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In the present paper, the use of programmable microprocessors to develop a computerized stand for the preparation of a mixture of flammable/toxic/explosive gases in order to obtain mixtures at concentrations in explosive range is presented. The operating principle of the stand is based on the mixing of two volumetric flows, controlled with the help of microprocessors, where gases are stored and circulated at atmospheric pressure through cylindrical injectors, driven by stepper motors so that the gas circuit does not require valves. The exit of the stand is a homogenization chamber, with agitator and sensor to confirm the desired concentration of the mixture. This automated stand eliminates mechanical, electric or pneumatic valves from the gas circuits, avoiding elements with high mechanical resistance suitable for high pressures/depressions, removing the possibility of the return of the gas flow, without sensitivity to sudden pressures variations.

On the evening of 5 April 2014, at a building located on 122 Tomis Boulevard, Constanta Municipality, Constanta County, Romania, a restaurant with its kitchen on the ground floor and a lounge bar located on the first floor experienced a fire, one that resulted in four victims and total building destruction. An important step in the technical-scientific expertise was the investigation of the incident based on the elaboration of two fire scenarios using the Fire Dynamic Simulator (FDS) model, which observed the fire propagation, the generation of toxic gases (carbon monoxide that disoriented and intoxicated the victims, three of whom could not save themselves) depending on the location of the plausible ignition sources, and explained the destructive effects. This paper focuses on the steps required to identify the critical conditions that led to the occurrence of the unwanted event. Based on the calculations, hypothesis, and FDS simulations, the mechanism of the event occurrence was considered to be strongly related to the onsite observations and criminal file issued by the state authorities.

Thermal stability of explosives for civil use is a key security parameter. When the explosive is exposed to high tempera-tures in a given period of time can lead to undesirable phenomena such as decomposing or even very dangerous as un-controlled detonation.

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.

The article presents the innovative methods for belts employed in the belt conveyors operating in environment with potentially explosive atmosphere fulfilling the requirements given in the Directive 94/9/EC of the European Parliament. It is given that protection concepts are created with keeping equipment, that can ensure protection by preventing intrinsic ignition risks, in mind. The test method for determining the conveyor belt tendency to generate heat, flames or to glow when kept in stationary position is also mentioned.

The article describes test methods for determining the tendency of conveyor belts which operate in explosive atmospheres to generate heat or flames. It gives an overview of health and safety requirements stipulated in the ATEX Directive in Europe. It provides information on the assessment of ignition risk at conveyor belts. It cites several factors to consider when doing the test including steel drum, belt tensioning system and air flow system. It also illustrates the test stand for finding out the electrostatic field produced by operational conveyor belts.