Corrosion is defined as any change in the physical or chemical properties of materials such as ceramics, metals, alloys, plastic, etc. In other words, corrosion can occur in any physical object. There is another term known as rusting. It is also a type of corrosion. You can say that rust is the type of corrosion in iron and its alloys. But, most people use these two terms interchangeably. We will be discussing the basic differences between corrosion and rusting. Besides that, we will also be talking about the impact of rusting in the medical sector and the ways to minimize the formation of rust.
Differences between corrosion and rust
The term corrosion is used interchangeably with rust in most cases. However, there are few differences between corrosion and rust. So, we will see the differences between corrosion and rusting.
|Corrosion includes rust.||Rust is a type of corrosion.|
|It is the degradation of any kind of material.||It refers to the degradation of the iron and its alloys such as stainless steel.|
|The degradation can be chemical or physical.||The degradation is chemical. It refers to the oxidation of iron in the presence of air and moisture.|
|Corrosion can have any color.||The rust looks brown in color.|
Corrosion can be differentiated on the basis of different parameters. On the basis of the process of corrosion, location of the formation, and the size, the types of corrosion are stated below.
1. Based on the process
- Wet Corrosion:- Based on the oxygen and humidity of the environment. Mostly this occurs in machines such as autoclaves, water baths, incubators, etc.
- Dry Corrosion:- Based on the reaction of different gases with metal at high temperatures. Mostly this occurs in machines such as muffle furnaces, fume hoods, etc.
2. Based on the location
- Uniform:- This occurs throughout the surface of the body. The term ‘uniform’, does not refer to the equal corrosion throughout the object. Rather it means that corrosion spreads on all the parts of the surface.
- Localized:- This type of corrosion does not spread throughout the object. Rather it is confined at a particular site on the object.
3. Based on the size
- Macroscopic:- The corrosion is visible to the naked eyes. Thus, it mainly refers to one of the two possible cases. The first one is that the corrosion is big enough to be visible. Another reason can be that the corrosion is external.
- Microscopic:- The corrosion is invisible to the naked eyes. Thus, it mainly refers to one of the two possible cases. The first one is that the corrosion is too small to be visible. Another reason can be that the corrosion is internal.
Effects of rust in health sectors
(Effects of Corrosion)
We can find rust everywhere including medical equipment in hospitals and pharmaceuticals. Water bath, stability chamber, humidity chamber, fume hood, etc., are some of the instruments which can rust quite easily. This has got a negative impact on the health sector.
- Rusting can cause contamination of the products. If this product is consumed, it will harm human health. Similarly, if the contamination occurs in the QC and R&D rooms of the pharmaceutical companies, it will cause drug failure. Rusting in the production department will cause the failure of the manufactured drug. Even in the case of microbiology, rusting will hinder media and cultures.
- Rusting will then cause a loss of time, money, and effort.
- Rusting will reduce the lifespan of the machines. It may lead to early leakage from machines such as water baths, etc. Similarly, water leakage may lead to a short circuit of the electronic components.
- It will reduce the aesthetic appearance of the materials.
- Loss of natural resources.
Prevention of Rusting
- Selection of the Material:- The best way to protect from corrosion is to choose the material wisely. For example, carbon steel undergoes corrosion quickly than stainless steel. If it is possible, choose material having high corrosion resistance such as stainless steel and aluminum for your medical and surgical equipment.
- Protection from Humidity:- As we know the rise in humidity means a rise in water vapor in the environment. So, keep your machines away from the water supply. Also, keep them away from chemicals such as HCL, NaCl, etc. They can corrode the machines quickly. Due to these two reasons, I firmly believe that the corrosion rate in the Terai region (hot region) is more than in the hilly region.
- Protective Coating:- Here in Nepal you can easily find oil-based paint coating known as ‘Enamel’, from the market. I had used it on the railings of my house about 10 years ago and I have not faced any rusting on it.
There are other methods of protecting the rust as well. Some of them are powder coating, sacrificial coating, corrosion inhibitors, design modification, etc.