Fumigators

Fumigators
To subject to smoke or fumes, especially of certain chemicals, usually in order to exterminate pests or disinfect pathogens
Precautions

1.      should have a physical examination at least once a year and more often if health conditions require such. Fumigation businesses should maintain up to-date health records for each employee.

2.       should abstain from alcoholic beverages and medical or recreational! drugs for 24 hours before and 24 hours after a fumigation job.

3.       Should NOT participate in a fumigation if they have colds or other respiratory problems that make breathing difficult.

4.      Should NOT participate in a fumigation while undergoing continuing medical or dental treatments unless authorized to do so by the physician or dentist in charge.

5.       Instruct all personnel in first aid and other emergency procedures, including personal decontamination

6.       Make sure fumigators understand the use of specific antidotes, first aid procedures, ana symptomatic relief measures.

7.       Instruct employees to report ail accidents immediately to the employer or supervisor. Caution personnel to report all indications of illness or physical discomfort regardless of their apparent minor nature Signs of illness may include but not be restricted to any or all of the following: dizziness, diarrhea, nausea, headaches and lack of coordination.

8.       Make sure employees understand the hazards that may be encountered because of carelessness or misuse of fumigants.

9.      Teach employees in the selection, operation, and maintenance of all protective equipment and safety procedures required by the fumigant of choice

Protective Equipment

Fumigators must use protective equipment to prevent injury or loss of life if they are likely to be exposed to gas levels above the allowable limits. Label requirements for protective clothing and equipment are related to threshold concentrations of the fumigants in fumigated spaces: therefore, fumigators need reliable detection devices to ensure health ana safety of personnel, as well as to comply with the law, because the pesticide label is a legal document. For information about specific detection devices, see the section on Use of Safety Devices, Analyzers, and Detectors. If the fumigant concentration in the fumigated area, as measured by a direct reading detector device, exceeds the threshold concentration specified by the ERA for that fumigant. all persons in the area must wear the protective equipment specified on the label. Such equipment will be either an NIOSH/MSHA approved self-contained breath-ino apparatus (SCBA) or a combination air-supplied/ SCBA respirator. Manufacturer's directions and specifications for SCBA's must be understood and followed Gas mask/canister combinations are also allowed under certain circumstances. Threshold concentrations for some space fumigants that may still be legally used are given below

Fumigant Threshold Concentration (ppm)

methyl bromide . . . . . . . . . . . . . . 5.0 (TLV)a

chloropicrin . . . . . . . . . . . . . . . . . 0.1 (TLV)

cyanide . . . . . . . . . . . . . . . . . . . . 10.0 (TLV)

hydrogen phosphide

(Phosphine) . . . . . . . . . . ... . . . . . 0.3 (TWA/TLV)b

sulfuryl flouride . . . . . . . . . . . . . . 5.0 (TLV)

Threshold Limit Value (a at any time during fumigation)  Time Weighted Average over an 8-hour period for Applicators If the concentration of methyl bromide in the area, as measured by a pump ana appropriate detector tubes (e.g.. Draeger, Kitagawa. MSA. and Sensidyne). Does not exceed 5 ppm, no respiratory protection is required. It this concentration is exceeded AT ANY TIME, all persons in the fumigation area must wear an NIOSH/MSHA self-contained breathing apparatus (SCBA) or combination air-supplied/SCBA respirator. Applicators must not be exposed to hydrogen phosphide levels above 0.3 ppm as an 8-hour Time Weighted Average (TWA) during application. With exposure up to 1 5 ppm. or TO ESCAPE FROM levels up to 1500 ppm, an NIOSH/MSHA approved full face gas mask, hydrogen phosphide canister combination may be used. Above 1 5 ppm, or if concentrations are unknown, an NIOSH/MSHA approved SCBA must be used.

Respiratory protection must be available at the site of application in case it is needed when applying aluminum phosphide within a structure; it does not have to be available for outdoor applications. At any time other than during application the allowable limit for hydrogen phosphide exposure is a ceiling of 0.3 ppm. No respiratory protection is necessary if the chloropicrin concentration, as measured by a Matheson-Kitagawa detection device, does not exceed 0.1 ppm at any time during the fumigation. If it does, fumigators must wear an NIOSH/MSHA approved air purifying respirator approved for organic vapors, an SCBA, or a combination air-supplied SCBA/respirator The threshold for sulfuryl fluoride is 5 ppm; persons may be exposed to this level daily for 8 hours without adverse effects. The Short Term Exposure Limit (STEL) is 10 ppm; persons may be exposed to this level continuously for 15 minutes without adverse effects.

Recomeended Exposure of Fumigants to grains.

Phosphine Recomendation

Hazardous Materials Management

The Superfund Amendments and Reauthorization Act of 1986 require communities and states to develop plans for managing hazardous materials that are found in their areas. The Environmental Protection Agency has compiled a list of extremely hazardous materials for which records must be kept by the local Emergency Planning Committee and the state Emergency Response Commission. EPA has also set up Threshold Planning Quantities (TPQ's) and Reportable Quantities (RQ's) for each material on the list. The TPQ is the amount which, if held in storage at a facility, must be reported to the local Emergency Response Commission The RQ is the amount which, if accidentally released into the environment through misapplication or spillage, must be reported to the Commission. Among the hazardous materials on the EPA list are numerous pesticide active ingredients.

Spill & Leak Procedures

Methyl bromide product directions recommend that if a spill or leak occurs, fumigators should evacuate the immediate area of the spill or leak, then use either an NIOSH/MSHA approved SCBA or a combination airsupplied SCBA respirator to go back into the affected area to correct the problem. The spill should be allowedto evaporate and no one should enter the spill area without respiratory protection until the concentration of methyl bromide is less than 5 ppm. Remove leaking containers to an isolated area and cover them with a polyethylene sheeting (tarp) at  east 4 mi thick. Place the edges of the tarp in a trench and seal them with soil, tamped down tight. Contaminated soil, water, and other cleanup debris comprise a toxic/hazardous waste. If the Reportable Quantity of 1,000 pounds of methyl bromide isexceeded, the spill must be reported to the local Emergency Response Commission. A spill of aluminum or magnesium phosphide products may generate high levels of phosphine gas, hence all personnel must wear an SCBA for spill cleanup. DO NOT USE WATER AT ANY TIME to clean up these spills; water speeds up the production of phosphine, which could result in a toxic or fire hazard. The RQ for phosphine is 100 pounds. If aluminum flasks have been damaged enough to leak, temporarily repair them with aluminum tape, or transfer the undamaged product to a sound metal container. If a spill is only a few minutes old. return intact products to the original flasks, or to another sound metal container, stoppered tightly. Remember to properly label the alternate container. If you do not know the age of the spill, or if the product has been contaminated with soil, water, or debris, gather up the spillage and place it in a small open bucket of less than 1 gallon capacity, with no  more than 2 or 3 pounds of spillage per bucket. Carry out wet deactivation on site if feasible; if not, carry spillage in an open vehicle to a suitable area and deactivate it there. Small amounts of spillage (up to 18 pounds of product) may be spread out in an necessary unless the fumigated area is completely locked or enclosed by a locked fence.

Post-Application Operations

1.    Provide watchmen where required and/or necessary.

2.     Allow enough time and use enough fans to ventilate and aerate in accordance with structural limitations.

3.    Turn on all ventilating or aerating fans where appropriate.

4.     Before re-entry, use a suitable gas detector to determine fumigant concentration so that appropriate precautions may betaken. Most fumigants do not provide adequate odor warning.

5.     Check for gas concentrations in areas that aerate slowly.

6.     Remove warning signs when aeration is complete.

7.     Dispose of empty containers and used canisters.

8.     Return unused chemicals in property and clearly labeled containers to storage area.

                     

    

·         A canister gas mask must be worn when the concentration of gas is higher than 0.3 ppm and less than 15 ppm.

Application Procedures Pre-Fumigation & Fumigation Period

1.     Detailed directions for various types of fumigations are given on the recently improved fumigant labels. READ AND FOLLOW THE LABEL DIRECTIONS.

2.     Post areas to be treated immediately before fumigation. Placarding should be bilingual if workers or neighbors do not read English.

3.      Apply fumigant from the outside where appropriate.

4.      Only allow entry into fumigation area in extreme emergencies, and only with mandatory respiratory protection. When fumigating, consider prevailing wind and other factors that may affect the fumigation.

5.      Post warning signs.

6.      The best way to avoid spills and leaks is to use the product strictly according to label Directions.

7.      Provide watchmen where required. This is always part of a successful fumigation. Careful sealing also saves time and material.

Sealing the Building

The fumiganfs ideal properties of penetration and diffusion also make it difficult to confine and for that reason, a good sealing job is necessary. In fact, properly preparing and sealing the structure is the most important of a successful fumigation. Careful sealing also saves time and material. When sealing a building, think in terms of sealing it so tightly that if it were filled with water, none would escape. Because a fumigant is difficult to confine, high winds, increase fumigant loss and cause the fumigant to drift to the leeward side of the building. If fumigation must be done on a windy day, apply more gas on the windward side to minimize the loss and drift and take gas level readings more often. The first step in sealing the building is to dose off all external openings to the building. Seal root ventilators and chimneys by wrapping them with a tarpaulin, or plastic sheet, or by stripping the screened openings with a wide commercial masking tape. Next, close all stairwells and interior doors and replaceany broken panes. Tightly wedge and lock all exterior doors and windows and caulk or tape cracks. Check for cracks in the floor, roof, and around the eaves and seal them. Take special care to seal partitions to adjacent storage or work areas in a building. Clear adjoining buildings sharing a common wall. If a nearby building is occupied, you must check it frequently with a monitoring device during fumigation to ensure the occupants' safety. Check local regulations

for specific requirements. Appearance, economy and ease of cleanup will probably determine your choice of sealing materials. Where time and neatness are factors, masking tapes and commercial caulking compounds will probably justify their extra cost Because fumigant gas can penetrate accumulations of trash and sweepings, necessary cleanups may be postponed until the fumigation is completed. Open all doors and hatches on milling machinery, including elevator boots and repair openings, conveyer lids, settling chamber doors, and dust trunks. This also

applies to reels, purifiers, sifters, shorts and bran dusters, feeder gates on rolls and purifiers as well as other openings to allow the gas to enter the equipment Be sure to open "dead" spouts before fumigation because they are particularly difficult to penetrate.

Tarpaulin Fumigation

When fumigating packaged commodities, follow the steps listed below:

The Stack

Stacks of stored commodities usually can be fumigated where they stand as long as the

tarpaulin is large enough to cover the stack completely. If, however, material is being stacked expressly for fumigation (such as when unloading a freight car), stack it in a square five or six feet high. Be sure to allow for a tarpaulin margin of at least two feet around the stack when the cover is laid over it. The stack should be on a concrete floor or other airtight surface. Where floors are not airtight (such as on a loading dock), cracks should be caulked or otherwise sealed to prevent the fumiganfs escape. Polyethylen, or additional tarpaulin laid on the floor under the material to be fumigated, can provide a satisfactory seal.

The Gas Expansion Dome Center

Four or more sacks, cartons, or cases upright on top of the stacked material to form a gas expansion dome. The expansion dome aids gas distribution for some fumigants. It is not required, however, for a solid fumigant, such as magnesium or aluminum phosphide, which produces phosphine.

Tubing and Evaporating Pans

 Use copper or polyethylene tubing to inject the gas near the center of the expansion dome. Fasten the outlet of this tubing to an evaporating pan to prevent liquid fumigant from dripping on the commodity being fumigated, or splashing onto the tarpaulin.

The Tarpaulin

Use polyethylene or gas proof, impregnated, tarpaulins. Water-proofed canvas tarpaulins are not satisfactory. Before spreading the tarpaulin, sweep around the stack to provide a clean surface for sealing. Unroll or unfold the tarpaulin over the stack, providing a margin on the floor of two or three feet. Run the applicator tubing out from under the  tarpaulin at a corner, which should be folded. If phosphine tablets or bags are used, there is no need for any special equipment. The tablets or bags can be put in trays and slid underthe cover. Seal the tarpaulin by

weighting it down with a row of bagged material or sand-filled tubes (Canvas or plastic tubing about four inches in diameter may be used for these "sand or water snakes.")

Applying the Fumigant

Release the required amount of fumigant from outside the stack based on the

cubic measurement of the stack.

Removing the Cover

When fumigation is finished, pull the tarpaulin back only partially and leave it for about 30 minutes. This will allow the fumigated material to air out before the cover is removed completely. After aeration, remove the tarpaulin, carefully fold it, and store it for the next use.

Characteristics of the “Perfect Fumigant”

The perfect fumigant:

1.     Controls the target pests effectively.

2.     Has low toxicity to non-target organisms.

3.     Has low use hazard.

4.     Is noncorrosive, nonflammable, and nonexplosive.

5.     Does not react with fumigated products.

6.     Has no undesirable odor

7.     Vaporizes readily.

8.     Penetrates rapidly to location of target pests.

9.     Has low sorption on wood and other building materials

10.  Has low solubility in liquids.

11.  Can be monitored easily.

12. Can be aerated readily.

13.  Is packaged for convenient storage, transport, and disposal.