SOP Title: Procedure for Efficiency test for UV Light
- Objective:
To lay down the procedure for determination of Efficiency test for UV Light.
- Scope:
This procedure is applicable for determination of Efficiency test for UV Light in the Microbiology Section.
- Responsibility:
- Quality Control: To prepare and review the SOP. To follow the procedures for determination of Efficiency test for UV Light as per this SOP.
- Quality Assurance Department: To review and approve the SOP and Annexure.
- Accountability:
Head Quality Control Department, Head Quality Assurance Department.
- Procedure:
| 5.1 | Safety Precautions: | |
| 5.1.1 | Always wear protective mask and gloves while performing micro activities. | |
| 5.1.2 | Use clean spatula, preferably wiped and dried with 70% v/v Isopropyl Alcohol for weighing of each media. | |
| 5.1.3 | Switch OFF the UV light before collecting the plates. | |
| 5.2 | UV Efficacy Study test of UV light | |
| 5.2.1 | Frequency: Half Yearly | |
| 5.2.2 | Applicable to Sampling booth RLAF and Pass box, Dispensing booth RLAF and pass box, Microbiology Section LAF and Pass boxes. | |
| 5.3 | Procedure to Determine the UV light Efficiency test: | |
| 5.3.1 | Transfer the required weighed quantity of SCDA media based on the number of UV light tubes and the positive and negative controls petriplates to a suitable flask and proceeds as per SOP for preparation of Culture media. | |
| 5.3.2 | Aseptically pour 15-20 ml of sterile molten SCDA media cooled at approximately 45°C in required number of 90 mm Petri plates under LAF.
Ensure that the plates are prepared in duplicates, one exposed and the other for unexposed test. |
|
| 5.3.3 | After solidification, incubate the plates at 30-35°C for 24 hours. | |
| 5.3.4 | After pre-incubation, transfer not less than 100 cfu per 0.1 ml culture of Bacillus subtilis (as it is one of the most resistant bacteria) on to SCDA plates using a sterile pipette and spread the colony using sterile spreader. Prepare of serial dilution cultures to get 100 CFU per 0.1 ml cultures as per SOP. | |
| 5.3.5 | Wrap one petriplate with Aluminium foil and second one keep as it is. | |
| 5.3.6 | Under LAF, open the lid of unwrapped petri plate. Follow the same procedure for Sampling Booth, Dispensing booth and Pass boxes. Keep Wrapped plate as it is under UV light along with unwrapped plate. | |
| 5.3.7 | Switch ON the UV light for 30 minutes. | |
| 5.3.8 | After 30 minutes of exposure switch OFF the UV light and close the lid of unwrapped petriplate. | |
| 5.3.9 | Simultaneously carry out positive control by streaking Bacillus subtilis and negative control without streaking onto SCDA plates. | |
| 5.3.10 | Incubate all the test plates along with control plate at 30-350C for 24 hours. | |
| 5.3.11 | After incubation observe the plates for total bacterial count and record the results in annexure. | |
| 5.4 | Limit /Acceptance criteria: | |
| 5.4.1 | 1) There should be no growth in unwrapped petriplate and there should be growth in wrapped Aluminium foil petriplate.
2) There should be growth on positive control and no growth on negative control. |
|
| 5.4.2 | After recording of all results, decontaminate the plates and other used media by referring SOP, Decontamination of culture media and microbial waste. | |
| 5.4.3 | If the UV efficacy test fails, investigate the cause and replace the tube if necessary. Perform efficacy test on new UV tube. | |
| 5.4.4 | UV Burning hours for a UV tube should not exceed 2000 hours. | |
- Definitions / Abbreviations:
- Definitions:
- Abbreviations:
| Abbreviation | Expansion |
| LAF | Laminar Air Flow |
| SCDA | Soyabean Casein Digest Agar |
| UV | Ultra Violet |
| °C | Degree centigrade |
| v/v | Volume by volume |
| ml | milliliter |
| mm | millimeter |
| % | Percentage |
*Note – Ready to use SOP available in “DOWNLOAD” Section.