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Accident Frequency Rate

Rose 8 years ago   Reply
Hi I want to start monitoring the accident frequency rate for our company. I have been given a couple of different ways to do this, usually by multiplying by 100,000. But somehow this confuses me. The book I have been using which is a NEBOSH book states a formula (total number of accidents/number of persons employed x 1000)Simple, but is it enough?. Do I need to have labour hours in here? Can anyone give me a simple formula to work this out?

Ian Simms 8 years ago   Reply

As a Client we expect our contractors to report AFR to us using the
following formula:

Accident frequency rate- The overall accident / incident statistics for the
Contractor, but excluding any shareholders of the Contractor. Where the
Contractor is not a holding company these statistics shall include the
statistics for the holding company and all subsidiary companies. Where the
Contractor is a holding company these statistics shall include the
Contractor and all subsidiary companies, all as defined by s.736 of the
Companies Act 1985.

The accident frequency rate will be calculated as follows:
NRA / ANE x 100,000
· NRA is the number of reportable accidents in the previous 12 months.
· the number of reportable accidents is defined as the total number of
RIDDOR accidents (as defined by the Health and Safety at Work Act), across
all the Contractorâ??s customers [including its holding company and/or
subsidiaries]; and.
· â??In the previous 12 monthsâ?? shall mean the previous 12 month period
relevant to each current month.
· ANE is the average number of employees over the previous 12 months
which shall take into account the following:
- Where subcontractors provide part of the service the number of
subcontract workers should be included.
- Head office and management staff should be included.
- The Contractor shall take a reasonable view on the use of
part-time staff and sub-contract workers when calculating the
number of employees.


Ian Simms

Royal Mail Group Limited registered in England and Wales registered number
4138203 registered office 3rd Floor, 100 Victoria Embankment, London, EC4Y

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Rohit 8 years ago   Reply
Average number of personnel, this varies drastically. sometimes we have 300 personnel involved for 90 days followed by 110 for another 2 months in this was what is the acurate way to assess Average Manpower ?

Please advise on above.

Essam 8 years ago   Reply
I'm using the following Formula

AFR=Number of LTA* 1,000,000 / Total Mna-hours worked
Keith greenwood 8 years ago   Reply

There are many different multipliers used to calculate the accident
frequency rate

To determine the accident frequency rate, I use the number of Lost time
incidents or (recordable cases) x 100,000/the total number of man hours

This approximately equates to the number of hours an individual works in his
life time, based on a 40 hour week.

As a result the safety selling point becomes a personal factor and not a
statistic, since the frequency rate calculated is also the number of lost
time accidents, an individual is likely to have in his working life time.

As an aside, 200,000 hours can be use to the same effect if the working week
is extended to 80 hours



kiran 6 years ago   Reply

Dear Sir,

Please share Safety Activities & new  Safety & EHS related ideas in different organisation.

Truely Yours.

Kiran Karande.

Essam 8 years ago   Reply
Accident Frequency Rate

This can be calculated for any time period (month, year):

No. of lost-time accidents x 1000,000 / No. of man hours worked

This gives a measure of the no. of accidents per 1000,000 hours worked.

And you should also monitor the sevirity rate
Severity Rate

Total no. of days lost x 1,000 / Total no. of man-hours worked

This measures average no. of days lost per 1000 hours worked
ESS 8 years ago   Reply
The formula you have found is for Incidence rate rather than frequency rate which is where the time element comes in.

The HSE have described both of these in their publication HSG 65 Successful Health and Safety Management, Appendix 6.

Accident Frequency Rate is [(Number of injuries in the period)/(Total hours worked during the period)] x 1,000,000. ie the number of injuries per million hours worked.
Annual Injury Incidence Rate is [Number of reportable injuries in financial year)/(average number employed during the year)] x 100,000. ie the number of injuries per 100,000 workers.

A lot of larger companies have their own way of allowing for numbers of employees to be included and hours worked to make it representative. These methods are devised to suit their own circumstances, which may include for instance an allowance for the average time a delivery driver is on site.

It also depends what you are comparing it with. If it is just for internal use it doesn't really matter, but needs to be the same each year. If you are going to compare figures outside your organisation eg with a trade body, it is best to follow common guidelines otherwise you are comparing apples and pears.

Hope that helps

Steve 7 years ago   Reply

I am following the formulars for AIRS & AFRs and they seem pritty High for last year, ie 3 reported out of 375 employees, based on 720000 hrs total.  I get a AIR or 800 and AFR of 4.1 . Am I right or have I gone off track and what do I do with these figures in the past they have been 1.1's ect

AFC1903td 6 years ago   Reply



You are correct in your calculations. I am just back from the US after having worked there for 5 years and hav ebeen used ot the OSHA reporting structure so to come back and us the Uk method and start seeing numbers in the hundereds and thousands is misleading.




David Bird 6 years ago   Reply

Base it on 100,000hrs (which is what anybody would approximately work in their life) this helps in explaining the figures to employees in a more friendly/ understandable manner.
You can either do it weekly, monthly or whatever.

The formula is:

(Number of accidents x 100,000 hrs) / hrs worked. your example 60 employees would work 140400 hrs in the year (45hrs per person per week) and you have 5 reportable accidents.

(5 x 100,000) / 140400 = 3.56. your reportable accident rate for the year based on 100,000 hrs worked is 3.56, which means that an employee working in your company is likely to have 3.56 reportable accidents during their life if they worked there all their life.

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