Cleaning greenhouses with fluoride based agents
The horticultural sector often uses a cleaning agent based on fluoride to clean glass. Fluoride chemically cleans the surface of the glass. Several minutes after application the treated glass along with the dirt is rinsed off. But this principle should not be applied to synthetic greenhouse roof coverings.
In recent years more and more types of greenhouse roof coverings have appeared on the market. Toughened or diffuse glass and glass with a special coating such as an anti-reflective coating certainly shouldn’t be cleaned with a substance containing fluoride. The treatment can lead to irreparable damage to the greenhouse roof material. With diffuse and toughened glass it is essential to spray a small area on both sides of the glass with the fluoride containing cleaning agent. Judge the glass after rinsing and drying to see if any damage has occurred. If there is any doubt inquire with the glass manufacturer about whether it’s wise to clean it using a fluoride-based product. Glass covered in a permanent coating, for example an anti-reflective coating, should never be cleaned with agents containing fluoride. The coating will definitely suffer irreparable damage. It is also important to know that products containing fluoride should not be allowed to dry on the glass: The surface of the glass should be well rinsed with clean water before the cleaning agent has a chance to dry.
It is essential therefore to have information about the type of roof covering when using cleaning agents containing fluoride. The type of crop being grown in the greenhouse should also be taken into account. Bulbs and tuber crops, such as freesia, lily and yucca are extremely sensitive to fluoride.
There are two types of fluoride-containing agents. Cleaners that are based on hydrogen fluoride dissolved in water and cleaners based on ammonium bifluoride.
Cleaning with hydrogen fluoride solutions
Hydrogen fluoride is a gas that dissolves in water. When applied to a product some of the gas is released. Gaseous hydrogen fluoride is highly toxic to people and is extremely harmful to some crops. A few gaseous products are still available on the market.
Cleaning with ammonium bifluoride solutions
Ammonium bifluoride has a much milder activity than the aggressive hydrogen fluoride. Ammonium bifluoride is a salt and hardly evaporates. For both the user as well for the crops in the vicinity of the greenhouse, ammonium bifluoride is a safer alternative. For many years Mardenkro has been selling two glass cleaning agents that fall into this category: GS-4 and GS-4 Xtra.
Protective clothing should be worn when working with fluoride products and the necessary safety measures need to be observed.
