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DIVISION OF FACILITIESPolicy and Procedures Manual

No.

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Revision

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Date10/21/09

Page1 of 4

OPERATING POLICY - Final Fume Hood Maintenance Policy^

PURPOSE: To establish a protocol necessary to safeguard workers when responding to equipmentfailures and scheduled maintenance on chemical fume hoods. For testing the fume hoodspersonnel must wear at a minimum gloves and goggles follow “Appendix A” algorithm.Facilities personnel will not be allowed to work on perchloric acid hoods.

DEFINITIONS:

Fume hoods are air capturing devices used primarily in laboratories protect the user from toxic orcorrosive vapors. For the most part, on campus fume hoods are used to move low hazard ornoxious vapors away from the breathing zone of the worker. However, there are some instanceswhere high hazards are involved. These high hazard instances occur when fume hoods are usedto exhaust:

Radioactive Materials or Isotopes. Radioactive materials do not make the componentsof the fume hoods radioactive. Under normal circumstances the radioactivity is carried away in theeffluent and does not coat the inside of the fume hood system. Occasionally, radioactive iodine isused in the fume hood and in this instance the iodine could bind with contaminants on the insideof the system making it radioactive. The radioactivity is very short lived however. The Departmentof Environmental Health and Safety can perform a simple test to detect this radioactivity.Radioisotope hoods must be properly cleaned by a laboratory worker prior to service. Facilitiespersonnel should not perform work in radioactive hoods without testing from EH&S.

Acid or alkali digestion. Some hoods are used for acid or alkali digestion. This processgenerates or uses quite a bit of heat and therefore a strong acid or base vapor is produced. Thevapor can coat the inside of the hood and/or the duct with a strongly acidic or basic residue. TheFacilities personnel can perform a simple PH test to detect this residue.

Perchloric acid digestion. A special acid digestion process that is only permitted in specialperchloric acid fume hoods. The digestion process produces volatile perchlorates that can combinewith contaminants to produce an explosive residue. For this reason, wash down hoods areemployed with perchloric acid digestion. The wash down should drench all surfaces of the fan, duct,and inside of the fume hood to prevent the build-up of dangerous perchlorates. The Department ofEnvironmental Health and Safety can perform a simple test to detect perchlorates, but allcontaminated surfaces must be washed down or steam cleaned prior to service. Facilitiespersonnel are not allowed to work on perchloric acid fume hoods.

Volatile organic compounds (VOC’s). The majority of chemicals used inside fume hoodsare VOC’s. These include solvents life benzene, alcohols, ethers, and the halgenated solvents like

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methylene chloride and chloroform. These halogenated and nonhalogenated compounds do notcollect in a functioning fume hood. The Facilities personnel can use an electronic monitor such asphotoionization detector (PID) to detect the presence of VOC’s.

Gases. Most gases will be carried away in a functioning fume hood. The exception arethose gases which are heavier than air like bromine. If the fume hood is not functioning properly,these heavy gases can collect in the duct work by condensation and remain a liquid on the surface.The Facilities personnel can perform a simple pH test to detect contaminants.

Contamination in fume hoods typically is found on the work surface of the hood, the lowest sixinches of the baffle on the back side, the inside surface of the glass sash, and the area on top ofthe hood (Make-up air hoods primarily). The interior of ducts in the fume hoods system can also bea source of contamination to the hands and/or arms.

PROCEDURE:

Working Inside Fume Hood Envelop

1. Minor Repairs will receive a work order indicating the need for chemical fume hood servicing.

2. Minor Repairs will be responsible to contact the Building User to clean the chemical fume hoodin accordance to departmental guidelines. The Building User will ensure that fume hoods contentsare emptied, inside of hood cleaned which includes all cabinets vented into the fume hood.

3. Facilities servicing personnel will follow the guidelines provided by Environmental Health andSafety (Appendix A) to ensure appropriate personal protection is utilized to safeguard workeragainst hazardous chemical exposure working inside the envelop. For testing the fume hoodspersonnel must wear at a minimum gloves and goggles follow the “Appendix A” algorithm.

4. Facilities personnel will be responsible to test the fume hood prior to servicing; conducting a PhTest and a VOC Test. See Note: on appropriate test procedure indicators on page 3.

5. Facilities personnel will proceed with servicing if the test fall within normal range, if not Facilitiespersonnel will contact the Building User that the fume hood needs to be cleaned again.

6. Facilities personnel will shut off and lock-out and tag-out fume hood prior to providing services.

7. Upon completion of equipment servicing the Facilities personnel will contact supervisor to submitwork order closure. If air flow has been adjusted Facilities personnel must call EH&S 2-5856 sothey can conduct a fume hood performance test. Facilities personnel completing theservicing should write the on the work order number, repair date and their initials on the testtag located on the fume hood. On the work order completion notification write the velocitytest and smoke test results.

All air flow velocities must fall in the range of 80 to 150 FPM (feet per minute) and forradioactive hoods 125 to 150 FPM.

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Working Inside Fume Hood Duct Work Envelop /Drain System/Working Outside FumeHood Envelop

1. Minor Repairs will receive a work order indicating the need for fume hood servicing.

2. Facilities servicing personnel will follow the guidelines provided by Environmental Health andSafety (Appendix A) to ensure appropriate personal protection is utilized to safeguard workeragainst hazardous chemical exposure working inside the envelop. For testing the fume hoodspersonnel must wear at a minimum gloves and goggles follow “Appendix A” algorithm.

3. Facilities personnel will be responsible to test the area prior to servicing; conducting a VOCTest. See Note: on appropriate test procedure indicators located at the bottom of this page.

4. Facilities personnel will shut off and lock-out and tag-out fume hood prior to providingservicing.

5. Upon completion of equipment servicing the Facilities personnel will contact supervisor tosubmit work order closure. If air flow has been adjusted Facilities personnel must call EH&S 2-5856 so they can conduct a fume hood performance test. Facilities personnel completingthe servicing should write the work order number, repair date and their initials on thetest tag located on the fume hood. On the work order completion notification write thevelocity test and smoke test results.

All air flow velocities must fall in the range of 80 to 150 FPM (feet per minute) and forradioactive hoods 125 to 150 FPM.

Test Procedure Indicators

Ph Test: Range

Neutral 7Acidic less than 7Alkaline greater than 7

If the PH is between 5-9 the hood would not need to be recleaned.

VOC-Volatile Organic Chemical: Range

Above Zero to 50 ppm (parts per million) - Follow Appendix A Alogrithm for PPE50 to 100 ppm (parts per million) - Contact the Lab Director/Division Safety Director100 ppm and above (parts per million) - Contact EH&S/Division Safety Director

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APPENDIX A Fume Hood Maintenance work inside or outside the fume hood envelope.

Outside the envelope

Inside the envelope

Safety goggles/hand

protection

Will Exhaust impact the worker?

What body part(s) will be inside?

Arms And/Or Hands

Body Head

Hand Protection (2 pairs of nitrile gloves.) Gauntlet protection.

Is there liquid on surfaces?

Is there measurable VOC’s or other vapors present?

No

No No No

Yes

Yes Yes Yes

Will exhaust impact the worker?

Tyvek (high density polyethylene) coveralls

Coated chemical coveralls with sealed seams

No respirator No respirator

Negative APR Use combination

organic/inorganic Cartridge Filter

SCBA

Negative APR Use combination

organic/inorganic Cartridge Filter

Safety goggles/hand

protection