pesticide application equipment

Pesticide Application Equipment and Safety

Prepared by Aggrey [email protected] , +256-779864929

mailto:[email protected]

Pesticide application equipment (examples)

lever-operated sprayers compression sprayers

Equipment examples….

Motorised sprayer Handheld sprayer

Lever-operated knapsack (LK)sprayer

WHAT SHOULD WE CONSIDER WHEN BUYING AN LK SPRAYER?

BUYING LK knapsack sprayer

Handle for carrying

Easy re-fit of straps

Non-absorbent material

Grip for final adjustment of straps


Air vent lid

-Possible to shift lever to other side of tank-Access to shift broken diaphragm-Drainage holes in base


Strainer for filling -IN-line strainer -Easy access for strainer cleaning


Possible to set for high or low maximum Pressure / pressure relief valve

Standard cone nozzle and seal – plus different nozzle types

Wide range of nozzles can be fitted in nozzle holder


Possible to lock in off (and on) position

In line strainer – fixed to hose


Possible to read tank contents?


Easy splash-free water filling Leaking from lid and pump !

Operator Safety and Environmental requirements

(what do international standards say?)

Examples of safety hazards for knapsack sprayers• Getting fingers caught between lever and

frame• Cuts from sprayer parts• Strain by heavy lift• Injury by bursting parts• Dermal contact, oral intake and inhalation of

spray droplets or vapour• Tenseness, bad posture, premature tiredness

Sources of environmental hazards for knapsack sprayers• Leakages• Controls• Filling and emptying• Application rates• Distribution, deposition and drift• Loss during stoppage• Cleaning

ISO 19932 (2013) Safety and Environmental requirements• GENERAL - all functions possible for operator wearing

protective gloves- not heavier than 25 kg- materials chemical resistant- avoid outside accumulation of liquid (max. 70 ml)- resistant to twice the maximum working pressure- no leakage

ISO 19932 requirements….

• HARNESS- adjustable- quick release (double shoulder)- non absorbent material- shoulder straps at least 25 mm or 50

mm (>10 kg) wide -Waist strap

ISO 19932 requirements….• SPRAY TANK

- contents gauge accuracy- material UV light resistant- filling opening at least 100 mm wide - nominal volume to be filled in within 60 s- complete drainage (50 ml)

• CONTROLS- quick acting shut-off device (no unintentional

opening, easy to unlock)- pressure regulator (adjustable or changeable)

ISO 19932 requirements….•HOSES

- at least 1200 mm long- no sharp bends

•FILTERS- filling filter with 0.5 to 2 mm mesh width- easy to be changed and cleaned

•SPRAY LANCE AND NOZZLES- spray lance at least 500 mm long - possible to mount standard nozzles- nozzle flow rate must not deviate by more than

10% from specification

ISO 19932 test methods• Functional tests

- shut-off device reliability- spray liquid output- strap drop test- inclination test- contents gauge accuracy and total volume test- filling test- emptying test- absorbency test for straps- chemical resistance of materials- technical residue test- external deposit volume test- drop test

• Pressure test

• Leakage test

• Center of gravity

Strap test failures

Broken hooks

Broken fixing point

Personal Protective Equipment (PPE) use in pesticide application

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!!!!!

!!!

Protective suit contamination after using LK sprayer (source: King and Dobson, 1992)

NOZZLES

Herbicides

ReflexHollow coneFlat fan

Fungicides, Insecticides

Nozzle choice

Types Pressure Spray Advantages(bar) quality

Reflex 1 Coarse Wide angle / less driftHollow cone 3 Fine Good coverageFlat fan: Even spray 2 Medium / Coarse Narrow angle

Nozzle types

CALIBRATION

What is calibration?

• Calibration means testing your spraying equipment with water and measuring how much it can apply on a given area when walking at a given speed using a given pressure and keeping the nozzle at a given height, so that one is able to know;

How much water he/she will needHow much chemical will be neededHow many sprayer full tanks will be neededHow much chemical to add per full tank

How is calibration done?

• Method 1: Tank method

• Method 2: Kalibottle method

CALIBRATING LK knapsack sprayer

Tank method

Add clean water up to a recognizable mark


Tank method

20 m5 m

Spray a given measured area


Tank methodAfter spraying the given area;

Fill measuring jug to top mark

Add water till you reach same content as before spraying

How much water have you used for refill ?


Tank method

Therefore l used for spraying 100 sqm x 100 = l/ha

Calculate l/ha based on the amount of water used for example100 m2:


Finding the chemical dose rate with the Syngenta wheel:

A: calibrated l/ha to be aligned with B: kg or l/ha chemical dose rate

Find C: sprayer capacity

Read D: chemical dose to be added per tank full

A

B

C

D


Using formulas to find out how much chemical to add per tank full:

Pesticide dose rate (ml) = ml / tank Tanks / hectare

Calibrated l/ha = Tanks / hectareL / tank full


Kalibottle method

1. Use a clean sprayer with clean water

2. Check sprayer works correctly and safely

3. With correct nozzle height, measure swath width

4. Practise spraying at comfortable working speed and with correct nozzle height

5. Attach Kalibottle and hold vertical

6. Spray 25 square metre

7. Read off volume rate


KALIBOTTLE method

CALIBRATING LK knapsack sprayerKALIBOTTLE method

Walking – “spraying” 25 sqm

Reading “l/ha”

Repeat to be sure “

In summary (kalibottle method)1. Fill the knapsack spray tank to maximum rated capacity with clean

water.2. Set the correct operating pressure.3. Spray holding the nozzle at the required height and measure the

swath width.4. Using the calibration chart find out how far you must walk to cover

25 or100m2

Most nozzles have an optimum height of 50cms above the first intercepting surface

……..

5. Measure out the required distance to enable you to spray 25 or100m2 (this should preferably be done in the intended spray area to provide a reliable walking speed).

6. Prime the sprayer and fill the tank to the maximum rated graduation line or if there is no line fill to the top.

7. Walking at an even speed spray the 25 or100m2, recording the amount of time taken to complete the task (if you spray more than one row do not record the time taken turning at the end of each row).

8. Refill the sprayer to the same level as in step 6 recording the amount of water required.

9. Using the calibration chart find out the application volume per ha.10. Record all the results on the calibration form.11. Repeat steps 7 to 10 three times to ensure accuracy.

ENDAggrey Atuhaire

Agric. CoordinatorPHE Uganda Project/UNACOH

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