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Formaldehyde solution is drying to the skin and the 

 vapors or fumes are irritating to mucous membranes and 

 eyes. It is very toxic to plants and should only be used 

 in empty storages, grading rooms or on empty containers. 



Formaldehyde fumes or vapors are fungicidal and bacteri- 

 cidal and will kill blue mold spores as well as other 

 storage rot fungi. The dosages given here are for the 

 amount of formalin (the commercial 37% formaldehyde solu- 

 tion) to use. It may be applied as a spray or used to 

 generate formaldehyde gas for decontamination of empty 

 containers, storage rooms, and grading rooms. By "empty" 

 we mean no agricultural products, plants or other forms 

 of life, like animals. Once a squash grower asked how to 

 disinfect a storage with formaldehyde. He did not say it 

 was full of squash. It was assumed that the storage was 

 empty and he was told how to do it. He ended up with a 

 storage full of damaged squash. 



As a Spray 



1 gallon of formalin to 50 gallons of water. You will 

 need 1 pint of formalin for each 1000 cubic feet of con- 

 fined space. Empty apple boxes, lugs, crates, picking 

 baskets and equipment to be disinfected can be assembled 

 in a pile outside where it can be covered with a plastic 

 tarp to confine the formaldehyde fumes. In a sunny loca- 

 tion, the tarp will trap heat and there will be better 

 disease kill. 



Wet down the pile with water - it will give better dis- 

 ease kill, spray with the formaldehyde solution, and cover 

 with the tarp . 



After 24 hours, the tarp can be removed or it can be left 

 on which will delay recontami nation , until a few days be- 

 fore the materials in the pile are to be used. The formal- 

 dehyde fumes will evaporate and dissipate in a few days 

 after the tarp is removed and there will be no residue to 

 harm the apples later. 



Storage Rooms (with empty boxes, crates or other equipment) and 

 Packing Rooms (with equipment and empty containers). 



Wet down walls, ceilings, and materials to be decontami- 

 nated with water for better kill. Spray or wet everything 

 down with the required amount of formaldehyde solution. 

 You need 1 pint for each 1000 cubic feet of space to be 

 fumigated. One gallon in 50 gallons of water will do 

 8000 cubic feet. The temoerature of the packing room or 

 storage room should be 65 F or higher. 



