Both achieve the same result, but do it in very different ways. An autoclave uses pressure and steam to sterilize the contents. It's quick and uses lower temps than air ovens. Hot air ovens use dry heat, high temperatures and longer times to achieve the same result.
Hot Air Oven: Takes a longer time to achieve effective sterilization, usually between 1 to 2 hours, as dry heat is less efficient at penetrating materials compared to steam. Autoclave: Has a much faster sterilization cycle, typically between 15 to 30 minutes.
There are a number of differences between dry heat sterilization and steam sterilization, the most obvious difference being that autoclaves use steam, vacuum, and pressure to clean tools and cages, while dry heat sterilization simply uses hot air.
Disadvantages of Hot Air Ovens
In comparison to the autoclave or other moist heat sterilization methods, a hot air oven has a lower heat capacity and it's slower in killing microorganisms. It's not suitable to sterilize all equipment, like plastic wares and heat-sensitive materials.
Specific temperatures must be obtained to ensure the microbicidal activity. The two common steam-sterilizing temperatures are 121°C (250°F) and 132°C (270°F). These temperatures (and other high temperatures)830 must be maintained for a minimal time to kill microorganisms.
Compared to dry heat, steam sterilization is more efficient because moisture is a superior heat conductor and can better penetrate the load. The combination of increased productivity and lower energy expenditure results in cost savings, making steam sterilization an attractive option for most laboratories.
The commonly-used temperatures and time that hot air ovens need to sterilize materials is 170 degrees Celsius for 30 minutes, 160 degrees Celsius for 60 minutes, and 150 degrees Celsius for 150 minutes.
The disadvantage of autoclaves is that they are unsuitable for heat-sensitive objects and repeated exposure to high humidity and heat may dull sharp, fine cutting instruments, particularly high-grade carbon steel edges of scissors and scalpel blades.
First, hot air ovens can Sterilize quickly and effectively. Second, they can be used to sterilize a wide variety of materials, including glassware, metals, and plastics. Third, hot air ovens help to prevent cross-contamination between materials.
Hot Air Oven are designed to generate heat with blower assisted air re-circulation inside the chamber at temperature from ambient+10°C to 150°C, 200°C or 250°C.
Both achieve the same result, but do it in very different ways. An autoclave uses pressure and steam to sterilize the contents. It's quick and uses lower temps than air ovens. Hot air ovens use dry heat, high temperatures and longer times to achieve the same result.
Autoclaving is the most effective and reliable means of sterilizing laboratory materials. Autoclaving sterilizes material using saturated steam under pressure (“moist heat”).
Hot air ovens are electrical devices which use dry heat to sterilize. They were originally developed by Louis Pasteur, and are essentially the same as fan ovens used for cooking food. Generally, they use a thermostat to control the temperature.
Autoclaves are usually much faster than other sterilization methods and can sterilize a variety of materials in a much shorter period of time. This means healthcare workers can spend less time sterilizing instruments and more time providing care to patients.
Hot air ovens use extremely high temperatures over several hours to destroy microorganisms and bacterial spores. The ovens use conduction to sterilize items by heating the outside surfaces of the item, which then absorbs the heat and moves it towards the center of the item.
Hot air ovens use dry heat at 160°C for 2 hours to sterilize materials like glassware and surgical instruments. Autoclaves use high-pressure steam at 121°C for 15 minutes, which is effective for liquids and heat-sensitive materials.
DISADVANTAGES OF HOT AIR OVEN
1) Approach that takes a long time since heat penetration and germ death happen slowly. 2) Most material cannot be with stand high temperature for example, plastic and rubber products cannot be dry heated Sterilized because the temperatures employed (160°-170°c) are to high for them.
1) Ensure that the fan is in working condition during the operation. 2) Do not spill any chemical or water on the tray of oven. 3) Tong should be use to place/remove the glassware or any material from the oven. 4) Ensure that the Exhaust blower is ON before starting the oven.
Hot air ovens are laboratory testing equipment that are used to sterilise materials such as glassware, chemicals, and sealed containers. They are also used for drying, baking, curing, and heat-treating various substances.
However, prions, such as those associated with Creutzfeldt–Jakob disease, and some toxins released by certain bacteria, such as Cereulide, may not be destroyed by autoclaving at the typical 134 °C for three minutes or 121 °C for 15 minutes and instead should be immersed in sodium hydroxide (1M NaOH) and heated in a ...
PROHIBITED ITEMS: Autoclaves must not be used with the following: ▪ Corrosives (e.g., acids, bases, phenol, etc.), solvents (e.g., ethanol, methanol, chloroform), or radioactive materials: Contact EHS or review the EHS Program Manual, Section 5.2 - Waste Disposal Procedures for proper decontamination and disposal ...
You can buy one for a few hundred dollars but you can also spend tens of thousands of dollars on an autoclave. What matters is the type of instruments that need to be sterilised. The price of an autoclave depends largely on its quality, features, chamber size, class, brand and warranty terms.
Hot air oven sterilizes objects such as glassware (test tubes, flasks, and pipettes), metal instruments (blades, scissors), powders (sulfadiazine, starch, zinc oxide), materials that have oil and glass test tubes.
All hot air ovens provide temperature range 5°C above ambient to 250°C with accuracy of ±2°C. Temperature is controlled with mechanical temperature control (rotary knob) or by digital control (PID controller). For uniform rotation of heat inside the chamber noise-less fan is used for air circulation.