Risk Analysis Techniques in Product and Process Design

1.Risk Analysis, Safety Analysis

A risk analysis project is typically completed in the following steps:

We use standard methods such as: Hazard Analysis, Potential Problems Analysis (PPA), FMEA and Hazop, even PSA (Probabilistic Safety Assessment).

Hazop-SIL-LOPA: Hazop (Hazard and Operability Study) is often completed with SIL analysis/ classification and LOPA (Layers Of Protection Analysis). In LOPA the residual risks are calculated and proper protection levels suggested for risks identified in Hazop. LOPA is based on standard EN 61511 (Functional Safety standard for process industry). AL Safety Design has developed a special tool for Hazop-SIL-LOPA analyses, which can be used in risk analysis sessions.

Functional Safety and SIL (EN 61508, EN 62061, EN 13849), see our 'Safety Conformance' page.

PSA, Probabilistic Safety Assessment: Today it is very important to analyze and compare risks with generally acceptable risk levels in society. PSA methods (developed in nuclear industry) with probability calculations can be applied to conventional systems to prove the acceptable safety level of the technology. The methods include Fault Tree Analysis and Event Tree Analysis.

2.Risks in Design and Manufacturing: Design FMEA, Process FMEA

The manufacturing errors and assembly mistakes are the main cause of the product failures during warranty period. For a manufacturer this means increased warranty costs and customer dissatisfaction.

Process FMEA: Process FMEA (=Failure Modes and Effects Analysis) is a very effective tool in analyzing Manufacturing and Assembly processes. It was first introduced by American automotive industry in connection with the QS-9000 quality standard (now ISO/TS).

Design FMEA: The P-FMEA analysis can be complemented with the D-FMEA method (Design FMEA) studying the product failure modes and potential effects in detail.

3.RAM Analysis and Reliability Modelling

RAM model predicts potential production losses caused by subsystems and components. RAM analysis pinpoints the system 'bottlenecks' and related subsystems/ equipment ('Top 10 list'). RAM analysis is the first step in RCM or LCC analysis. (RCM = Reliability Centered Maintenance, LCC= Life Cycle Costs).

We have developed effective methods and tools for

The RAM results are calculated and used when different system alternatives are compared, supporting the design project to optimized process and system structures. For the RAM data used in calculations the generic data sources are used or a RAM data collection campaign is arranged.

We have modeled power plants, chemical processes, wind power, fuel cells, bio power, oil refineries, paper machines, heavy machinery, train systems, control systems etc.