Systems and methods for determining the cleanliness of a surface

• US 9,839,712 B2
• Filed: 10/29/2013
• Issued: 12/12/2017
• Est. Priority Date: 12/21/2012
• Status: Active Grant

• Current Assignee: Solventum Intellectual Properties Company (Solventum Corp.)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Bommarito, G. Marco
• Primary Examiner(s): Geisel, Kara E
• Assistant Examiner(s): MERLINO, AMANDA H
• Application Number:
  US14/652,831
• Publication Number:
  US 20150328351A1
• Time in Patent Office: 1,505 Days
• CPC Class Codes: A61L 2/28 Devices for testing the effectiveness or completeness of sterilisation, e.g. indicators which change colour apparatus involving enzymes or microorganisms C12M1/34; methods involving enzymes or microorganisms C12Q1/00
• CPC Class Codes: B08B 13/00 Accessories or details of general applicability for machines or apparatus for cleaning
• CPC Class Codes: G01N 2021/551 Retroreflectance
• CPC Class Codes: G01N 21/4738 Diffuse reflection precedence is given to G01N21/55 - G01N21/57 if specular component is taken into consideration, e.g. also for testing fluids, fibrous materials
• CPC Class Codes: G01N 21/55 Specular reflectivity
• CPC Class Codes: G01N 21/94 Investigating contamination, e.g. dust G01N21/85 takes precedence
• CPC Class Codes: G01N 2201/061 Sources

Abstract

Systems and methods for determining the cleanliness of a surface. Surface marking systems of the present disclosure can include a plurality of retroreflective microspheres dispersed in or dispensed on a carrier. Applicators of the present disclosure can include a container comprising the surface marking system, and a dispenser. Methods of the present disclosure can include applying the surface marking system to at least one discrete site on the surface; illuminating the at least one discrete site on the surface with visible light, after a cleaning; and detecting retroreflection emitted from the at least one discrete site on the surface in response to illuminating the at least one discrete site to determine the effectiveness of the cleaning of the surface.

Claims

1. A method for determining the cleanliness of a surface, the method comprising:

providing a surface marking system comprising a plurality of retroreflective microspheres dispersed in or dispensed on a carrier;

applying the surface marking system to at least one discrete site on the surface;

illuminating the at least one discrete site on the surface with a visible light source, after a cleaning; and

detecting retroreflection emitted from the at least one discrete site on the surface in response to illuminating the at least one discrete site to determine the effectiveness of the cleaning of the surface.

2. The method of claim 1, wherein detecting includes visually detecting.

3. The method of claim 1, wherein the surface is an environmental surface.

4. The method of claim 1, wherein the at least one discrete site on the surface is unknown to environmental services staff.

5. The method of claim 1, wherein the surface marking system is covert.

6. The method of claim 1, wherein the plurality of retroreflective beads are randomly distributed in or on the carrier.

7. The method of claim 1, wherein applying the surface marking system includes foaming.

8. The method of claim 1, wherein applying the surface marking system includes dry transfer.

9. The method of claim 1, wherein applying the surface marking system includes contact application.

10. The method of claim 1, wherein applying the surface marking system includes liquid deposition.

11. The method of claim 1, wherein the plurality of retroreflective microspheres are dispersed in the carrier to a concentration of no greater than about 1×

10⁶ microspheres/mL of the carrier.

12. The method of claim 1, wherein the plurality of retroreflective microspheres includes an average diameter of 10 to 100 micrometers.

13. The method of claim 1, wherein the carrier includes at least one of a surfactant, a polymeric binder, an adhesive layer, and a combination thereof.

15. The method of claim 1, wherein the visible light source includes at least one of a flashlight, a lamp, a lantern, a camera, a smart phone, a smart phone camera, a tablet computer, a tablet computer camera, other portable devices with integrated flash cameras, and a combination thereof.

14. A system comprising:

a surface marking system comprising a plurality of retroreflective microspheres dispersed in or dispensed on a carrier, the surface marking system configured to be applied to at least one discrete site on a surface;

a visible light source configured to illuminate the at least one discrete site on the surface, after a cleaning; and

a detection device configured to detect retroreflection emitted from the at least one discrete site on the surface, while being illuminated by the visible light source, to determine the effectiveness of the cleaning of the surface.

16. The system of claim 14, wherein the visible light source includes at least one of a flashlight, a lamp, a lantern, a camera, a smart phone, a smart phone camera, a tablet computer, a tablet computer camera, other portable devices with integrated flash cameras, and a combination thereof.

17. The system of claim 14, wherein the detection device includes a camera.