Atex ref guide

Basic Concept for Explotion Protection, 2020

This brochure was put together carefully in conformance to the current status of standards and regulations. The respective amended version of the technical and statutory rules is binding. Errors and misprints do not justify any claim for damages. All rights reserved, in particular the rights of duplication, distribution and translation.

MATEC Web of Conferences

The flameproof enclosure type of protection is still one of the safest because it is based on a very simple and, therefore, unlikely fallible technology. If an explosive atmosphere penetrates an enclosure producing a trigger, the explosion occurs, but it remains confined within the enclosure. Engineers settled the concept that, for IIC areas, have to be necessarily used equipment with cylindrical flame paths, which usually feature a round-shape body that make more complicated the construction of panel boards. EN 60079-1 standard, states that flanged flame paths are allowed in the presence of hydrogen, therefore, in recent years, started the production of “Ex d” explosion-proof enclosures which are usable, as well as with gases of Group IIB, even in the presence of hydrogen. This means that the equipment can be used in an environment containing explosive atmosphere with hydrogen. Acetylene is, therefore excluded, but it has to be considered that the environments with the presence of ...

MATEC Web of Conferences

Based on the experience accumulated over time on the evaluation of equipment and installations in environments with potentially explosive atmospheres, this paper is intended to be an element of synthesis on issues related to the “in situ” assessment and solutions of solvency the deficiencies found. The assessment of these installations is very important in order to verify the implementation of measures that lead to minimizing the risk of ignition of explosive atmospheres. Evaluation of these installations is made through an on-site visit and on the basis of the technical documentation developed by the care of the user. In first part of the paper were presented the legal aspects regarding the placing on the market and the use of equipment designed for potentially explosive atmospheres. The paper is continuing with the presenting the technical aspects regarding the evaluation of equipment and installations operating in potentially explosive atmospheres followed by requirements for ele...

2021

Offshore oil and gas operations carry a high risk of explosions, which can be efficiently prevented in many cases. The two most used approaches for prevention are: (1) the “International Electrotechnical Commission System for Certification to Standards Relating to Equipment for Use in Explosive Atmospheres” (IECEx) and (2) European “Atmosphere Explosible” (ATEX) schemes. The main shortcoming for the IECEx scheme is in the fact that it does not cover nonelectrical equipment, while for the ATEX scheme, it is due to the allowed self-certification for a certain category of equipment in areas with a low probability of explosions, as well as the fact that it explicitly excludes mobile offshore drilling units from its scope. An advantage of the IECEx scheme is that it is prescribed by the US Coast Guard for protection against explosions on foreign mobile offshore drilling units, which intend to work on the US continental shelf but have never operated there before, with an additional requir...

Bezpieczeństwo i Technika Pożarnicza Safety & Fire Technique, 2018

Aim: In the engineering practice, explosion protection is provided through the following steps: the elimination of the flammable material, the explosive atmosphere and the source of ignition. Another step is to limit the impact of the potential explosion. Electrical equipment might constitute the source of ignition for mixtures of flammable substances with air. The aim of the article is to present a new type of electrical equipment protection. According to the current technical standards, Ex p equipment is defined either as an enclosure with a constant static overpressure inside or purged enclosures with the use of clean air not containing flammable substances that could generate a hazardous atmosphere. This type of protection usually requires regular maintenance, complicated venting and/or frequent control of correct operation. Project and methods: Electrical equipment designed to work in hazardous areas is designed with various types of protection ensuring safety in the case of a hazardous atmosphere created near the device. In order to present the concept of the new protection type, current technical standards were analysed to gather technical prerequisites. The Solid Edge environment was used to create 3D models of control and indicating equipment (CIE). The diagram presenting the concept of the whole device was also created. The aim of the project was to present the concept of the new mixed-type pressurised equipment. Results: The design of the device proves that it is possible to create a new type of explosion protection of electrical equipment which has not been described in current technical standards. The concept assumes the use of stationary compressed nitrogen installations present in many factories. The installation will maintain a constant positive pressure inside the enclosure. It is also feasible to use portable inert gas tanks, which will require additional means of protection. The proposed design was checked against the set requirements. For the designed equipment, ready formulae were used to determine screw tightening torques in order to activate the device after exceeding specific parameters, such as the gas flow rate. Conclusions: The current technical standards give space for designing a new type of electrical equipment protection. The article describes the outcomes of the research and project work conducted to visualise the concept. These types of equipment protection can be certified for all working conditions, which increases their applicability potential.