Commercial Dishwashing vs Manual Washing

Both a commercial dishwasher and a correctly run three-sink manual wash can safely clean and sanitise crockery, glassware and utensils — the difference is how they achieve sanitising. Machines use heat (a final rinse commonly around 82°C) or a chemical sanitiser dosed automatically; manual washing relies on very hot water or a measured chemical sanitiser with the correct contact time. Whichever you use, items must be washed, sanitised, then air dried. Always confirm requirements with your state or territory food regulator. Key takeaways: Both methods must clean AND sanitise, then let items air dry — washing removes visible soil, sanitising reduces micro-organisms to a safe level, and air drying avoids recontamination from tea towels.. Commercial dishwashers sanitise either by heat (a final rinse commonly around 82°C) or by an automatically dosed chemical sanitiser; check the machine reaches its target with a temperature gauge, thermolabel or test strips.. Manual washing generally uses a three-step sink method: wash in hot detergent water, rinse, then sanitise either in very hot water (commonly around 77°C or hotter, needing tools to handle it safely) or in a chemical sanitiser at the label concentration and contact time.. Contact time matters — chemical sanitisers only work if items stay wet with sanitiser at the correct strength for the time stated on the label (often around 30 seconds to a couple of minutes, but always as the product specifies).. Never towel-dry sanitised items; let them drain and air dry. Standard 3.2.2 generally requires eating and drinking utensils to be cleaned and sanitised, and equipment kept in a clean, sanitary condition.. What 'clean' and 'sanitise' actually mean Warewashing is two distinct jobs. Cleaning uses detergent and physical action to remove visible food, grease and dirt from a surface. Sanitising is a separate step that reduces the number of micro-organisms left behind to a safe level — it does not work properly on a dirty surface, because food soil shields bacteria and can neutralise chemical sanitiser. That is why every effective method, machine or manual, cleans first and sanitises second. Under Standard 3.2.2 of the Food Standards Code, eating and drinking utensils must generally be cleaned and sanitised, and other food-contact equipment kept clean and in a sanitary condition. The Code's definition of 'sanitise' allows this to be achieved with heat, with a chemical sanitiser, or with a combination of both. Cleaning = removing visible soil and grease with detergent and physical action. Sanitising = reducing surviving micro-organisms to a safe level using heat or chemicals. Sanitiser works poorly on a dirty surface — always clean thoroughly first. Standard 3.2.2 generally requires eating and drinking utensils to be cleaned and sanitised. How commercial dishwashers sanitise Commercial dishwashers — including pass-through and conveyor models — are designed to clean and sanitise in one automated cycle, which makes them fast, consistent and easy to verify: a major advantage in a busy kitchen. There are two broad types. High-temperature machines wash and then deliver a hot final rinse, commonly around 82°C, using heat to sanitise (the wash tank usually runs cooler). Low-temperature (chemical) machines wash at a lower temperature and inject a chemical sanitiser — typically a chlorine-based product — into the final rinse. Follow the manufacturer's specifications for your particular machine, because target wash and rinse temperatures, cycle times and sanitiser dosing vary by model. Whichever type you run, the machine only sanitises reliably if it is dosing correctly, reaching temperature and not overloaded. High-temperature machines sanitise with heat — a hot final rinse commonly around 82°C. Low-temperature machines sanitise by injecting a chemical sanitiser into the final rinse. Scrape and pre-rinse items so the machine is cleaning, not just spreading soil. Load racks so water reaches every surface — don't nest or overcrowd items. Keep detergent and rinse-aid or sanitiser reservoirs topped up and correctly dosed. How to verify a dishwasher is working A machine that looks like it is running is not proof of sanitising. Verify it. For high-temperature machines, confirm the rinse reaches its target temperature using the machine's gauge and, periodically, an independent check such as a probe thermometer, a maximum-registering thermometer, or a heat-sensitive thermolabel run through on a plate. For chemical machines, use the appropriate sanitiser test strips to confirm the rinse delivers the right concentration. Build these checks into your cleaning schedule and record them — an authorised officer will look for evidence your warewashing actually sanitises, not just that a machine is present. Service the machine on schedule and clean its filters, wash arms and jets so spray is not blocked. High-temp machines: confirm final-rinse temperature with the gauge plus periodic independent checks. Chemical machines: confirm sanitiser concentration with the correct test strips. Log the checks as part of your cleaning schedule. Descale, clean filters and clear spray jets so water and heat reach every item. If a machine won't reach temperature or dose correctly, report it and switch to manual washing until it is fixed. The three-sink manual washing method Where there is no machine — or as a backup when the machine is down — manual washing is done properly using a three-compartment (three-sink) approach: wash, rinse, sanitise. A dedicated double or triple sink, separate from the designated hand-wash basin, keeps dirty water, rinse water and sanitiser apart. The first sink holds hot water and detergent for washing; the second holds clean water to rinse off detergent and loosened soil; the third delivers the sanitising step. Scrape and pre-rinse plates first so the wash water stays effective, and change the water regularly once it turns greasy or cool, because tepid, dirty wat