Application of cleanroom technology in medical environment

Clean technology is also known as clean room technology. In addition to meeting the normal temperature and humidity requirements of air-conditioned rooms, the indoor particulate content, airflow, pressure, etc. are also controlled within a certain range through various facilities and strict management of engineering technology. Such a room is called a clean room. With the development of medical and health services and high technology, clean technology is more widely used in the medical environment, and its technical requirements are also higher. The clean rooms used in medical treatment are mainly divided into three categories: clean operating rooms, clean care wards and clean laboratories.

Clean operating room

Clean operating room takes indoor microorganisms as the control target, operating parameters and grading indexes, and air cleanliness is the necessary guarantee condition. Clean operating room can be divided into the following levels according to cleanliness:

1. Special clean operating room: the cleanliness of the operation area is 100 and the surrounding area is 1000. Suitable for burn, joint conversion, organ transplantation, brain surgery, ophthalmology, plastic surgery and heart surgery, etc.

2. Clean operating room: the cleanliness level of the operating area is 1000, and the surrounding area is 10000, which is suitable for aseptic operations such as thoracic surgery, orthopedic surgery, urology, hepatobiliary and pancreatic surgery, bone surgery and egg extraction;

3. General clean operating room: the cleanliness of the operating area is 10,000, and the surrounding area is 100,000, which is suitable for general surgery, dermatology, abdominal surgery and other operations;

4. Quasi-clean operating room: the air cleanliness is 100,000, suitable for obstetrics, anorectal surgery and other operations.

Clean operation department room in addition to cleanliness level and bacterial concentration should meet the corresponding level, the relevant technical parameters should also meet the relevant provisions, see the clean operation department at all levels of the main technical parameters table.

According to general requirements, the plane layout of the clean operation department should be divided into two parts: clean area and non-clean area. Operating rooms and functional rooms directly serving operating rooms shall be located in clean areas. Airlock, buffer room or transfer window should be set when people and objects pass through different cleanliness areas in the operation department. The operating room is usually located in the core. The internal plane and channel form should conform to the principle of functional flow and clear pollution.

Several clean care wards in a hospital

The clean care unit is divided into isolation unit and intensive care unit. According to the biological risk, isolation wards are divided into four grades: P1P2P3P4.

P1 wards are basically the same as ordinary wards and are not specifically prohibited from entering or leaving.

P2 ward is more strict than P1 ward.

P3 ward is isolated from the outside by the heavy door or buffer room, with negative pressure inside the room;

P4 ward is separated from the outside world by the isolation area, with a constant indoor negative pressure of 30Pa.

Medical staff should wear protective clothing to prevent infection. There are ICU (intensive care unit), CCU (cardiovascular care unit), NICU (premature care unit), leukemia room and so on. The room temperature of the leukemia room is 242, the wind speed is 0.15 ~ 0.3/m/s, the relative humidity is below 60%, the cleanliness is 100 level, at the same time, the cleanest air should be sent to the head of the patient first, so that the mouth and nose breathing area in the air supply side, the use of horizontal flow is better.

The results of bacterial concentration measurement in burn ward showed that vertical laminar flow was superior to open treatment. The laminar injection rate was 0.2m/s, the temperature was 28 ~ 34, and the cleanliness was 1000 degrees. Respiratory ward is rare in the domestic, the ward is strict with the indoor temperature and humidity, temperature control in the slaughter of 23 to 30, 40 ~ 60% relative humidity, each unit can be adjusted according to patients' own, control between 10 ~ 10000 level of cleanliness, noise is less than 45 db (A), personnel should be subject to change clothes into the room, blowing tube and other physical purification, ward to maintain positive pressure.

Clean laboratory

Clean laboratory is divided into general clean laboratory and biosafety cleanroom laboratory. The experiment in common clean laboratory is not infective, but requirement environment does not cause bad effect to experiment itself, because this experiment room does not set protective facilities, and clean degree must reach experiment requirement.

Biosafety laboratory is equipped with primary protection facilities, which can realize the biological experiment of secondary protection. Biosafety laboratories are required for scientific experiments in the fields of microbiology, biomedicine, functional experiments and gene recombination. The core of biosafety laboratory is safety, which is classified into four grades of P1, P2, P3 and P4 according to the degree of biological hazard.

P1 laboratory is suitable for very familiar disease sources, which do not often cause healthy adult diseases and pose little risk to experimenters and the environment. In the experiment, the door should be closed and operated in accordance with the general microbial experiment.

P2 laboratories are suitable for sources of moderate risk to humans and the environment. Restricted access to the experimental area, aerosol experiments should be conducted in a class II biosafety cabinet, equipped with autoclave sterilizer;

P3 laboratories are used in clinical, diagnostic, teaching, or production facilities to carry out work on endogenous and exogenous sources of disease that, if exposed and inhaled, can cause serious and potentially fatal diseases. The laboratory is equipped with double cleanroom doors or air lock Chambers and an external isolated test area, which is forbidden to be entered by non-staff of the laboratory. The laboratory is under full negative pressure, and the class II biosafety cabinet is used for experiments. The indoor air is filtered by high efficiency filter and then transferred to the outside.

P4 laboratory is more strict than P3 laboratory. Some dangerous exogenous diseases have a high individual risk of laboratory infection and life-threatening diseases caused by aerosol transmission. Related work should be carried out in P4 laboratory. Independent structure of internal isolation area and external partition is adopted. Negative pressure is maintained inside the building.

Class III biosafecurity cabinet is used for experiments. The core of biosafety laboratory design is dynamic isolation, and exhaust measures are the key points, which emphasize on on-site disinfection, attach importance to sewage diversion and prevent accidental diffusion, and require appropriate cleanliness.The construction of purification device in hospital clean room in China is at the promotion stage. In recent years, major hospitals in major cities have built or rebuilt clean rooms, or added or renovated the original clean room system, which reflects China's economic development, scientific and technological progress and improved medical and health standards.

It is a very prudent work to build and rebuild clean rooms, reduce infection rate and improve curative effect. At the current technological and economic level, the conditions for implementation have been met, but it should be carried out gradually under the overall planning of local health authorities. At the same time, it should be noted that in the new or expansion projects of hospital clean rooms in recent years, some units and relevant departments often only focus on whether the clean room has been installed, ignoring the quality of clean room equipment.

Hospital clean room is different from electronic clean room and pharmaceutical clean room, it has higher cleanliness requirements, if the clean room device can not meet the requirements of cleanliness, resulting in internal hospital infection, it will endanger the patients and medical staff. Therefore, professional construction units of hospital clean technology engineering should be employed to design and construct hospital clean rooms, so as to ensure the high quality construction of each clean room.