles do I need? Calculating lanes from your peak flow
Quick answer
Divide the number of people arriving in your busiest minute by the number one turnstile lets through per minute in real use, round up, and add a spare lane if a breakdown must not stop entry. The figure that matters is the peak, not the daily total.
Why the daily total is no use
A centre with 1,000 entries a day spread over twelve hours is comfortable with one turnstile. A factory with 300 people arriving in ten minutes is not. Queues are caused by how many people arrive at once.
The method, step by step
- Measure the peak. Count how many people arrive in the busiest 5 or 10 minutes (shift change, start of classes, opening). With no data, estimate what share of staff arrives together.
- Convert to people per minute. For example, 240 people in 10 minutes is 24 per minute.
- Find the equipment's real capacity. The manufacturer's data sheet gives passages per minute in ideal conditions. As a guide, figures of around 15 to 20 for a tripod and 30 to 40 for a speed gate are common; a full-height turnstile is slower. Always use the figure for the specific model.
- Apply a real-use factor. People hunt for their card, hesitate or misread the first time. Cutting the catalogue figure to a half or two thirds is a prudent assumption.
- Divide and round up.
- Add a spare if a faulty turnstile must not stop entry.
Example (assumed figures)
- Peak: 24 people per minute.
- Tripod rated at 18 per minute; estimated real use, 10.
- 24 ÷ 10 = 2.4 → 3 turnstiles, plus the accessible gate.
With speed gates rated at 35 per minute and 20 in real use: 24 ÷ 20 = 1.2 → 2 lanes.
The example figures are illustrative. Your calculation must use the data sheet of the equipment chosen and your real peak.
What else matters
- Direction. Bidirectional turnstiles can be set to entry in the morning and exit in the afternoon.
- The credential. A proximity card reads faster than a QR code on a phone screen.
- Queueing space. If the queue spills onto the street or a staircase, you need more lanes even if the sum is tight.
- Exit. If exit is also controlled, calculate its peak separately.
What this calculation does not cover
The width needed to evacuate the building is calculated under different rules — those of the Spanish Building Code — and is separate from entry comfort. Turnstiles must never be counted to reduce it: see access control and evacuation.
Before you buy
Check on plan that the calculated turnstiles, the pass gate and manoeuvring space actually fit (installation requirements). If they do not, another type of turnstile may suit better.
We can run this calculation with you as part of our turnstile installation service.
Frequently asked questions
Is it better to under- or over-provide?
Under-providing shows every day as queues and side doors propped open "to be quicker", which defeats the control. If you are between two figures, at least pre-install the cabling for the extra unit.
Does a bidirectional turnstile count as two?
Not at the same time: only one person passes at any moment. It does let you split lanes between entry and exit by time of day.
This guide is for information only and is not a substitute for legal advice or for the technical design of each installation. Regulations change: always check the current text at the official source.