Method of using a chemical indicator

• US 6,485,978 B1
• Filed: 08/05/1999
• Issued: 11/26/2002
• Est. Priority Date: 08/05/1999
• Status: Expired due to Term

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Kirckof, Steven S., Bolea, Phillip A.
• Primary Examiner(s): ALEXANDER, LYLE
• Application Number:
  US09/368,744
• Time in Patent Office: 1,209 Days
• Field of Search: 422/58, 422/68, 422/28, 422/11, 422/56, 436/1, 436/164, 436/166, 436/169
• US Class Current: 436/1
• 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: G09F 3/0291 Labels or tickets undergoing a change under particular conditions, e.g. heat, radiation, passage of time
• CPC Class Codes: G09F 3/0297 including a machine-readable marking, e.g. a bar code digitally marked record carriers in general G06K19/00

Abstract

A sterilization indicator having sterilizing agent sensitive indicia is described. The indicator allows a sterilization cycle to be monitored without the need for a user to subjectively distinguish between color, quality or intensity of display patterns.

Claims

1. A method of monitoring the efficacy of a sterilization process comprising the steps of:

subjecting a chemical indicator to a sterilization process, the chemical indicator comprising;

i) a substrate having a surface, and ii) sterilizing agent sensitive indicia associated with said surface of said substrate, said indicia having;

(a) a first state prior to being exposed to the sterilization process, and (b) a second state after being exposed to said sterilization process, wherein the first state is different than said second state, and at least said second state is machine readable; and

scanning the indicia of the chemical indicator with a machine to obtain information relating to the sterilization process.

2. A method according to claim 1 wherein the indicia comprises a code and the step of scanning the indicia of the chemical indicator includes the step of reading the indicia of the chemical indicator with a code reader.

3. A method according to claim 2 wherein the indicia comprises a bar code and the step of scanning the indicia of the chemical indicator includes the step of reading the indicia with a bar code reader.

4. A method according to claim 1 wherein the first state is a first color and the second state is a second color, and the step of scanning the indicia of the chemical indicator includes the step of distinguishing said first color from said second color.

5. A method according to claim 4 wherein the step of distinguishing said first color from said second color comprises the steps of:

a) providing reference information,

b) reading information from said chemical indicator, and

c) comparing the information read from said chemical indicator with said reference information.

6. A method according to claim 1 wherein the step of subjecting a chemical indicator to a sterilization process comprises the step of subjecting a chemical indicator to a steam sterilization process.

7. A method according to claim 1 wherein the step of subjecting a chemical indicator to a sterilization process comprises the step of subjecting a chemical indicator to an ethylene oxide sterilization process.

8. A method according to claim 1 wherein the step of subjecting a chemical indicator to a sterilization process comprises the step of subjecting a chemical indicator to a hydrogen peroxide sterilization process.

9. A method according to claim 1 wherein one of the first and said second indications is not readable, and

said step of scanning the indicia includes the step of reading only one of said first and said second indications.

10. A method according to claim 1 wherein at least one of said first and second indications is readable and said step of scanning the indicia includes the step of reading said first and said second indications.

11. A method according to claim 1 wherein step of scanning the indicia includes the step of determining whether the chemical indicator has reacted to all critical parameters of a predetermined sterilization process.

12. A method according to claim 1 wherein step of scanning the indicia includes the step of determining whether the chemical indicator has reacted to time, temperature and saturated steam.

13. A method according to claim 1 further including the step of determining whether the sterilization process was an adequate sterilization process.

14. A method of monitoring the efficacy of a sterilization process comprising the steps of:

a) providing a chemical indicator comprising indication means having a first indicating state prior to being exposed to the sterilization process and a second indicating state after exposure to at least a portion of the sterilization process, such that the first indicating state is different than said second indicating state, and at least one of said first and said second states is machine readable;

b) subjecting the chemical indicator to the sterilization process,

c) scanning the chemical indicator with a machine to determine whether the sterilization process was adequate.