Reducing Spray Drift

The Plant Protection Products (Sustainable Use) Regulations 2012 require that the application of plant protection products (PPP) must be confined to the land, crop, structure, material or other area to be treated. The spray must not drift outside the area of application.

Detailed guidance on applying pesticides is found in the Code of Practice for Using Plant Protection Products (PPP Code).

The Correct Use of Plant Protection Products

Users of PPPs must ensure that all reasonable precautions are taken to prevent spray drift. Reasonable precautions include using the right spraying techniques and equipment, taking account of weather conditions and the need to protect neighbours' interests and other members of the public, wildlife and the environment.

The PPP Code states that the safest conditions in which to spray are when there is a steady force 2 light breeze blowing away from any sensitive areas or neighbours' land. There is a table in the PPP Code which provides a guide to wind speed and when spraying should take place.

Buffer Zones and LERAPs

When spraying near water with certain PPPs, it might be necessary to leave an unsprayed strip of crop at the margin to prevent spray drifting out of the treated area. This unsprayed area is called a buffer zone. The product label (and approval) gives details of buffer zones which must be used. The size of the margin is dependent upon the type of sprayer used, for example, broadcast air-assisted sprayers will require a larger area zone then conventional field crop sprayers.

In certain circumstances it may be possible to reduce the width of the buffer zone by carrying out a Local Environment Risk Assessment For Pesticides or LERAP.

Spray Drift

If PPP spray reaches areas other than the intended crop, it is called spray drift. Users of PPPs must ensure that all reasonable precautions are taken to prevent spray drift. The application of PPPs must be confined to the land, crop, structure, material or other area to be treated.

What causes spray drift?

A combination of factors may affect spray drift including:

wind velocity at spray nozzle height
stability of the local atmospheric conditions
wrong nozzles or pressure choice affecting spray quality
vehicle speed
boom height
poor equipment maintenance
incorrect equipment setting

Spray drift can cause much damage to wildlife and in some cases, spraying may be illegal if the proper procedures for consultation and notification of interested bodies has not taken place. Spray drift is a common result of the misuse of pesticides PPPs and a potential source of friction between farmers and their neighbours.

Therefore, it is essential that the appropriate environmental or conservation agency is contacted before spraying, in case there are particularly susceptible areas that the spray operator is not aware of. See 'The Code of Practice for Using Plant Protection Products' (PPP Code) for further information.

How to Prevent Spray Drift

To avoid spray drift the following must be adhered to:

check the weather forecast before starting off; do not spray if the wind direction and speed would cause spray to drift onto sensitive areas
keep the spray boom as low as possible, consistent with an even spray pattern at the correct target height
check spray angles and adjust height accordingly
use the coarsest appropriate spray quality at all times
when using a boom sprayer, reduce the operating pressure and forward speed but maintain the dose, volume and spray quality within the recommendations on the label
consider not treating the boom or part of the boom closest to the boundary
alternative systems for spray application that are available may help to reduce spray drift when used according to the manufacturer's instructions

Notifying Adjacent Occupiers

Everyone who uses a PPP has a legal responsibility to ensure that all reasonable precautions are taken to protect the health of human beings, creatures and plants, to safeguard the environment and in particular, to avoid pollution of water.

Advice on how users can meet their responsibilities under pesticide legislation is given in the PPP Code which is jointly produced by the Department for Environment, Food and Rural Affairs (Defra) and the Health & Safety Executive (HSE).

The status of the PPP Code as a statutory code of practice is such that whilst it is not in itself an offence not to follow the advice that it gives, failure to do so can be used as evidence of a breach of legislation.

The PPP Code states the following:

'A Control of Substances Hazardous to Health (COSHH) assessment of work with pesticides must take account, so far, as is reasonably practicable, of the way in which exposure could affect members of the public. The COSHH assessment should cover any additional measures required when spraying near premises where there are vulnerable groups of people. Where such people could be affected, the assessment should take into consideration any need to notify or otherwise warn anyone of the work activity.

There are certain occasions when there is a legal obligation to notify others that a spray operation is to take place (eg when aerial spraying). In addition, the conditions of use given in the approval for certain pesticides may contain detailed requirements for the notification of the spray operation and the provision of warning notices.

The application of pesticides by conventional field crop sprayers should not pose significant risk to persons outside the boundary of the field being sprayed, provided that the general advice in the PPP Code is followed by the sprayer. An assessment may conclude that notifying neighbours of spraying will not be necessary for compliance with COSHH. However prior notification of spraying for occupiers of land, premises or houses close to the target area is good practice and may help to allay any concerns there are about possible ill-health effects. Notification may also be desirable where organic or sensitive crops are growing adjacent to the treated area.'

Record keeping

Regarding which PPPs have been sprayed, farmers are required to keep records of which PPPs are applied to their crops and when. To find out which PPPs a neighbouring farmer is using, it may be advisable in the first instance to ask him/her directly. Please note however, that he/she is not legally obliged to show you his/her records.

Reporting Incidents

The HSE is responsible for investigating reports of exposure to PPPs on farms, and for taking action against illegal use.

Any incidents of exposure to PPPs can be reported to HSE on 0845 300 9923.