Selecting the right chemical spray hose is one of the more important decisions a grower or spray contractor makes. The hose sits between your pump and your nozzles, carries aggressive chemistry under pressure, and lives outdoors in harsh Australian conditions. Get the choice right and it will give years of reliable service. Get it wrong and you risk premature failure, contamination, downtime and — most seriously — operator safety incidents. This guide walks through the key factors to weigh up so you can match the hose to the job.
Why a chemical spray hose is different
A standard garden or water hose is not built to handle the concentrated pesticides, herbicides (weedicides) and surfactants used in modern agriculture. Many of these formulations contain solvents and oils that will attack ordinary PVC over time, causing swelling, cracking, softening or hardening of the hose wall. A purpose-made chemical spray hose is engineered to resist that chemical attack while staying flexible and holding pressure. This is why it pays to specify a hose designed for the application rather than reaching for whatever is on the shelf.
Nitrile and PVC blends
One of the most common and effective constructions for agricultural spraying is a nitrile/PVC blend. Nitrile rubber is well regarded for its resistance to oils and many agricultural chemicals, while PVC contributes durability, flexibility and cost-effectiveness. Blending the two gives a tube that stands up to a broad range of spray formulations without becoming brittle or weeping. When you are looking at hoses, ask what the tube (inner) liner is made from and whether it is suited to the specific chemicals you spray — concentration, temperature and contact time all matter.
Chemical and UV resistance in a chemical spray hose
Chemical compatibility is the first thing to confirm. No single hose material resists every chemical, so the safest approach is to check the compatibility of your tank mix against the hose construction, and to consider the most aggressive product you are likely to run through it. If your operation switches between different actives, choose a hose with broad resistance rather than one optimised for a single chemical.
UV resistance is just as important in Australia. Hoses left coiled on a reel in full sun, or dragged across paddocks day after day, degrade quickly if the cover is not UV-stabilised. A quality agricultural spray hose uses a cover formulated to resist sunlight, abrasion and weathering, which protects the reinforcement and tube underneath and extends the working life of the hose considerably. Abrasion resistance also matters where hoses are dragged over stubble, gravel and fence lines.
Working pressure and the safety factor
Every hose carries a rated working pressure — the maximum continuous pressure it is designed to handle in normal use. Your spray system's pressure, including any spikes from pump pulsation or sudden valve closure, must sit comfortably below that rating. As a rule, choose a hose whose working pressure exceeds your system's operating pressure with margin to spare, rather than running a hose at the very top of its range.
This is where the safety factor comes in. Hoses are typically designed so the burst pressure is several times higher than the rated working pressure — that ratio is the safety factor. It exists to absorb pressure surges, the effects of ageing and wear, and the variability of real-world use. Never treat the burst figure as a working figure. Always size your hose around the rated working pressure and let the safety factor do its job as a buffer, not as headroom you plan to use.
A few practical points on pressure:
- Account for surges. Rapid valve closure and pump pulsation create transient spikes well above your steady-state pressure.
- Mind the temperature. Pressure ratings generally fall as temperature rises, which is worth remembering on hot days or with warm tank mixes.
- Match the fittings. A hose is only as strong as its weakest connection, so pair it with correctly rated, compatible fittings and camlocks and assemble them properly.
Other factors worth checking
Beyond material and pressure, consider the bore size to ensure adequate flow to your nozzles, the bend radius if the hose runs around tight reels or implements, and the length and weight an operator will be handling all day. For boom and reel applications, flexibility and kink resistance make a real difference to ease of use and longevity. Choosing a hose that is Australian made and manufactured to relevant Australian and New Zealand Standards gives you added confidence in consistent quality.
Getting the specification right
If you are unsure which construction suits your chemicals, pressures and reeling setup, it is always worth talking it through before you buy. RX Rims has been manufacturing hoses in Brisbane since 1969, and we can help you match a chemical spray hose to your operation. You can browse our product range, and if you have a non-standard requirement — a particular length, bore, fitting configuration or branding — our team can assist with custom hose enquiries. To learn more about who we are, see about RX Rims.
Ready to specify the right hose for your spraying operation? Request a quote or contact us and we will help you choose a chemical spray hose built for the job and for Australian conditions.