Safer way to spray crops wins award

Rodney Ng with the knapsack sprayer that minimises contact with chemicals. Picture / Dean Purcell

Auckland design engineer Rodney Ng was always wary of his father coming into contact with dangerous chemicals as a market gardener.

The 22-year-old Unitec graduate was cautious when spraying crops in the family garden with "bad chemicals, some of them carcinogenic ... but my dad was very unaware of how dangerous the chemicals were".

The potential threat to his father's health moved Mr Ng to design a unit that would minimise contact with chemicals while spraying.

Mr Ng's invention, the Su Vario (short for spray unit variable), won him the fifth annual Dyson Product Design Award, announced last night at a ceremony in Auckland.

The knapsack unit keeps the main water chamber separate from the chemical, mixing them during, not before, the spraying process. Mr Ng says this reduces contact with a hazardous substance by 90 per cent.

The chemical and spray ratios are more accurate, reducing waste and preventing over-spraying.

Mr Ng's prize includes a trip to Britain with $3000 for expenses.

Other award finalists included Massey University graduates Lydia Smith, who made a powerful and mobile wheelchair, and Rhys Hunt, who designed a device to make shoeing horses easier.