Injury rate calculator

Ask three safety managers in three provinces for “our injury rate” and you will get three numbers that cannot be added together. That is not sloppiness. Canada does not have one workers’ compensation system; it has one per province and territory, plus a federal layer, and each of them defines its own population, its own denominator and its own publication schedule.

This calculator does the arithmetic for the figure your board publishes, and for the 200,000-hour rates your prime contractor keeps asking for. The rest of this page is about which is which, because putting the wrong one in a prequalification package is a more expensive mistake than a rounding error.

Which rules apply to you

Before any rate, the jurisdiction question. Roughly 6 % of the Canadian workforce is federally regulated — interprovincial and international transport, railways, airlines, marine, banking, telecommunications and broadcasting, grain, uranium, the federal public service, and certain First Nations community services. Those workplaces follow Part II of the Canada Labour Code and the regulations under it.

Everyone else follows a provincial or territorial act — the Occupational Health and Safety Act in Ontario, the Loi sur la santé et la sécurité du travail in Quebec, the Occupational Health and Safety Act in Alberta, the Workers Compensation Act and the OHS Regulation in British Columbia, and so on across the remaining ten.

This matters here for one reason: the health and safety act and the compensation board are two different things. The act tells you what to do and who inspects you. The board pays the claims and publishes the rate. A federally regulated employer still deals with a provincial board for compensation, because there is no federal one.

The number every board publishes

Whatever it is called locally, the headline figure is the same shape:

(lost-time claims × 100) ÷ full-time equivalents

Per 100 workers. Not per million hours, not per 200,000 hours. The names differ:

Quebec’s own regulatory language is French, and its instruments keep their French names: the CNESST, the LSST, the RSST, the programme de prévention. Translating them invents documents that do not exist.

The numerator is an insurer’s decision, not a safety measurement

This is the single most useful thing this page can tell you, and it is the thing most in-house dashboards get wrong.

A lost-time claim, in the CCOHS wording, is “an injury where a worker is compensated by a Board/Commission for a loss of wages following a work-related injury.” Read that again: compensated. Three consequences follow, and none of them is intuitive.

It is decided weeks or months after the event. An injury in November may be adjudicated in February. Your incident log knows about it immediately; the rate does not.

A denied claim is not in the rate. If the board decides the injury was not work-related, it leaves the statistic. It stays in your own records, and it must — your incident investigation obligations do not run on the board’s adjudication.

A claim that resolves without lost wages is not in it either. Health-care-only claims, modified duties that avoid a wage loss, first aid: all real events, none of them in the published rate.

The practical effect is that the board’s rate is a lagging, filtered measure of what happened to you, and your internal count will almost always be higher. That is not a discrepancy to reconcile. It is two instruments measuring two different things.

The denominator is estimated from payroll

You do not report hours to your board. You report insurable earnings, and the board converts them into person-years — full-time-equivalent workers. That conversion is theirs, not yours, and it means two employers with identical headcounts and different wage structures do not have identical denominators.

It also means that the denominator in your calculation here is not the denominator the board used. If you want your rate as the board computed it, take the board’s own figure from your account rather than recomputing it. Use this calculator to understand the shape of the number, to track it monthly between board statements, and to test what a claim would do to it.

The 200,000-hour rates, and where they come from

If you work in construction, energy, or anywhere with a Certificate of Recognition programme or contractor prequalification, you have been asked for a TRIF — total recordable injury frequency:

(recordable injuries × 200,000) ÷ hours worked

200,000 hours is roughly 100 people working a full year, so the result reads as “recordable injuries per 100 workers per year”. A severity rate is built the same way, with days lost in the numerator.

Two things to be clear about.

It is not law anywhere in Canada. No provincial act and no part of the Canada Labour Code requires it. It is a contractual and industry convention, used in prequalification, in owner scorecards, and in COR programmes. That does not make it unimportant — losing a bid over it is very real — but it does mean nobody official publishes a figure for you to compare to.

Its definitions are imported. “Recordable” comes from a United States recording rule: anything beyond first aid, whether or not time was lost, plus restricted work and job transfer. Canada has no such recording standard, so what counts as recordable is decided by whoever wrote the contract. Two contractors reporting a TRIF to the same owner may not be counting the same events, and the owner is rarely in a position to notice.

If you report a TRIF, write your recording rule down and attach it. It is the only way the number means anything to the person reading it, and it is the only defence you have when a competitor’s figure is suspiciously low.

What the rate does not tell you

It is not a measure of safety, it is a measure of accepted claims. Every mechanism that reduces claims without reducing harm pushes the rate down: aggressive modified-duty programmes that avoid wage loss, claim challenges, and — the one nobody says out loud — a workforce that has learned not to report. The moment a rate becomes a bonus target, it starts measuring reporting behaviour instead of risk.

It is unstable at small size. With 40 person-years, one claim is a rate of 2.5 and zero claims is a rate of 0. There is no value in between. Below a few hundred person-years, an annual rate is a weak signal and a monthly one is noise. The Alberta statistics say this plainly: rates based on a small number of person-years are too volatile for valid comparison over time.

It says nothing about occupational disease. Noise-induced hearing loss, musculoskeletal disorders, chemical exposure and psychological injury are handled on entirely different timescales, and in most workplaces they represent more real harm than the lost-time claims do.

It is blind to what almost happened. The events that had no consequence are the ones that predict the ones that will, and no rate on this page can see them.

Comparing your rate

Compare to your own board, in your own rate group or classification unit. Every board publishes rates by industry classification; that is the only comparison with any meaning. A provincial average across all industries tells you nothing about a sawmill.

Do not compare across provinces. Coverage differs — which industries are mandatory, which are optional — and so do adjudication practices. A lower rate in one province may reflect a narrower definition of a compensable injury rather than a safer workplace.

Do not convert a European figure. This comes up constantly in companies with a European parent, and the arithmetic is always wrong:

• A French taux de fréquence counts accidents with any lost time at all, per million hours worked. Different numerator, different denominator, different base.
• A German 1000-Mann-Quote only counts accidents causing more than three days of incapacity, per 1,000 full-time equivalents. An accident that costs two days does not exist in that figure.
• A Spanish índice de incidencia now runs on a base of 100,000 affiliates, and it changed base recently.

There is no factor that converts one into another, because the populations differ, not the units. A group that consolidates these into a single global figure has built an average of four different questions.

How your claims reach your premium

The rate itself does not set your premium. Claims costs do, and every board runs some form of experience rating: your own claims history moves your rate relative to others in your class. Ontario’s WSIB, for example, sets a class rate from the industry’s risk profile and then places each employer in a risk band reflecting its own experience, using insurable earnings, claims costs and allowed claim counts over a multi-year window. WorkSafeBC, WCB-Alberta and the CNESST each operate their own variant.

Three things generalise across all of them:

1. Cost, not count. One serious claim outweighs several minor ones. A falling claim count with rising claim costs is a premium going up.
2. A multi-year window, with a lag. Good performance this year shows up in a rate two or three years out. Presenting it to a finance director as a next-year saving sets up a disappointment.
3. The mechanics change. Boards revise their rate-setting models, and archived pages describing a superseded framework are easy to find. Check your board’s current documentation before quoting a mechanism, not a search result.

Questions that come up

Should I count injuries with no lost time?

Not in the lost-time claim rate — that is what makes it a lost-time rate. Count them anyway. The ratio of no-lost-time to lost-time events is one of the better indicators of whether people are reporting at all.

Do modified duties end a lost-time claim?

For rate purposes, what matters is whether there was a wage loss. A worker moved to suitable modified duties at full pay generally does not generate one, which is exactly why return-to-work programmes move the rate. Whether that is a genuine improvement or a measurement artefact depends entirely on whether the duties are real.

What about a claim from a previous year?

It belongs to the year of the injury for your own records, and to the board’s own attribution rules for the published rate. The two do not always agree, and the difference is one of the reasons your figure and theirs diverge.

Do I count contractors on my site?

Not in your board rate — they have their own employer and their own account. Many owners track a site-wide rate that includes every contractor on the property, which is good prevention practice and is not the same number. Name it differently, or it will end up in a report where it does not belong.

Which hours go in the 200,000-hour rates?

Actual hours worked, including overtime, excluding vacation, statutory holidays and sick leave. If contractors are in the numerator, their hours belong in the denominator. The rule that saves you every time: the numerator and the denominator must describe the same population.

Is there a target rate?

No, and be careful with anyone who offers one. A rate that only goes down is often a reporting system that has stopped working. What is worth targeting is the quality of the underlying process — reporting rate, investigation closure, action completion — none of which appears on this page.

What to keep as evidence

Whatever you publish, someone will eventually ask you to reproduce it. Keep, per period:

• The claim list: injury date, reported date, adjudication status and outcome, days lost. Adjudication status changes; record the date it changed.
• The board statement the person-year figure came from, since you did not compute it yourself.
• The hours record and its source, if you publish 200,000-hour rates, with the recording rule you applied written out.
• The scope note: contractors in or out, which sites, which jurisdiction. Three lines.

That last one is the one everybody skips and the only one that makes a multi-year series worth having. A ten-year trend calculated three different ways is not a trend — it is three short series stacked end to end, and nobody will ever know which of the breaks was an improvement.

If your method is better

This page describes common practice, sourced on the boards’ own published definitions. It is not the only defensible practice, and if you have worked out something sharper — a site-wide rate that survives an audit, a way of handling multi-jurisdictional operations, a recording rule that holds up in prequalification — that is exactly what this site exists to collect and publish for everybody else.