Abstract: A collective NBC filtration system (FIG. 1A) for providing positive-pressure purified air to a plurality of subjects in a protected space, or in an environment which cannot be maintained at positive pressure, in conjunction with one or more facepiece fluidly connected to the NBC filtration system. The system comprises: A casing body [102] including a first section [136] defining an inner volume therein, and a second section [138] adjacent to the first section. The second section includes an inlet port [116], The first section has a larger cross-section than the second section, and forms a peripheral first ledge [142] surrounding the second section. At least one NBC filter accommodated in the inner volume. The at least one NBC filter is supported on the first ledge [142], A lid [104] including a central portion [154] and a second ledge [152] surrounding the central portion. The central portion [154] includes a plurality of outlet ports [118], which are sealable.

Abstract: An NBC filtration system whose main components are a filter unit, a blower, a manual air exchange backup unit and a changeover valve. The filter unit is elongated horizontally positioned along a top portion of a wall of the protected space. Inlet and outlet ports of the filter unit are located close to each other near a first extremity of the filter unit. The blower is driven by the electric motor through a second speed increasing transmission enabling rotation of an impeller of the blower. The blower is positioned along the filter unit near a second extremity distal from the inlet and outlet ports; The changeover valve has a tubular housing extending along the filter unit near the first extremity, and an internal displaceable tubular valve member. Each of the components may be replaced with a component of different capacity without effecting the other components.

Abstract: An engine air filter for heavy dust conditions such as used in heavy military and off-road vehicles, including a scavenging system, and a method of operation thereof. The air filter includes: a housing, a precleaner, a permeable filter, and a scavenger system. The scavenger system disposes of particles collected at the precleaner and on the upstream surface of the permeable filter. The scavenger system includes: an air suction source and a three way valve. The three way valve is airflow coupled to the precleaner, to the permeable filter and to the air suction source. The three way valve enables scavenging of the precleaner and the permeable filter alternately. Optionally, the air filter may further includes a pulse jet back-flow flush system.

Abstract: According to the present invention there is provided a device and method for atmospheric water harvesting operative in an alternating sequence of an absorption phase and a desorption phase. The device comprises an air permeable adsorbent substrate being subject to an atmospheric airflow during the absorption phase and being subject to a circulated airflow during the desorption phase. The device further comprises a liquid heated heat radiation element embedded in the adsorbent substrate and a heated liquid heating media being circulated in the heat radiation element during the desorption phase. The device may further comprise air shutters, where the direction of the atmospheric airflow being substantially transversal to the direction of the circulated airflow. The air shutters are capable of blocking an entrance and an exit of the atmospheric airflow during the desorption phase.

Abstract: An air filter for heavy dust conditions has an efficient scavenging system. The air filter includes: a housing, a permeable filter, and a scavenger system. The scavenger system disposes of particles collected on the upstream surface of the permeable filter. The scavenger system includes: an air suction source, and a shutter. The shutter is positioned substantially along, typically below, the permeable filter, at a certain distance from a wall, typically the bottom wall, of the housing. The air suction source draws air from a collecting space located between the shutter and the wall of the housing. The shutter is being selectively operated to permit or restrict passage there-through. The air suction source efficiently operates to scavenge particles from the collecting space when the passage through the shutter is at least partially restricted.

Abstract: A louver type blast valve making use of an aerodynamically configured blade, independently activated by air flow to block a blast shock wave and a subsequent return suction wave. The blast valve (FIG. 6) including a frame and at least one aerodynamically configured blade, independently activated by air flow to block a blast shock and a potentially following return wave. The aerodynamically configured blade having an elongated shape, including at least a steep convex surface and a flat or shallow concave surface, forming a leading edge and a trailing edge at the intersection of the surfaces. The blade being hinged to the frame about a longitudinal axis passing between the steep convex surface and the flat or shallow concave surface.

Abstract: A floor-space saving NBC filtration system for collective protection shelters with NBC filter unit and means for changing the NBC filtration system state between a ventilation mode, effective during normal times or conventional hazard, and a NBC protection mode, effective during NBC hazard. The NBC filtration system is contained in a space out of a comfortable reach of the shelter occupants thus saving usable floor-space. The means for changing the NBC filtration system state is operated from a location within the comfortable reach of the shelter occupants. The NBC filter unit inlet and outlet are located at close proximity to each other, a pre-filter outlet is located in proximity to the NBC filter unit inlet and outlet with a changeover valve, serving as means for changing the NBC filtration system state, located there between. Resulting in simple operation and space saving by the changeover valve replacing prior art space consuming flexible pipes.

Abstract: An air filter for heavy dust conditions has an efficient scavenging system. The air filter includes: a housing, a permeable filter, and a scavenger system. The scavenger system disposes of particles collected on the upstream surface of the permeable filter. The scavenger system includes: an air suction source, and a shutter. The shutter is positioned substantially along, typically below, the permeable filter, at a certain distance from a wall, typically the bottom wall, of the housing. The air suction source draws air from a collecting space located between the shutter and the wall of the housing. The shutter is being selectively operated to permit or restrict passage there-through. The air suction source efficiently operates to scavenge particles from the collecting space when the passage through the shutter is at least partially restricted.

Abstract: An engine air filter for heavy dust conditions such as used in heavy military and off-road vehicles, including a scavenging system, and a method of operation thereof. The air filter includes: a housing, a precleaner, a permeable filter, and a scavenger system. The scavenger system disposes of particles collected at the precleaner and on the upstream surface of the permeable filter. The scavenger system includes: an air suction source and a three way valve. The three way valve is airflow coupled to the precleaner, to the permeable filter and to the air suction source. The three way valve enables scavenging of the precleaner and the permeable filter alternately. Optionally, the air filter may further includes a pulse jet back-flow flush system.

Abstract: A floor-space saving NBC filtration system for collective protection shelters with NBC filter unit and means for changing the NBC filtration system state between a ventilation mode, effective during normal times or conventional hazard, and a NBC protection mode, effective during NBC hazard. The NBC filtration system is contained in a space out of a comfortable reach of the shelter occupants thus saving usable floor-space. The means for changing the NBC filtration system state is operated from a location within the comfortable reach of the shelter occupants. The NBC filter unit inlet and outlet are located at close proximity to each other, a pre-filter outlet is located in proximity to the NBC filter unit inlet and outlet with a changeover valve, serving as means for changing the NBC filtration system state, located there between. Resulting in simple operation and space saving by the changeover valve replacing prior art space consuming flexible pipes.

Abstract: A louver type blast valve making use of an aerodynamically configured blade, independently activated by air flow to block a blast shock wave and a subsequent return suction wave. The blast valve (FIG. 6) including a frame and at least one aerodynamically configured blade, independently activated by air flow to block a blast shock and a potentially following return wave. The aerodynamically configured blade having an elongated shape, including at least a steep convex surface and a flat or shallow concave surface, forming a leading edge and a trailing edge at the intersection of the surfaces. The blade being hinged to the frame about a longitudinal axis passing between the steep convex surface and the flat or shallow concave surface.

Abstract: The invention provides a low-resistance gas adsorption filter provided with an activated carbon bed of bulk density less than 0.6 gram/cubic centimeter, the activated carbon bed being free of chromium 6+ salt, the filter being characterized by a gas holding capacity exceeding 300,000 milligram Dimethyl-methyl Phosphonate (DMMP)×minute/cubic meter and an airflow resistance such that the numerical value of air flow resistance in Pascal per millimeter of bed thickness does not exceed by more than 50% the numerical value of air velocity in centimeters per second.

Abstract: The invention provides a solid filter body for a filter unit, including a sintered composition of adsorbing materials containing activated carbon having a particle size in the range of from 4 to 100 mesh, and a binder in the form of thermoplastic powder having a particle size in the range of from 10 to 250 mesh, the ratio of binder to adsorbent being less than 25% by weight, and the composition being sintered at a temperature below 250° C. The invention further provides a fluid filter unit including a casing having inlet and outlet openings housing the solid filter body and a method for manufacturing the solid filter body.

Abstract: The invention provides a compact, portable system for protection against the penetration of contaminated air into a protected space. The system includes a gas filter and an air-intake unit. There is also a blower for sucking air through the filter into the protected space. An air exhaust unit is provided with an over-pressure valve. For actuating the blower, a member is provided. With the system as described, at least the filter, the blower and the means for actuating the blower can be removed, stored and reassembled by the user.