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In /de.crease of Deadly accidents per distance × costs of avaliable free speed

Dear Douglas,

I attach two papers which might shed some light over your question.

Sincerely,

Article Multi - criteria decision - making model for assessing the s...

Article Occupational Risk Index for Assessment of Risk in Constructi...

- Number of near misses reported

Dear Dough,

Measuring safety performance is a broad topic and depends on your objective, you can find several metrics. In CII, we classify safety indicators into two categories: lagging and leading. Lagging indicators focus on safety outcomes that can be measured after an accident happens. Some major examples in this category are:

OSHA RECORDABLE INCIDENT RATE - a mathematical calculation that describes the number of employees per 100 full-time employees that have been involved in a recordable injury or illness.

Incidence rate = (Number of injuries and illnesses X 200,000) / Employee hours worked

LOST TIME CASE RATE – a mathematical calculation that describes the number of lost time cases per 100 full-time employees in any given time frame.

LTC Rate = (Number of Lost Time Cases x 200,000)/ Number of Employee Labor Hours Worked

SEVERITY RATE – a mathematical calculation that describes the number of lost days experienced as compared to the number of incidents experienced.

SR = (Total number lost workdays)/(Total number of recordable incidents)

DART RATE - a mathematical calculation that describes the number of recordable incidents per 100 full time employees that resulted in lost or restricted days or job transfer due to work related injuries or illnesses.

DART Rate = (Total Number of DART incidents x 200,000)/( Number of Employee Labor Hours Worked)

There are several limitations related to lagging indicators. First, they are collected after an incident and we cannot use them to provide early warnings for workers. Second, accidents are infrequent events and it is possible to not have an accident in a project, even though the safety performance is not satisfactory. Third, collecting number of hours in all projects would be difficult for outside researchers. To address these problems, many people suggest to use leading indicators. Some of the main active measures are:

- Number of behavior based safety (BBS) observations received versus the target number of BBS observations by project/month

- Number of quality JSA's as a percentage of the total number of JSA's reviewed by project/month

- Total number of Leadership walk-around's versus the total expected by project/month

- and so many others …..

While leading indicators are better in providing early warning when something is going wrong, large majority of contractors do not record them. In addition, some of these measures are subjective.

 If you are trying to measure impact of policy changes on safety outcomes, I would suggest to use leading indicators, since they capture the essence of safety performance much better than lagging indicators.

 Some of the good sources are:

 -  Hinze, J., Thurman, S., and Wehle, A. (2013). “Leading indicators of construction safety performance.” Safety Science, 51(1), 23–28.

 -  Hallowell, M., Hinze, J., Baud, K., and Wehle, A. (2013). ”Proactive Construction Safety Control: Measuring, Monitoring, and Responding to Safety Leading Indicators.” J. Constr. Eng. Manage., 139(10), 04013010.

 -  CII Report: https://www.construction-institute.org/scriptcontent/more/284_1_v1-1_more.cfm

I hope I answered your question, please let me know if you have any other question.

All the best,

Behzad

Tel: (402) 472-5504

Email: [email protected]