Most registration errors don't occur because an employee "does something wrong", but because the registration doesn't match what's recorded in other NSSO systems. Check In and Out at Work (CIaO) automatically checks every check-in or check-out against your Dimona declarations, Limosa notifications, and the Declaration of Works. If that link doesn't match, an error code is generated — regardless of whether anything actually went wrong in practice.
Late or missing Dimona declaration
The most common cause. A Dimona declaration must be submitted before the start of the shift. If an employee is scheduled at the last minute, or a schedule changes the same morning, they may check in before the Dimona declaration has been processed — which generates an error code, even though the employee is working entirely legitimately.
Shift changes and last-minute schedule changes
When an employee replaces a colleague who is absent, the new registration is sometimes not linked to an updated Dimona or Declaration of Works entry. An employee who switches between two sites within the same day can also cause duplicate or incomplete registrations as a result.
Missing or incorrect Limosa notification
For foreign workers, an active Limosa notification must be present at the moment of registration. If it expires, or is still missing, the check-in is automatically flagged as deviating.
Declaration of Works not (correctly) submitted
When working with subcontractors, the contractor-subcontractor-site relationship must be correctly declared. A late Declaration of Works, an incorrect site address, or a subcontractor not linked to the right main contractor, leads to error codes that often only become visible at the main contractor's level — not with the subcontractor itself.
Duplicate or missing check-in/check-out
An employee who accidentally checks in twice (for example due to a weak signal and a repeated attempt), or who checks in but forgets to check out, causes an incomplete registration that the NSSO considers deviating.
Location and technical issues
A missing GPS location, a registration transmitted too late due to a weak internet connection, or a site address the system doesn't recognize, can all cause technical error codes unrelated to any human error.
What can you do about it?
Most of these causes can't be prevented with extra checks on site itself — the error arises in the link between systems, not in the check-in itself. What does help: keeping your Dimona, Limosa, and Declaration of Works entries timely and consistent, and regularly checking which error codes are accumulating before an inspection does it for you. CIAO Assist makes these linking errors visible as soon as they arise, so you can correct them at the source.