Grounding equipment

Toluene is a notoriously poor electrical conductor even in grounded equipment it has caused several fires and explosions from static electricity. Near normal room temperature it has a concentration that is one of the easiest to ignite and, as previously discussed, that generates maximum explosion effects when ignited (Bodurtha, 1980, p. 39). Methyl alcohol has similar characteristics, but it is less prone to ignition by static electricity because it is a good conductor. Acetone is also a good conductor, but it has an equihbrium vapor pressure near normal room temperature, well above UFL. Thus, acetone is not flammable in these circumstances. 

Klinkenberg, A., Production of static electricity by movement of fluids within electrically grounded equipment, Proceedings Fourth World Petroleum Congress, Sect VII-C. Paper No. 5. 253-64, Carlo Colombo, Rome, 1955. 

As a result of its use as an insecticide on cotton, fruit trees, vegetables, and other crops, methyl parathion is released directly to the atmosphere during application. It is applied primarily by spraying from aircraft or ground equipment (NPIRS 1986). Aerial application of methyl parathion to agricultural fields releases the insecticide to the air. 

Yates, W.E., N.B. Akesson and D.E. Bayer. 1977. Drift of glyphosate sprays applied with aerial and ground equipment. Weed Science 26(6) 597-604. 

These are sprayers that use special pesticide concentrates. They may be used in agricultural, ornamental, turf, forestry, right-of-way, biting fly, and some structural pest control operations. ULV sprayers may be hand-held or mounted on either ground equipment or aircraft. 

Apparel of children that contain components that can be caught on doorknobs, play ground equipment, or protrusions. 

Preparative chromatography should always be carried out in well-ventilated areas. When using large amounts of electrostatic solvents, e.g., hexane, care should be taken to ground equipment and prevent fires due to electrostatic discharge. Heptane is safer than hexane (seeTable 5.3). 

Spray nozzles designed for both aircraft and ground equipment can also be used to enlarge droplet size of the spray. Application equipment can also be modified to reduce drift. For example, shrouding the spray booms of ground equipment keeps droplets from swirling up into the air, thus reducing the potential for drift and applicator exposure. 

Compared to some ground equipment, aircraft release sprays from greater heights. This may increase the drift potential... 

Control static buildup (materials, dissipatives). = Ground equipment. 

Site and Application Procedures. The orchard site and air application equipment were the same as described by Currier (1982). In 1980, ground applications were made with an Ag-Tech low volume air blast sprayer, calibrated to deliver 187 1/ha, and in 1981, with a Kinkelder low volume air blast sprayer calibrated to deliver 94.6 1/ha. From previous studies of MacCollom et al ( ) and Currier ( ) it was known that the air application gave a median droplet size diameter of 100 to 150 pm. Estimation of particle size, as measured on water sensitive paper, for ground equipment was 75 to 110 pm. Application rates for captan 80W in both years was 3.12(AI) Kg/ha, and for carbaryl 80S, 2.24(AI) kg/ha. 

Figure 2. Carbaryl/captan applications by ground equipment in presence and absence of a temperature Inversion.

From these studies it is apparent that more drift occurs from air application than ground equipment. The presence of a temperature inversion at the time of application usually results in greater off-target downwind deposition (regardless of slopes of <2%) at the study site. The absence of an inversion with slight turbulence results in reduced downwind drift and less variability in deposits. 

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