The handling and application of pesticides is well regulated through legislation. The SOPs are developed for legal compliance as a minimum standard while reducing the risk of environmental contamination and exposure to those working with the pesticides. These SOPs are also developed to ensure users get the maximum efficacy from their equipment and pesticides used, so there is no unnecessary re-application required due to over- or under-application.
- Pre-application preparation - notification of intention to spray
The following stakeholder groups need to be notified in advance of planned spraying applications.
- Relevant government departments
- Workers, including contractors
- Neighbours
The pest control operator must issue a pre-treatment notice before applying any agricultural remedies, which must contain all of the following information:
- A description of the areas to be treated;
- Name of the targeted pest;
- Name of the agricultural remedies to be used, their active ingredient(s) and registration numbers;
- Proposed date and start time, and proposed duration of the agricultural remedies use;
- Name and registration number of the pest control operator and his/her contact details at which the pest control operator can be reached for more information about the proposed agricultural remedies use;
- The hazards associated with agricultural remedies intended to be used;
- Precautions that should be taken to minimise exposure to agricultural remedies or its residues.
A pre-treatment notice must be given to the occupants adjacent (within 5km radius) to the area to be treated such as schools, other public areas and residential areas. The notice must:
- Be in type or letters that are clearly legible to a person approaching the treatment area;
- Contain a cautionary symbol (such as a stop sign or raised hand) that will draw the attention of a person approaching the treatment area;
- Display, in bold block letters, the words “NOTICE OF AGRICULTURAL REMEDIES USE”.
- Be visibly posted at normal points of worker entry in to the area.
Warning signs are visibly posted at normal points of worker entry to the area to be treated.
Pre-application preparation – calibration of equipmentAll equipment must be correctly calibrated before the operation to ensure that the correct application rates are applied.
Pre-application preparation – spray mixingPre-application preparation – spray mixing
When mixing label guidelines should always be consulted and followed. All equipment used needs to be triple rinsed and all equipment and stock must be inspected daily for leaks.
Amount needed: before mixing the application the exact amount needed for one single application needs to be carefully calculated, to ensure pesticide wastage is kept to a minimum. This can be determined by knowing the area being sprayed and the application rate as per the label. Mixed chemicals should never be left overnight.
Where to mix: mixing should only occur in restricted, demarcated areas, and should also be conducted away from water courses. Mixing should be done over drip trays.
Mixing process: caution should be applied at all times.
Liquids: fill the applicator 80% full with water before adding the pesticide and topping up.
Wettable powders: pre-mix powder by apply small volumes of water to make a slurry. Fill the applicator halfway, before adding the slurry and topping up.
Mixing pesticides: fo NOT mix concentrates before pouring into the applicator.
Continual mixing: certain applicators need to be agitated during the mixing and application process
Spills: Refer to SOP spills
Please note: Spillage caught in drip trays must be added back into the mixing solution.
ApplicationsThe rate applied should meet:
- The registered rate
- The control objectives
- Label specifications
Applications - techniquesEquipment & personal protective equipment (PPE)
Equipment must be maintained in good working order; and without leaks or other hazards to the operator. The type of equipment used must be suited to the pesticide to be used and must be able to accurately deliver the prescribed application rate. The appropriate PPE must also be selected and worn.
All employees must be properly trained in the use of pesticides and the relevant equipment being used. The correct protective equipment, in good order, shall be provided to employees, as specified on the pesticide label.
Manual vs mechanical
Spray choices must always be in accordance to the label. They should be selected based on best techniques and minimising spray drift.
Manual ground sprays
This is the most widely used application system in forestry due to the nature of the terrain and accessibility. Techniques include foliar, basal stem, spot and cut surface treatments and soil drenching for the control of soil born pests.
Equipment used:
- Knapsack sprayers
- Rickshaws
- Wind boxes
- Brush and wipers
- Ultra- low volume applicators
Refer to SOP knapsack application
Mechanical ground sprays
Terrain permitting this can be used extensively. However, consideration needs to be given to the damage caused by compaction and/or erosion.
Equipment used:
- Tractor-mounted boom spray
- Tractor-mounted sledge
- Tractor-drawn disc
Refer to SOP mechanical application
Aerial sprays
Provides the most extensive reach and is particularly useful when large areas need an application administered in a short window of time. Spray drift is a big issue and needs to be carefully managed and minimised. Ensure that the product is registered for aerial application.
Applications – avoidance of pesticide driftPesticide drift needs to be avoided at all costs as it has the potential to cause extensive damage to non-target organisms.
There are two forms of spray drift that normally occur:
- Vapour drift: air-borne movement of evaporated pesticides. The inherent properties of a pesticide will determine the risk posed by vapour drift and additives can be used to reduce this.
- Spray drift: air-borne movement of the pesticide in its liquid form.
Applications – factors impacting pesticide driftUsually caused by droplets that are too small, therefore it is crucial to ensure spray applicators are fitted with the correct sized nozzles.
Droplet size is classified as follows:
Classification
Droplet diameter (microns)
Aerosol
<50
Mist
51-100
Fine Spray
101-200
Medium Spray
201-400
Coarse Spray
400
Spray drift occurs when the pressure setting is too high and thus results in smaller droplet size.
Adverse climatic conditions
Wind, temperature and relative humidity all influence spray (and volatile) drift. The addition of anti-drift agents and ensuring the nozzle size and pressure settings are correct will all reduce the impact of adverse climatic conditions, but ultimately spraying must be suspended if conditions are not acceptable. The pesticide label will contain guidelines regarding the appropriate wind speeds that need to be followed.
Post-application restrictions – re-entry, harvesting and grazingNo re-entry, harvesting or grazing is permitted immediately after a pesticide application, this can only commence once the withholding period specified on the pesticide label has elapsed.
click here to download SOP Handling infographic
- Why choose a knapsack sprayer
The main reasons for using a knapsack sprayer include:
Terrain: Ideal for land that is too steep, narrow, wet or hard to reach with larger, heavier, ground-driven sprayers. As long as a person can access it on foot, it can be sprayed with a knapsack.
Accessories: A range of tools is available, increasing the scope of applications and making knapsacks both versatile and useful as well as contributing to improving spraying efficiency.
Cost: Knapsack sprayers are less expensive and have lower maintenance costs than ground-driven sprayers.
Convenience: Particularly when it comes to treating relatively small areas.
Pre-application equipment checks1) SICKNESS – Report to supervisor if you are feeling ill.
2) EMERGENCY CLEAN UP KIT – Ensure there is one on site in case of spills, this should normally comprise the following:
- Strong plastic bag with label
- Designated spills kit
- Broom
- Small shovel
- Rubber gloves
3) CALIBRATION – Calibration is the preparation and operation of a knapsack sprayer in such a way so as to ensure that the correct amount of pesticide and spray mixture is evenly distributed over the given area to be sprayed.
Ultimately, calibrating a knapsack enables you to know the volume applied, which is essential when calculating the pesticide volume required.
To determine the chemical volume, you need to know:
- 1) The amount of water being delivered by the equipment
- 2) The pesticide’s properties.
To determine that amount of water being delivered, the knapsack needs to be calibrated. Calibration should happen at the beginning of every spraying season, as well as:
- When any changes are made to the machinery (knapsack) being used, including changing nozzle heads.
- If walking speed is altered when the spray team move to a new compartment.
- If walking speed is altered when there is a change in the terrain within a compartment.
To calibrate the knapsack sprayer, you need to determine:
- 1) Walking speed
- 2) Nozzle output
- 3) Nozzle spray width, determined by nozzle selection and height of the nozzle from the ground.
Using these you can then work out the volume applied and from this calculate the amount of pesticide needed in the tank.
Walking speed
- 1) Measure a calibration distance, we suggest a minimum distance of 50m in the compartment about to be sprayed.
- 2) Fill the tank to the level about to be used (16 – 20L).
- 3) Time how long it takes to walk the distance while pumping at a constant rate.
- 4) Repeat three times and take an average.
- 5) Ensure the person used for the calibration is a representative sample of the team.
Nozzle output
- 1) Using the same pumping rate and therefore pressure as was used in the walking speed test, spray into a container for the equivalent time to walk the calibration distance.
- 2) Measure the water
- 3) Repeat three times and take an average
Nozzle spray width
As previously mentioned, this is determined by the nozzle type used (refer to label) and the height held above the ground. The operators knee height can be used as a guide, (i.e. keeping the nozzle at the operator’s knee height as they spray). This will ensure the swath remains fairly constant.
Volume applied
Pesticide volume required
4) CONTROL CHECKS – Done before every spray.
- Check that it is empty, there are no obvious breaks in the pipes or the tank and that the straps are secure.
- Add some water and check for leaks.
- Pump to operating pressure and again ensure there are no leaks
5) WELL-BEING – Ensure sprayers adhere to the following:
- Have an adequate supply of drinking water to avoid dehydration.
- Do not eat, smoke or drink while handling, working with or apply pesticides.
Application spray settings1) NOZZLE SELECTION – There are three kinds of nozzles:
- Cone nozzles – produce a fine spray and are good for applying insecticides and fungicides to the leaves of plants. WARNING: The slightest breeze will result in spray drift of the fine spray – cone nozzles should NEVER be used for herbicide application.
- Fan nozzles – produce an even spray distribution suitable for herbicide, insecticide and fungicide applications. Flat fan nozzles are good for band application of herbicides while regular fans are for all-over coverage.
- Flood jet (flat fan or defector) nozzles – are often recommended for herbicide applications as they operate well under low pressure and produce an even distribution of spray over an equal swath width on either side of the lance. They are available to spray 0.75m, 1.0m. 1.5m and 2.5m wide depending on the user’s requirement. ALWAYS read the label of the pesticide to ensure the correct spray nozzle has been selected for application.
2) PRODUCTION RATE – Is dependent on walking speed, nozzle selection, nozzle height and type of terrain and vegetation, if any.
3) WATER VOLUME – Make sure the equipment is filled with the right amount of water needed for the concentrated pesticide. The prescribed dilution rates will be stated on the label in litres, normally litres per hectare (l/ha).
Application spray technique1) PPE – Minimum PPE listed below is required at ALL times when spraying. Check the pesticide label to see whether additional PPE is required.
- Two-piece conti suit or overall
- Gumboots/boots (steel toe-capped)
- PVC gloves
- Sun hat
2) SPRAY PLAN – Is required to ensure all areas are covered effectively, efficiently and only once. It will also reduce the risk of workers walking through sprayed areas. Erect no entry signs to inform others of recently sprayed areas and the time when it is safe to re-enter.
3) SPEED / HEIGHT / PRESSURE – When applying pesticides:
- Workers should move forward at a STEADY pace, ensuring the spray nozzle is kept at an EVEN spraying height.
- Nozzle should be 50cm above ground height unless advised.
- Operators need to spray upwind of the area just treated such that the wind blows drift away from the operator. DO NOT allow spray drift to be a risk to downwind bystanders, crops, and/or animals.
Do not spray when:
- Target vegetation is wet or it is about to rain;
- In high wind speeds;
- If the ambient temperatures exceed the range stated on the label or by the spray equipment manufacturer.
4) SPOT APPLICATIONS vs SWINGING – Spot applications procedures should be followed for herbicides, with the spray nozzle in front of the applicator and NO swinging. For pesticide applications, swinging of the spray nozzle is acceptable as long as it is done in a regular pattern.
Post-application cleaningSpecial caution needs to be taken to ensure drinking water is not contaminated.
1) DISPOSAL OF SURPLUS & CONTAINERS – refer to SOP Disposal
2) RINSING OF KNAPSACK TANK – refer to SOP Disposal. When cleaning the filters, it is important to ALWAYS use clean water and to clean the sprayer after every use. Sprayers should NEVER be stored with pesticides still inside, as parts will become corroded and the spray will not operate properly.
3) PPE CLEANING – The washing of shirts and trousers should be done at a designated laundry facility and separately from other clothing. Boots, gloves and other PPE equipment should be washed inside and out and be fully air dried.
4) PERSONAL HYGIENE – Wash hands and face properly before any food or drink is consumed. Bodies should be washed from the top down to ensure contamination doesn’t occur during the washing process.
5) EQUIPMENT MAINTENANCE – As described by the manufacturer. If servicing is required, ensure that this is done within the allotted time frame.
6) STORAGE – Equipment needs to be stored safely, away from children and animals. It should not be stored in direct sunlight and must protected from frost.
click here to download SOP Knapsack infographic
- Hazard ratings
All pesticides are given hazard ratings are based on their LD50 for a rat, administered both orally and through the skin.
LD50 for the rat (mg/g body mass)
Oral
Liquid
Solid
Liquid
Solid
Liquid
Hazard Statement
Colour Bands
Extreme Hazardous < 5
< 20
< 10
< 40
Very Toxic
Red
Highly Hazardous 5-50
20-200
10-100
40-400
Toxic
Red
Moderately Hazardous 50-500
200-2000
100-1000
400-4000
Harmful
Yellow
Slightly Hazardous >500
>2000
>1000
>4000
Caution
Blue
Acutely Hazardous >2000
>3000
Green
As an industry, we endeavour to use only BLUE and GREEN label products. There are, however, incidences where YELLOW or RED label products are used. In the case of alpha-cypermethrin, cypermethrin, and deltamethrin, which are all YELLOW label products, certain companies have permission from FSC (a derogation) to use these products under very strict conditions. Paraquat is another exception which has either a YELLOW or RED label, depending on its formulation, where again certain companies have permission from FSC to use this under very strict conditions.
Local legislation governing spillsLocal legislation driven by international conventions, governs how storeroom and field spills are dealt with.
These local legislations include:
- Disaster Management Act (No. 57 of 2002)
- Fertiliser, Farm Feeds, Agricultural Remedies & Stock Remedies Act (No. 36 of 1947)
- Occupational Health & Safety Act (No. 85 of 1993)
- National Environmental Management Act (No. 107 of 1998)
- NEM: Biodiversity Act (No. 10 of 2004)
- NEM: Waste Act (No. 59 of 2008)
- Water Act (No. 3 of 1998)
What constitutes a disaster spill?An incident that has the ability to pollute, based on the concentration, sensitivity of the environment, and hazard value of the pollutant concerned:
- Any natural resource such as soil, water and air;
- Cannot be stopped from spreading within an hour;
- Causes death or disease;
- Damage to property and/or infrastructure;
- Causes significant disruption to the life of a community.
Submitting a spill reportSpills need to be recorded in the spill register for internal reconciling purposes, as per company protocol.
If a spill is ABOVE the ‘Disaster Spill’ threshold it also needs to be reported to the relevant Government Department, authority and/or affected people.
Depending on the nature of the spill these include:
- DEA – Department of Environmental Affairs
- DAFF – Department of Agriculture, Forestry and Fisheries
- DOL - Department of Labour
- SAPS – South African Police Services
- Fire Department
- Relevant catchment area or municipality
- Affected people
Treatment of spillsThe following minimum equipment needs to be available to deal with spills in storage and mixing areas:A suitable container with lid such as a Wheelie-bin filled with absorbent material (this can include absorbent pillows and sausages);
- Adequate quantity of bio-remediation agent;
- Squeegee & poly fibre broom;
- Flat scoop such as a dustpan with stiff poly fibre brush;
- Heavy duty plastic bin liners;
- Appropriate Personal Protective Equipment (PPE) according to the label / MSDS including chemical resistant gum boots and PVC gloves;
- Demarcation tape.
Clean-up Procedures – on solid surface:
- Contain the spill by use of covering with absorbent material (or sausages);
- Work in and gather with the squeegee;
- Scoop into bin liners with dustpan;
- Gather fine sweepings with broom and scoop into bin liner;
- Tie bin liner closed and placed in waste bin;
- Wash floor with standard detergent.
Clean-up Procedures – on solid surface:
- Use bio-remediation agent as per instructions;
- Generally this will entail spreading the agent over the spill, working it into the soil, then left to remediate naturally. Some products require the addition of water.
Disposal of spillage residue material:
- An option is to deliver the filled bin liners to a Hazardous Waste collection point if available;
- Alternatively, a bunded area on an impervious surface may be used for bioremediation. The spillage residue material is spread in the bunded area and treated with a bioremediation agent according to the product instructions;
- Once remediated, the material can be safely disposed of.
click here to download SOP Spills infographic
click here to download SOP PPE infographic
- Pros and cons
PROS
1) COST EFFECTIVE – for large spaces, especially the clearing of compartments after harvesting in preparation for re-planting.
2) TIME EFFECTIVE – by far the quickest way to cover large areas.
CONS
1) SOIL AND WATER CONTAMINATION – aerial spraying poses a greater hazard.
2) HARM TO THE ENVIRONMENT – there is a greater potential for accidental contamination.
3) SPRAY DRIFT – potential for contaminating neighbouring land, crops and conservation areas within the plantation.
As a result, the following restrictions have been put in place by the industry:
NO AERIAL SPRAYING:
1) In compartments adjacent to homesteads, communities, or other types of human dwelling;
2) In compartments immediately adjacent to conservation areas, wetlands, rivers or riparian areas;
3) Of insecticides between January to September when there is a risk of impacting bees.
Regulations governing aerial spraying1) Fertiliser, Farm Feeds, Agricultural Remedies and Stock Remedies Act No. 36 of 1947
2) SANS: 10118 2011 Aerial application of pesticides
3) SANS: 10206 2010 The handling, storing and disposal of pesticides
4) Occupational Health and Safety Act No. 85 of 1993
There are two parties involved with aerial spraying: the CONTRACTOR who undertakes the spraying and the GROWER whose land is being sprayed. Their roles and responsibilities differ.
Pre-applicationCONTRACTOR’S RESPONSIBILITY
1) AIRCRAFT CONDITION AND CREDENTIALS
- Approved by the relevant authority to conduct pest control operations.
- Crop spraying mechanics need to have been designed and installed in accordance with SANS 10118.
- Regularly inspected in accordance with maintained schedules and repairs should be recorded and signed off by a designated inspector.
2) PILOT
- Commercial pilots license issued by relevant authority.
- Holds a current pest control operator’s certificate from the relevant authority.
- Has paperwork confirming routine medical examinations have been passed.
3) AIRCRAFT CALIBRATION
- Application rate needs to be calibrated once a year, unless changes are made to the application instruments; then it needs to be done again.
- Spray distribution pattern also needs to be calibrated once a year, unless changes are made
4) GROUND CREW – Responsible for mixing and loading:
- Pilot must supervise loading and mixing.
- Must ensure the ground crew have the correct PPE.
5) COMMUNICATION SYSTEMS
- Radios for two way communication with ground crew.
6) PILOT’S PPE – Must protect against fire and contamination from pesticides. xxxxx
GROWER’S RESPONSIBILITY
1) CONTRACTORS CREDENTIALS – Contractor meets all the legal requirements:
- Using a registered pilot and aircraft.
- Ensuring contractor has a current pest control operator certificate.
2) ENVIRONMENTAL SCREENING ASSESSMENT – Ensure that this has been done prior to spraying and that it has been reviewed and signed off by an environmental specialist or a representative from the company’s environmental department.
3) PROVISION OF INSTRUCTIONS TO THE CONTRACTOR
- Exact size of the land being treated.
- Susceptibility of neighbouring crops (in a 5km radius of the spray zone).
- The pesticide(s) being applied and the label warnings and recommendation.
4) WEATHER CONDITIONS
- Temperature is below 20oC.
- Humidity is not below 40%.
- No wind.
- Ensure there are no inversion layers present at the time of spraying.
- This needs to be tested on the day using smoke (either aircraft’s smoke machine or ground ‘cold-fire’).
5) PROVISION OF WATER – For mixing pesticides and washing purposes. There must be periodic analysis of pH and hardness.
6) ADHERENCE TO LABEL RECOMMENDATIONS – In particular: warnings, precautions, resistance, use restrictions, directions, limitations.
7) DELIVERY OF PESTICIDES
8) INFORMING NEIGHBOURS AND STAFF – Workers and neighbours need to be warned ahead of time that aerial spraying will commence. This includes:
- Putting up warning signs.
- Halting all pedestrian access.
- Preventing farm animals and unauthorised persons from accessing landing areas, pesticides or the area until after spraying has been conducted and the withholding period is over.
9) CONDUCTING A SITE EVALUATIONS – The grower and pilot contracted must conduct a site evaluation prior to spraying. This should include:
- Observing the terrain, in particular: obstacles like power lines and telephone masts, residences.
- Identifying the weed/pest problem.
- Being made aware of neighbouring communities and neighbouring land within 5km radius of the spray area.
- Being made aware of any protected conservation areas, water sources, wetlands, riparian regions both within the spray area and 5km radius.
Where aircraft are not fitted with GPS ordinance system, the following must be done: flags or markers, inanimate objects, to demarcate corners clearly as well as any NO GO areas.
ApplicationCONTRACTOR’S RESPONSIBILITY
1) EVENNESS, CORRECTNESS AND QUALITY OF THE APPLICATION
2) ACCORDANCE TO LEGISLATION – Aerial application is conducted in such a way it is accordance with national regulations and statutory requirements.
3) LABEL ADHERENCE – In particular to the restrictions and weather conditions stipulated.
4) PILOT’S HEALTH – Spraying should cease immediately if any signs of sickness, ill health or discomfort are felt. The pilot needs to seek immediate medical attention, taking the label with them. This needs to be noted in the crop spraying logbook and reported to the relevant authority.
5) SPRAY DRIFT IS REDUCED – Aircraft is set up in such a way that primary exodrift (spray drift onto any non-target object) is avoided. This includes ensuring the following are correctly set:
- Nozzle size and position.
- Flying height.
- Wind speed and direction.
- Turbulence and thermal currents.
- Humidity and temperature.
GROWER’S RESPONSIBILITY
1) OBSERVERS – With the company/owner’s permission they may be in a safe area, upwind of spraying and should avoid walking through freshly sprayed compartments.
2) PPE – Observers need to be issued with the correct PPE. There should be spares that are readily available in case contamination occurs.
3) FIRST AID KITS – Need to be maintained and available during spraying, administrated by a trained first aider.
4) NO EATING, SMOKING, DRINKING OR TOILET BREAKS – In the operation area; only in demarcated area.
5) CORRECT WASHING PROCEDURE – Before eating, drinking, toilet breaks or changing, gloves need to be rinsed with water (ideally running) and soap. Gloves can then be removed from hands; face to be washed.
Post-applicationCONTRACTOR’S RESPONSIBILITY
1) REMOVAL OF SURPLUS PESTICIDE – Needs to be done following disposal guidelines (see SOP Disposal), contractor policy and in accordance to SANS 10206.
2) PPE – Pilots and ground crew needs to be cleaned and stored.
3) COCKPIT AND CABIN – Need to be thoroughly cleaned.
4) CHEMICAL LOGBOOK – Needs to be completed and signed by grower representative; a copy to accompany the invoice.
GROWER’S RESPONSIBILITY
1) LANDING STRIP – Needs to be made available, either on the land when the pesticide is being applied or a suitable alternative location that the grower has access and permission to use.
- The landing strip must have suitable drainage facilities for tanks to be emptied and rinsed.
2) PPE – Needs to be cleaned in accordance to grower policy and OHS Act. There must be a process in place to ensure used and clean PPE are kept separate at all times to prevent contamination.
3) REMOVAL OF PESTICIDE CONTAINERS – Refer to SOP Disposal.
4) SIGNING OF CHEMICAL SPRAY LOGBOOK
5) WITHHOLDING PERIOD – No access to the sprayed area is allowed during this time.
click here to download SOP Aerial Spraying infographic as a .pdf
- Pros and cons
Tractor drawn mechanical, and semi-mechanical, spraying operations comprise various tank configurations attached to the 3-point linkage of an agricultural tractor. The pump, preferably hydraulic, is positioned below the tank containing the pesticide to be sprayed. The spraying operation is activated by engaging the tractor hydraulic, or PTO drive system (with shaft correctly shrouded) and then activating the desired valves. The valve bank needs to be easily and ergonomically accessible to the tractor driver. The pesticide is pumped through appropriate piping along the boom of the tractor, to either nozzles (attached to the boom) or drop down hoses with attached lances and nozzles, which release the pesticide onto the target vegetation or pests.
PROS
1) TIME – allows you to cover a far greater area in a set time frame.
2) ERGONOMICS – reduce the strain being placed on the workers, as they do not need to physically carry the knapsack with the pesticide being applied.
3) EFFICIENCY – a more uniform result improving the efficacy of the pesticide.
CONS
1) SLOPE – incline/decline limitations of both tractors and spray carts.
2) TERRAIN CONDITIONS
- a) Avoid weed/coppice re-growth height over 1.5m – hinders access, negatively affects pesticide effectiveness, can potentially lead to serious pesticide damage to planted trees.
- b) Stumps – hinder access.
- c) Rocky outcrops – damage machinery.
- d) Steep road banks – hinder access.
Uses1) PRE-PLANTING – Herbicide – broadcast spray, controlling all undesirable vegetation.
2) POST-PLANTING – Herbicide – selective systemic – lances attached to tractor boom:
- a) Cloning operations - broadcast spray - targeting all weeds.
- b)Chemical hoe - targeting identified weed species.
Pre-application - Pre-entry risk assessment and spray planSPRAY PLAN
A pre-determined route needs to be designed for the compartments being sprayed. This should take into account:1) Slope: DO NOT WORK ALONG THE CONTOUR.
2) Direction of spray.
3) Areas to be avoided (i.e. water bodies, neighbouring crops and homesteads, conservation areas), or could be negatively affected by spray drift, as well as buffer zones.
Pre-application - Pesticide selectionTIPWG APPROVED LIST PESTICIDE
Ensure the pesticide about to be used is on the list and thus complies with all South African legislation and certification requirements.
LABEL INSTRUCTIONS
Need to be understood and followed at all times. Material Safety Data Sheets (MSDS) need to be available.
Pre-application - Weather conditions1) Wind speed – can cause chemical drift.
2) Ensure the application method is appropriate for the weather conditions:
- a) Open nozzle spraying - no wind.
- b) Coning or enclosed booms - slight wind.
- c) Dribble bar - windier conditions.
3) Rain – Know the rain-fastness of the pesticide being used.
4) If the wind speed changes significantly during spraying, spray operations need to be adjusted accordingly.
Pre-application - Site set-upWATER
Strategically place a bulk water unit for refilling close to the spray site, so to avoid unnecessary delays.
HEALTH AND SAFETY
1) First aider and first aid kit on site.
2) Report sickness.
3) Emergency clean up kit – adhere to the label specifications, if not stated then ensure the following minimum:
- a) Shovel
- b) Heavy duty plastic bag
- c) Sand
- d) Broom
4) Extra PPE available in a demarcated area.
WELL-BEING
Access to clean drinking water. No eating, drinking, toilet breaks or smoking while operating. Ensure hands and face are washed prior to eating, drinking, smoking and toilet breaks.
Pre-application - Tractor set-up1) All machinery needs to be regularly maintained as per manufacturer specifications.
2) Daily check-lists should be completed by appointed operator and signed off by respective manager/forester.
3) All machinery should be inspected prior to spraying, this should include tightening pipes, fittings and nozzles. Additional care needs to be taken to look for leaks.
4) Tanks should be flushed if they are not used for extended periods.
5) Tractors should be fully refuelled prior to spraying.
Pre-application - Nozzle selectionMake sure the nozzle selected delivers the appropriate cover and water volume, refer to label. Ensure the same nozzle type is used across the entire boom.
1) Chemical hoeing – raindrop type nozzles as they have heavy, coarse droplet sizes which reduces spray drift.
2) Coning – flat fan type nozzles as they create good coverage and overlapping.
3) Coppice regrowth – narrow angle full cone nozzle as this supplies good penetration and coverage.
Pre-application - CalibrationNOTE: Spray operations associated with tractor mounted booms that involve spray techniques that do not conform to a consistent swath and speed, (coning / chemical hoeing) are difficult to calibrate. Therefore, a percentage volume, as indicated on the label, should be applied.
1) Fill the tank with clean water.
2) Set pressure to pre-determined pressure for the operation in hand.
3) Measure a calibration distance – a minimum of 100m.
4) Ensure the tractor is geared correctly, so it will work at a constant/acceptable spraying speed (0.5m/second or 1 km/hour). Note the terrain being sprayed will determine the final speed.
5) Record the time it takes to drive one swath of full-cover spraying over the measured distance.
6) Repeat twice more to get an average.
7) Measure the width of the spray pattern over the entire boom. Check individual spray patterns over bare soil to verify an even spray distribution and nozzle overlap.
8) With the tractor stationary, place a suitable sized measuring jug under one of the nozzles and commence spraying for average time recorded above.
9) Measure the collected volume of water. Then repeat the step twice to get an average.
Pre-application - Total volume water require per hectareYou first need to work out the TOTAL VOLUME sprayed during the calibration. This is done by taking the av-erage collected volume of water from a single nozzle and multiplying it by the number of nozzles being used.
You also need to work out the TOTAL AREA sprayed this is simply the calibration distance used multiplied by the spray width measured.
Pre-application - Filling procedureALL PERSONS INVOLVED WITH MIXING MUST WEAR THE CORRECT PPE – refer to label prior to filling. Ensure all the filters/sieves inserted at the nozzle ends are present and clean.
1) Check spray nozzles are firmly attached.
2) Use a flat hose to fill the tank, ensuring the water used is clean and a water filter is in place.
3) Pour in the pre-measured volume of pesticide, as water is being added to the tank. This ensures proper mixing.
4) Ensure any surplus pesticides and empty containers are disposed off accordingly – Refer to SOP Disposal.
ApplicationThe set up procedure for the mechanical spraying is largely determined by whether the spraying operation is a pre or post-plant operation:
PRE-PLANT SPRAYINGSpraying rig enters the compartment, folds out the booms, engages the pump, selects the correct tractor gear (determined in calibration) and commences spraying.
POST-PLANT SPRAYINGSpraying rig enters the compartment, folds out the booms, fits the lances to the boom at the quick coupling points, lifts the boom, engages the pump, selects the correct tractor gear (determined in calibration) and com-mences spraying.
Application - Spraying procedureThe mechanical sprayer must maintain the same speed as was used in the calibration exercise to ensure the correct volume of pesticide is applied. The spray team must follow a clear, pre-determined, spraying plan that ensures no area is sprayed twice or missed.
Application - Spray operators1) Need to be wearing correct PPE according to the pesticide label, refer to SOP PPE.
2) NO person allowed within 20m of operational spray unit unless wearing suitable PPE.
3) Extreme care must be taken not to spray seedlings during post-planting herbicide spraying.
4) Sprayers must be evenly matched in terms of physical ability and walking speed.
5) Sprayers must swop positions periodically during the day to relieve the static nature of holding the pipe for long periods.
6) Be alert to objects and uneven terrain that could hinder spraying operations.
7) Take extra care when working behind booms – uneven terrain can cause them to swing suddenly.
8) Detach the lance at the quick coupling points when turning or travelling.
NOTE: If conditions change (slope, terrain) or machinery changes (tractor, spray cart) the calibration needs to be repeated to ensure accuracy.
Post-application1) PPE to be washed separately.
2) Wash gloved hands before removing gloves and then wash hands and face before eating, drinking, smoking or going to the toilet.
3) Wash body from the top down.
click here to download SOP Mechanical Sprayer infographic as a .pdf
- Four calculations
1) Area to be sprayed
On the label it will have the pesticide rate per hectare. Often, we are applying pesticide to areas that are not clearly defined in hectares, for example fire break strips or irregular shaped compartments. So it is important to work out the hectares to be sprayed.
2) Total amount of the product required
The pesticide application rate can be found on the label.
3) Number of spray tanks required
To work out the spray output you need to CALIBRATE your equipment – refer to SOP Knapsack and SOP Mechanical sprayer
4) Amount of pesticide required per tank
Get mixing – waterFill tanker with ¼ to ¾ water – always adding the pesticide to water and not the other way around.
Keep the water agitated.
Each product must be fully dispersed/solubilised before the next is added.
Get mixing – preparationMix outside or in a well-ventilated area.
If working outside ensure you back is to the wind to prevent fumes and dust being blown towards you.
Pesticide containers should always be placed on a secure, stable surface.
Mix and load pesticide on a concrete slab if possible.
Always use a catch basin when mixing to prevent inadvertent spills.
Measure carefully using clearly labelled ‘PESTICIDE’ measures that are washed separately.
Get mixing – mixNever open pesticide containers higher than chest level or lift open containers over chest height.
Mix at waist level, never at eye-level.
Never stir with hands/arms, always use a clearly labelled ‘PESTICIDE’ stir-stick.
WashingAfter handling pesticides ALWAYS WASH YOUR HANDS
- Wash your gloves before removing them.
- Remove your clothes, place in a bag ready to be washed separately.
- Wash your hands thoroughly.
- Wash your face (and exposed body parts).
click here to download Pesticide Mixing infographic
- Why choose a mist blower
Pros
- Uses a lower volume of water per application - this helps conserve water and saves on water transport costs.
- Misting effect improves the coverage for contact products on target pests.
- Good choice for fungicide and insecticide applications, as well as for pest control in a nursery setting.
Cons
- Can result in over-application of products if the operator is not trained.
- Wind greatly affects applications, due to the fine droplets.
- Not ideal for herbicide applications.
Pre-application1) Sickness – report to supervisor if you are feeling ill. If treatment is sought, ensure the pesticide label is taken along to the medical facility.
2) Emergency clean up kit – ensure there is one on-site in case of spills. This should comprise the following:
- Strong plastic bag with label
- Designated spills kit
- Broom
- Small shovel/spade
- Rubber gloves
3) Control checks – done before every spray.
- All engine components are secure and not damaged
- The on/off switch works
- The throttle control works
- The mist blower nozzle, hoses and connections have no leaks or any other defects
- Gaskets on the tank lid are not leaking
- The harness is in good working order
- The valve on the mist blower does not leak
- The lids on the chemical tank and fuel tank are secured and do not leak
- The anti-vibrations rubbers are not damaged
4) Setting the harness – adjust the harness straps so that the back-plate fits snugly and securely against your back, by adjusting the height and angle of the straps.
5) Checking coverage – use water sensitive paper (WSP) to ensure the correct coverage when applying pesticides with a mist blower.
- Fill mist blower with water.
- Create a diagram of the tree that will be sprayed.
- Clearly mark where WSP will be placed on the tree, ensuring:
- The distribution of the WSP covers areas where pest damage is found and/or in areas where coverage will be difficult to achieve.
- Enough WSP is used to get an accurate depiction of the spray coverage.
- Label WSP in accordance to their position on the tree diagram, then attach using staples or bulldog clips on the corresponding areas of the tree ensuring:
- The sensitive side of the WSP is facing outwards
- There is no dew on the tree, which could activate the WSP and skew the results.
- Start the operation, making sure the operator operates in their normal fashion.
- Collect WSP and check the spray pattern against the diagram below.
- If the WSP is representative of 85 drops per cm2, pesticide application is correct. If not, repeat the steps adjusting how the operator applies the mix.
PLEASE NOTE: WSP is not fool proof and the denseness of the trees foliage can skew the results.
6) Well-being
- Have an adequate supply of drinking water to avoid dehydration.
- Do not eat, smoke, drink or take toilet breaks while handling, working with or applying pesticides.
Application1) Production rate – dependent on walking speed, nozzle height and type of terrain.
2) Water volume & mixing – make sure the equipment is filled with the right amount of water for the concentration of pesticide. The prescribed dilution rates will be stated on the label in litres, as litres per hectare (l/ha). A percentage mixture is often recommended too. Pesticides need to be mixed in accordance with label specifications and percentage application rate.
3) PPE (always refer to the label) – minimum PPE listed below is required at ALL times when spraying. Check the pesticide label to see whether additional PPE is required.
- Safety helmet – if working under a tree canopy
- Eye protection
- Hearing protection
- Gloves/mitts
- Leg protection
- Safety boots
- Mask/respirator – in accordance with the pesticide’s label
4) Carrying or moving with the mist blower – the mist blower should be turned off when being carried for a distance. It should always be worn as a backpack and not over one shoulder. Harness should be correctly fitted.
5) Starting the mist blower
- Place the unit securely on the ground and make sure that bystanders are well clear of the mist blower outlet.
- Make sure you have a firm footing.
- Hold the unit with your left hand on the housing and put one foot against the base plate to prevent it from slipping.
- Pull the starter grip slowly with your right hand until you feel it engage and then give it a strong brisk pull. Do not pull out the starter rope to full length – it may break.
- Do not let the start-grip snap back. Guide it slowly back into the housing so that the starter rope can rewind properly.
If the engine is cold:
- Turn the choke knob to ‘N’ and continue cranking until the engine runs.
If the engine is warm:
- Continue cranking until the engine runs.
- As soon as the engine is running, return engine to idle speed. Operate the throttle trigger; the choke knob will automatically move to the run position.
6) Operating the mist blower
- Mist blowers are designed for single-handed operations. Fingers should wrap tightly around the handle, keeping control of the handle by cradling it between thumb and forefinger.
- Ensure sound footing and stable posture at all times.
- Workers should move forward at a STEADY pace, ensuring the mist blower is kept at an even spray height, trying to keep to the same distribution pattern to ensure even pesticide coverage.
- Operators need to spray upwind of the area just treated such that the wind blows drift away from the operator. DO NOT allow spray drift to be a risk to downwind bystanders, crops, and/or animals.
7) Refuelling – this should be done in an area that has been cleared of debris to prevent accidental fire/spillage. A fire extinguisher must be present when refuelling.
8) Spray plan – this is required to ensure all areas are covered effectively, efficiently and only once. It will also reduce the risk of workers walking through sprayed areas. No entry signs should be erected to inform others of recently sprayed areas; also indicate the time when it is safe to re-enter.
- Plan refuelling so as to avoid walking long distances.
- Ensure sufficient pre-mixed fuel is available for the days production.
9) Spray environment
- Ensure there are no people or animals in the target area.
- Prevent pollution of any water supply, river, dams, ponds etc..
10) Do not spray when
- Target vegetation is wet or it is about to rain.
- In high wind speeds.
- If the ambient temperatures exceed the range stated on the label or by the spray equipment manufacturer.
Post application1) Disposal of surplus containers – refer to SOP Disposal
2) Rinsing of mist blower tank – refer to SOP Disposal. When cleaning the filters, ALWAYS use clean water and clean the mist blower after every use. Mist blowers should NEVER be stored with pesticides still inside, as parts will become corroded and the spray will not operate properly.
3) PPE cleaning – the washing of shirts and trousers should be done at a designated laundry facility and separately from other clothing. Boots, gloves and other PPE equipment should be washed inside and out and be fully air-dried.
4) Personal hygiene – wash hands and face properly before any food or drink is consumed. Bodies should be washed from the top down to ensure contamination doesn’t occur during the washing process.
5) Equipment maintenance – as described by the manufacturer. If servicing is required, ensure that this is done within the allotted time frame.
6) Storage – equipment needs to be stored safely, away from children and animals. It should not be stored in direct sunlight.
click here to download SOP Mist Blower infographic
click here to download SOP read the label infographic