AL Safety Design logo
+358-400 899 022 • info (ät) alsafety.com

Risk Analysis Techniques in Product and Process Design

We enable our customers to develop superb technology products regarding reliability, safety and quality.
We select the most suitable methods, risk analysis tools and procedures for your project, to ensure risk identification and analysis coverage. Risk analysis improves product quality and reduces costs, such as warranty, repair, shutdown and accident costs. It also ensures product's successful introduction to competitive markets.

1.Risk Analysis, Safety Analysis

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

organize team, define analysis scope, methods and schedule
Perform a) Preliminary risk analysis (PPA etc) and b) detailed risk analyses (Hazop, FMEA etc)
Classify severity of each identified risk using e.g. a SIL number (Safety Integrity Level) or RPN (Risk Priority Number)
Compile Risk Analysis Report and Improvement Actions Report
Contact safety authorities or certification bodies for approval

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

RAM data collection and estimation
RAM (unavailability), RCM (maintenance) and LCC (cost) analysis
Planning Maintenance tasks based on RAM model
RAM reporting: Reliability and availability parameters, 'top-10 equipment, subsystems'

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.