A dust suction device includes: a main body composed of a bottom plate and a footboard, wherein a dust suction part is formed in the bottom plate, and the footboard seals the dust suction part and has suction holes formed on the upper part thereof to allow the dust to be sucked to the dust suction part; a number of springs provided on the bottom inside the bottom plate matching the number of suction holes; balls which are provided on the upper part of the springs and which are in close contact with the suction holes of the footboard and open and close the suction holes; and a suction part which is connected to a side portion of the main body through a hose and sucks the dust through the suction holes toward the dust suction part when the suction holes are open.

Provided are a system of highly clean rooms capable of continuously maintaining high cleanliness of air of class 1 or above and supplying enough oxygen inside the room for several persons to live in and a wall adapted to the structure of such a system. The system of highly clean rooms 10 is provided with a living space 6 and a space 5 between the roof and the ceiling as subspaces of an enclosed space formed by a room 1a. One of the lateral walls of the room 1a is constituted of a wall 9 with an internal space 7, which is a hollow wall. The internal space 7 and the living space 6 are in contact via an inner wall 9a of the wall 9, and a gas exchange membrane 26 is stretched in the inner wall 9a. Furthermore, a gas flow path 24 is provided inside the inner space 7 and the gas flow path 24 allows airtight communication between an opening 23 provided on the lowest part of the internal wall 9a and a gas entry opening of a fan filter unit 21 provided on a ceiling wall 2a inside the space 5 between the roof and the ceiling.

Provided are a system of highly clean rooms capable of continuously maintaining high cleanliness of air of class 1 or above and supplying enough oxygen inside the room for several persons to live in and a wall adapted to the structure of such a system. The system of highly clean rooms 10 is provided with a living space 6 and a space 5 between the roof and the ceiling as subspaces of an enclosed space formed by a room 1a. One of the lateral walls of the room 1a is constituted of a wall 9 with an internal space 7, which is a hollow wall. The internal space 7 and the living space 6 are in contact via an inner wall 9a of the wall 9, and a gas exchange membrane 26 is stretched in the inner wall 9a. Furthermore, a gas flow path 24 is provided inside the inner space 7 and the gas flow path 24 allows airtight communication between an opening 23 provided on the lowest part of the internal wall 9a and a gas entry opening of a fan filter unit 21 provided on a ceiling wall 2a inside the space 5 between the roof and the ceiling.

A ventilation apparatus according to the present invention comprises: a case having a flow hole; a flow guide positioned inside the case, the flow guide having an inflow opening that communicates with the flow hole, and the flow guide having a guide surface that slopes downward as the same extends outward; a swirler positioned in an area formed by the flow guide and configured to rotate in order to discharge a part of air introduced through the flow hole out of the case again, the swirler having a plurality of blades; a driving motor for rotating the swirler; and a grill member that covers the swirler outside the case and provides an air channel. The grill member comprises a grill rib that forms a suction channel for suctioning air and a discharge channel for discharging air. The discharge channel may be positioned outside the suction channel.

A ventilation apparatus according to the present invention comprises: a case having a flow hole; a flow guide positioned inside the case, the flow guide having an inflow opening that communicates with the flow hole, and the flow guide having a guide surface that slopes downward as the same extends outward; a swirler positioned in an area formed by the flow guide and configured to rotate in order to discharge a part of air introduced through the flow hole out of the case again, the swirler having a plurality of blades; a driving motor for rotating the swirler; and a grill member that covers the swirler outside the case and provides an air channel. The grill member comprises a grill rib that forms a suction channel for suctioning air and a discharge channel for discharging air. The discharge channel may be positioned outside the suction channel.

Positive air pressure is applied on a ventral side of a plant canopy and negative air pressure is applied on a dorsal side of the plant canopy. By this arrangement, the negative air pressure draws air supplied by the positive air pressure on the ventral side of the plant canopy across the plant canopy past the dorsal side of the plant canopy to withdraw heat from the plant canopy, for example, from an agricultural lighting system and/or humidity from plant respiration in a controlled indoor environment.

Positive air pressure is applied on a ventral side of a plant canopy and negative air pressure is applied on a dorsal side of the plant canopy. By this arrangement, the negative air pressure draws air supplied by the positive air pressure on the ventral side of the plant canopy across the plant canopy past the dorsal side of the plant canopy to withdraw heat from the plant canopy, for example, from an agricultural lighting system and/or humidity from plant respiration in a controlled indoor environment.

A fresh air cooling and ventilating system can include a whole house fan for introducing fresh air into a building structure. The fresh air cooling and ventilating system can include a whole house fan and/or a controller. The controller can be operably in communication with an air conditioning system and coordinate the usage of the fresh air cooling and ventilating system and the air conditioning system to reduce overall energy consumption. The system can be automated to run with no or minimal user input.

A pressure equalization device for installation on or at an entry of an attic of a home or other building is described. The pressure equalization device can be an access panel of an attic access hatch. The access panel is a solid, generally flat panel of material such as wood or plastic. The access panel includes an aperture that passes therethrough. The aperture is covered with an air-permeable cover made from a material such as cloth or plastic mesh. The mesh is constructed to allow air to pass through the aperture between the attic and interior of the building for purposes of equalizing pressure between them. Pores of the mesh are sized so that insects, rodents, and other animals and dust and debris cannot pass through and into the interior of the building.

A pressure equalization device for installation on or at an entry of an attic of a home or other building is described. The pressure equalization device can be an access panel of an attic access hatch. The access panel is a solid, generally flat panel of material such as wood or plastic. The access panel includes an aperture that passes therethrough. The aperture is covered with an air-permeable cover made from a material such as cloth or plastic mesh. The mesh is constructed to allow air to pass through the aperture between the attic and interior of the building for purposes of equalizing pressure between them. Pores of the mesh are sized so that insects, rodents, and other animals and dust and debris cannot pass through and into the interior of the building.