Dry conditions and low relative humidity are essential, and al warehouses should be serviced to prevent rodent and insect infestation Failure to do this can cause extremely heavy financial losses Pybuthrin is an effective aerial spray to control most flying insects, and this should be used weekly throughout the whole of the factory and warehouses. It is non-toxic but the application should be given whilst the plant is closed down at weekends, as it can have unpleasant effects on personnel whilst the spray is in suspension. The operator should wear a suitable mask whilst using the spraying equipment Rodent control should always be carried out by specialist contractors, as his can rarely be done satisfactorily by factory personnelDry conditions and low relative humidity are essential, and all warehouses should be serviced to prevent rodent and insect infestation. Failure to do this can cause extremely heavy financial losses. Pybuthrin is an effective aerial spray to control most flying insects, and this should be used weekly throughout the whole of the factory and warehouses. It is non-toxic but the application should be given whilst the plant is closed down at weekends, as it can have unpleasant effects on personnel whilst the spray is in suspension. The operator should wear a suitable mask whilst using the spraying equipment. Rodent control should always be carried out by specialist contractors, as this can rarely be done satisfactorily by factory personnel. 232