Autoclaves are designed for steam sterilization surgical instruments, dressings and bottled liquids. Large-capacity autoclaves are used for sterilization of workwear and barothermal treatment of roughage in order to increase their palatability and nutritional value.
Autoclaves operating under pressure of non-toxic, non-caustic and non-explosive media at a wall temperature not exceeding 200 °C, in which the product of capacity and pressure does not exceed 980,665 Pa o m3, as well as autoclaves operating under pressure of caustic, toxic and explosive media at the same temperature, for which this product is no more than 49,033 Pa o m3, does not need to be registered with the Gosgortekhnadzor authorities.
Autoclaves are registered in a special book of registration and inspection of autoclaves, kept by the person responsible for the good condition and safe operation of autoclaves.
Persons who have reached the age of 18, who have undergone a medical examination and are found fit for this type of work, who have been specially trained and certified by a qualification commission, are allowed to work on an autoclave. The autoclave operator's knowledge is tested at least once every six years, and repeated instruction is carried out once every 3 months.
Autoclaves are installed in separate rooms, the area meeting the requirements Building codes and rules. Such a room should have natural light, transoms or vents, and supply and exhaust ventilation. The autoclave door should only open outwards and not be locked with a key during operation. Glazed doors are prohibited. The floor in the autoclave must be made of non-conductive material.
The autoclave is installed at a distance of at least 0.8 m from the wall and reliably grounded. Autoclaves must be equipped with:
pressure gauge located on the housing fitting or on the pipeline up to shut-off valves or on the control panel;
a safety valve installed on the water pipe or pipe directly connected to the autoclave;
shut-off valves on pipelines supplying and discharging water from the autoclave, and on pipelines supplying steam to the autoclave;
a device (valve, tap) to check the absence of pressure in the autoclave before opening it;
a thermometer installed on a pipe directly connected to the autoclave, or on the control panel;
an automatic control device on the steam supply pipeline with a pressure gauge and a safety valve on the lower pressure side after the reducing device; a pressure gauge must also be installed before the reducing device.
If the rules for operating autoclaves are violated, an explosion may occur, the causes of which may be:
malfunction of the pressure gauge or safety valve, resulting in the steam pressure exceeding the maximum permissible;
coating the walls with rust or a thick layer of scale;
fat entering the nutrient water (medium);
operation of untrained personnel or leaving the autoclave unattended.
It is forbidden to put the autoclave into operation if the grounding device, safety valve or pressure gauge is faulty; The autoclave jacket has cracks, is leaking steam, or is not filled with water to the required level.
At the end of sterilization, turn off the autoclave and open the steam-air valve located on the lid. After the pressure drops to zero (determined by a pressure gauge), loosen the hinged bolts crosswise. Then carefully lift the lid of the autoclave, avoiding thermal burns to the hands and face, the sources of which are heated surfaces and steam. Screw in the hinged bolts. It is prohibited to leave the autoclave unattended during operation and to raise the steam pressure above the permissible level. Inspection of the autoclave by the enterprise must be carried out every 60 loads, but at least once every 4 months. The results are recorded in the autoclave operation log. The operation of the double safety valve is checked at least once a month, the safety valve - at least once every 6 months, and the pressure gauges - annually.
1. GENERAL OCCUPATIONAL SAFETY REQUIREMENTS
1.1. The following persons are allowed to service sterilizers (autoclaves):
– at least 18 years of age;
– have passed a preliminary medical examination;
– having a certificate of passage in established deadlines training and certification on safe maintenance of sterilizers;
– having electrical safety group I;
– past induction training and initial training at the workplace.
An employee is allowed to independently service sterilizers after an internship for 8-12 shifts and a knowledge test safe methods and methods of performing work.
Repeated training for employees servicing sterilizers takes place once every 3 months. Periodic certification of knowledge of safety requirements when servicing sterilizers is carried out once a year.
1.2. When working in sterilization departments, a worker may be exposed to the following harmful and hazardous factors:
– increased temperature of the surfaces of equipment and materials;
– increased air temperature working area;
– high humidity air;
– increased voltage values in electrical circuit, the circuit of which can pass through the human body.
1.3. The employee must report any accident at the workplace to his immediate supervisor.
2. OCCUPATIONAL SAFETY REQUIREMENTS BEFORE STARTING WORK
2.1. Before starting work, put on sanitary clothing and tuck your hair under a hat. It is not allowed to pin sanitary clothing with needles, or to keep breakable or sharp objects in clothing pockets. It is not allowed to work without shoes.
2.2. Prepare the necessary tools to complete the upcoming work personal protection, tools and accessories, check their serviceability.
2.3. Check availability and serviceability protective grounding, safety valves, locking devices and control measuring instruments. Electric sterilizers must be connected to the electrical network through an autonomous switch or circuit breaker. Plugging the sterilizer into a power outlet is not allowed.
2.4. Check the serviceability of pressure gauges. Pressure gauges are not allowed for use in cases where:
– there is no seal or mark;
– the pressure gauge check period has expired;
– the pressure gauge needle does not return to the zero scale reading when it is turned off;
– the glass is broken or there is other damage to the pressure gauge, which may affect the accuracy of its readings.
2.5. All observed violations of labor safety requirements in the workplace, as well as malfunctions of equipment, devices, tools and personal protective equipment must be immediately reported to the immediate supervisor and not begin work until they are eliminated.
3. OCCUPATIONAL SAFETY REQUIREMENTS DURING WORK
3.1. Personnel servicing sterilizers are prohibited from:
give steam to the sterilizer or turn on the heating with the lid loose;
turn on the sterilizer when the water level is insufficient or there is no water in the steam generator tank;
open the sterilizer lid or loosen its fastening if there is excess pressure in the sterilizer;
work on a sterilizer that has defects that reduce its strength and stability;
work on the sterilizer after the deadline hydraulic test and pressure gauge checks;
leave the sterilizer unattended while it is operating.
3.2. It is allowed to open the sterilizer door when sterilizing any solutions in it no earlier than 30 minutes after the end of sterilization, being careful.
3.3. The sterilizer must be stopped:
– if the pressure in the sterilizer rises above the permitted limit;
– in case of malfunctions of safety valves;
– if cracks, bulges, or gaps in the sterilizer are detected, working under pressure; welds or their fogging, leakage into bolted connections, gasket rupture;
– when the liquid level drops below the permissible level;
– in case of fire;
– in case of malfunction or incomplete quantity of cover parts;
– in case of malfunction of safety interlocking devices, measuring instruments and automation equipment.
4. OCCUPATIONAL SAFETY REQUIREMENTS IN AN EMERGENCY SITUATION
4.1. If an emergency occurs, turn off the equipment, notify surrounding people of the danger, report to your immediate supervisor about the incident and act in accordance with his instructions.
4.2. In case of fire or fire, immediately notify fire department by phone - 01, begin to extinguish the fire using the available primary fire extinguishing means, report the fire to your immediate supervisor.
4.3. For victims of injury, poisoning, or sudden acute illness, provide first aid, following the instructions "" (I 01-2014), if necessary, call an ambulance medical care by phone - 03.
5. OCCUPATIONAL SAFETY REQUIREMENTS AFTER WORK COMPLETION
5.1. Turn off the equipment, make sure there is no pressure in the sterilizers.
5.2. Make appropriate entries in the maintenance log.
5.3. Report any deficiencies discovered during work to your immediate supervisor.
Autoclaving means the treatment of instruments, linen, chemical glassware and equipment, and other materials with hot steam at high pressure. Under these conditions, all bacteria and viruses die quite quickly, in less than an hour.
Autoclaving is a narrower term than sterilization. Sterilization also implies the destruction of all pathogenic microorganisms, but different methods can be chosen, including autoclaving. In addition, it happens:
chemical sterilization (various chemical reagents, for example, ethyl alcohol, gases, hydrogen peroxide, iodine compounds, chloramine, etc.);
ultraviolet sterilization, for example using bactericidal irradiators, Ambilife air disinfection units;
ultrasonic sterilization;
infrared radiation treatment;
sterilization in dry-heat cabinets (air sterilizers).
Autoclaving is carried out using special devices - autoclaves. Autoclaves vary in size, design, and purpose. In laboratories and medical institutions they are used for sterilization. On industrial enterprises Autoclaves are used to produce dyes, herbicides, rubber products, building materials, carbon fibers, metals, food products and much more. Household autoclaves for canning at home are also produced.
The principle of operation of the autoclave is based on the fact that at normal pressure water boils at +100 °C. With further heat supply, the water temperature does not increase, but intense steam formation begins. If the vessel is sealed, the steam pressure begins to increase. The temperature of water and steam begins to rise. In a balanced system, the evaporation process stops, and the resulting hot steam easily penetrates the cells of microorganisms, killing them.
Hot steam also kills spores. To increase the disinfection effect, many autoclave models are equipped with a system for removing air and oxygen contained in it. The fact is that oxygen can help protect some bacteria. On the contrary, steam in an evacuated autoclave has greater penetrating power.
There are autoclaves different designs, size, degree of automation, but they all consist of:
outer casing capable of withstanding high blood pressure;
covers with built-in pressure gauge and valve for reducing overpressure;
chambers with water generating steam (equipped with a tap to drain remaining water after finishing work);
chambers for sterilized materials and equipment, into which steam is supplied under pressure.
The heat supply can be either external, for example, from gas or electric stove, and built-in (electric heaters).
Working with an autoclave involves certain risks. An autoclave left unattended may explode. That is why autoclaving should only be carried out by specially trained personnel.
The autoclaving process begins by removing the lid of the device. 
with the sterilized items placed in it, seal hermetically and close all taps except the air outlet valve. Water is poured into the water chamber and the heaters are turned on. They wait until the chamber with the material being sterilized is filled with steam, which begins to displace the air. The pressure is raised to 1 atmosphere and the air is completely released. After this, the pressure (according to the pressure gauge) is adjusted to the required value and from this moment the countdown of the sterilization time begins.
After sterilization is completed, first turn off the heaters, then open the tap and release the steam. Only after the pressure gauge shows the value “0” can the lid be opened. All materials from the autoclave are immediately unloaded - they cannot be left there! The water from the chamber is drained and the autoclave is left to dry.
There are two main autoclaving modes:
1. More severe with a temperature of +132 °C and a pressure of 2 atmospheres. Sterilization time is 20 minutes. In this mode, dressings, glass, porcelain and stainless steel dishes, corrosion-resistant instruments, glass syringes, needles, tweezers, etc. are sterilized; underwear, workwear.
2. Gentle with a temperature of +120 °C and a pressure of 1.1 atmospheres. Time - 45 min. This is how products made from plastics (polypropylene, high-density polyethylene, polystyrene), rubber, and latex are sterilized.
In medical institutions and biological laboratories, the operation of the autoclave is periodically checked. To do this, during the next cycle of operation of the device, ampoules with benzoic acid are placed inside (becomes purple when heated to +120 °C) or with urea (melts at +132 °C). For a more accurate analysis, test tubes with saprophytes and their spores are placed in an autoclave, and then the laboratory checks whether they survived the procedure.
To make canned food tasty, choose only fresh and high-quality products. Wash glass jars, fill them with recipe ingredients and seal them tightly with metal lids. There is no need to pre-sterilize autoclave jars.
Loading cans into the autoclave
Place the sealed jars on the rack at the bottom of the canner. You can place jars in an autoclave in several layers. The next row of cans can be placed directly on the lids of the previous row.
If the autoclave is equipped with special pressure cassettes, the jars are installed in them according to the instructions that come with the device.
Attention! Important! Only one type of jar with the same lid should be installed in one layer!
Then pour into the autoclave cold water so that the free space to the top edge of the device is approximately 3-4 cm.
Preservation in an autoclave
Close the lid of the device, make sure that the O-ring is present. Close the lid. To ensure that the lid does not skew to the side and that it lies flat, tighten the nuts crosswise.
If the autoclave is supplied without cassettes that compensate for the difference in pressure in the jars and the device, pump air into the tank with a pump through the “nipple” until the pressure gauge shows 1 atm using a car or any other pump. Creating a pressure of up to 1 atm in the autoclave is necessary to maintain the integrity of the cans, since when heated, a difference in pressure is formed in the autoclave itself and inside the cans, and to check the tightness of the connection between the lid and the body.
If the autoclave is supplied with special pressure cassettes, pre-pumping is not necessary.
Turn on the heat. As it heats up, the pressure in the device will increase; we need 0.4 MPa, which corresponds to 120 °C. When the autoclave heats up to the desired temperature, the jars must be kept in this mode for the time recommended for canned products. For example, for meat it is about an hour, canned vegetables in an autoclave will be ready after 20 minutes of sterilization at the same temperature, pickled mushrooms must be cooked for 40-50 minutes at a temperature of at least 110 degrees.
Completion of sterilization
After the required time has passed, gradually reduce the pressure, gradually reducing the heat until the heat source is completely turned off. Allow the unit to cool to a temperature of no more than 30°C, then slowly release the pressure using the nipple. Do not allow sudden heating and cooling, sudden release or increase in pressure - the jars may burst.
Before opening the lid, check the pressure release valve once to make sure that the pressure in the autoclave and outside are equalized. If nothing happens, you can safely open the lid.
Canned food is ready!
Open the lid and remove the jars. One laying and bringing the canned food to cooking takes 3-3.5 hours. As a rule, experienced people do this in the afternoon and by the evening they turn off the autoclave and then leave it to cool in this position until the morning.
When the sun rises, you can take out the finished jars, which will then be a wonderful delicacy for your table!
After you have studied the instructions for using the autoclave, you can begin preparing dishes, including: fish and meat stews, vegetable preparations, homemade pickles, jams and preserves.
Sterilization modes
| Name of canned food | Can volume, ml. | Sterilization temperature, o C | Duration of sterilization, minutes |
| Canned meat | 350 | 120 | 30 |
| 500 | 40 | ||
| 1000 | 60 | ||
| Canned poultry meat | 350 | 120 | 20 |
| 500 | 30 | ||
| 1000 | 50 | ||
| Canned fish | 350 | 115 | 20 |
| 500 | 25 | ||
| 1000 | 30 | ||
| Canned vegetables | 350 | 100 | 10 |
| 500 | 15 | ||
| 1000 | 20 | ||
| Marinated mushrooms | 350 | 110 | 20 |
| 500 | 30 | ||
| 1000 | 40 |
Sterilization by boiling.
Sterilization by boiling is carried out in a sterilizer. Distilled water is poured into the sterilizer, since tap water forms scale. (Glass objects are immersed in cold, metal objects-in hot water with the addition of sodium bicarbonate). The items to be sterilized are boiled over low heat for 30-60 minutes. The beginning of sterilization is considered to be the moment the water boils in the sterilizer. At the end of boiling, the instruments are taken with sterile tweezers, which are boiled along with other items.
Dry heat sterilization.
Dry heat sterilization is carried out in a Pasteur oven. The material prepared for sterilization is placed on the shelves so that it does not come into contact with the walls. The cabinet is closed and then the heating is turned on. The duration of sterilization at a temperature of 150°C is 2 hours, at 165°C – 1 hour, at 180°C – 40 minutes, at 200°C – 10-15 minutes (at 170°C paper and cotton wool turn yellow, and at more high temperature charred). The beginning of sterilization is considered to be the moment when the temperature in the oven reaches required height. At the end of the sterilization period, the oven is turned off, but the cabinet doors are not opened until completely cooled, since cold air entering the cabinet can cause cracks to form on hot dishes.
Steam sterilization under pressure.
Steam sterilization under pressure is carried out in an autoclave. The autoclave consists of two boilers inserted one into the other, a casing and a lid. The outer boiler is called a water-steam chamber, the inner boiler is called a sterilization chamber. Steam is generated in a water-steam boiler. The material to be sterilized is placed in the inner cauldron. There are small holes in the top of the sterilization boiler through which steam from the water-steam chamber passes. The autoclave lid is hermetically screwed to the casing. In addition to the main parts listed, the autoclave has a number of parts that regulate its operation: pressure gauge, water meter glass, safety valve, outlet, air and condensation valves. The pressure gauge is used to determine the pressure created in the sterilization chamber. Normal atmospheric pressure(760 mm Hg) is taken as zero, therefore, in an idle autoclave, the pressure gauge needle is at zero. There is a certain relationship between the pressure gauge readings and temperature (Table 1).
The red line on the pressure gauge scale determines the maximum working pressure, which is allowed in an autoclave. Safety valve serves to protect against excessive pressure increases. It is set to a given pressure, that is, the pressure at which sterilization must be carried out; when the pressure gauge needle crosses the line, the autoclave valve automatically opens and releases excess steam, thereby slowing down the further rise in pressure.
On the side wall of the autoclave there is a water gauge glass showing the water level in the water-steam boiler. There are two horizontal lines on the water meter glass tube - lower and upper, indicating the permissible lower and upper water levels in the water-steam chamber, respectively. The air valve is designed to remove air from the sterilization and water-steam chambers at the beginning of sterilization, since air, being a poor heat conductor, disrupts the sterilization regime. At the bottom of the autoclave there is a condensation tap to free the sterilization chamber from condensate formed during the heating period of the sterilized material.
Rules for working with an autoclave.
Before starting work, inspect the autoclave and control equipment. In autoclaves with automatic steam control, the arrows on the electric vacuum pressure gauge of the water-steam chamber are set in accordance with the sterilization mode: the lower arrow is set to 0.1 atm. lower, upper - by 0.1 atm. above the operating pressure, the water-steam chamber is filled with water to the upper mark of the measuring glass. During the period of filling with water, the valve on the pipe through which steam enters the chamber is kept open to allow free air exit from the boiler. The sterilization chamber of the autoclave is loaded with the material to be sterilized. After this, the lid (or door) of the autoclave is closed, tightly secured with a central lock or bolts; to avoid distortion, screw the bolts crosswise (along the diameter). Then turn on the heating source ( electric current, steam), closing the valve on the pipe connecting the steam source to the sterilization chamber. With the beginning of steam formation and the creation of pressure in the water-steam chamber, purging is carried out (removing air from the sterilization boiler). The method of air removal is determined by the design of the autoclave. At first, the air comes out in separate portions, then a smooth, continuous stream of steam appears, indicating that the air has been completely displaced from the sterilization chamber. After removing the air, the tap is closed, and a gradual increase in pressure begins in the sterilization chamber.
The beginning of sterilization is considered to be the moment when the pressure gauge needle shows the set pressure. After this, the heating intensity is reduced so that the pressure in the autoclave remains at the same level for the required time. At the end of the sterilization time, heating is stopped. Close the valve in the pipeline supplying steam to the sterilization chamber, and open the valve on the condensation (down) pipe to reduce the steam pressure in the chamber. After the pressure gauge needle drops to zero, slowly loosen the clamping devices and open the lid of the autoclave.
The temperature and duration of sterilization are determined by the quality of the material being sterilized and the properties of the microorganisms with which it is infected.
Temperature control in the sterilization chamber is carried out periodically using bacteriological tests. Biotests are produced by the bacteriological laboratories of the Center for Sensitive Sciences. If these tests are not passed, an inspection is carried out technical condition autoclave
