01. Purpose of negative pressure isolation ward
The negative pressure isolation ward is one of the infectious disease areas in hospital, including negative pressure isolation wards and related auxiliary rooms. Negative pressure isolation wards are wards used in hospital to treat patients with direct or indirect airborne diseases or to investigate patients suspected of airborne diseases. The ward should maintain a certain negative pressure to the adjacent environment or room connected to it.
02. Composition of negative pressure isolation ward
The negative pressure isolation ward consists of an air supply system, an exhaust system, a buffer room, a pass box and a maintenance structure. They jointly maintain the negative pressure of the isolation ward relative to the outside world and ensure that infectious diseases will not spread outward through the air. The formation of negative pressure: exhaust air volume > (air supply volume + air leakage volume); each set of negative pressure ICU is equipped with supply and exhaust system, usually with fresh air and full exhaust systems, and the negative pressure is formed by adjusting the air supply and exhaust volumes. Pressure, supply and exhaust air are purified to ensure that the air flow does not spread pollution.
03. Air filter mode for negative pressure isolation ward
The supply air and exhaust air used in negative pressure isolation ward are filtered by air filters. Take the Vulcan Mountain isolation ward as an example: the ward cleanlinesss level is class 100000, the air supply unit is equipped with a G4+F8 filter device, and the indoor air supply port uses a built-in H13 hepa air supply. The exhaust air unit is equipped with G4+F8+H13 filter device. Pathogenic microorganisms rarely exist alone (whether it is SARS or the new coronavirus). Even if they exist, their survival time is very short, and most of them are attached to aerosols with particle diameters between 0.3-1μm. The set three-stage air filter filtration mode is an effective combination for removing pathogenic microorganisms: the G4 primary filter is responsible for the first-level interception, mainly filtering large particles above 5μm, with a filtration efficiency >90%; the F8 medium bag filter is responsible for the second level of filtration, mainly targeting particles above 1μm, with a filtration efficiency >90%; the H13 hepa filter is a terminal filter, mainly filtering particles above 0.3 μm, with a filtration efficiency >99.97%. As a terminal filter, it determines the cleanliness of the air supply and the cleanliness of the clean area.
H13 hepa filter features:
• Excellent material selection, high efficiency, low resistance, water-resistant and bacteriostatic;
• The origami paper is straight and the fold distance is even;
• Hepa filters are tested one by one before leavinthe factory, and only those that pass the test are allowed to leave the factory;
• Clean environment production to reduce source pollution.
04. Other air clean equipment in negative pressure isolation wards
A buffer room should be set up between normal working area and auxiliary prevention and control area in negative pressure isolation ward, and between auxiliary prevention and control area and prevention and control area, and the pressure difference should be maintained to avoid direct air convection and contamination of other areas. As a transition room, the buffer room also needs to be supplied with clean air, and hepa filters should be used for the air supply.
Features of hepa box:
• The box material includes spray-coated steel plate and S304 stainless steel plate;
• All joints of the box are fully welded to ensure long-term sealing of the box;
• There are various sealing forms for customers to choose from, such as dry sealing, wet sealing, dry and wet double sealing and negative pressure.
There should be pass box on the walls of isolation wards and buffer rooms. The pass box should be a sterilizable two-door interlocking delivery window for delivering items. The key is that the two doors are interlocked. When one door is opened, the other door cannot be opened at the same time to ensure that there is no direct air flow inside and outside the isolation ward.
Post time: Sep-21-2023