General guidelines for biosafety in microbiology and biomedical laboratories - summary of classification, grading and scope of application of laboratories

General guidelines for biosafety in microbiology and biomedical laboratories - summary of classification, grading and scope of application of laboratories
5 Classification, grading and scope of the laboratory
5.1 Classification
5.1.1 General Biosafety Protection Laboratory (without using experimental vertebrates and insects).
5.1.2 Experimental vertebrate biosafety protection laboratory.
5.2 Classification Each type of biosafety protection laboratory is divided into four levels according to the degree of damage of the microorganisms and their toxins treated. The biosafety protection requirements of the laboratories at all levels are: lowest in the first level and highest in the fourth level.
5.3 Scope of application
5.3.1 General Biosafety Protection Laboratory
5.3.1.1 First-level biosafety laboratory laboratory structure and facilities, safe operating procedures, safety equipment for microorganisms known to have no pathogenic effects on healthy adults, such as general microbiology laboratories for teaching Wait.
5.3.1.2 Secondary Biosafety Laboratories Laboratory structures and facilities, safe operating procedures, and safety equipment are applicable to microorganisms that have a medium potential hazard to humans or the environment.
5.3.1.3 The three-level biosafety laboratory laboratory structure and facilities, safe operating procedures, and safety equipment are applicable to pathogenic microorganisms and their toxins that cause serious or even lethal diseases mainly through respiratory routes. There are usually vaccines to prevent infection.
HIV research (with the exception of serological tests) should be conducted in a tertiary biosafety laboratory.
5.3.1.4 The four-level biosafety protection laboratory laboratory structure and facilities, safety operation procedures and safety equipment are suitable for human beings with high risk. The route of transmission or transmission through the aerosol route is unknown. Pathogenic microorganisms and their toxins for vaccines or treatments. Unidentified microorganisms similar to the above are also required to be carried out in a four-level biosafety laboratory. After sufficient data, it is decided whether such microorganisms or toxins should be treated in a four-stage or lower-level laboratory.
5.3.2 Experimental vertebrate biosafety protection laboratory, the applicable microbial scope is the same as the general biosafety protection laboratory of the same level.
6 Basic requirements for general biosafety protection laboratories
6.1 Level 1 Biosafety Protection Laboratory
6.1.1 Safety equipment and personal protection
6.1.1.1 It is generally not necessary to use special safety equipment such as biological safety cabinets.
6.1.1.2 Staff should wear overalls and protective glasses during the experiment.
6.1.1.3 Workers should wear gloves when there is skin damage or rash on hand.
6.1.2 Special requirements for laboratory design and construction
6.1.2.1 There should be a sink in each laboratory, which should be placed close to the exit.
6.1.2.2 The inner surface of the laboratory envelope shall be easy to clean. The floor should be non-slip, no gaps, and no carpets should be laid.
6.1.2.3 The surface of the test bench should be impervious to water, corrosion and heat.
6.1.2.4 Furniture in the laboratory should be secure. For easy cleaning, a certain gap should be maintained between the various furniture and equipment. There should be a table (rack) dedicated to the placement of biological waste containers.
6.1.2.5 If the laboratory has windows that can be opened, screens should be provided.
6.2 Secondary Biosafety Protection Laboratory
6.2.1 Safety equipment and personal protection
6.2.1.1 Oxygen aerosols or spillages that may cause pathogenic microorganisms should be performed in biosafety cabinets (Class II biosafety cabinets) or other physical containment equipment, and personal protective equipment should be used.
6.2.1.2 The treatment of high-concentration or large-capacity infectious materials must be carried out in biological safety cabinets (Class II biological safety cabinets) or other physical suppression equipment, and use personal protective equipment.
Centrifugation of the above materials can be performed in the laboratory if a sealed centrifuge rotor or safety centrifuge cup is used and they only open and close the infectious material in the biosafety cabinet.
6.2.1.3 When microbiological operations are not possible in the biosafety cabinet and external operations must be taken, face protection devices (goggles, masks, individuals) must be used to prevent spillage or nebulization of infectious materials. Respiratory protection or other spill-proof protective equipment).
6.2.1.4 Protective clothing such as overalls or blouses should be worn in the laboratory. Protective clothing must be removed and left in the laboratory when leaving the laboratory. Do not wear out, or carry it home. Used work clothes should be disinfected in the laboratory and then washed or discarded.
6.2.1.5 Gloves should be worn when hands may come into contact with infected materials, contaminated surfaces or equipment. If spillage or spillage of infectious materials may occur, two pairs of gloves should be worn. Do not leave the lab with gloves. The gloves can be removed after the work is completely finished. Disposable gloves must not be cleaned and reused.
6.2.2 Special requirements for laboratory design and construction
6.2.2.1 Biosafety protection The secondary laboratory must meet the requirements of paragraphs 6.1.2 of this standard.
6.2.2.2 Facilities that implement various disinfection methods, such as autoclaves and chemical disinfection devices, should be disposed of.
6.2.2.3 Eyewash devices should be provided.
6.2.2.4 The laboratory door should be locked and automatically closed.
6.2.2.5 The laboratory outlet shall have a luminous indicator.
6.2.2.6 The laboratory should have a ventilation number of not less than 3 to 4 times per hour.
6.3 Level 3 Biosafety Protection Laboratory
6.3.1 Safety equipment and personal protection
6.3.1.1 Biosafety cabinets of Class II or above must be installed in the laboratory.
6.3.1.2 All operations involving infectious materials should be carried out in a biosafety cabinet. When such operations have to be carried out outside the biosafety cabinet, it is necessary to use individual protection and comprehensive protection measures using physical suppression equipment.
6.3.1.3 Personal protective equipment must be used in the operation of infectious tissue culture and the possibility of producing infectious aerosols.
6.3.1.4 Respiratory protection devices should be used when aerosols cannot be safely and effectively confined to a certain extent.
6.3.1.5 Staff members should wear back-open work clothes or other protective clothing in a dedicated locker room (or buffer room) before entering the laboratory work area. Work clothes must be taken off the work clothes, and work clothes should not be taken out of the laboratory. Work clothes that can be reused must be sterilized and cleaned.
6.3.1.6 Gloves must be worn during work (two pairs are appropriate). Disposable gloves must be disinfected and discarded.
6.3.1.7 An effective disinfectant, eye cleanser or saline must be provided in the laboratory and is readily accessible. Can be equipped with emergency medicine.
6.3.2 Special requirements for laboratory design and construction
6.3.2.1 Site selection The three-level biosafety protection laboratory may be located in a building with other uses, but must be self-contained. The area is separated from the public corridor or public part by an isolation gate.
6.3.2.2 Planar layout a) The core area of ​​the Level 3 Biosafety Protection Laboratory consists of an experimental room and a buffer room connected to it.
b) The buffer chamber forms a passage into the experimental room. Two interlocking doors must be provided. When one of the doors is open, the other door is automatically closed. If an electric interlock is used, both doors must be open when the power is off. A second change can be made in the buffer room.
c) When the laboratory ventilation system does not have an automatic control device, the buffer room area should not be too large, and should not exceed one-eighth of the experimental room area.
d) Class II or Class III biosafety cabinets should be installed away from the experimental population, avoiding areas where workers frequently move around, and facilitating the formation of airflow patterns from the “clean” area to the “contaminated” area.
6.3.2.3 Enclosure structure a) The inner surface of the enclosure (including the buffer room) must be smooth, corrosion-resistant and waterproof to facilitate disinfection and cleaning. All gaps must be reliably sealed.
b) All doors in the laboratory can be automatically closed.
c) No windows shall be provided except for the observation window. The observation window must be a sealed structure, and the glass used is not broken glass.
d) The ground should be free of leakage, smooth but not slippery. Do not use grounded floors such as floor tiles and terrazzo.
e) The angle between the ceiling, the floor and the wall is round and reliable, and insects and rats should be prevented from drilling into the wall.
6.3.2.4 Ventilation and air conditioning a) A separate ventilation and air conditioning system must be installed to control the direction of the laboratory airflow and pressure gradient. The system must ensure that the indoor air is not discharged from other parts of the laboratory or to the outside of the laboratory, except that it is efficiently filtered out through the exhaust duct. It also ensures that the airflow in the laboratory flows from the “clean” area to the “contamination”. "area. The layout of the air inlet and exhaust vents should minimize the dead space in the experimental area.
b) The ventilation and air conditioning system is a direct exhaust system, and part of the return air system shall not be used.
c) Environmental parameters: The internal pressure of the laboratory is maintained relative to the outside of the laboratory. The relative pressure between the experiments is preferably -30Pa~-40Pa, and the relative pressure between buffers is -15Pa~-20Pa. The temperature and humidity in the laboratory are suitable for controlling the comfort of the human body, or according to the process requirements. The air cleanliness in the laboratory is preferably in the order of seven to eight as defined in GB 50073-2001 <<Design Code for Clean Plants. Laboratory artificial lighting should be uniform, not dazzling, and the illumination should be no less than 500lx.
d) In order to ensure that the airflow in the laboratory flows from the “clean” area to the “contaminated” area, the layout of the exhaust vents on both sides should not be used in the laboratory. Ventilation design for the upper row should not be used. The internally efficiently filtered air discharged from the biosafety cabinet can be directly vented to the atmosphere through the system's exhaust ducts, or it can be sent to the building's exhaust system. The pressure balance between the biosafety cabinet and the exhaust system should be ensured.
e) The inlet air of the laboratory should be filtered by primary, middle and high efficiency.
f) The exhaust of the laboratory must be directly discharged into the air at a speed of not less than 12 m/s after high efficiency filtration or other methods. The exhaust vent should be away from the system air inlet. The treated exhaust can also be discharged into the building's exhaust ducts, but must not be returned to any part of the building.
g) Air inlet and exhaust air Efficient filters must be installed in the tuyere of the laboratory on the enclosure to avoid contamination of the duct.
h) In the laboratory ventilation system, a gas-tight regulator valve shall be installed at the inlet and exhaust manifolds, and if necessary, it may be completely closed for indoor chemical fumigation.
i) All components used in the laboratory's ventilation system must be airtight. The high efficiency filter used must not be a wooden frame.
j) The fan should be installed to start the automatic interlock device to ensure that the fan is turned on after the fan is started. When shutting down, turn off the blower and then turn off the blower.
k) Do not install a split air conditioner in the laboratory.
6.3.2.5 Safety devices and special equipment a) Class II or III biological safety cabinets must be installed in the main laboratory. The installation location should meet the requirements in 6.3.2.5d).
b) Continuous flow centrifuges or other equipment that may generate aerosols should be placed in physical containment equipment that is capable of filtering the aerosols it may produce through a high efficiency filter. Exhaust air from all other exhaust devices (fume hoods, exhaust hoods, etc.) that must be installed in the laboratory must be filtered through a high efficiency filter before being discharged. The interior arrangement should facilitate the formation of a flow pattern of airflow from the "clean" zone to the "contaminated" zone.
c) An autoclave or other disinfection device that does not produce steam must be installed in the laboratory.
d) A transfer window should be provided between the experiment and the outside. The double doors of the transfer window shall not be opened at the same time, and a physical disinfection device shall be provided in the transfer window. Infectious materials must be placed in a closed container to pass through the transfer window.
e) A pressure display alarm device must be placed at a prominent location in the laboratory population to show the negative pressure condition between the laboratory and the buffer room. When the negative pressure indication deviates from the preset interval, it must be able to alert the personnel inside and outside the laboratory by means of sound and light. The display of the airflow resistance of the delivery and exhaust high efficiency filter can be increased on the device.
f) There is no power outage during the start-up of the laboratory. A dual power supply should be used. If it is difficult to achieve, you should install a backup power supply or an uninterruptible power supply that can be automatically switched during a power outage to supply power to key equipment (biological safety cabinets, fume hoods, exhaust hoods, and lighting).
g) A sink can be installed in the buffer room. The water supply door of the sink must be pedal, elbow or automatic switch. If the sink is located in the main laboratory, the sewer must be separated from the building's sewer line and clearly marked. The sewage must be disinfected. The sink is for hand washing only and must not be poured into any infectious material. The water supply pipe must be equipped with a backflow prevention device. Do not install floor drains in the laboratory.
6.3.2.6 Others a) The surface of the test bench shall be impervious to water, corrosion and heat.
b) The furniture in the experimental air should be firm. For easy cleaning, a certain gap should be maintained between the various furniture and equipment. There should be a table (rack) dedicated to the placement of biological waste containers. The corners and protruding parts of furniture and equipment should be smooth and burr-free, and should be rounded.
c) The required vacuum pump should be placed in the laboratory. The vacuum line must be equipped with an online high efficiency filter.
d) Cylinders such as compressed air should be placed outside the laboratory. The pipe passing through the envelope must be sealed with a non-shrinking sealing material between the pipe and the envelope. The gas line must be equipped with an on-line high efficiency filter and backflow prevention device.
e) Eyewash devices should be installed in the laboratory.
f) Laboratory outlets should have illuminated signs.
g) A communication system must be set up inside and outside the laboratory.
h) Information such as laboratory records in the laboratory should be sent to the laboratory via a fax machine.
6.4 Level 4 Biosafety Protection Laboratory'
The four-level biosafety protection laboratory is divided into a safety cabinet type laboratory and a positive pressure service type laboratory. In a safe cabinet laboratory, all microbial operations are performed in a Class III biosafety cabinet. In a positive pressure suit laboratory, workers must wear special positive pressure clothing to protect the garment.
6.4.1 Safety equipment and personal protection
6.4.1.1 The operation of all infectious materials in the laboratory must be carried out in a Class III biosafety cabinet. If the staff wears a holistic positive pressure overalls supplied by a life support system, the relevant operations can be performed in a Class II biosafety cabinet.
6.4.1.2 All staff members must be replaced with a full set of laboratory clothing, including underwear, underwear, shirts or jumpsuits, shoes and gloves. All of these laboratory protective suits must be removed from the locker room before showering and leaving the lab.
6.4.2 Special requirements for the design and construction of safety cabinets
6.4.2.1 Site selection. The laboratory should be built in a separate building or in a separate area within the laboratory building.
6.4.2.2 Plane layout a) The core area of ​​the laboratory consists of a room (safety cabinet room) with a Class II biosafety cabinet and an access channel. There are at least three sections in the access passage, followed by the outer dressing room, the shower room and the inner dressing room. There is an automatic interlock between any adjacent doors to prevent two adjacent doors from being opened at the same time. For materials, articles and equipment that cannot be carried into and out of the safety cabinet from the locker room, an autoclave with a double door structure shall be provided on the wall of the safety cabinet room, and there shall be a immersion disinfection tank, a fumigation chamber or ventilation with a disinfection device. Transfer windows for transfer or disinfection. An emergency exit channel with an airlock chamber must be provided.
b) A buffer zone can be set around the safety cabinet room, which is a circular corridor or a buffer room, which is part of the core area. Buffer construction requires the same level of biosafety protection laboratory.
6.4.2.3 Enclosure structure a) The inner wall of the cabinet and floor of the safety cabinet room and the interior dressing room shall form a sealed inner casing. The floor should be sealed as a whole and the corners of the wall should be rounded. The inner surface of the room should be waterproof and corrosion resistant. All gaps in the structure should be sealed. Minimize the gap around the safety cabinet compartment and the interior locker door and seal it for disinfection. All downpipes on the floor of the cabinet floor lead directly to the liquid disinfection system, and the sewers and other service lines are fitted with high-efficiency filters to prevent pests from entering.
b) The door entering the laboratory can be automatically closed and can be locked. All equipment that transfers items inside and outside the laboratory must be double-opened and there must be an automatic interlock between the two doors.
c) Any window is required to be broken and sealed.
d) Install a double-door autoclave for disinfecting the items delivered from the positive biosafety cabinet and the safety cabinet chamber on the laboratory wall. Its outer door opens outside the laboratory. The gap must be well sealed.
6.4.2.4 Ventilation and air conditioning a) A well-designed in-line ventilation system must be installed. The system's intake and exhaust designs should ensure that the directed airflow flows from the smallest hazardous area to the largest potentially hazardous area. The layout of the air inlet and exhaust vents should minimize the dead space in the experimental area.
b) The pressure difference and airflow direction of adjacent areas must be monitored and an alarm is installed. A pressure gauge panel is installed at the entrance of the outer dressing room to display and monitor the pressure or differential pressure of each zone in the laboratory and the air volume of the incoming and exhaust air.
c) The automatic control and alarm devices for the ventilation system must be designed to ensure that there is no positive pressure in the laboratory and that the pressure and differential pressure in each room are normal. The exhaust of the Class II biosafety cabinet must be connected directly to the exhaust duct. The exhaust duct must be set separately and must not be connected to the building exhaust system.
d) Environmental parameters: The safety cabinet chamber must maintain the highest degree of negative pressure, and its relative pressure should not be higher than -60 Pa; the relative pressures of the safety cabinet chamber, the inner locker room, the shower room and the outer dressing room are sequentially increased, between adjacent rooms. There should be a pressure difference between 10Pa and 15Pa. The air cleanliness in the core area is preferably from seven to eight. Laboratory artificial lighting should be uniform, not dazzling, and the illumination should be no less than 500 1x.
e) The intake air is a three-stage filtration system, and the final stage must be filtered by a high efficiency filter. ,
f) Exhaust from the entire core area must be processed continuously through two high efficiency filters. The exhaust vents should be kept away from the laboratory area and the air inlet.
g) Air inlet and exhaust air Efficient filters must be installed in the air outlets of the laboratory in the enclosure to avoid contamination of the ducts. High-efficiency filter tuyere construction must be disinfected in situ prior to replacement of the HEPA filter. Or use a filter structure that can be replaced in an airtight bag, and then sterilize or incinerate the high efficiency filter. Each HEPA filter must be tested before and after installation and must be tested once a year after operation.
6.4.2.5 Safety devices and special equipment a) The safety cabinet room must be provided with a positive biological safety cabinet.
b) The door of the autoclave must be automatically controlled, and the outer door can be opened only after the sterilization cycle is completed.
c) A double-door liquid soaking tank, a fumigation chamber or a ventilated air lock chamber for disinfection must be provided to sterilize non-autoclaved items from the Class III biosafety cabinet and the safety cabinet chamber for safe access.
d) If there is a central vacuum line system, it should not be used outside the safety cabinet room. The on-line high efficiency filter is as close as possible to each point of use or gate. Filters should be easy to disinfect or replace on site. Other gas and liquid lines leading to the safety cabinet require the installation of protective devices to prevent backflow.
e) From the inner locker room (including the bathroom), the safe cabinet room sink, the floor drain and the liquid from the autoclave and other sources must be disinfected before being discharged to the sewer, preferably by heat sterilization. The floor drain must have a water seal filled with a chemical disinfectant that is effective against the infectious material being tested, which leads directly to the liquid disinfection system. Efficient filters should be installed at the sewer and other service lines. The liquid discharged from the shower room and the outer dressing room and the toilet can be discharged directly into the sewer without any treatment. The disinfection effect on liquid waste must be confirmed.
f) Emergency power supplies that can be automatically activated must be provided for the ventilation system, alarms, lighting, access control and biosafety cabinets in the core areas of the laboratory (safety cabinet, interior locker, shower and exterior changing rooms).
6.4.2.6 Other a) The surface of the workbench shall be a seamless or sealed surface. Should be impervious to water, corrosion and heat.
b) The furniture in the laboratory should be simple, open and firm. There is space between the test bench, safety cabinet and other equipment to enable cleaning and disinfection. Chairs and other surfaces should be covered with non-fibrous materials to make them easy to disinfect. The corners and protruding parts of furniture and equipment should be smooth and burr-free, and should be rounded.
c) Install a non-manually operated or automatic hand basin in the safety cabinet room, near the door of the inside and outside changing rooms.
d) The communication system must be provided between the laboratory and the outside. A closed-circuit television system should be provided.
e) Information such as laboratory records in the laboratory must be sent to the laboratory via a fax machine.
6.4.3 Special requirements for the design and construction of a positive pressure suit laboratory
6.4.3.1 Site selection: The laboratory shall be constructed in a separate building or in a separate area within the laboratory building.
6.4.3.2 Plane layout
a) The core area of ​​the laboratory consists of a room (main laboratory) with a biosafety cabinet and a access channel. Access channels include dressing areas and disinfection areas. The dressing area is followed by an outer dressing room, a shower room and an inner dressing room. The disinfection area is a chemical shower room. When the staff leaves the main laboratory, they first pass the chemical shower to disinfect the surface of the positive pressure protective clothing. There is an automatic interlock between any adjacent doors in the core area to prevent two adjacent doors from being opened at the same time. For materials, articles and equipment that cannot be carried into and out of the main laboratory from the locker room, an autoclave with a double door structure, a soaking tank, a fumigation chamber or a ventilation transfer window with a disinfecting device should be placed on the main laboratory wall. For transfer or disinfection. An emergency exit channel with an airlock chamber must be provided.
b) Same as the requirements in 6.4.2.2 b) of this standard.
6.4.3.3 Enclosure structure: Same as the requirements of the paragraphs in 6.4.2.3 of this standard.
6.4.3.4 Ventilation and air conditioning a) The experimental area must maintain the highest degree of negative pressure, and its relative pressure should not be higher than 80 Pa; the relative pressure of the experimental area, chemical disinfection shower room, inner locker room, shower room and outer dressing room Increasingly, the pressure difference between 10Pa and 15Pa is maintained between adjacent rooms. The air cleanliness in the core area is preferably from seven to eight.
b) Except for the above clauses, the other requirements are the same as those in paragraphs 6.4.2.4 of this standard.
6.4.3.5 Safety devices and special equipment a) The main laboratory must be equipped with a biological safety cabinet of at least Class II. ,
b) Workers entering the main laboratory must wear positive pressure protective clothing and a life support system protected by a high efficiency filter to supply breathing gas. The life support system includes a positive pressure air supply unit that provides excess breathing gas, an alarm and an emergency support gas tank. The air pressure in the overalls is a constant positive pressure relative to the surrounding environment. An emergency power supply that is automatically started must be set up for the life support system.
c) Except for the above provisions, the requirements are the same as those in paragraphs 6.4.2.5 of this standard.
6.4.3.6 Others: Same as the requirements of the paragraphs in 6.4.2.6 of this standard.
3.6
Class II biosafety cabinet classIIbiosafetycabinet
At least one high-efficiency air filter is installed to purify the exhaust gas, and the working space is a vortex-free unidirectional flow air purified by a high-efficiency filter. When working, the front glass sliding window is opened halfway, the upper part is the observation window and the lower part is the operation window. The outside air is sucked in by the operating window and is not likely to escape from the operating window. Observing the operating procedures under working conditions not only protects the staff from infringement, but also ensures that the subject is not contaminated.
3.7
Class III biosafety cabinet classIII biosafetycabinet
At least one high-efficiency air filter is installed to purify the exhaust gas, and the working space is a vortex-free unidirectional flow air purified by a high-efficiency filter. The upper part of the front is the observation window and the lower part is the glove box type operation port. The inside of the box is kept under negative pressure. It ensures that the human body is completely isolated from the contents of the cabinet.