Risk Assessment of machines, plants and electrical devices
Manufacturer of machines and plants, as well as manufacturers of electrical devices must determine, which hazards and risks are associated with their products. This legal requirement can be found in different EU directives, such as:
- Machinery Directive (MD) 2006/42/EC
- Low Voltage Directive (LVD) 2014/35/EU
- Pressure Equipment Directive 2014/68/EU
- ATEX Directive 2014/34/EU
- ...
Risk Analysis: Voluntarily or prescribed by law?
Machinery Directive 2006/42/EC
It´s often assumed that performing a risk assessment is voluntary. The Machinery Directive 2006/42 / EC clarifies in Appendix I that the risk assessment is a mandatory requirement:
The manufacturer of machinery (…) must ensure that a risk assessment is carried out in order to determine the health and safety requirements which apply to the machinery.
Low Voltage Directive 2014/35/EU
The new Low Voltage Directive 2014/35/EU (LVD) also makes manufacturers fully responsible:
The manufacturer shall establish the technical documentation. (…) and shall include an adequate analysis and assessment of the risk(s).
Risk Assessment according to other guidelines
The guidelines of the so-called New Legislative Framework require the implementation of an appropriate risk analysis and assessment.
Strategy for risk assessment
Different terms such as risk analysis, risk evaluation or risk estimation are used in connection with risk assessments. These terms represent different steps in the process of risk assessment.
The process of risk assessment for machines and systems is described in the international standard EN ISO 12100:
| PROCESS STEPS | designation |
|---|---|
| a) Define the limits of the machine, including its intended use and reasonably foreseeable misuse; |
|
| b) Identifying hazards and associated hazardous situations; | |
| c) Assessing the risk for each identified hazard and hazardous situation; | |
| d) Assessing the risk for each identified hazard and hazardous situation; | Risk Evaluation* |
| e) Eliminating the hazard or reducing the risk associated with the hazard by means of protectives measures; | Risk Reduction |
*The process steps Risk Analysis and Risk Evaluation together forms the Risk Assessment.
Tasks of designers and engineers
The risk reduction methods has to be fulfilled by designers in a fixed order. This legally prescribed sequence can be found both in the Machinery Directive as well as in the EN ISO 12100. CENELEC Guide 32 offers corresponding information for products according to the Low Voltage Directive. The different documents only differ in terminology:
| EN ISO 12100 | MACHINERy Directive 2006/42/EC | CENELEC GUIDE 32 |
|---|---|---|
| Inherently safe design | Integration of safety in the design and construction of the machine | Intrinsic safety measures |
| Technical protective measures and / or additional protectives measures | Taking the necessary protective measures against risks, that cannot be eliminated | Technical protective measures and additional protectives measures |
| User information | Instruction of users (…) | User information |
Common mistakes in practice
The legally required integration of safety into design / construction processes is not observed. Risk assessments are carried out too late or not at all!
Risk assessments are made too late
Risk assessments are carried out by one (1) person after the machine has been built, if at all. This procedure does not meet the legal requirements, but usually costs a lot of money! Every person involved in the product development process is obliged to participate in the risk assessment as part of their activities. Hazards are identified early on and suitable measures are defined immediately. Eliminating hazards at the time of commissioning or in operation can be very expensive!
The CE coordinator does it (must do it)
All persons involved in the development processes rely on a CE representative or CE coordinator who is not provided for by law. These people can coordinate, organize or support, but are not responsible for the operational implementation of risk assessments in projects!
Expensive protective devices instead of inherently safe designs
The cost-saving inherently safe designs are not used. Instead, expensive protective devices are installed that would not be necessary in this form for the identified hazards and the assessed risk. A qualitative risk assessment can help to avoid unnecessary and cost intense safety measures!
Indications of residual hazards instead of technical solutions
Notes on residual hazards in the operating instructions are chosen instead of technical solutions. Numerous judgments show that compliance with the order required by law is particularly important in order to avoid liability cases.