Physan 20 VS Chlorine Bleach as a Disinfectant:

Many growers recognise the importance of disinfection in the greenhouse. However, many mistakenly believe that chlorine bleach is a cheaper alternative that provides quality disinfecting capabilities. This is not so.

Chlorine bleach is not labeled for use as a greenhouse disinfectant by the EPA on a state or federal level. Its use as such can result in citations and or fines upon inspection.

Bleach rapidly evaporates when prepared in solution. The half-life of a .5%solution of bleach and water is only 2 hours. Thus the prepared solution must be applied immediately after mixing to be effective. In addition, a contact time of 30 minutes is required for disinfection.

Physan 20 has residual germicidal activity, which means it remains effective for a period of time, particularly on hard surfaces. The solution itself remains active and can be used over time. Its effectiveness can be checked with Physan 20 Test Strips to ensure it remains active. In addition, a 10 minute contact time is all that is required to disinfect.

The use of a bleach solution stronger than .5% can cause damage to plastics and metal. In addition, bleach presents a risk to employees who inhale the fumes or splash the product on clothing.

The diluted Physan 20 solution is safe enough to dip ones hands in. It is not a primary eye or skin irritant, and if splashed on clothes will not harm them. The solution is pleasant smelling and requires no special ventilation to use.


Please Download Physan 20 Technical Data for more information.



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