Over the last 10 years, many countries around the world started transitioning from prescriptive-based to performance-based building regulations. This allowed engineers to utilize performance-based analysis and design methods across a wide range of disciplines, including fire safety engineering. However, it seems that there have been some problems along the way. In country assessments of performance-based designs for fire were done in Australia, Japan, Netherlands, New Zealand, Scotland, Spain, and Sweden. In addition to the in-country assessments, a web-based survey was conducted with respondents from all over the world on the perception of the state of fire safety engineering. The results of these assessments can be found in an article by Brian Meacham in the 2018, Quarter 3 issue of Fire Protection Engineering magazine.
The in-country assessments found that while performance-based design for fire is happening in each country, it is more popular in some than in others. There are no international regulations on how these designs should be done and this research found that even within a country there is a large discrepancy in how different performance-based designs are conducted. Countries where performance-based design is more popular reported more concerns with how these designs are completed and the safety levels they achieve.
In addition to these assessments an online survey found a relatively small number of performance based designs compared to researcher’s predictions. Respondents attributed this to lack of qualified and competent fire safety engineers, lack of qualified and competent review and approval authorities, lack of regulated / required qualifications mechanisms, lack of clear performance metrics within the regulations or design guidance, and lack of verification methods for ‘real’ performance-based designs.
Overall the research found that much less performance-based design for fire was being done than initially expected. Governments are working to solve the issues that are limiting these designs. These solutions include more criteria in code, more specific guidance, and minimum competency and qualifications requirements.
Performance-Based Inspection, Testing, and Maintenance
The prescriptive approach to the tasks and frequencies for inspection, testing, and maintenance (ITM) is one size fits all, which results in some requirements being insufficient and some excessive. Alternatively, a performance-based design approach optimizes ITM based on performance requirements. An article in 2016, Quarter 4 issue of Fire Protection Engineering magazine by Ken Dungan discusses this issue.
It is first it is important to understand ITM concepts. Maintenance is any activity intended to ensure the proper operation of a structure, system, or component. Preventive maintenance are activities performed before failure or degraded performance. Predictive maintenance are activities that closely follow performance-based activities, meaning they are conducted when quantitative measures of performance are detected. Inspection is any activity intended to identify a condition detrimental to the proper operation of a structure, system, or component. Finally, testing is any activity intended to verify performance when inspection is insufficient to do so.
Planning and developing a risk-informed, performance-based ITM program includes five steps. The first is system selection and boundary definition. The second is system function and failure definition. These steps are necessary to focus the effort on attributes necessary for performance. Step three is failure modes and effects analysis (FMEA) which is essential to understanding how component failures affect system performance. The fourth step is failure mode risk assessment (risk characterization). Characterizing risk is useful for comparison and determining preventative measures as well as ITM tasks. The fifth and final step is task selection and frequency determination. This is crucial because ITM success depends on the task frequency, the ability of the task to identify the defect, and the speed and effectiveness of repair/restoration.
Taking a performance-based approach will allow better designs, more reliable and redundant components, and components more easily inspected, tested, and maintained.