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Non-electrical equipment has been used for over 150 years in industries with potentially explosive atmospheres and great experience has been gained with regard to the application of protective measures to reduce the risk of ignition down to an acceptable safety level. The use of non-electrical equipment in explosive atmospheres required the development of specific requirements with regard to the concept of protection against the ignition of explosive atmospheres, which to clearly define protection measures and to include the experience gained and extended over the years. The practical studies, laboratory research and methods for assessing and testing the hazard of ignition by hot surfaces presented within the paper have as main purpose the improvement of ignition hazard assessment in different operating conditions.

Due to the continuous technical and economic development of the human society, a large number of chemical substances and compounds in the form of combustible dusts and powders are increasingly being used in the technological processes present in various industrial branches. These combustible powders, during their production, handling and storage operations, in combination with air, may lead to potentially explosive atmospheres. The presence of combustible powders and dusts, and possibly the appearance of potentially explosive atmospheres, has led to the need to adopt and enforce protective measures to ensure an acceptable level of protection in accordance with current rules, protective measures materialized mainly through use within locations endangered by the presence of potentially explosive atmospheres of properly protected technical equipment so as to reduce the possibility of ignition of the surrounding explosive atmosphere. Therefore, in order to be able to establish with certainty the requirements of the technical equipment that can be used in potentially explosive atmospheres generated by the fuel / air mixture, it is necessary to know the type of dust, as well as a series of parameters defining its sensitivity to ignition with different sources and the severity of the explosion it can generate, parameters known as explosive characteristics The paper highlights the explosive characteristics of combustible powders, the methods and equipment necessary to carry out experimental tests to determine these characteristics. [ABSTRACT FROM AUTHOR]

Area classification is a method of analysing and classifying the environment where explosive gas atmospheres may occur so as to facilitate the proper selection and installation of apparatus to be used safely in that environment, taking into account gas groups and temperature classes. Implementation of new tools to calculate dispersed volume of combustible gases account a upgrading research methods concerning the classification of hazardous areas. Efficient and quick execution calculation of the dispersed volume for gases or vapours which can form explosive mixtures in the process of determining the classification of hazardous areas, can be achieved by using a software application. Using software tools as alternatives to old methods of calculation, we'll save time and we'll reduce operating costs to calculate dispersed volume of combustible gases from various sources of release. In addition we could do various analyzes or studies regarding dispersed volume of gases for different types of plants. [ABSTRACT FROM AUTHOR]

The researches and experiments regarding the electrical parameters of electric detonators are especially important taking into consideration ensuring the safety of life and human health when conducting blasting works. Equipments in special construction for potentially explosive atmospheres should not generate energy sources that could initiate an explosion, and the blasting operations have to take place in reliable and sure conditions. This paperwork addresses performance improvement of the present testing system of the electric detonators having in view a safe initiation during the blasting works. [ABSTRACT FROM AUTHOR]

This paper analyses the electrocution hazard in three-phase electrical networks that operate with the neutral point isolated from ground. The following cases are analyzed: short low-voltage electrical networks, long low-voltage electrical networks and highvoltage networks. In high voltage electrical networks, touching a phase is always dangerous even if the insulation resistances are considered to be infinitely high. The analyzed cases show that in three-phase electrical networks with ground-isolated neutral point, the value of the current which passes through the human body depends on its electrical resistance as well as on the insulation resistances of the phases to earth. [ABSTRACT FROM AUTHOR]

The static electricity is one of the potential ignition sources for the explosive atmospheres. In order to ensure an appropriate level of safety against explosions in Ex endangered areas, it is of a major importance to take adequate protective measures for preventing electrostatic discharges from persons. Preventing formation/discharging of static charges from persons suppose an assembly of measures and means to ensure appropriate paths for charges leak out (dissipation) to earth. This can be achieved by using dissipative clothing, appropriate electrically conductive footwear, appropriate flooring or other means for charge discharging to earth. The requirements regarding PPE for use in explosive atmospheres are given in the European Directive PPE 89/686/EEC [Government Decision no. 115/2004 + Government Decision no.809/2005]. The Directive stipulates that PPE intended for use in explosive atmospheres must be so designed and manufactured that it cannot be the source of an electric, electrostatic or impact-induced arc or spark likely to cause an explosive mixture to ignite. The test methods of textiles in general and the textile fabrics in particular, for assessment of protective performances against static electricity have been in a continuous development, together with development of new materials, dissipative from an electrostatic point of view. Within INSEMEX, a modern test stand had been carried out and experimented, for determination of the half decay time of charges on textile materials or the screening factor, for the purpose of assessing the dissipative capacity of charges on textile materials used in manufacturing protective garment, according to the requirements defined at European level. [ABSTRACT FROM AUTHOR]

The potential explosive zones are those industrial areas where there is a risk to be produced a mixture of air with gas, vapors, mists or combustible dust which can be ignited by the different ignition sources, resulting explosions which can produce life losses. The metallic materials of the equipment case or their components, from industrial installation, can become ignition sources by mechanical sparks and/or hot surfaces. The authors had identified and analyzed the ignition capacity by mechanical sparks on the main metallic materials and had established original solutions to prevent ignition of the explosive atmospheres. [ABSTRACT FROM AUTHOR]

The new tools for assessment of non-electrical Ex equipments consist in the series of specific procedures for evaluating and connected testing procedures. The series of mentioned procedures are based on the harmonized European norms, adopted in Romania, which are included in SREN 13463 standard series and deal "Non electrical equipment for use in potentially explosive atmospheres". The assessment procedures are elaborated and implemented into Product Certification Body - INSEMEX OEC, notified at Bruxelles for ATEX Directive. Also, the testing procedures are elaborated and implemented into Laboratory for Testing in Explosive atmospheres - LIEx. [ABSTRACT FROM AUTHOR]

Introduction: The Charcot neuro-osteoarthropathy is a devastating complication of diabetes, with negative impact on both prognosis and quality of life. Moreover, the diagnostic is often missed or delayed. Case report: A 50 years old male patient with dyslipidemia, overweight and hypertension was referred to our Diabetes Department in the context of newly diagnosed diabetes (HbA1C=11.7%), four days after left hallux trans-metatarsal amputation and debridement of the dorsal collection, for wet gangrene of the left hallux, with dorsal extension. The diagnostic of diabetic neuro-osteoarthropathy of the left foot was delayed several months. A good glycemic control was achieved with insulin glargine and metformin. We look further to introducing modern antidiabetic drugs with not only proven cardiovascular benefit but also good impact on weight. The patient needs to be managed by a multidisciplinary team, which has to include a podiatrist and a vascular surgeon. Conclusions: This case suggest the importance of rising diabetes and diabetic peripheral polyneuropathy awareness in all medical fields. [ABSTRACT FROM AUTHOR]

INTRODUCTION AND OBJECTIVES: Operational fatigue syndrome is a nosological entity characterized by debilitating fatigue and a variety of associated physical ailments, constitutional and neuropsychological. This disease is not well known, although most experts believe has its own set of symptoms. There are no tests to confi rm the diagnosis of chronic fatigue syndrome. Because of this, many patients and their family and friends experience some diffi culty accepting the disease. Fatigue is not imaginary, has a real substrate. It's body reaction to a combination of physical and emotional factors. MATERIALS & METHODS: This paper provides a review of the most important aspects of the operational fatigue syndrome: diagnostic criteria, pathogenesis, physiological factors and treatment. RESULTS: It's described the case of an air mishap focused on the key role of fatigue as trigger of this event. It's also described the infl uence of fatigue in case of an aero-medical evacuation mission on a distance of 8000 km. CONCLUSION: Understanding the pathophysiological mechanism of the events listed in operational fatigue is important from the perspective of interdisciplinary diagnosis and identifi cation of effective treatment methods for the disease. Operational fatigue is a factor with major impact on aviation safety. Prescription of vigilance-modulating medication has been discussed and has up to now been voted against in the Romanian Air Force. Legal and ethical issues, and also the lack of a widely accepted policy prevent their use in actual scenarios. [ABSTRACT FROM AUTHOR]

Conveyor belts are used for a long period of time in the industry branches where potentially explosive atmospheres could occur. Dangerous phenomena which can be in direct connection with the use of conveyor belts are the ones regarding: - sparks influence over the coating layer and/or resistance internal structure of the stopped conveyor belt; - propagation of a flame along the length of a conveyor belt that was exposed to a energy source relative high like a fire or due to blockage of a conveyor belt as a result of the driving mechanism still operating, that generate a local heating of the conveyor belt in contact with the driving drum, rollers or any other heating source generated by friction. Determining the safety parameters characteristic of the conveyor belts by employing test methods allows assessment of the safety level as well as certification of their explosion protection quality when used in environments with explosion danger. [ABSTRACT FROM AUTHOR]

The new tools for assessment of non-electrical Ex equipments consist in the series of specific procedures for evaluating and connected testing procedures. The series of mentioned procedures are based on the harmonized European norms, adopted in Romania, which are included in SREN 13463 standard series and deal "Non electrical equipment for use in potentially explosive atmospheres". The assessment procedures are elaborated and implemented into Product Certification Body - INSEMEX OEC, notified at Bruxelles for ATEX Directive. Also, the testing procedures are elaborated and implemented into Laboratory for Testing in Explosive atmospheres - LIEx. The new tools for assessment of non-electrical equipment could be applied to mining equipment classified in group I, categories M1 and M2. Up to now, our institute for mining safety and explosion proof protection has developed facilities for the following types of protection: - Protection by flow-restricting enclosure (fr); - Protection by flame-proof enclosure (d); - Protection by constructional safety (c). [ABSTRACT FROM AUTHOR]