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Case study 4: Pesticide spraying

Assessor(s): Manager; health and safety representative; spray operator Hazardous chemical:

Product name: Chlorpyrifos 500 EC

Form: Solvent based concentrate containing 500 grams per litre of Chlorpyrifos in a hydrocarbon solvent

Active ingredient: Chlorpyrifos (an organophosphorus insecticide) Health effects: Nervous system (cholinesterase inhibition)

Major routes of exposure: Inhalation (spray mist and solvent) and skin absorption (Chlorpyrifos is readily absorbed through intact skin). Chlorpyrifos is an insecticide used on vineyards. Sometimes other liquid organophosphates are also used, following the same mixing and spraying techniques. Therefore this assessment would also cover their use.

500ml of the concentrate is poured (decanted) from a 20 litre drum, into a plastic jug.

Before pouring this into the spray tank of a tractor-drawn air blast sprayer, water is added to the tank to dilute the concentrate to a concentration of 0.25 grams per litre

(i.e. 2000 times dilution).

The tractor-drawn air blast sprayer can generate a large quantity of fine spray mist.

Chlorpyrifos is sprayed two to three times a week on several vineyards from about October to February.

One operator, who has completed the Farm Chemical Users Course (FCUC), does all the mixing, spraying and the cleaning up of the equipment used.

Others who may be exposed to some Chlorpyrifos are those involved in thinning, pruning or repairing spray equipment. They are not considered to be at risk (refer to report).

Physicochemical hazards: chemical is a flammable liquid category 4 (flash point 68°C).

APPENDIX K – CASE STUDIES

Job description: TaskRoutesControls already in placeRisk to health? Yes/No/Not sureAction MixingSkinGauntlet rubber gloves, PVC apron, gumboots and face shield worn. Measuring jug is rinsed immediately after use. Tap available for washing.

YesSpills and splashes have occurred. Chlorpyrifos is very toxic. It is handled in concentrated form. The SDS indicates it is easily absorbed through skin. If protective equipment is not worn or properly maintained there would be a serious risk to health.

Consider ways of eliminating or reducing the use of the pesticide. Consider using a less hazardous pesticide. Investigate the use of suitable dispensers to minimise spills. A dispenser would mean that less personal protective equipment would be required.

InhalationMixed in well-ventilated area.NoThe SDS indicates that Chlorpyrifos is not very volatile. The solvent is volatile but mixing only takes a few minutes and is done in a well- ventilated area. IngestionNo eating, drinking or smoking when handling the pesticide. Washing facilities are provided.

NoProcedures followed. Operator has attended training course. Supervision provided. SprayingSkinNo specific controls besides a cotton hat, long sleeve cotton overalls and leather work boots are worn.

YesThe operator may be exposed to spray drift although the pesticide is not as concentrated as when it is mixed. The airblast sprayer can generate a large quantity of fine spray mist.

Consider the use of a tractor cabin to control the risk. If the use of a tractor cabin is not practicable, consider application techniques that reduce spray drift.

InhalationAs above.YesAs above. IngestionNo eating, drinking or smoking when handling the pesticide. Washing facilities provided.

NoProcedures followed. Thinning Pruning Picking

Skin, Inhalation, Ingestion

Recommended re-entry periods are observed. People doing these jobs also know when the vineyard was sprayed and the pesticide used. Jobs on the vineyard are coordinated so that people not involved in spraying are kept well away from the areas where Chlorpyrifos 500 EC is sprayed. These people are told when spraying is being done and where.

NoRefer to “CONTROLS ALREADY IN PLACE”. Note: where re-entry periods are not given, operators doing these jobs do not enter the orchard for at least 24 hours so that the spray mist has settled.

None. Current controls are adequate. Ensure existing controls are maintained.

APPENDIX K – CASE STUDIES

RiskControls already in placePhysicochemical risks? Yes/No/Not sureAction e and Skin, Inhalation, Ingestion

After spraying, the empty tank is rinsed and the nozzles flushed. Where the tank is not empty the remaining contents are disposed of in accordance with label instructions, including use of appropriate PPE. The spray equipment, including the tractor, is also hosed down. This process is repeated for the tank and the nozzles if the equipment is to be repaired or serviced externally.

NoWhere the spray tank is empty following spraying, the pesticide is further diluted during cleaning and the task is such that there is no likelihood of skin contact with the diluted pesticide/rinsing water.

None YesWhere the tank is not empty after spraying, skin contact and inhalation may occur during emptying. Risks are minimised by following label directions and wearing appropriate PPE. age Fire risksStorage and mixing operations involving the flammable concentrate are a dedicated work area away from ignition sources and incompatible materials like oxidisers (hypochlorite bleach). Recommendations in AS 1940: Storage and handling of flammable and combustible liquids have been followed. Workers are provided with training and advised of the fire risks

NoProcedures in place and followed including not smoking in storage and mixing areas or while mixing.

None te pesticides such as Chlorpyrifos, are hazardous chemicals for which health monitoring may be required. , health monitoring is likely to be required for workers spraying and mixing the chemical if adequate controls are wever if adequate controls are in place and there is no risk to health, health monitoring may not be required. ers not applying the insecticide, such as thinners, pruners and pickers, would not need health monitoring provided e-entry periods are observed and spraying is not carried out near them when they are working.

APPENDIX K – CASE STUDIES

THIS CODE PROVIDES PRACTICAL