subject: Using Lime Plaster Safely [print this page] Lime has been used as building material for more than 11,000 years. Ancient Mayan builders and Roman architects frequently used lime to plaster floors, walls, and the exterior of buildings. Some of these buildings are still standing today which is a testament to the enduring strength of lime plasters.
If you planning to use lime plasters for your construction projects, then you are on the right track. Aside from the durability of this material, lime is also highly recommended for building green structures.
Experts believe that the use of lime for residential and industrial construction projects could significantly reduce the release of carbon dioxide in the atmosphere. This will greatly help in further reducing the devastating effects of global warming.
Although a suitable construction material for building green structures, you still have to follow the basic safety procedures when handling lime. To better understand how to use lime plasters safely, you have to know its chemical composition.
The Chemistry of Lime Plasters
Lime plasters are primarily made from calcium hydroxide. It is mixed with sand or other inert fillers. With the help of carbon dioxide, the calcium hydroxide will be transformed into limestone.
Calcium hydroxide is usually available in white powder. If mixed with water, a sticky paste can be made from it. You can keep the lime paste in an air tight container before use. Once the paste is exposed to air, it will slowly transform and harden into limestone again. This permanently sets the plaster.
Safety Precautions When Handling Lime
When wet, lime has a pH of 12 it means that this material is extremely caustic. This can damage your skin and could induce irritation. If you are handling lime, it is important to wear protective construction goggles in order to protect your eyes. You must also wear adequate protective clothing and rubberized gloves to prevent exposing your skin to lime splatters.
If you are going to prepare powdered calcium hydroxide into a paste, it is a must to use a basic face mask that can filter industrial dusts. Direct inhalation of this powder can damage your lungs and respiratory system.
As a safety measure, you should have a pail of clean water nearby when working with lime plasters. If lime accidentally gets into your eyes, you should immediately wash the affected area thoroughly in order to neutralize it. For direct skin contact, you can neutralize lime with vinegar or lemon juice.
