How to implement biometric attendance

Choose the device type for your workforce

Fingerprint readers cost the least and are widely used, but they struggle with worn or wet fingers, which is a real issue for construction, kitchen, housekeeping and loading staff. Card readers avoid that problem but let one person punch for another if cards are shared. Face-reading terminals avoid both issues at a higher price and need steady lighting. Whatever you pick, check four practical points: how many users the device holds, how it sends punches (pushed over the network as they happen, or downloaded as a file), whether it keeps working on battery during a power cut, and whether it is built for dust or rain if it will sit at an open gate.

Work out how many devices you need

Size devices for the busiest minutes of the day, not the daily total. A plant with 300 workers on the morning shift who arrive between 5:45 and 6:00 am needs all 300 punches inside 15 minutes. If one punch, including the odd retry, takes about 4 seconds, one device handles 15 punches a minute, or 225 punches in 15 minutes. That is not enough for 300 people. Two devices handle 450 in the same window, and a third leaves headroom for a breakdown or a new batch of contract workers. Place them so the queue does not block the gate or spill onto the road outside.

Consent, data care and fallbacks

Fingerprint and face data are personal and sensitive. Tell employees in writing what is captured, why, where it is stored and who can see it, and take their written consent at enrolment. Keep templates only as long as needed and delete them when an employee leaves. Check the data protection obligations that apply to your company before rollout rather than after a complaint.

Every biometric setup needs a fallback for the day a finger will not read or the device is down. Decide it in advance: a supervisor's register signed and passed to HR the same day, or punches recorded by HR with the reason noted. Without a written fallback, missing punches become month-end disputes that nobody can settle from memory.

Getting punches into attendance and payroll

A biometric machine only records punches. Attendance still needs shifts, grace, breaks and leave applied to those punches, and payroll needs the finished paid days. The weak point is usually the link between the device and the attendance system. Use the employee code as the user ID on every device so punches match the right person, keep device clocks in sync, and remove duplicates when someone presses twice. In ZeniaHR, devices that push punches over ADMS (iclock), Excel attendance imports and eTimeOffice sync all feed the same punch stream, and duplicates within 60 seconds are dropped.

Step by step

1. Count punches in the busiest window. For each gate and shift, count how many people arrive and leave in the peak 15 minutes. This number, not total headcount, decides how many devices you need.
2. Pick devices and fix placement. Choose the device type for your workforce and mount each unit at the entry people actually use, under cover, with power backup and a network point nearby.
3. Use employee codes as device IDs. Enter each person's employee code as their user ID on every device. Punches then match employee records without a lookup sheet that someone has to maintain.
4. Enrol staff with consent. Enrol two fingers per person, or a card or face as your device needs, after the employee signs a consent form. Test each enrolment with a live punch before the person leaves.
5. Connect devices to attendance. Set each device to push punches over the network, or schedule a daily file export. In ZeniaHR, ADMS push devices and Excel attendance imports land in one punch stream with web, app and kiosk punches.
6. Run parallel with the register for a month. Keep the old register for one month and compare daily totals. Differences point to enrolment gaps, wrong user IDs or devices whose clocks are out of sync.
7. Write the fallback process. Decide what happens when a finger fails or a device is down: a supervisor's register passed to HR daily, and punches recorded by HR with a reason.
8. Check clocks and enrolments monthly. Compare device clocks with a phone clock every month, delete leavers from the devices, and enrol joiners on their first day so they are never without punches.

Frequently asked questions