TYPES OF FUMIGATION - VERTICAL STORAGES - TABLETS
FUMITOXIN tablets and pellets are used to protect stored commodities fromdamage by insects and other vertebrate pests. Fumigation of stored products with FUMITOXIN in the manner prescribed in the labeling does not contaminate the marketed commodity. FUMITOXIN metal phosphide fumigants are acted upon by atmospheric moisture to produce phosphine gas.
Phosphine gas is highly toxic to insects, burrowing pests, humans, and other forms of animal life. In addition to its toxic properties, the gas will corrode certain metals and may ignite spontaneously in air at concentrations above its lower flammable limit of 1.8% (v/v). These hazards will be described in greater detail later on in this Applicator’s Manual.
These gases are essentially nonflammable and act as inerting agents to reduce fire hazards.
FUMITOXIN is prepared in two spherical shapes. The rounded tablets weigh approximately 3 grams and will release 1 gram of phosphine gas. They are about 16mm in diameter. The pellets are about 10 mm in diameter, weigh approximately 0.6 gram and release 0.2 gram of phosphine gas.
FUMITOXIN Tablets are provided in 21kg cases, contain 14 resealable, gas-tight flasks of 500 tablets each or, 70 flasks of 100 tablets each.
FUMITOXIN Pellets are provided in 21kg cases containing 14 resealable, gas-tight flasks of 1660 pellets each or, 14 flasks of 2490 pellets each.
Upon exposure to air, FUMITOXIN pellets and tablets begin to react with atmospheric moisture to produce small quantities of phosphine gas. These reactions start slowly, gradually accelerates and then tapers off again as the aluminum phosphide is spent. FUMITOXIN pellets react somewhat faster than do the tablets. The rates of decomposition of the tablets and pellets will vary depending upon moisture and temperature conditions. For example, when moisture and temperature of the fumigated commodity are high, decomposition of FUMITOXIN may be complete in less than 3 days.However, at lower ambient temperatures and humidity levels, decomposition of FUMITOXIN may require 5 days or more. After decomposition, FUMITOXIN leaves a gray-white powder composed almost entirely of aluminum hydroxide and other approved inert ingredients. This will cause no problems if the fumigant has been added directly to a commodity such as grain. However, the spent powder must usually be retrieved for disposal after space fumigations. If properly exposed, the spent FUMITOXIN will normally contain only a small amount of unreacted aluminum phosphide and may be disposed of without hazard. While spent FUMITOXIN is not considered a hazardous waste, partially spent residual dusts from incompletely exposed FUMITOXIN will require special care..
FUMITOXIN tablets and pellets are supplied in gas-tight containers and their shelf life is unlimited as long as the packaging remains intact.Once opened for fumigation, the aluminumflasks of tablets or pelletsmay be tightly resealed and stored for future use.
Recommended FUMITOXIN Dosages for Various Types of Fumigation
One (1) FUMITOXIN tablet or five (5) FUMITOXIN pellets will produce a concentration of 25 parts per million (ppm) of phosphine gas (PH3) in a volume of 1000 cubic feet. (1 gram PH3/1000 cu.ft. is equivalent to 25 ppm).
Although it is permissible to use the maximum dosage listed above, the following recommended dosage ranges can be used as a guideline for various types of fumigation. When a dosage range is recommended, use the higher rate under conditions of severe infestation, lower temperature and other applicable variables.
Higher dosages are recommended in structures that are of loose construction and in the fumigation of bulk stored commodities in which diffusion will be slowed and result in poor distribution of hydrogen phosphide gas.