Foam cleaning protocol for industrial surfaces

Standard procedure for cleaning floors, walls, tables, conveyors and open equipment in the food industry with projected foam: the detergent is applied with projection equipment (cannon, lance or satellite), left to act and rinsed off with pressurised water. Foam covers large surfaces with little product, clings to vertical areas and shows where it has been applied. The doses, temperatures, pH values and times are those given in the technical data sheets of the Instaquim products cited; the pressure and application distance are set by the equipment manufacturer.

Materials required

• Alkaline foaming degreaser: Gras Foam (2-6 % in water at 20-60 °C, pH at 1 % of 12.2 ± 0.5) or, for burnt-on grease, Gras Foam Pro (2-6 % at 20-60 °C, pH at 1 % of 12.5 ± 0.5). Neither may be used on aluminium.
• Chlorinated alternative for heavily greased surfaces with odours: Clor Foam, 5-10 g/l by projection.
• Neutral detergent for delicate surfaces or as a foaming additive: Neutro Foam (1-5 %; as an additive, 0.5-2 %).
• Acid foaming descaler for limescale: Acid Foam or Acid Foam Pro, 2-5 % at 20-60 °C; they do not attack aluminium or stainless steel.
• Enzymatic detergent for biofilm: Enzi Foam (3-6 % at 40-55 °C) or its concentrated version Enzi Foam Pro (1-3 % at 40-55 °C).
• Registered foaming disinfectant, where the hygiene plan requires it: Bacter Clor (chlorinated alkaline, 2-5 %) or Bacter Alcalino (tertiary amines, 1 % or 5 %).
• Foam projection equipment and pressurised water for rinsing; calibrated dosing unit or injector; pH strips or meter
• Personal protective equipment (gloves, goggles, protective clothing) and wet floor signage

Step-by-step procedure

1. Preparing the area and removing gross debris: Remove product and utensils, cover electrical panels and sensors, collect solid debris dry and pre-rinse with pressurised water. Mark off the area and check the materials: if there are aluminium parts, do not use Gras Foam or Gras Foam Pro on them.
2. Choosing the product and dilution: For ordinary grease, Gras Foam at 2 to 6 % depending on the degree of soiling, with water at 20-60 °C; for burnt-on grease, Gras Foam Pro in the same range; where deodorising is also required, Clor Foam by projection at 5-10 g/l; on delicate surfaces, Neutro Foam at 1-5 %. Adjust the injector so that the concentration falls within the range on the data sheet and check it with a pH strip.
3. Priming the equipment and foam test: Adjust the air intake and spray a test area until a homogeneous foam is obtained that clings to the wall without running: too wet and it falls before it acts, too dry and it does not wet the soil. If foam is lacking, Neutro Foam can be added as a foaming additive at 0.5 to 2 %.
4. Applying the foam: Apply from bottom to top on vertical surfaces, with overlapping passes, to control coverage and avoid streaks. Maintain a continuous, visible layer, paying attention to joints, table legs, the underside of machines, wheels and drains. Note the start time.
5. Contact time: Let the foam act for a few minutes without allowing it to dry: dried-on soil re-attaches and forces a repeat. In heat or draughts, work in smaller areas. Scrub only encrusted spots.
6. Rinsing with pressurised water: Rinse from top to bottom until the foam and emulsified soil are completely removed; the data sheets for Clor Foam, Acid Foam and the disinfectants require subsequent rinsing. Check joints and undersides where foam is retained.
7. Disinfection (where the hygiene plan requires it): On the clean, rinsed surface, Bacter Clor is used by projection, immersion or manually at 2-5 % depending on the degree of soiling, at room temperature, allowing 5 to 15 minutes of contact and rinsing with pressurised water; it complies with UNE-EN 13697 at 2 % under dirty conditions against Escherichia coli, Staphylococcus aureus, Enterococcus hirae, Pseudomonas aeruginosa and Listeria monocytogenes, at 3 % against Salmonella, and with UNE-EN 14476 at 2 % against Poliovirus type 1, Adenovirus type 5 and Murine norovirus. Bacter Alcalino, based on tertiary amines, is applied at 1 % (10 g/l) with about 5 minutes of contact for bactericidal effect, or at 5 % (50 g/l) with about 15 minutes for bactericidal and virucidal effect, then rinsed with pressurised water.
8. Periodic stages: limescale and biofilm: Alkaline cleaning and water hardness leave limescale deposits that shelter microorganisms. Schedule an acid clean with Acid Foam or Acid Foam Pro at 2 to 5 % depending on the amount of scale, at 20-60 °C, allowing a few minutes of contact and rinsing with pressurised water; both are applied with foam projection equipment and do not attack aluminium or stainless steel. For the prevention and removal of biofilms, Enzi Foam at 3-6 % or Enzi Foam Pro at 1-3 %, at 40-55 °C, a few minutes of contact and rinsing with water. Always in a cycle separate from degreasing and chlorinated disinfection.
9. Quality control and recording: Inspect under good lighting for the absence of grease, limescale film, foam residue and odours. Record in the log the area, times, product, concentration, contact time and incidents, with the operator's signature.

Verification and control

Verification combines visual inspection with the controls of the HACCP plan. The rinsed surface must be free of grease to the touch, whitish film (a sign of limescale, which justifies the acid stage), foam residue and odours. A pH strip dipped in the rinse water, giving a value similar to that of the mains water, confirms that no detergent residue remains. Where the plan provides for it, ATP checks or microbiological sampling verify the disinfection; a repeated non-conforming result at the same point usually indicates biofilm and justifies the enzymatic cycle. Any deviation (dose out of range, dry foam, incomplete rinsing) is recorded and corrected by repeating the cycle.

Safety and PPE

• Gras Foam, Gras Foam Pro, Clor Foam, Acid Foam, Bacter Clor and Bacter Alcalino carry hazard statement H314 (causes severe skin burns and eye damage): gloves, goggles and protective clothing are mandatory during dilution, application and rinsing.
• In case of insufficient ventilation, the data sheets for Gras Foam, Clor Foam, Bacter Clor and Bacter Alcalino specify wearing respiratory protection; ventilate the room while the foam is being projected.
• Never mix products. Clor Foam and Bacter Clor may release hazardous gases (chlorine) if used together with other products, and Bacter Clor releases toxic gases in contact with acids: the chlorinated and acid stages are always run in separate cycles, with complete rinsing between them.
• In case of contact with the eyes, rinse with water for several minutes, remove contact lenses if easy to do so, continue rinsing and call a poison centre or doctor. Non-slip boots, wet floor signage and the safety data sheet to hand.

Recommended Instaquim products

The Instaquim foaming range covers the four stages of the protocol. Degreasing: Gras Foam (2-6 %) for heavily greased floors, walls and surfaces in the food industry, cutting rooms and meat processing; Gras Foam Pro, with the same range, for burnt-on grease; Clor Foam, with active chlorine, surfactants and chlorine-stable sequestrants, for cleaning, hygiene and deodorising; and Neutro Foam as a neutral detergent or foaming additive. Descaling: Acid Foam and Acid Foam Pro, which do not attack aluminium or stainless steel. Biofilm: Enzi Foam and Enzi Foam Pro, high-foaming enzymatic products. Contact disinfection of surfaces and equipment: Bacter Clor (registration 18-20-06676-HA) and Bacter Alcalino (registration 19-20/90-06281-HA), registered biocides that comply with UNE-EN 13697 and UNE-EN 14476 under dirty conditions. None of these foaming products carries the EU Ecolabel.

Applicable regulations: Regulation (EC) No 852/2004 (food hygiene) and Regulation (EC) No 853/2004 (food of animal origin), which require a HACCP-based cleaning and disinfection plan; Regulation (EU) No 528/2012 on biocidal products, which covers the registration of Bacter Clor and Bacter Alcalino; Regulation (EC) No 648/2004 on detergents; Regulation (EC) No 1272/2008 (CLP); and the standards UNE-EN 13697 and UNE-EN 14476 cited in the disinfectant data sheets.

Frequently asked questions

At what dose is the alkaline degreaser used in the foam?

Gras Foam and Gras Foam Pro are diluted at 2 to 6 % depending on the degree of soiling, at 20-60 °C: the low dose for daily maintenance and the high dose for accumulated grease, reserving Gras Foam Pro for burnt-on grease. Clor Foam is applied by projection at 5-10 g/l.

How long should the foam be left to act?

Detergent foams act for a few minutes, without being allowed to dry. For disinfection the times are fixed: Bacter Clor 5 to 15 minutes; Bacter Alcalino about 5 minutes at 1 % (bactericidal) or about 15 minutes at 5 % (bactericidal and virucidal). Then rinse with pressurised water.

Can alkaline foam be applied to aluminium?

Not with Gras Foam, which is used on all types of metal except aluminium, nor with Gras Foam Pro, which must not be used on aluminium surfaces. For those parts a neutral product such as Neutro Foam is advisable. Acid Foam and Acid Foam Pro do not attack aluminium or stainless steel.

Does the foam clean and disinfect at the same time?

No. Gras Foam, Clor Foam, Neutro Foam, Acid Foam and Enzi Foam are detergents. Disinfection is a subsequent stage, on the clean, rinsed surface, with a registered biocide: Bacter Clor or Bacter Alcalino, which comply with UNE-EN 13697 and UNE-EN 14476 under dirty conditions, followed by rinsing with pressurised water.

When is an acid clean needed?

When white films or limescale deposits appear, caused by water hardness and by the alkaline cleaning itself. It is scheduled as a separate cycle with Acid Foam or Acid Foam Pro at 2 to 5 % depending on the amount of scale, at 20-60 °C, allowing a few minutes of contact and rinsing with pressurised water.

Which product is used against biofilm?

Enzi Foam and Enzi Foam Pro, high-foaming enzymatic detergents for the prevention and removal of biofilms in the food industry: Enzi Foam at 3-6 % and Enzi Foam Pro, concentrated, at 1-3 %, both at 40-55 °C, allowing a few minutes of contact and rinsing with water.