When should you use degreaser versus sanitiser first?

The decision between starting with a degreaser or going straight to a standard detergent depends entirely on the type and severity of contamination on the surface. A degreaser is an alkaline chemical formulated to break down fats, oils, and carbonised food residues that standard neutral detergents cannot shift. If the surface has heavy grease buildup, baked-on deposits, or sticky fat residues, a degreaser must be used as the first stage before rinsing and then applying sanitiser. If the surface has only light contamination such as fresh splashes, crumbs, or thin liquid films, a standard detergent is sufficient for the first stage. In either case, the sanitiser always comes last, after the surface has been cleaned and rinsed.

Common misunderstanding: You should always use a degreaser because it is stronger than a standard detergent.

Degreasers are not simply stronger versions of detergents. They are highly alkaline formulations designed specifically to saponify fats and dissolve carbonised residue. Using a degreaser on surfaces with only light soiling is wasteful, increases chemical exposure for staff, and can damage certain surface materials over time. Standard neutral detergents are more appropriate for light soiling because they remove debris effectively without the corrosive action of high-alkalinity products.

Common misunderstanding: The order does not matter as long as both chemicals are used.

The order is critical. The cleaning chemical, whether a degreaser or standard detergent, must always be applied first to remove visible contamination. Applying sanitiser to a surface before cleaning it will neutralise the sanitiser's active ingredients on contact with the organic matter, wasting the chemical and leaving bacteria alive. The correct sequence is always: clean, rinse, sanitise.

How do you assess whether contamination is heavy or light?

The assessment is made by visual inspection and physical touch before selecting chemicals. Heavy contamination is characterised by visible grease films that reflect light, sticky or tacky surfaces when touched with a gloved hand, carbonised or baked-on deposits that resist a wipe with a damp cloth, and layered residues that have built up over multiple uses. Light contamination presents as fresh spillages, thin liquid films, loose crumbs, or minor splashes where the underlying surface is still visible and smooth to the touch. The distinction matters because it determines which cleaning chemical is needed for the first stage.

Common misunderstanding: Contamination level depends on how long ago the surface was last cleaned.

Time since last cleaning is not a reliable indicator. A surface cleaned two hours ago can have heavy contamination if it was used for frying or roasting in the interim. Equally, a surface that has not been cleaned for several hours may only have light contamination if it was used to hold packaged items. The assessment must be made based on what is actually on the surface at the time of cleaning, not on the elapsed time.

Common misunderstanding: If the surface does not look visibly dirty, it counts as light contamination.

Grease can form a transparent or near-transparent film that is not immediately obvious visually but is detectable by touch. Running a gloved finger across the surface and feeling a slick or tacky residue indicates the presence of a fat layer that requires a degreaser. Relying on visual inspection alone will lead to underestimating contamination and selecting the wrong cleaning chemical for the first stage.

What happens if you use sanitiser on heavy soiling?

When sanitiser is applied directly to a surface with heavy grease or food residue, the active biocidal ingredient, typically a quaternary ammonium compound or sodium hypochlorite, reacts chemically with the organic matter. Fats, proteins, and carbohydrates in the soil consume the active ingredient through a process called organic quenching, reducing the effective concentration below the minimum inhibitory level needed to kill bacteria. The bacteria beneath the layer of soil remain alive and continue to multiply. The surface may smell of sanitiser and appear wet with chemical, but no meaningful reduction in bacterial count has occurred.

Common misunderstanding: Using a higher concentration of sanitiser overcomes the problem of soiling.

Increasing the sanitiser concentration does not solve organic loading. The additional active ingredient is simply consumed by the additional organic matter at the same rate. Manufacturer concentration guidelines are calculated assuming a pre-cleaned surface. Doubling or tripling the concentration on a dirty surface still results in the chemical being neutralised before it reaches the bacteria. It also creates a risk of toxic chemical residues remaining on the surface if it is not properly rinsed afterwards.

Common misunderstanding: Spraying sanitiser and wiping with a cloth achieves both cleaning and disinfecting simultaneously.

This approach fails on two levels. The wiping action may physically remove some surface debris, but the sanitiser's biocidal function has already been compromised by contact with that debris during the spraying and soaking phase. The cloth also picks up the organic matter and redistributes it across the surface as it is wiped, spreading contamination rather than removing it. What remains is a surface that has been partially wiped but not properly cleaned, and partially treated with a chemical that has already been neutralised.