EASA Safety Performance Indicators: What the Rules Say, and a Worked SPI Set

Fourteen reports, compared with what?

The safety review board pack at ExampleMRO has one slide on safety performance: 14 internal safety reports this quarter, up from 11. The accountable manager asks whether that is good or bad. Nobody can say. The number has no denominator, no target and no owner.

EASA's answer is in the management system rules. For Part-145 organisations and CAMOs, the AMC describe safety performance monitoring and measurement as the process that verifies safety performance against the safety policy and objectives, and list "evaluation of safety performance indicators" as one route to continuous improvement. For complex air operators, the AMC list safety reporting, studies, reviews, audits and surveys. Of the domains compared here, only the aerodrome implementing rule names both safety performance indicators and targets. None of these texts gives you a list of SPIs, a target value or an alert-level method. Choosing them is the organisation's work, and this guide shows how.

Key facts

• An SPI is "a parameter used for monitoring and assessing safety performance"; a target is "a planned or intended objective for complying with safety performance indicators over a given period of time".
• 145.A.200(a)(3), CAMO.A.200(a)(3) and ORO.GEN.200(a)(3) require risk mitigation "and verify their effectiveness". None uses the word "indicator".
• The Part-145 and Part-CAMO AMC compare performance "with the safety policy and the safety objectives" and list "evaluation of safety performance indicators" under continuous improvement.
• The complex-operator AMC lists safety reporting, studies, reviews, audits and surveys.
• For aerodrome operators, ADR.OR.D.005(b)(5) refers to "the safety performance indicators and safety performance targets of the safety management system".
• EASA guidance for complex air traffic services providers splits indicators into leading and lagging.
• The Part-145 safety review board monitors "the safety performance against the safety policy and objectives". No text quoted here sets a review frequency, a target value or an alert-level method.

What EASA means by an SPI and an SPT

The definitions sit in the Basic Regulation.

The indicator is the parameter: a count, a rate, a percentage. The target is the value you plan to reach. Safety performance is defined by both, so a parameter alone, like the ExampleMRO slide, says nothing about performance. See the Article 3 rule page and the term pages for safety performance indicator and safety performance target.

Part-145: safety performance monitoring under 145.A.200

The rule never says "indicator". It says verify.

An SPI shows that verification in numbers. Point (b) is why a small line maintenance organisation and a large base maintenance organisation need different sets. See the 145.A.200 rule page.

Three things follow. Each SPI should trace to a safety objective, because that is its yardstick. The list is proportionate, so a short set is a legitimate answer. And SPIs sit under continuous improvement, beside monitoring recurrence: they exist to be evaluated, not only collected. Point (d)(2)(v) can cover counts pulled straight from a maintenance information system.

This is AMC, one accepted way to meet the rule (How to Read EASA Rules explains the difference). The full AMC1 145.A.200(a)(3) includes the reviews, audits and surveys elided above.

Part-CAMO: the same structure, one integration point

A CAMO's data differ (repeat defects, deferred items), but the logic matches Part-145. Point (d) matters for an airline's own CAMO: its SPIs belong to the operator's management system, so review them alongside flight operations. See the CAMO.A.200 rule page and AMC1 CAMO.A.200(a)(3).

Air operators: ORO.GEN.200

The operator rule carries the same verify-effectiveness hook.

The detail is in the AMC for complex operators.

This AMC never uses the phrase "safety performance indicator". Operators still need indicators, because a trend review needs a number to trend. Point (a)(2) offers one ready-made: "an effective feedback process" can be measured, and the ExampleAir set below does. Non-complex operators have a shorter AMC on the same page. Read AMC1 ORO.GEN.200(a)(3), and Part-ORO Operations Manual and Management System for the wider system.

Aerodromes: where the rule names targets

When you read that "EASA requires SPTs", this is usually the text behind it, and it applies to aerodrome operators. A Part-145 organisation or CAMO that sets targets is choosing good practice. See the ADR.OR.D.005 rule page and its AMC1 (b)(5).

The four domains side by side

Leading and lagging indicators

EASA's clearest wording on indicator types is guidance for complex air traffic services providers. It transfers well to maintenance and flight operations.

In a maintenance organisation, CAMO or operator, the split looks like this:

Outcome indicators sit at zero most months, which is why they cannot steer. Precursors give enough events to trend. Leading indicators show whether a control is in use before it fails. Pair each precursor with a leading indicator on the same hazard. The GM is on the ATS.OR.200 rule page.

What an SPI record should contain

The rules stop at the process. The record below is good practice, not a regulatory template: it lets someone other than the author understand, recalculate and challenge the SPI.

Do not skip the normaliser. Without it, a busy month looks worse than a quiet one for no safety reason.

A worked SPI set for ExampleMRO and ExampleAir

ExampleMRO is a Part-145 organisation with base and line maintenance. ExampleAir is an air carrier with its own CAMO. All figures are illustrative.

SPI 2 is the leading partner of SPI 1: both watch tasks left incomplete across a shift change. SPI 4 measures the feedback process from the ORO.GEN.200 AMC. The 21 days is ExampleAir's own procedure, not a regulatory figure.

Running one month. In March, ExampleMRO closed 2,450 work orders and classified 3 occurrences as maintenance-induced.

3 ÷ 2,450 × 1,000 = 1.22 per 1,000

That misses the SPT of 1.0 but stays under yellow: a target miss, not an alert. Someone still decides: investigate, act, or record why no action is needed. In April, 5 occurrences against 2,380 work orders gives 2.10, past orange, and the five-day review starts.

Why the bands need care. At about 2,400 work orders a month, one occurrence moves the rate by roughly 0.4. Two events are on target, three miss it, four reach yellow, five reach orange. The whole structure is three events wide, so treat one yellow month as a prompt, not a verdict. For rare events, a trend rule (two misses in three months, say) or a rolling 12-month rate reads better. Deriving targets and alert levels from a baseline, small-number traps included, is covered in SPI Alert Levels and Targets: A Worked Example.

Reviewing SPIs: who looks and what they decide

Point (d) of the same AMC lets an organisation work without a formal board where its size and complexity justify it, subject to a risk assessment and the competent authority's agreement; the board's tasks then go to the safety manager. AMC1 CAMO.A.200(a)(1) and the complex-operator AMC1 ORO.GEN.200(a)(1) give the board a similar list. None says how often, so set a cadence in your procedures: monthly data, a fixed board review, and a yearly review of the set itself, plus one whenever the organisation changes.

The decision matters more than the chart. For each miss, record the number, the owner's conclusion and the next step. "Noted" is not a conclusion. A no-action decision carries a written reason, so the next board sees whether the same reason keeps returning. When an SPI points to events that need analysis, Occurrence Analysis and Follow-up in the SMS covers the loop. The Part-145 text is at AMC1 145.A.200(a)(1).

Five ways an SPI set stops working

• Counts with no normaliser. Fourteen reports means nothing until you know per what.
• Borrowed targets. Another organisation's target reflects its fleet and reporting culture, not yours.
• Silent formula changes. If counting changes in July, mark July, or the trend line lies.
• Only lagging indicators. By the time a precursor moves, the control has already failed.
• Acknowledged, never decided. Noting an alert without a decision is not monitoring.

The hazards your SPIs watch come from hazard identification and risk assessment, the next guide in this series: hazard identification and safety risk management. The public SMS hazard library is a starting list.

Doing this in Avioverse

Safety Performance Indicators has two tabs, Tracked SPIs and Reference library. Add SPI offers Choose from reference library or Create a custom SPI. Each library definition shows its source, either derived from the UK CAA's CAP 3114 example SPIs or written by Avioverse, and the library says: "Alert & action thresholds aren’t prescribed — they depend on your fleet and baseline."

Setup runs in three steps: Definition, Tracking, Review. In Definition you answer What are you tracking? (a count, a rate, a percentage and so on), pick or create the measures and choose Show per, such as per 1,000. Try a sample calculation tests the formula without saving. In Tracking you Set a Safety Performance Target, choose Lower is better or Higher is better, add a Yellow alert (optional) and Orange alert (optional), set Target applies from, and in a team workspace pick the Responsible person who receives alerts.

Each month you Enter monthly data for a completed month and Avioverse calculates the value. A missing measure or a division by zero leaves the month unassessed. A miss shows SPT exceeded, or Yellow alert or Orange alert if it also crosses those lines. Optional trend rules flag consecutive or repeated misses. With no SPT, nothing is flagged.

A flagged month waits for a person. Acknowledge records that you saw it and does not close it. Create task adds a linked "Investigate…" task; completing it resolves the exceedance. Reviewed — no action required needs a written reason. Changes apply from a month you choose, with earlier versions under Saved versions. Each SPI exports to PDF and Measurement history (CSV).

The assistant can set up an SPI and, once you approve the preview, import monthly values from a pasted table (or an attached file on a paid plan). It cannot set targets or alert levels. Values come only from what you enter or approve; indicators, targets and responses stay your decisions.