The projection of water spray on to an outdoor risk is most
effective when the spray nozzles are placed as close as possible
to the risk, without risk of damage to the nozzle system by a
fire on the risk. The effect of wind on spray reaching the risk
is also reduced by using nozzles delivering spray uniformly over
the area covered. Nozzles with a hollow spray cover are less
effective than nozzles with a peaked or uniform spray cover.
Excessive wastage of water by projection beyond the risk being
protected may be minimised by using spray nozzles of small cone
angle.