Rust is a common concern when metal is left to be exposed to the outdoor elements, such as on metal fire escapes attached to large buildings. An understanding of the various causes of rust in San Francisco, CA and general maintenance tasks you can perform can help you prevent issues with rust and degradation in the long term.
Here’s a look at what you should know.
Causes of rust
Rust is the result of a chemical reaction called “oxidation,” in which iron reacts with water and oxygen to create hydrated iron (III) oxide. In this process, the metal is returning to an unrefined state. This occurs because oxygen and iron have opposite charges, causing them to gravitate each other, but also resulting in iron transferring some of its electrons to oxygen atoms (the oxidation process), which results in the iron developing a flaky sort of coating.
The process can be faster in certain environmental settings, as well as with exposure to certain types of chemicals and with fluctuations in temperature. This is why it’s always a good idea to store bikes and metal gardening tools in a garage, shed or basement rather than outside.
How to prevent rust
The best way to prevent the formation and spread of rust is to keep metal items sheltered from the elements. However, that’s not always going to be feasible, especially when you’re dealing with large items or permanently affixed structures, like fire escapes.
If you have a permanent exterior metal structure, here are some of the best methods of rust prevention you can employ:
- Alloys: Using alloys like stainless steel rather than other types of metal that are more susceptible to oxidation is one of the most commonly used methods to prevent rust, or at least slow its spread. While this isn’t always an economical or sensible option, it’s a reliable one.
- Apply an oil: An oil coating can help to prevent or slow the spread of rust, because it will keep moisture from getting to the metal in the iron. However, this can be a poor health or environmental choice in certain applications.
- Paint the metal: A high-quality metal paint can prevent moisture from getting directly to the metal.
- Coat the metal: Applying a dry rust preventative product will form a barrier over the metal equipment or parts you need to protect. You can also use powder coating for metal products that will be kept outside. This will create a layer of vinyl, epoxy or acrylic over the metal that will prevent moisture from getting to it.
- VCI: Vapor corrosion inhibitors (VCI) are a popular method of protecting metal against rust. This chemical compound can protect metals by emitting rust-preventing vapors into enclosed air spaces. This is most commonly a solution used for packaging, rather than open air installation or storage.
- Galvanizing: Galvanizing coats iron in zinc to better protect it from corrosion. The zinc will corrode at a much slower rate than iron.
For more information about how to prevent the spread of rust on your fire escape in San Francisco, CA, contact Great Escape Fire Escape Service today.