Safety metrics techniques

The safety professional has many tools and techniques available to establish a safety metrics program, collect data, evaluate performance, and make decisions based on 

---

There are additional safety metrics techniques that can be used to assess the safety climate in an organization in terms of the organization s management, employees, and environment. The environment includes the physical environment, the equipment, and the interfaces between the workers and the work environment. Each area provides the safety professional with additional information to determine if the safety performance in the organization is at an acceptable level. 

Consider the operations that will be monitored when selecting metrics. Selected metrics should reflect the most likely problem areas that may arise for the specific operating situation and the available staff to maintain or monitor metrics. Techniques are described and recommended in various publications, such as the U.K. Health and Safety Executive (HSE) publication HSG254 (see Section 4.5.3). Three hypothetical examples are described below ... 

Markov models are a reliability and safety modeling technique that uses state diagrams. These diagrams have only two simple s)rmbols (see Figure 5-17) a circle representing a working or a failed system state and a transition arc representing a movement between states caused by a failure or a repair. Solution techniques for Markov models can directly calculate many different metrics compared to other reliability and safety evaluation techniques (Ref. 9). 

Reliability and safety metrics can be calculated using matrix techniques from this P matrix. 

Janicak, Christopher A., Safety Metrics Tools and Techniques for Measuring Safety Performance, Government Institutes, 2009. 

Today s safety professional has moved beyond the standard measurement of safety performance in terms of the number of accidents or injuries and recordable injury and illness rates. More sophisticated techniques that involve safety performance measurement systems, ongoing tracking of results, and continual improvement processes have replaced the early measurements. While today s safety metrics still include accident and illness performance, they also encompass behavior-based safety, safety program implementation performance, and insurance costs and losses. 

In order to develop and maintain a safety metrics program, various resources must be identified. These resources include data sources and measurement techniques. If a more traditional approach to measuring safety performance is utilized, such as accident and injury rates, the data should be available and if not, part of the metrics program should involve the procedures for collecting the data and collating it at a central location for analysis. 

In order to monitor the success of a safety program, both a successful auditing program and quality safety metrics are needed because audits are another technique used in the evaluation and data collection process of the program. An audit or inspection is the monitoring function conducted in an industrial organization to locate and report existing and potential hazards, or man-environment systems or conditions, that have the capacity to cause accidents or illnesses in the workplace (Petersen 1998). 

Techniques used in systems safety frequently have specific goals and areas that they can address. For example, some techniques are used to analyze the hardware and equipment aspects of the system while other techniques are used to assess the human aspect. From a safety metrics standpoint, systems safety techniques can be used to identify areas for improvement in the organization. While there are hundreds of system safety techniques available, some of the more commonly used are Fault Tree Analysis (FTA), Procedure Analysis, Failure Modes and Effects Analysis, and Root Cause Analysis. 

Safety metrics tools and techniques for measuring safety performance / Christopher A. Janicak. p. cm. 

When safety professionals first began using safety metrics, they routinely measured safety performance in terms of accidents and losses. However, over the years, as the safety profession has become more sophisticated, so also have the techniques used to measure its execution. A successful program should include combinations of various types of performance measures. As with any data collection, the safety professional must also keep in mind the validity and reliability of the performance measures. Only with accurate and consistent data can the proper conclusions be reached, and the necessary control strategies implemented. 

This book provides safety practitioners with information and tools that can be used to develop and implement a safety metrics program. Techniques are presented to assist the safety professional in implementing a safety metrics program, establishing performance measures, analyzing data, and determining the need for corrective action. 

Petersen (2005) included an 18-page appendix on Statistical Process Control in Measurement of Safety Performance. Janicak (2010) has a 30-page chapter on Run Charts and Control Charts in Safety Metrics Tools and Techniques for Measuring Safety Performance. Other authors in years past have suggested the use of control charts to track safety performance. Yet, the subject does not appear in the current safety-related literature. 

V-Nitrosodiethanolamine has been found in many complex matrices such as cutting and grinding fluids and cosmetics. Analysis for V-nitrosodiethanolamine is complicated by the matrix and a clean-up technique with derivatization is typically required before quantitation of the analyte to achieve adequate sensitivity and selectivity. Ammonium sulfamate may be added to the sample to prevent the artifactual formation ofV-nitrosamines. Derivatives of V-nitrosodiethanolamine have been prepared by acylation, trifluoroacylation, trimethylsilylation and methylation. The derivatives have been analysed by gas chromatography using flame ionization and mass spectro-metric detectors (Occupational Safety and Health Administration, 1990). 

One documented method uses process safety barriers identification for metrics selection. This concept uses a combination of lagging and leading indicators associated with process safety barriers and incident escalation controls to evaluate the process safety system performance. The basis for this method is documented in the U.K. Health and Safety Executive (HSE) publication HSG254 and illustrated by Figures 4.1-4.3. The strength of this technique arises from using the combination of indicators that provides multiple perspectives for judging the surety of a barrier or escalation control. For example, this basic concept was adopted and modified by BP to focus upon three information sources to assess key control barriers as summarized below ... 

When implementing a metrics system, it is important to ensure the process safety data is reviewed for accuracy. Inaccurate data can lead to poor decisions and focus improper priority to issues. Worse, inaccurate data may focus attention away from serious performance deficiencies. The metrics system designer needs to define the methods that will be used to validate data entered into the metrics system. There are several techniques for validating data many of the techniques have been developed through quality-based efforts and auditing methods. The following is not a detailed how to for developing a validation method, but rather introduces topics for further research. 

As discussed in Chapter 7, metrics should be tailored for the intended or required improvements. The metrics communication plan should be designed to deliver appropriate information to intended audiences so they can make good decisions. This chapter discusses the needs and techniques for communicating process safety results across the organization. Topics include selecting the appropriate metrics to share and techniques for establishing the communications strategy. 

Using success stories and case histories is a common technique to demonstrate the value of a process safety and metrics system. Illustrative examples are easy to understand and demonstrate the value of a reliable process safety system. Metrics provide the means to shape such stories and explain the improvement progress and benefits for all members of an organization. 

Preference estimate Multiple regression techniques on the survey data are used to estimate the relative importance of each attribute level. CA allows estimation of the relative importance of each attribute such that the utility differences and values across all profiles can be evaluated. Several BR metrics can be derived such as minimum acceptable benefit for a given level of risk and maximum acceptable risk for a given level of benefit, net effective margin, and net safety margin, to be used in BRA. 

A new approach to evaluation of active safety is then developed in Chap. 3. The process, including information needed, is described, and the prerequisites are defined. In detail, accident scenarios, configuration of a functional demonstrator of a preventive pedestrian protection system, and the simulative technique required are described. An introduction of a metric for the quantification of the change in safety rounds up the method. 

In order to acmally obtain this residual risk level, it is imperative to assure that these measures are effective. Then, in order to monitor the risk and to demonstrate that it is controlled, it is necessary to verify and validate risk mitigations, usually through classical software testing. Indeed, verification may comprise many techniques and procedures such as plain document review, code reviews, code metrics analysis, etc. After all, testing is one of the foundations of safety and reliability. 

---