EEBD FEATURES SNM provides breathable air contained in a cylinder through a pneumatic system which adjusts quantity and pressure of air so to make all parametres suitable for breathing. The cylinder contains 600 litres, which under normal conditions of use are enough to grant about 15 minute duration. However, this value is indicative, because it can be significantly influenced by numerous parameters such as: the effort exerted during the escape, the user’s size and his own stress condition. The pressure reduction is fulfilled in the pneumatic circuit thanks to the presence of two elements called first stage, or pressure reducer, and second stage or demand valve. In SNM the first stage is built in the cylinder valve so that the first stage and the valve are one object only. This solution provides a lot of benefits as to simplicity and lightness. The device is activated by turning the valve knob. The handle has a loose ring that prevents accidental openings or closings. As required by the norm, there is a seal that shows whether the device is intact with its entire reserve of air. The pressure reducer is also equipped with a pressure gauge that provides information on the cylinder charge (the needle must be within the green field). The air coming from the cylinder through the valve meets the first stage, thereby reducing its pressure until the value of "medium pressure" and then reaches the second stage, where flow and pressure are reduced to such a point that air is finally ready to enter into the mask through the demand valve. The demand valve and the mask always remain within a slight positive pressure that prevents the entry of polluted air from outside. The
whole apparatus is supported and protected by an appropriate bag with a strap and belt with a pocket to house the mask with the demand valve (second stage) before use.
MAIN COMPONENTS The Pneumatic Circuit of SNM consists of the following elements:
Cylinder: This is a steel cylinder with a 3 lt. hydraulic capacity, working pressure of 200 bar. On request are also available versions with a 300 bar cylinder made of composite materials.
Cylinder valve-pressure reducer: the cylinder valve and pressure reducer (or first stage) are obtained by the same body made of hot printed nickel coated brass. Moreover, this group includes.
Gauge.:- Equipped with an external shockproof rubber protection, is housed on the body of the valve, to indicate the cylinder charge. It is directly connected to the high pressure outlet to provide this information also when valve is closed; it has a relief device which prevents over pressurization of the gauge housing in case of accidental breakage. In addition, in such a case, the gauge is fitted with a flow restriction which limits to 25 l/min (with an initial pressure of 200 bar) the air loss from the cylinder.
Safety valve:- It’s on the head of medium pressure chamber of the pressure reducer and is activated during malfunction of the same, to avoid that its components, sized to work at medium or low pressure, can be submitted to dangerous pressures. It is designed so to deliver and dispose at least 400 l/min and to avoid that the medium pressure exceeds 30 bar.
Threaded connection:- for cylinder charge. According to EN 144-1, it is fitted with a non-return valve that prevents air escape and allows the disconnection from the compressor after completing charging.
Medium pressure hoses:-Made of reinforced rubber. When working pressure is between 7,5 and 8 bar, they must resist for at
least 15 minutes at 30 bar.
Demand valve E400 AP/A SNM:- this device works at 7,5 bar and supplies air at a higher slightly pressure than the atmospheric one (positive-pressure) in a quantity equal to the one when breathing. The demand valve E400 is equipped with a connecting thread to the mask as suggested by EN 137 (AP/A).
Masks C607 SP/A and SFERA SP/A:- the SNM can be used either with C607 or SFERA positive-pressure mask, both available in EPDM and silicone. These masks, certified to EN 136, are of Class 3 and therefore suitable for burdensome uses.The SNM bag is designed to support the cylinder valve with the reducing pressure valve and is made of a self-extinguishing fabric with a shoulder belt and a waist belt, made of extinguishing tape. The bag contains the demand valve and the mask when the respirator is not worn.
SEKUR NAVY MASK is an isolating escape device equipped with full face mask and demand valve and is
Classified for 15 minutes duration.
REFERENCE NORM
EN 402:2004 – Lung governed demand self-contained open-circuit compressed air breathing apparatus with full
Face mask or mouthpiece assembly for escape.
CERTIFICATIONS
- CE Certified according to Form B of 96/98/EC MED
Directive
- CE Certified according to Article 10 of 89/686/EEC
Directive
- CE Certified according to 97/23/EC PED Directive
USE
- Escape device;
- Airline back-up device through SWOV automatic switch Over valve.