Calibration status reference

A calibration requirement exposes two different kinds of status:

status is the persisted requirement lifecycle; and
due_status is a derived read state calculated by the Metra.

Do not use one as a substitute for the other. An active requirement can be current, due soon, due, or overdue.

Persisted requirement lifecycle

Value	Meaning	Due-state effect
`draft`	The recurring obligation is being prepared	`not_applicable`
`active`	The schedule is live and requires an official next due date	Derived as `current`, `due_soon`, `due`, or `overdue`
`suspended`	The schedule is deliberately paused without resetting its next due date	`suspended`
`retired`	The obligation no longer applies	`not_applicable`
`archived`	The terminal record is retained as history	`not_applicable`

Permitted lifecycle transitions

From	Permitted target values
`draft`	`active`, `archived`
`active`	`suspended`, `retired`
`suspended`	`active`, `retired`
`retired`	`archived`
`archived`	None

Initial activation does not require a reason. Suspension, resumption, retirement, and archival require a reason. Retired and archived requirements cannot be updated or restored through the normal workflow.

Retirement or archival is blocked while the requirement has open calibration events.

Requirement activation prerequisites

Activating a draft requirement requires:

an explicit initial due date;
equipment with persisted status active, quarantined, or out_of_service;
an active responsible member in the same organisation when one is selected;
the required change-status permission and current record version.

Equipment in draft, retired, or archived cannot support requirement activation. Activation copies the initial due date into the live next-due-date schedule and records initial_due_date as its source.

Resuming a suspended requirement keeps its existing schedule; it is not a new initial activation.

Derived due states

Value	Exact implemented meaning
`current`	Active, with the site-local date before the warning window
`due_soon`	Active, with the site-local date on or after `next_due_date - warning_period_days`, but before the due date
`due`	Active, with `next_due_date` equal to the current site-local date
`overdue`	Active, with `next_due_date` before the current site-local date
`suspended`	The persisted requirement lifecycle is `suspended`
`not_applicable`	The persisted lifecycle is `draft`, `retired`, or `archived`

The dashboard work queue contains active and suspended requirements and therefore filters on current, due_soon, due, overdue, and suspended. not_applicable remains available in equipment requirement views.

An active requirement without a next due date is invalid persisted state and produces an integrity error. It is not treated as current.

Site-local official calculation

The Metra uses one UTC clock instant per request and converts it into the current equipment site's stored IANA timezone. It then compares date-only values using that site's local calendar date.

For example, at one UTC instant:

Site context	Local date	Due date	Result
Site A, before local midnight	2030-03-30	2030-03-31	`due_soon` or `current`, depending on warning period
Site B, after local midnight	2030-03-31	2030-03-31	`due`

The user's browser timezone does not override this calculation. Due status is derived rather than persisted because it can change when a site's local date crosses midnight even when no record is edited.

Next-due-date sources

next_due_date_source is persisted and has these implemented values:

Value	Meaning
`initial_due_date`	The activation baseline is still official
`manual_adjustment`	An authorised user adjusted the due date with a reason
`approved_calibration_event`	An approved acceptable calibration event advanced the schedule

Changing interval or warning settings does not silently replace an already approved next due date. Due-date adjustment is available only for active or suspended requirements and is a controlled revision.