| Standard Operating Procedure | SOP No. |
| --- | --- |
| Biohazard Class II Cabinet Electrical Tests | 8.024 |

DCR No.: 03015  
Revision No.: 1

**Effective**: 3-5-99  
Supersedes: 3-5-99  
Revision Date: 11-15-03  
Page No.: **1 of 5**

## 1

## Purpose

1.1 To establish a standard procedure for measuring the electrical leakage,  
ground resistance, ground fault interrupter (GFI) performance and polarity  
of Class II Biohazard Cabinets manufactured before 2002.

## 2 Scope

2.1 This procedure applies to Class II Biohazard Cabinets manufactured  
before 2002.

## 3 Reference

3.1 NSF Standard 49, 2002  
3.2 NSF Standard 49, 1992 Annex F, Section II, Test Method F Subsection  
3c paragraph (3) for GFI’s procedure and standards of acceptance.

## 4 Definition

4.1 MA: milliampere  
4.2 µA: microampere

## 5 Responsibility

5.1 Test and Air Balance (TAB) technicians shall record all test measurements  
in electrical Test Section on Form FN 8.057.3 (Biohazard Safety Cabinet  
Test Report Details II) and indicate test result, Pass or Fail, on Form FN  
8.057.1 (Biohazard Safety Cabinet Test Report Summary Sheet).

5.2 All test reports shall be saved in files, located in the TAB department of  
Therma.

5.3 All test equipment utilized shall be in calibration in accordance with  
National Environment Balancing Bureau (NEBB) Standards and traceable  
to the National Institute of Standards and Technology (NIST).

---

| Revision No. | SOP No. | Page |
| --- | --- | --- |
| 1 | 8.024 | 2 of 5 |

## 8.1 Polarity

8.1.1 Use Leviton Circuit Tester to test the polarity and ground of the  
Biosafety Cabinet wall outlet.

8.1.2 Record Pass or Fail in the Polarity box under Electrical Tests  
Section on Form FN 8.057.3 (Biological Safety Cabinet Test Report Detail  
II sheet) .

## 8.2 Electrical Leakage

8.2.1 Plug the Ohmic SI-100N into a properly polarized and grounded  
120VAC outlet and switch it on.

8.2.2 Place the Selector switch in NORMAL (Left) position and depress  
the 100µA. Display should read 100µA. Switch SI-100N off.

$$
1 0 0 \mu \mathrm {A}.
$$

$$
100\ \mu{\mathsf{A}}
$$

8.2.3 Place all cabinet electrical switches in off position.

8.2.4 Plug cabinet main power cord into the LEAKAGE outlet of the SI-  
100N. Switch the SI-100N on.

8.2.5 Simulate an open ground by depressing and holding the OPEN  
GROUND switch.

8.2.6 Measure electrical leakage by contacting the cabinet work surface  
tray, cabinet inside wall, cabinet front, and cabinet drain handle  
with the probe (DO NOT PRESS THE BUTTON ON THE SIDE OF  
THE PROBE). If the measurement exceeds the display capability,  
depress the X10 Mult. Button to properly display the measurement.

8.2.7 Release the OPEN GROUND switch.

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| Revision No. | SOP No. | Page |
| --- | --- | --- |
| 1 | 8.024 | 3 of 5 |

8.2.8 Turn all cabinet electrical switches on.

8.2.9 Repeat steps 8.2.1 - 8.2.7

8.2.10 Repeat steps 8.2.2 - 8.2.9 with the SI-100N Selector switch in the  
REVERSE (Right) position.

8.2.11 Repeat steps 8.2.2 - 8.2.10 on any other power cord.

8.2.12 Record the highest µA measurement obtained in steps 8.2.6 -  
8.2.11 in the Electrical Leakage box under the Electrical Tests  
Section on Form FN 8.057.3 (Biological Safety Cabinet Test Report  
Detail II sheet).

8.2.13 To pass this test, the highest measurement shall not exceed 500  
µA.

## 8.3 Ground Resistance

$$
\mu A
$$

8.3.1 Place the SI-100N Selector switch in the RESISTANCE (Center)  
position. Insert the tip of the test probe into the 0.25-OHM TEST  
JACK. Depress the button on the probe and adjust the OHMS  
ADJUST knob until the display indicates 0.25 ohm.

8.3.2 Place all cabinet electrical switches in off position.

8.3.3 Plug cabinet main power cord into the GROUNDING outlet of the  
SI-100N. Switch the SI-100N on.

8.3.4 Measure ground resistance by contacting the cabinet work surface  
tray, cabinet inside wall, cabinet front, and cabinet drain handle  
with the probe and depressing the button located on the probe. If  
the measurement exceeds the display capability, depress the X10  
Mult. Button to properly display the measurement.

8.3.5 Place all cabinet electrical switches in on position.

8.3.6 The POOR INSUL. LED will come on if the combined hot-and  
neutral to ground resistance of the Biohazard Cabinet is less than  
1 megohm. Record in Notes section of the Test Sheet if the LED  
comes on.

8.3.7 Repeat step 8.3.4 with cabinet electrical switches in on position.

8.3.8 Repeat steps 8.3.2 - 8.3.7 on the other power cord, if any.

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| Revision No. | SOP No. | Page |
| --- | --- | --- |
| 1 | 8.024 | 4 of 5 |

8.3.9 Record the highest ohm measurement obtained in steps 8.3.4 -  
8.3.8 in the Ground Circuit Resistance box under the Electrical  
Tests Section on Form FN 8.057.3 (Biological Safety Cabinet Test  
Report Detail II sheet).

## 8.4 Ground Fault Interrupter (GFI) Test

8.3.10 The highest measurement shall not exceed 0.15 ohms.

8.4.1 Refer to NSF 49, 1992 Annex F, Section II, Test Method F,  
Subsection 3c paragraph (3) for procedure and standards of  
acceptance.

8.4.2 Record the ma setting in the GFI Trips box under Electrical  
Tests Section on Form FN 8.057.3 (Biological Safety Cabinet Test  
Report Detail II).

8.5 TAB technicians shall indicate Pass or Fail for the electrical tests, on  
Form FN 8.057.1 (Biohazard Safety Cabinet Test Report Summary  
Sheet).

## 9

## Review and Approval

9.1 TAB technicians shall return the Form FN 8.057.1 (Biohazard Safety  
Cabinet Test Report Summary Sheet) and the Form FN 8.057.3  
(Biological Safety Cabinet Test Report Detail II) to the TAB Department  
for review.

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| Revision No. | SOP No. | Page |
| --- | --- | --- |
| 1 | 8.024 | 5 of 5 |

## Document Approval

Test and Balance Supervisor  
Date  
Engineering Manager  
Quality Assurance Manager  
11-15-03  
Date