Changing Fluorescent Light Tubes in Chemical Fume Hoods
Routine service of laboratory fume hoods includes the periodic changing of burned out fluorescent light tubes. Although chemical fume hoods are designed to exhaust hazardous materials away from the lab, some hoods may have small amounts of chemical residue and require special preparation before light tubes can be replaced. The following procedures have been developed to ensure the safety of the facilities personnel as well as to prevent damage to laboratory materials and equipment.
Note: Chemical fume hoods should not be confused with Biological Safety Cabinets (BSCs). A separate protocol has been developed for changing spent ultraviolet lamps in BSCs.
Preparation for Work
1. Hazard Determination: Certain hoods may require special considerations due to the use of chemicals with unique hazards (e. g. perchloric acid). Contact EH&S for service activities with these or other "special hazard" types of hoods.
2. Notifications: Follow all notification procedures described in (reference main document)
3. Preparation of the Hood Work Area
- Materials and Equipment
- When bulbs are changed from above the hood: Laboratory personnel should follow all safety precautions and preparatory measures described in the Overview - General Safety Procedures. Lab occupants must ensure all potentially hazardous materials inside the hood are capped and/or secured such that there is no possibility of release during service. Wherever feasible, active experiments should be halted during service. Highly hazardous materials should be removed from the hood altogether during service. In addition, lab personnel must remove any obstructions to the fume hood (items on the floor, etc.) such that a ladder can be placed nearby.
- When bulbs are changed from inside the hood: Lab occupants must remove all potentially hazardous materials, equipment, and experimental apparatus from inside the hood prior to service. In addition, lab personnel must remove any obstructions to the fume hood (items on the floor, etc.) such that a ladder can be placed nearby.
- Cleaning and Decontamination:
- When bulbs are changed from above the hood: Lab occupants should clean and decontaminate the sash and any other parts of the hood that the facilities maintenance operator will reasonably come in contact with during the activity.
- When bulbs are changed from inside the hood: Lab occupants should clean and decontaminate all hood surfaces prior to any work by facilities personnel.
- Special Procedures:
- Radioisotope hoods: Lab personnel must survey radioisotope hoods prior to changing fluorescent light tubes. If contamination is found, lab personnel must clean the work surface until acceptable contamination levels are achieved (See Section 9.6 Radiocontamination Limits of the Radiation Safety Manual). Any surfaces with fixed contamination must be covered and shielded to background levels. Any coverings used, (ie..plexiglass) must be secured so that the material cannot move.
- Special hazard hoods: Certain hoods may require special considerations due to the use of chemicals with unique hazards (e. g. perchloric acid). Contact EH&S for service activities with these types of hoods.
- Biological materials and animals: Hood surfaces must be wiped down with a disinfectant if biological materials are used. For Biosafety Level 2 (BL-2) laboratories, all Bl-2 materials must be placed into storage before entering the laboratory.
- Other: Lab occupants must mitigate the hazards of any other materials used in their hood that requires special handling. EH&S can be contacted for assistance in extenuating circumstances.
4. Preparation of Work Area - Other Considerations
- Ensure the ladder is in good working order, secure, and of sufficient height.
- Turn off the power to the light source prior to service.
5. Personal Protective Equipment
- Wear recommended protective apparel. Latex or nitrile gloves are adequate for most applications. If the work creates dust (e.g. from disturbing parts of the hood upon which dust/debris has settled) wear safety glasses with side shields.
Doing the Work
1. Ergonomics
- Be aware of body movements and take care not to sustain awkward postures. When working inside or above fume hoods it may be necessary to move the body in awkward ways. These movements may contribute to musculoskeletal injury. To the extent feasible, try to adjust the ladder or other work surfaces to minimize any sustained awkward or forceful movements for the duration of the service.
2. Lighting
- Use a flashlight when working in dark corners. Pipes or other items near the ceiling often shadow the areas above fume hoods and the darkness may contribute to an accident.
Completion of Activities
1. Clean up work site
- Wash down the area if appropriate. In general, only wet cleaning methods should be used.
- Gather up tarps or drop cloths and clean up area.
2. Disposal
- Fluorescent light tubes contain small quantities of mercury and must be treated as Universal Waste. Facilities personnel should take care to remove all spent fluorescent tubes from the lab and place them in the appropriate universal waste accumulation area.
3. Hygiene
- Wash hands after service activities.
