The new AK-Praxis of the NAMUR working group 3.6.3 (PAT innovations) offers practical guidance for the implementation of Raman spectroscopic solutions in potentially explosive atmospheres. In view of the increasing spread of this technology and its specific safety-related challenges, the aim is to standardise and simplify it. The publication shows how companies can fulfil the regulatory requirements, particularly with regard to ATEX and laser protection, and what options are available if manufacturer conformities are not sufficient.
The new AK-Praxis of the NAMUR working group 3.6.3 (PAT innovations) offers practical guidance for the implementation of Raman spectroscopic solutions in potentially explosive atmospheres. In view of the increasing spread of this technology and its specific safety-related challenges, the aim is to standardise and simplify it. The free publication shows how companies can fulfil the regulatory requirements, particularly with regard to ATEX and laser protection, and what options are available if manufacturer conformity is not sufficient.
AK-Praxis was created due to more frequent Raman measurements
The new working group practice describes the approach of members of NAMUR working group 3.6.3 Process Analysis Technology (PAT Innovations) when implementing Raman spectroscopic solutions in hazardous areas. This topic is included because the number of Raman measurements has risen sharply in recent years and the effort involved in implementing them in hazardous areas may be more complex compared to the long-established NIR spectroscopy.
An increased effort in safety-related considerations always occurs when there is a need to deviate from the manufacturer's declarations of conformity. In the case of Raman spectroscopy, this may be necessary if the full potential of the technology is to be utilised by using high laser powers. This procedure requires an intensive coordination process with the company's internal colleagues in process and plant safety. Each case must be considered individually and compared with the local specifications and requirements.
Declarations of conformity as a central problem
The declarations of conformity, which are generally not formulated very comprehensively by the manufacturers of spectrometers and accessories, make such an analysis very time-consuming. In addition, the integration of third-party accessories usually increases the effort involved. The intended combination of several components with declarations of conformity requires a final inspection by a qualified person of the operator or an independent testing organisation.
Furthermore, an increasing range of process Raman systems can be observed, e.g. due to developments in MEMS technology, which makes the use of Raman devices more competitive, e.g. compared to NIR spectroscopy. At the same time, however, the process suitability of some devices is also increasing in terms of robustness and the possibility of use in potentially explosive atmospheres. It is therefore to be expected that the use of Raman spectroscopy in the chemical and pharmaceutical process industry will continue to increase.
Simplification and standardisation of Raman implementation
The aim of AK-Praxis is to simplify and standardise the implementation of Raman spectroscopic solutions in hazardous areas for users. The benefit for manufacturers of Raman spectrometers is that the needs of users are presented transparently. General and safety-related requirements are derived from the examples of Raman applications implemented by member companies and their implementation is described. A distinction is made between necessities (e.g. ATEX and laser protection) and user wishes.
In some cases, the specifications in the manufacturer's declarations of conformity may limit the possibilities of the measuring system to such an extent that the original analytical problem can no longer be solved. In this case, we refer to the possibility of assessing alternative installation concepts described in the Hazardous Substances Ordinance. The description contains both the technical and legal requirements as well as the references to standards and laws relating to occupational health and safety and the ATEX Directive for the EU and Germany. These requirements explicitly refer to the use of Raman spectrometers in potentially explosive atmospheres as PCT operating equipment. Requirements relating to functional safety through Raman spectroscopy are not dealt with here.
Further information can be found at www.namur.net.
