Gas Cylinder Cabinet

DCR No.: 97033

Effective: 3-7-97

Supersedes: 5-7-97

Revision No.: 2

Revision Date: 7-25-97

Page No.: 1 of 4

1

Purpose

1.1 To establish a standard procedure for testing the exhaust ventilation of gas cylinder cabinet(s) to comply with local city HAZMAT requirements and codes.

2 Scope

2.1 This procedure applies to the gas cylinder cabinet(s).

3 Reference

3.1 Local City HAZMAT Requirements and Codes.

4 Definition

4.1 CFM Cubic Feet per Minute
4.2 FPM Feet Per Minute
4.3 TAB Test, Adjust, and Balance

5 Responsibility

5.1 TAB technician(s) shall record all test readings on an appropriate Gas Cylinder Cabinet Certification Report, Form FN 8.010.1 or FN 8.010.2.

5.2 TAB technician(s) shall attach a PASS or FAIL label to the cabinet with date and initial of TAB technician(s) as the testing is complete.

5.3 All test reports shall be saved in files, located in the TAB Department of Therma.

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

7 Test Equipment

8 General Procedures

8.1 Prior to commencing work, ensure that the exhaust fan is operating and that the cabinet is under negative pressure in relation to the surrounding area.

8.2 Record all required information, including room number(s), cabinet number(s), gas contents, design airflow volume and design velocities.

8.3 Measure the dimensions of the cabinet.

8.4 Calculate the area of the service window or cabinet footprint.

Note: When four or more cabinets are served by the same fan or branch duct, open the door of an alternative cabinet during testing.

8.5 Verify that the exhaust damper is not closed.

8.6 Verify that the cabinet is in normal operating mode:

8.6.1 Cabinet air inlets are free of derbies.

8.6.2 Any filters are in good condition.

8.7 Holding the service window open, measure the velocities in the geometric center of equal area within the net free area of the open service window using an anemometer.

8.8 Calculate the average velocity by dividing the total of the measured velocities by the number of readings.

8.9 Verify that the average velocity is not less than 200 linear FPM with a minimum velocity of 150 linear FPM.

8.10 Calculate the exhausted air volume in CFM through the open service window using the following equation:

Exhausted Air Volume (CFM) = Area x Average Velocity

Note: Cylinders located inside of gas cabinets shall be exhausted to a minimum of 300 CFM for a two-cylinder cabinet, and 450 CFM for a three-cylinder cabinet.

8.11 Measure the final exhausted air volume with the cabinet in normal operating mode [door(s) and service window(s) are closed].

Note: Silane compounds (pyrophorics): the exhausted volume shall equal not less than the area of the cabinet footprint in square feet times 200 FPM.

8.12 Record all data on an appropriate Gas Cylinder Cabinet Certification Report, Form FN 8.010.1 or FN 8.010.2.

8.13 Attach a PASS or FAIL label to the gas cylinder cabinet with date and the initial of TAB technician(s). If it is a PASS label, issue a PASS certification for the gas cylinder cabinet. Otherwise, notify the customer(s).

9 Review and Approval

9.1 Return the Gas Cylinder Cabinet Certification Report to the TAB Department for review.

Document Approval

General Foreman

7-2 Date
2-9.7

7-22 Date

-97

Richard

this

Quality Assurance Manager

7-23 Date

-97