Take reasonable precautions so that the storage, handling and disposal of products, their remnants (old products and unused tank mixes) and packaging, and the cleaning of equipment, do not endanger human health or the environment. For professional products that means identifying and mitigating the risks and following good filling, storage and disposal practice.
Plan the clean before the spray operation
Before spraying, make arrangements for cleaning the equipment and for disposing of waste pesticide and pesticide packaging (containers, closures and foil seals) safely and legally. When calculating the amount for each load, you can allow for an untreated or under-dosed area for disposing of sprayer washings.
Clean the sprayer inside and out, preferably before leaving the treatment area. After cleaning, store the sprayer under cover. Thorough cleaning to the manufacturer's instructions lowers the risk from handling contaminated surfaces, prevents damage to crops treated later with the same equipment and reduces the risk of blockages.
Agree before spraying who cleans the machine, who receives it afterwards and what information the customer needs. Keep the completed work and supporting records in the contract-sprayer handover, and note cleaning as done only once it has happened. File the cleaning instructions under the machine reference, and review the procedure when a replacement sprayer is used, because its fittings or cleaning system may differ.
Herbicide tank cleaner: read the product's decontamination instructions
Before cleaning, read and follow the label instructions on using appropriate PPE when handling contaminated surfaces and on any decontamination procedure for the product.
Check the label of the actual container rather than carrying over a procedure from a different product: an active ingredient name alone does not describe the whole supplied formulation. If several products were mixed, get the label for each and settle the cleaning question before preparing the next job. If the product's decontamination advice conflicts with the machine's procedure, give both suppliers the exact cleaner, components and instructions concerned and agree the cleaning sequence before the next crop treatment.
Use the machine manufacturer's procedure
When application is finished, clean both the inside and the outside of all equipment you have used, in line with the manufacturer's instructions.
Identify the correct manual for the sprayer and any fitted attachments, and check which fittings and cleaning systems the actual machine has. If the configuration is unfamiliar, ask the equipment supplier rather than assuming a procedure shown for another model applies unchanged; keep the answer with the machine reference.
Include the whole application system
As well as the tank, make sure all pipes, hoses, filters, valves, nozzles and induction systems are thoroughly cleaned. Facilities for washing equipment must be designed so that the pesticide solution cannot get into your washing water under any circumstances.
Add each of these parts to your cleaning checklist, and when you need an engineer's opinion, describe the component and where it sits on the machine, with a photograph filed against that machine. Keep cleaning separate from inspection and repair: a worn fitting, damaged hose or blockage that will not clear needs maintenance, so note the finding and who is dealing with it, while keeping an honest account of the cleaning actually done.
The chemical store must be large enough to hold peak pesticide requirements and any part-used containers, and it needs adequate storage for rinsed empty containers awaiting disposal. Storage for contaminated equipment, personal protective equipment and washing facilities may also be needed; see the store guide.
Plan the amount and destination of washings
Use any built-in rinsing system that is fitted: it cleans the inside of the equipment quickly and effectively with the minimum volume of rinse water. Repeated tank washing, each with a small amount of water, gives better results than a single rinse with a large amount of water and produces less washings.
Before washing starts, decide the route for each stream: equipment washings, unused mixture and empty packaging each need their own collection or permitted-use destination, and the remaining application capacity should be planned so that the washings have somewhere to go.
Distinguish surplus concentrate from cleaning water
Never dilute unwanted concentrate merely to dispose of it as dilute pesticide waste.
First ask your supplier whether they will take back unwanted, unused pesticide. Concentrates are likely to be hazardous waste, so they go through a registered carrier and a licensed waste-disposal contractor. Keep unwanted concentrate in the chemical store so it stays secure and any spill is contained. You or the carrier fill in a consignment note and pay the Environment Agency a fee before hazardous waste moves, and it does not move until the notice period has passed. Producer, carrier and receiver each keep copies of the consignment notes for at least three years.
Label each waste stream with its contents and storage location, and ask the collector how it classifies the actual material and what it needs for acceptance. Describe what you really hold: unopened surplus, part-used concentrate, dilute mixture, collected washings, absorbent material, contaminated components or packaging. If you are unsure what an unlabelled container holds, say so in the enquiry instead of guessing, and do not reuse a waste code from an earlier collection. Ask which extra information the recipient needs and get it from the person who generated the waste.
Keep your spray records in one place. Free to start.
Read container instructions before deciding whether to rinse
The product label states whether you should rinse the container after emptying it. Before disposing of a non-returnable container, make sure it is completely empty. Containers for concentrates applied as a solution should be thoroughly rinsed if you can; containers for ready-to-use formulations or products not applied as a solution are normally not rinsed.
Where rinsings cannot be added to the application equipment, collect them in a suitable labelled container. Store it safely pending the appropriate dilute-waste disposal route.
For returnable packaging, follow the supplier's return arrangements and keep the return instructions with the packaging; do not let a container made for a return system turn into an anonymous storage vessel in the yard.
Rinsable rigid containers and specialist packs
For rigid, non-returnable containers, follow the label's rinsing instructions immediately after emptying and draining. Where instructions are absent, use purpose-made pressure-rinsing equipment or rinse manually at least three times, until visibly clean. Add the rinsings to the spray solution and clean contaminated caps, seals and exterior surfaces.
Paper sacks, cardboard cartons and containers for products applied without dilution are normally emptied completely and kept unrinsed. Never rinse packs for hydrogen cyanide gassing powders or aluminium, magnesium or zinc phosphides: they give off dangerous gases on contact with moisture. Handle and store these empty containers as if they still contained the pesticide and dispose of them through a licensed waste-disposal contractor.
After rinsing suitable rigid packs, replace caps, put the rinsed foil seal inside and store upright in a secure weatherproof place, separated from pesticide stock.
Never reuse empty pesticide containers or contaminated pallets to transport food or animal feed. Send contaminated equipment, unwanted protective clothing and materials from leaks or spills through a licensed waste contractor. Some of these materials require hazardous-waste handling.
Booking the collection and keeping the paperwork
Agree with the collector what it will take, where the waste will be presented and who will be there at the handover. Separate returnable containers, rinsable rigid packs, non-washable packaging and specialist containers before collection, and ask the collector to confirm which of these streams it accepts and how it wants them presented; an answer about clean rigid packs does not cover a specialist container. Match the description, quantity and collection location on the transfer or consignment documents to what is really collected.
After collection, file the documents you actually received, not just the booking confirmation. If the collection differed from the request, note what was taken and what remains, and keep any unresolved stock or waste visible in your working handover until its route is settled. If the sprayer is cleaned by a contractor, give them the product decontamination advice and the machine instructions, and tell them the sprayer, the products used, any residual contents and where waste is stored.
Dilute washings: use or collection
All dilute pesticide waste, including leftover spray and every sprayer washing, must be disposed of safely and legally to protect people, wildlife and the environment, especially groundwater and surface water. For more guidance, contact the Environment Agency or your local authority.
Washings may be applied to the treated or untreated crop within the product's authorisation conditions, including the maximum dose. Alternatively, collect them in a suitable container for a licensed waste-disposal contractor.
A hose-and-brush attachment, available on some sprayers and fitted to others, cleans the outside of the equipment more effectively than a high-pressure spray gun and uses less water.
Other ways to dispose of dilute waste and rinsed containers
When several sites are treated one after another with the same pesticide and equipment, left-over spray from one site can be used on the next if it is transported safely and legally. Disposal of dilute waste onto soil or grass is allowed only under a Groundwater Regulations authorisation issued by the Environment Agency.
Rinsed containers go to a licensed waste-disposal contractor or to a licensed waste-disposal or recovery site that accepts them. Burn them only in an incinerator licensed by your local authority or the Environment Agency.
Reuse an empty container only if it is designed to be returned and refilled and you refill it as the label says.
Cut washings and packaging at source: soluble packs, returnable containers, closed-transfer systems and flushing systems for low-volume sprayers all reduce them.
Granules, dusts and unrinsed packs
Equipment used to apply solid pesticide, such as granules, dusts, pellets and baits, is not usually cleaned with water.
A pack that cannot be rinsed carries the label phrase "Empty container completely and dispose of safely". Handle and store such empty containers as if they still held the pesticide, and pass them to a licensed waste-disposal contractor.
Flexible packaging for solid products applied as a solution may be rinsable, depending on the material and design of the pack. Empty rigid containers into the sprayer first, and let the product drain fully before rinsing.
Waste that leaves the farm also needs a waste transfer note and a written description of the waste.
Leave less to wash and dispose of
Plan the job so little or no spray solution is left over; this reduces disposal problems and saves money. Check stock before ordering, and choose the pack sizes that fit the job. Rounding down the amount calculated at filling leaves room to spray the washings on an under-dosed area, and a suitable electronic sprayer controller gives the same result.
Next step
Keep unwanted concentrate and ready-to-use formulations secure in the chemical store, and find the product's own safety data in the SDS folder.