Disinfecting aqueous foam, process for preparing same and use thereof

Abstract

The present invention relates to a foam consisting of a dispersion of gas bubbles in a foaming solution comprising, per litre of solution, (i) from 0.05 to 1.5% by weight of one or more foaming organic surfactant(s), (ii) from 0.05% to 0.8% by weight of one or more organic gelling or viscosifying agent(s), (iii) from 1% to 14% by volume of one or more disinfecting agent(s) and (iv) water, said foam having an expansion between 12.5 and 50. The present invention also relates to the use of such a foam for biological decontamination.

Claims

1. A foam of a dispersion of gas bubbles in a foaming solution, consisting of, per litre of the solution: from 0.05% to 1.5% by weight of at least one foaming organic surfactant, from 0.05% to 0.8% by weight of at least one organic gelling or viscosifying agent, from 1% to 14% by volume of at least one disinfecting agent, and water, wherein the foam has an expansion between 20 and 50.

2. The foam according to claim 1, wherein the at least one foaming organic surfactant is selected from the group consisting of a non-ionic foaming surfactant, an anionic foaming surfactant, and a cationic foaming surfactant.

3. The foam according to claim 1, wherein the at least one organic gelling or viscosifying agent is selected from the group consisting of a water-soluble polymer, a hydrocolloid, a heteropolysaccharide, a cellulose derivative, and a polysaccharide.

4. The foam according to claim 1, wherein the at least one disinfecting agent is selected from the group consisting of a chlorinated product, an aldehyde, and an oxidant.

5. The foam according to claim 1, wherein from 0.1 to 1.1% by weight of the at least one foaming organic surfactant, from 0.15% to 0.3% by weight of the at least one organic gelling or viscosifying agent, and either from 2% to 7.5% by volume or from 5% to 14% by volume of the at least one disinfecting agent or of a mixture of disinfecting agents are present in the foaming solution.

6. The foam according to claim 1, wherein from 0.1 to 1.1% by weight of an alkylpolyglucoside, from 0.15% to 0.3% by weight of xanthan gum, and either from 2% to 7.5% by volume or from 5% to 14% by volume of sodium hypochlorite or hydrogen peroxide are present in the foaming solution.

7. A method for treating a surface contaminated with at least one biological agent, the method comprising: contacting the surface with the foam according to claim 1.

8. The method according to claim 7, wherein the surface is made of a metal, metal alloy, steel, tinplate, silicon, glass containing silicate, silica glass, ceramic, brick, porcelain, cement, concrete, asphalt, stone, granite, wood, clay, plastic or a combination thereof.

9. The method according to claim 7, wherein the biological agent is at least one species or bio-toxic element selected from the group consisting of a pathogenic spore, Gram negative bacteria, Gram positive bacteria, a toxin, and a virus.

10. The method according to claim 7, wherein the contacting is performed by: applying, on the surface, the foam by spraying or by floating or filling a structure containing the surface with the foam.

11. The method according to claim 10, further comprising: after the contacting, drying sprayed or floated foam by evaporation, or draining foam used in a filling mode.

12. The method according to claim 7, further comprising: after the contacting, either retrieving the foam by suction before complete drying or retrieving a dry residue of the foam by suction or by wiping.

Description

BRIEF DESCRIPTION OF THE FIGURES

(1) FIG. 1 shows the mean evaluation of the decontamination efficacy of a foam according to the invention containing different concentrations of sodium hypochlorite (FIG. 1A) or different concentrations of hydrogen peroxide (FIG. 1B).

(2) FIG. 2 shows the mean rate of decontamination of a foam according to the invention containing sodium hypochlorite (FIG. 2A) or hydrogen peroxide (FIG. 2B).

(3) FIG. 3 is a schematic representation of the experimental protocol used for evaluating the efficacy of a foam according to the invention on earthenware tiles.

(4) FIG. 4 shows the evaluation of the decontamination efficacy of a foam according to the invention containing sodium hypochlorite or hydrogen peroxide on earthenware tiles (FIG. 4A) or on aluminium plate (FIG. 4B).

(5) FIG. 5 shows the evaluation of the decontamination efficacy of a foam according to the invention containing sodium hypochlorite or hydrogen peroxide on vertical walls.

(6) FIG. 6 shows the evaluation of the decontamination efficacy of a foam according to the invention containing sodium hypochlorite or hydrogen peroxide in filling mode.

(7) FIG. 7 shows the evaluation of the decontamination efficacy of a foam according to the invention containing sodium hypochlorite or hydrogen peroxide and having different moisture percentages.

(8) FIG. 8 shows the evaluation of the decontamination efficacy of a foam according to the invention containing sodium hypochlorite or hydrogen peroxide after ageing of the initial foaming solutions.

(9) FIG. 9 shows a comparison of the foamability and drainage at t=0, t=1 wk and t=5 wks of storage, of a foam according to the invention containing sodium hypochlorite (FIG. 9A) or hydrogen peroxide (FIG. 9B).

(10) FIG. 10 shows the slippage kinetics of an application of a foam according to the invention containing sodium hypochlorite or hydrogen peroxide on a wipe-off marker whiteboard.

(11) FIG. 11 shows the evaporation kinetics of a neutral foam (FIG. 11A) or of a foam according to the invention containing sodium hypochlorite (FIG. 11B) or hydrogen peroxide (FIG. 11C), all of these foams optionally containing 1.5 g/l or 3 g/l of xanthan, as viscosifying agent.

DETAILED DESCRIPTION OF PARTICULAR EMBODIMENTS

(12) I. Formulations Used for Foam.

(13) The various formulations of the following solutions used during the tests presented hereinafter are contained in Table 1 hereinafter:

(14) TABLE-US-00001 TABLE 1 Concentration per Litre of Name of formulation Composition foaming solution Neutral, 1.5 g/l of Xanthan H.sub.2O 839 ml/L Glucopon 11 g/L 10 g/l Xanthan 150 ml/L Neutral, 2 g/l of Xanthan H.sub.2O 789 ml/L Glucopon 11 g/L 10 g/l Xanthan 200 ml/L Neutral, 2.5 g/l of Xanthan H.sub.2O 739 ml/L Glucopon 11 g/L 10 g/l Xanthan 250 ml/L Neutral, 3 g/l of Xanthan H.sub.2O 689 ml/L Glucopon 11 g/L 10 g/l Xanthan 300 ml/L 1% NaOCl H.sub.2O 768 ml/L Glucopon 11 g/L 10 g/l Xanthan 150 ml/L 14% NaOCl 71 ml/L 2% NaOCl H.sub.2O 696 ml/L Glucopon 11 g/L 10 g/l Xanthan 150 ml/L 14% NaOCl 143 ml/L 3% NaOCl H.sub.2O 625 ml/L Glucopon 11 g/L 10 g/l Xanthan 150 ml/L 14% NaOCl 214 ml/L 4% NaOCl H.sub.2O 553 ml/L Glucopon 11 g/L 10 g/l Xanthan 150 ml/L 14% NaOCl 286 ml/L 5% NaOCl and 1.5 g/l H.sub.2O 482 ml/L Xanthan Glucopon 11 ml/L 10 g/l Xanthan 150 ml/L 14% NaOCl 357 ml/L 5% NaOCl and 2 g/l Xanthan H.sub.2O 431 ml/L Glucopon 11 g/L 10 g/l Xanthan 200 ml/L 14% NaOCl 358 ml/L 5% NaOCl and 2.5 g/l H.sub.2O 381 ml/L Xanthan Glucopon 11 g/L 10 g/l Xanthan 250 ml/L 14% NaOCl 358 ml/L 5% NaOCl and 3 g/l Xanthan H.sub.2O 331 ml/L Glucopon 11 g/L 10 g/l Xanthan 300 ml/L 14% NaOCl 358 ml/L 7.5% NaOCl H.sub.2O 303 ml/L Glucopon 11 g/L 10 g/l Xanthan 150 ml/L 14% NaOCl 536 ml/L 1% H2O2 H.sub.2O 806 ml/L Glucopon 11 g/L 10 g/l Xanthan 150 ml/L 30% H2O2 33 ml/L 2% H2O2 H.sub.2O 772 ml/L Glucopon 11 g/L 10 g/l Xanthan 150 ml/L 30% H2O2 67 ml/L 5% H2O2 and 1.5 g/l H.sub.2O 672 ml/L Xanthan Glucopon 11 g/L 10 g/l Xanthan 150 ml/L 30% H2O2 167 ml/L H2O2 5% and 2 g/l Xanthan H.sub.2O 622 ml/L Glucopon 11 g/L 10 g/l Xanthan 200 ml/L 30% H2O2 167 ml/L H2O2 5% and 2.5 g/l H.sub.2O 572 ml/L Xanthan Glucopon 11 g/L 10 g/l Xanthan 250 ml/L 30% H2O2 167 ml/L 5% H2O2 and 3 g/l Xanthan H.sub.2O 523 ml/L Glucopon 11 g/L 10 g/l Xanthan 300 ml/L 30% H2O2 167 ml/L 8% H2O2 H.sub.2O 574 ml/L Glucopon 11 g/L 10 g/l Xanthan 150 ml/L 30% H2O2 265 ml/L
II. Biological Test Operating Protocol.

(15) The tests are conducted with spores of Bacillus thuringiensis (Bt) which is a simili of Bacillus anthracis, in a biosafety cabinet (BSC) allocated to spores in an L2 microbiology laboratory. Petri dishes are contaminated with 100 l of a solution containing 10.sup.8 spores of Bt/ml, i.e. a deposit of 10.sup.7 spores of Bt, which is allowed to dry completely under the hood (approximately 1 hr 30).

(16) The foaming solutions are prepared in the laboratory with a static generator with beads. The foams are generated in a 2-litre beaker and then weighed to determine the moisture of the foam. The foams are then deposited onto the spores using a spatula.

(17) The foams remain in contact with the spores with the dishes closed, for 1 hr to 1 hr 30 approximately or according to the test protocol (example for the biocidal action rate).

(18) For each dish, the spores are taken up by depositing sterile water on several occasions and placed in one or a plurality of Falcon tubes made up to 45 ml. The Falcon tubes are centrifuged for 15 min at 4000 rpm.

(19) The supernatant is removed and the pellet is re-suspended in 10 ml of liquid Luria-Broth (LB) nutrient broth, and then vortexed. If the same dish has required the use of a plurality of Falcon tubes, the tubes are combined into one. The Falcon tubes are placed in an incubator at 30 C. for 1 hr.

(20) This incubation in LB medium enables the initiation of the desporulation of Bacillus thuringiensis spores which are converted into vegetative form at the correct temperature, and prolonged contacting of the substrate with the medium in order to retrieve a maximum number of spores present on the substrate. These vegetative forms may grow in the form of colonies on a solid nutrient medium (agar) in Petri dishes and thus be counted visually. This enables an estimation of the number of initial spores inactivated.

(21) For each of the tubes incubated at 30 C., a series of ten-fold (factors of 10) successive dilutions by volume is produced with liquid LB (dilution to 10.sup.8 or to one hundred millionth). Finally, 1 ml is taken up into each of the tubes of each series of dilutions, and is then deposited onto the bottom of a sterile empty Petri dish.

(22) LB agar medium is then poured into the dish (inoculation throughout). The dishes are then placed in an incubator at 30 C. for approximately 20 hrs. The colonies are counted one by one and a mean live spore count is calculated. A test containing no disinfectant, referred to as Neutral, is conducted at least once for each test, so as to check that the operating protocol has been applied correctly.

(23) III. Evaluation of the Biocidal Efficacy of the Formulation.

(24) III.1. Foams with Different Sodium Hypochlorite and Hydrogen Peroxide Concentrations.

(25) Tests are conducted in order to determine the biocidal efficacy at different NaOCl and H.sub.2O.sub.2 concentrations. These tests are conducted according to the operating protocol described above and according to the formulations detailed above.

(26) As such, three tests were conducted for 5% NaOCl, two tests for 5% H.sub.2O.sub.2 and one test for 1%, 2%, 3%, 4% and 7.5% NaOCl, as well as for 1% and 2% H.sub.2O.sub.2.

(27) The results of these tests are shown in FIGS. 1A and 1B. It emerges that the foam according to the present invention with sodium hypochlorite is effective from a concentration of 1% sodium hypochlorite and that with hydrogen peroxide is effective from a concentration of 2% hydrogen peroxide.

(28) III.2. Evaluation of Foam Decontamination Rates.

(29) Tests are conducted in order to determine the biocidal efficacy rate of the NaOCl and H.sub.2O.sub.2 foams. These tests are conducted according to the operating protocol described above.

(30) The contact time between the foam and the spores is measured with a timer. Foam/contamination contact times of 30 s, 5 min, 7 min, 10 min, 15 min, 30 min, 45 min and 1 hr were tested. However, it is necessary to take into account the irreducible treatment time due to the experimental protocol (foam retrieval and centrifugation) of approximately 20 min. The foam retrieved is diluted with sterilised water; therefore the disinfectant is at a lower concentration and the foam is broken down.

(31) The number of reproductions of these tests is shown in Table 2 hereinafter:

(32) TABLE-US-00002 TABLE 2 Contact time Number of 5% NaOCl tests Number of 5% H.sub.2O.sub.2 tests 30 seconds 2 2 5 minutes 1 7 minutes 2 2 10 minutes 1 13 minutes 2 1 15 minutes 2 3 30 minutes 2 2 45 minutes 2 2 60 minutes 4 4

(33) The results of these tests are shown in FIGS. 2A and 2B. As such, the foam containing 5% sodium hypochlorite and that containing 5% hydrogen peroxide neutralise all of the spores (approximately 10.sup.7 spores) from 5 min and 13 min of contact, respectively. It is necessary to add, to these contact times, the treatment time due to the experimental protocol, making it possible to state that the solutions are effective in 30 min; therefore, both disinfectants are effective in less than one hour.

(34) III.3. Valuation of Decontamination Efficacy of Foams on Various Substrates.

(35) Tests are conducted in order to determine the biocidal efficacy of NaOCl and H.sub.2O.sub.2 foams on various materials. The tests follow the operating protocol described above apart from the depositions which are carried out on an earthenware tile or on an aluminium plate placed in a Petri dish with a contact time between the foam and the contaminated material of 30 min (FIG. 3).

(36) The contaminated material is placed in a tube with 30 ml of liquid Luria-Broth (LB) nutrient medium and incubated for 1 hr at 30 C. This incubation makes it possible to initiate the desporulation of Bacillus thuringiensis spores which are converted into vegetative form and prolong the contact time with the substrate in order to check that no spores remain on the earthenware tile or aluminium plate.

(37) For each of the tubes incubated at 30 C., a series of ten-fold (factors of 10) successive dilutions by volume is produced with liquid LB (dilution to 101 or to one hundred millionth). Finally, 1 ml is taken up into each of the tubes of each series of dilutions, and is then deposited onto the bottom of a sterile empty Petri dish. LB agar medium is then poured into the dish (inoculation throughout). The dishes are then placed in an incubator at 30 C. for approximately 20 hrs. The colonies are counted one by one and a mean live spore count is calculated. The decontamination factor may be calculated by determining the reduction in thousands of spores killed (log.sub.10).

(38) The results of these tests conducted on earthenware tile or aluminium plate are shown in FIGS. 4A and 4B. The foams according to the invention with 5% sodium hypochlorite and with 5% hydrogen peroxide are effective on earthenware tiles in 30 min. On aluminium plates, only bleach by way of disinfecting agent was tested and a foam according to the invention containing 5% sodium hypochlorite is also effective in 30 min on such a substrate.

(39) III.4. Evaluation of Decontamination Efficacy of Foams on Vertical Wall.

(40) Tests are conducted in order to determine the biocidal efficacy of NaOCl and H.sub.2O.sub.2 foams on a vertical wall. These tests are conducted according to the operating protocol described above with rectangular dishes and according to the formulations detailed above.

(41) For these tests on a vertical wall, the foam applied forms a cone, the base whereof rests on the bottom of the dish and rises up the vertical wall. The contamination zone remains covered by the foam.

(42) For the tests on a vertical wall, one test with the 5% NaOCl foam and two tests with a 5% H.sub.2O.sub.2 foam were conducted. The results of these tests are shown in FIG. 5. The 5% NaOCl and 5% H.sub.2O.sub.2 have physicochemical properties and a rate of action enabling them to have a sufficient contact time with the vertical wall to decontaminate the latter.

(43) III.5. Evaluation of Decontamination Efficacy of Foams in Filling Mode.

(44) Tests are conducted in order to determine the biocidal efficacy of NaOCl and H.sub.2O.sub.2 foams in filling mode. These tests are conducted according to the operating protocol described above with containers which may be rectangular dishes or tubes and according to the formulations detailed above. Contamination is performed on two of the vertical walls of the dish (50 l of solution containing 10.sup.8 spores/ml on each wall) or on the vertical wall of the tube.

(45) For the tests in filling mode, six tests with a 5% NaOCl foam, one test with a 7.5% NaOCl foam and five tests with a 5% H.sub.2O.sub.2 foam were conducted. The results of these tests are shown in FIG. 6. The various types of foam tests are suitable for decontaminating enclosed spaces in filling mode.

(46) III.6. Evaluation of Decontamination Efficacy of Foams According to Moisture Percentage.

(47) Tests are conducted in order to determine the biocidal efficacy of NaOCl and H.sub.2O.sub.2 foams at different moisture percentages. These tests are conducted according to the biological operating protocol and according to the formulations detailed above.

(48) The moisture percentage of the foam is modified following changes in foam generator settings. The generator is thus configured a first time to obtain foams with 2.5% moisture and a second time to obtain 3% moisture. A test was conducted with a NaOCl foam at 3.5% moisture and another at 4%. The same applied for an H.sub.2O.sub.2 for which a test was conducted at 2.7% and another at 2.8% moisture.

(49) The results of these tests are shown in FIG. 7. The NaOCl foam is effective from 3.5% moisture (expansion 28.5) and the H.sub.2O.sub.2 from 2.7% moisture (expansion 37).

(50) III.7. Evaluation of Decontamination Efficacy of Foams after Ageing of Solutions.

(51) Tests are conducted in order to determine the biocidal efficacy of NaOCl and H.sub.2O.sub.2 foams after several weeks of storage. These tests are conducted according to the biological operating protocol and according to the formulations detailed above.

(52) Tests are performed on the day of preparation of the solutions (t=0), 1 week after (t=1 wk), 2 weeks after (t=2 wk) and 5 weeks after the preparation thereof (t=5 wk). The initial liquid solutions from which the foams are produced are stored in a cold store at 4 C. for the ageing time.

(53) A test is conducted with a 5% NaOCl foam and a 5% H.sub.2O.sub.2 foam at each ageing time. The results of these tests are shown in FIG. 8. The foams retain Bt spore decontamination potential even after 5 weeks of storage of the initial foaming solution.

(54) III.8. Evaluation of Foamability of Foaming Solutions and Stability Over Time of Corresponding Foams.

(55) Foaming experiments are conducted in order to determine the foamability of the NaOCl and H.sub.2O.sub.2 after several weeks of storage. These experiments are conducted with a commercial apparatus called Foamscan from Teclis. It is used to measure, in a 150 ml column and with an initial solution volume of 20 ml, not only the foaming rate for a given air flow rate (determined at 100 ml) but also the stability of the foam by stopping air injection.

(56) Therefore, a measurement is made, as a function of time, of the reduction in the quantity of liquid in the column until air injection is stopped (approximately 60 seconds, see FIGS. 9A and 9B). Then, from the time the gas is stopped, the quantity of liquid in the column increases more or less quickly, indicating the drainage of the foam and thereof the stability thereof.

(57) In the presence of a viscosifying agent such as xanthan, a delay in the onset of drainage may be observed which is indicated by the existence of a plateau before the increase in the level of liquid in the column. The duration of this plateau indicates the stability of the foam. The ageing results obtained at t=0, t=1 wk and t=5 wk, are illustrated in FIG. 9.

(58) As such, for the 5% sodium hypochlorite solution and a quantity of xanthan of 1.5 g/l (FIG. 9A), all the curves show an identical and total transfer (first part of the curve) of liquid into the foam. The decrease is linear indicating that all of the air injected is captured to form the foam. After switching off the air, the fresh foam (t=0 wk) exhibits a plateau of approximately 180 s, then drainage starts slowly: after 10 min, only 25% of the liquid has drained. After 1 week of storage, while the foamability is identical, the stability, on the other hand, is lower: the drainage delay plateau observed is merely 40 s and the drainage is more rapid (75% of liquid drains in 10 min). The decontamination efficacy tests demonstrated that the biocidal solution remains foaming and that the corresponding NaOCl foam remains active after 5 weeks of storage.

(59) For the 5% hydrogen peroxide solution and a quantity of xanthan of 1.5 g/l (FIG. 9B), all the curves show an identical and total transfer (first part of the curve) of liquid into the foam. The decrease is linear indicating that all of the air injected is captured to form the foam. After switching off the air, all of the foams exhibit a drainage delay greater than 10 min. The H.sub.2O.sub.2 foams are more stable than the NaOCl foams.

(60) III.9. Evaluation of the Adhesion of Foams on a Vertical Wall According to Different Xanthan Concentrations.

(61) These tests are intended to determine the adhesion of foam deposits on a vertical wall by measuring the slippage of the foam over time. Foam deposits of 3 different sizes were carried out with different solutions according to the present invention and with different concentrations of xanthan which is the viscosifying agent of the formulation. For these tests, four xanthan concentrations are tested: 1.5 g/l, 2 g/l, 2.5 g/l and 3 g/l.

(62) These tests are conducted with, as a substrate, a wipe-off marker whiteboard. This is a non-porous and very smooth material which makes it possible to conduct these tests under the most difficult conditions. The position of the deposit at t=0 is recorded and, after various times have elapsed, the slippage distance of the foam is measured.

(63) The NaOCl and H.sub.2O.sub.2 foams adhere to the surface of a wipe-off marker whiteboard. The slippage of the foam is slowed down considerably (mean slippage of 3 cm in 30 min) when the xanthan concentration is increased to 3 g/l (FIG. 10).

(64) III.10. Evaluation of Evaporation of Different Foams.

(65) Tests are conducted in order to determine the evaporation rate of a layer of foam and the influence of the disinfecting agents thereon. These tests are conducted using a controlled-temperature and hygrometry climatic chamber. It consists of evaporating horizontally approximately 24 cm.sup.3 (4 cm4 cm1.5 cm) of foam in a stainless steel boat while measuring the loss of mass over time, using a precision balance. The climatic chamber is set to a temperature of 22 C. and a relative humidity of 40%.

(66) The foam is generated by a static generator with beads and deposited in the stainless steel boat. The latter is then placed in the balance situated in the climatic chamber. The balance is entirely enclosed. It indicates the mass of the foam contained in the boat, the boat having been previously calibrated. A software program is used to record, every 10 min, the mass measured by the balance in real time. A second software program is used to take photos inside the balance.

(67) The foams generated for these tests are 5% NaOCl, 5% H.sub.2O.sub.2 and neutral foams with 1.5 g/l or 3 g/l of xanthan. The duration of the tests is overnight or over a weekend.

(68) The results of these tests are shown in FIG. 11 with the tests for the neutral foams, NaOCl foams and H.sub.2O.sub.2 foams in FIGS. 11A, 11B and 11C, respectively. The evaporation rate is constant for at least 300 min then starts to decrease for a low foam mass. It is also observed that, with NaOCl foams (FIG. 11B), after evaporation, a residue of sodium chloride and sodium carbonate crystals remains, the mass whereof is low but measurable. By calculating the slope equation over the first 300 minutes (linear regression), it is observed that the directional coefficients of the slopes of all of the evaporation tests are relatively similar (mean 0.0019+/0.0003), either with or without disinfectant and at both xanthan concentrations. A test with a layer of water was conducted and the evaporation displays the same kinetics. Therefore, the initial evaporation does not appear to be influenced by the foam formulation and corresponds to the water evaporation. For 1 g of foam spread over 4 cm by 4 cm and over a thickness of 1.5 cm, evaporation is performed on average in 9 hours.

(69) These tests were supplemented by depositing a layer of 5% NaOCl foam deposited with a spatula on a plastic vertical surface contaminated with Bt spore spots. This experiment was conducted under a ventilated hood in which the air flow accelerates the evaporation rate.

(70) The decontamination efficacy measurements on Bt spores, according to the biological operating protocol above, exhibit excellent efficacy (greater than 10.sup.6 inactivated spores).

(71) As such, in 14 hours, the foam layer had entirely disappeared and the foam liquid evaporated. After evaporation, a thin, transparent film of glucopon and xanthan is observed, for each foam. Furthermore, for the NaOCl foam, small sodium chloride and sodium carbonate crystals resulting from the evaporation reaction are also observed.

(72) III.11. Evaluation of Retrieval of Foam by Suction.

(73) Foam retrieval tests by suction were conducted with a liquid suction machine.

(74) For this purpose, a 1 to 3 cm thick layer of a foam according to the invention was applied by floating onto a vertical wall or a 301 container was filled with a foam according to the invention. In both applications modes i.e. floating or filling, the foam is suitable for suction.

REFERENCES

(75) [1] EFT Holdings Inc. MATERIAL SAFETY DATA SHEET NAME OF FINISHED SOLUTION: EasyDECON DF200-531X Alabama 2008. http://www.easydecon.com/easydecon/EasyDECON%20DF200%20MSDS.pdf [2] Patent application U.S. Pat. No. 7,276,468 on behalf of Sandia Corporation, granted on 2 Oct. 2007. [3] EFT Holdings Inc. Performance Data Alabama 2011. http://www.easydecon.com/easydecon/FactSheete248.html [4] Allen VanguardCASCAD Decontamination Foam, 2009. http://reports.hms-online.org/ViewProduct.aspx?CategoryId=175&ProductId=721 [5] Biological Agent Decontamination Technology Testing U.S. EPA. Biological Agent Decontamination Technology Testing. U.S. Environmental Protection Agency, Washington, D.C., EPA/600/R-10/087, 2010. [6] International application WO 2004/008463 on behalf of CEA and COGEMA, published on 22 Jan. 2004. [7] A quantitative kinetic theory of emulsion type, I. Physical chemistry of the emulsifying agent Gas/Liquid and Liquid/Liquid Interface. Proceedings of the International Congress of Surface Activity (1957): 426-438. [8] Regulation (EU) No. 528/2012 of 22 May 2012 concerning the provision on the market and use of biocidal products. [9] International application WO 02/043847 on behalf of CEA, published on 6 Jun. 2002.