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An air-assisted electrostatic induction-spray-charging (EISC) system operated at 5.0 m3 min-1 air velocity was used to quantify the effects of applied voltage, spray liquid discharge, and spray liquid types on spray chargeability. A computer based data logger in conjunction with Faradays cage and charge-voltage-converter was the instrumentation system used for the accurate measurement of spray cloud current. Generally, higher applied voltage and lower discharge rate for the tank water sprays produced greater chargeability compared to ground water sprays. Increasing the applied voltage to a critical level of about 3 to 4 kV maximized the spray chargeability of water sprays. The charge-mass-ratio (CMR) of ground water and tank water sprays were maximum at 18.5 mC kg-1 and 7.5 mC kg-1 respectively, at discharge rate of 30 mL min-1. The spray chargeability was less affected by the low volume discharges due to formation of relatively larger spray droplets. Distinct mechanical properties as well as higher electrical properties of ground water may have contributed to better spray chargeability due to relatively smaller droplet formation and higher charge transfer time constant, compared to tank water. Determining the best combination of applied voltage and liquid discharge for a given type of spray liquid would help in reducing potential drift by optimizing spray chargeability. Empirical equations were developed to predict the spray chargeability as a function of applied voltage and spray liquid discharge for both ultra-low and low volume discharge ranges. Efforts have also been made to describe the effects of spray chargeability and its influencing parameters with respect to behavior of spray drift.