Farm tests, machine by machine.
We NSTS test fertiliser spreaders, sprayers, slug pelleters and granular applicators, on farms anywhere in the UK. Here’s what each test covers, how often it’s due, and what you get.
Four tests
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Fertiliser spreaders
Machine check, fertiliser analysis and a full-width tray test, with your own fertiliser. Farm-scale twin-disc spreaders and broadcasters, down to the small spreaders used on orchards and greens.
Every year, for farm assuranceRed Tractor, SQC and QMS ask for a yearly calibration with records.1234
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Sprayers
Every application component, with the operator’s and the environment’s safety in mind. Knapsacks, weed wipers and Amistar applicators, up to the widest self-propelled sprayers.
Every year to every 6 yearsBooms over 3 m: every year for Red Tractor Crops and SQC, every 3 years by law. Smaller sprayers: every 6.1254
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Slug pelleters
Machine check, pellet analysis and a spread test, whether you apply pellets with a pelleter, a fertiliser spreader or a spout.
By 5 years old, then every 6Required by law and by farm assurance.61
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Granular applicators
Every application component, then a static output test or a patternation tray test. All types, pneumatic and placement, for any product: most often Nemathorin and Avadex.
Every year to every 6 yearsNematicide applicators every year for Red Tractor and SQC; Avadex and seed treatments every 6.74
Grounds team? See amenity tests. Making or importing a fertiliser, pellet or granule? See trials.
How often each machine is due
The law covers machines that apply pesticides. Fertiliser spreaders are covered by farm assurance instead, unless they put on slug pellets.
The assurance schemes are tighter than the law for big sprayers and some granular applicators.
| Machine | No farm assurance (the law) | Red Tractor: Crops and Fresh Produce | Red Tractor: Beef & Lamb, Dairy, Pigs | Scottish Quality Crops | Quality Meat Scotland |
|---|---|---|---|---|---|
| Fertiliser spreader, fertiliser only | No set frequency8 | Calibrate every year19 | Calibrate every year101112 | Calibrate every year2 | Check every year3 |
| Slug pelleter, or a spreader used for pellets | Every 6 years6 | Every 6 years, calibrate yearly | Every 6 years, calibrate yearly | Every 6 years, calibrate each product | Every 6 years |
| Boom sprayer over 3 m | Every 3 years5 | Every year | Every 3 years (Beef & Lamb) | Every year | Every 3 years |
| Boom sprayer 3 m or less | Every 6 years | Every 6 years | Every 6 years (Beef & Lamb) | Every 6 years | Every 6 years |
| Granular nematicide applicator | Every 6 years | Every year7 | Not listed | Every year | Every 6 years |
| Avadex and powder seed treatment applicators | Every 6 years | Every 6 years | Not listed | Every 6 years | Every 6 years |
The first NSTS test is due before the machine is 5 years old. For assurance, a fertiliser-only spreader needs a yearly calibration with records, not an independent test. Knapsack, handheld and pedestrian equipment has no NSTS test, but must be checked regularly by a competent person, with a record kept.13 Summarised by SCS from the scheme standards, October 2026.4
Questions.
What is NSTS?
The National Sprayer Testing Scheme, run by the Agricultural Engineers Association, which HSE designates to run pesticide equipment inspections in the UK.1415 Besides sprayers and other pesticide kit, it also offers fertiliser spreader testing.16 We wrote the original qualification for fertiliser spreader and slug pelleter testing that NSTS adopted.
Is spreader testing a legal requirement?
How do I check when a machine was last tested?
Enter the test certificate number on the NSTS website’s lookup page. It shows when the test was registered.17
Can you test several machines on one visit?
Tell us everything you’d like tested when you book, and we’ll plan the visit around it. The booking form asks how many of each machine you have.
Book a farm test
Most of our tests happen between January and May, so book a few weeks ahead of your first application.
- Which machines you’d like tested, and how many of each
- The fertiliser or pellets you’ll use, on site on the day
- Your postcode, so we can send the nearest engineer
Or email info@spreadcheck.com. We’ll ring you to fix a date. Nothing is booked until we’ve spoken.
Sources
- Red Tractor, Combinable Crops and Sugar Beet Standards, version 5.1, EC.7 and EC.10, February 2025.
- Scottish Quality Crops, The SQC Standards, 1.11, 2.17 to 2.19, October 2026.
- Quality Meat Scotland, Cattle and Sheep Assurance Scheme Standards, in force from 1 January 2026.
- SCS, Testing requirements by assurance scheme: a summary of the scheme standards (fertiliser spreaders, slug pellets, granular applicators, sprayers), October 2026.
- legislation.gov.uk, The Plant Protection Products (Sustainable Use) Regulations 2012, regulation 11 (boom sprayers over 3 m), 2012, as amended.
- legislation.gov.uk, The Plant Protection Products (Sustainable Use) Regulations 2012 (the UK’s “SUD” rules), regulation 12, 2012.
- NSTS, Granular applicator test requirements, accessed 2026.
- HSE, Guidance on the requirements of the Plant Protection Products (Sustainable Use) Regulations 2012, section 1.10, updated October 2025.
- Red Tractor, Fresh Produce Standards, version 5.1, EC.7, February 2025.
- Red Tractor, Beef and Lamb Standards, EC.10 and guidance, 2025.
- Red Tractor, Dairy Standards, EC.10, 2025.
- Red Tractor, Pig Standards, version 5.1, February 2025.
- NSTS, Sprayer testing leaflet: legal requirements, crop assurance requirements and a decision tree for equipment over 5 years old, 2024.
- HSE, Bodies designated to administer equipment inspection, accessed 2026.
- Agricultural Engineers Association, NSTS, accessed 2026.
- NSTS, About us, accessed 2026.
- NSTS, Look up your test details, accessed 2026.