Have you ever heard about moist heat sterilization? If not, this blog helps you to understand what is moist heat sterilization process.
What is the moist heat sterilization process?
It’s very simple, in moist heat sterilization high-pressure steam is applied to the object to kill bacteria, micro-organisms, fungi, viruses, and spores. Hot water vapor/steam act as a sterilizing agent in the moist heat sterilization process. Moist heat kills microorganisms by denaturation of structural proteins & irreversible coagulation.
Application of moist heat sterilization
The moist heat sterilization process is mainly used for surgical instruments like dental forceps, scalpels, bone chisels, surgical burs, Surgical scissors, and Various scalpels.
What kind of instruments are used in the moist heat sterilization process?
Well, it’s an autoclave. Autoclave works similarly to a pressure cooker where steam generates a heating coil of autoclave and closed enclosure build and increase the pressure inside autoclave.
Types of Autoclave
Please refer to the following image to understand the difference between horizontal (front-loading) and vertical autoclave (top loading).
Types of moist heat sterilization
Following 3 types of sterilization process widely used,
| Types of moist heat sterilization | Sub Type / Technical Name |
| 1. Below 100deg. centigrade | Pasteurization |
| 2. At 100deg. centigrade | 2.1 Boiling 2.2 Steam Sterilization |
| 3. Above 100deg. centigrade | Autoclave 3.1 Slow Exhaust: Medical waste and liquid 3.2 Fast Exhaust: Instruments, glass ware |
Moist heat sterilization process parameters
Following 4 process parameters used in the moist heat sterilization process,
| Process Parameters | Unit / Range |
| Time | Holding time 20 – 30 min |
| Sterilizing Agent | Moist heat |
| Pressure | 15 to 20 Psi |
| Temperature | 110 to 130 degrees centigrade |
| Water Level | Defined water level as per autoclave |
Pros & Cons of Moist Heat Sterilization Process
Yeah! Every process or technology subjected Pros (advantage) and Cons (disadvantage), same is with the moist heat sterilization process. Let’s review the pros and cons of the moist heat sterilization process.
Pros of Moist Heat Sterilization:
- Cost-effective and easy to sterilize in an autoclave
- Non-toxic, no radiation involved in moist heat sterilization
- Easy to monitor and control overall sterilization process
- Good penetration level
- Safe to use
Cons of Moist Heat Sterilization
- Not suitable for heat-sensitive objects like fiber optic, plastic, plastic packaging, and electronic instruments.
- Not suitable for moisture/humidity sensitive objects
- The high potential risk of rusting surgical tools.