Entry Sensor Accuracy: Why It Really Matters
The Difference Between Okay Data and Decision-Grade Insights
The Bottom Line
Many entry sensor systems claim 95–98% accuracy — sounds good, right? But in practice, that small difference from 99.7%+ accuracy can mean dozens of people miscounted every day. This is compounded if entry events are missed in a particular direction.
If you’re using these numbers to make decisions about space, safety, or resourcing — accuracy matters.
What Does “1,000 Events” Actually Mean?
Think about a regular day at the office: A person enters, goes to the bathroom, grabs lunch, then leaves — that’s at least 4 events per person. For simplicity, let’s say 6 events per person per day.
So: 1,000 events ≈ ~167 people.
Accuracy Comparison (Real-World Impact)
Accuracy | Sensor Errors | Actual Floor Count | People Drift | What That Means |
95% | 50 errors | 167 ppl | ~25 people off | 15–30% of people miscounted — not reliable |
98% | 20 errors | 167 ppl | ~10 people off | Better, but still not ideal for planning |
99.7% | 3 errors | 167 ppl | ~1–2 people off | Trustworthy for real decisions |
Why Small Errors Become Big Problems
You’re not just counting people once — you’re tracking every movement. A few missed or extra events quickly stack up if you’re making decisions such as:
- “Do we need another floor?”
- “Can we reduce cleaning zones?”
- “Is this team really using their space?”
Coverage Range and Accurate Entry Sensor Positioning is Critical
Often people’s exit path is slightly different to their entry. Perhaps to hit a button to unlock a door, or because a double door opens more easily on entry. This can lead to drift in a certain direction. This drift compounds throughout the day and quickly reduces trust in the system.
Where High Accuracy Makes a Difference
Use Case | Without High Accuracy | With 99.7% Accuracy |
Space Planning | Misjudged headcounts | Confident consolidation decisions |
Live Dashboards | False alerts or missed activity | Accurate real-time info |
Compliance & Safety | Inaccurate occupancy logs | Reliable historical data |
Resource Allocation | Over/under-servicing | Efficient spend & logistics |
