Spills can happen in all laboratories irrespective of their size or sophistication. Spill Management is often overlooked when considering laboratory safety but spills expose laboratory workers to hazards like any other laboratory operations.
The topic was touched upon briefly in the earlier article General Guidelines for laboratory safety. In the present article general guidelines are offered for handling of some uncommon spills such as poisonous chemicals, mercury, radioactive materials and microbiological substances.
Poisonous materials can enter the human system either through skin or through inhalation. Evacuate the laboratory after stopping ongoing experiments. The person attending to the spill should use protective gloves and masks during cleanup operations. After cleaning the spill remember to dispose of the gloves and facemask along with the material removed.
Extinguish all naked flames and switch off hot plates and electrical equipments which are potential sources of sparks. Surround the spill with absorbent pads and allow the pads to soak the liquid completely. Using tongs place the absorbing pads in a polythene bag and seal the bag. Wipe the area with that detergent and mop with water.
Mercury does not pose immediate harm but vapour inhalation can pose health hazards over time. Small droplets can penetrate cracks and crevices on the laboratory bench and continue emitting vapour Use an eyedropper to remove such drops or a special mercury vacuum cleaner to collect the droplets in a disposal container. Never use a regular vacuum cleaner. Never walk through a mercury spilled area. Dispose shoes into a sealed bag if you have accidentally walked through the mercury spilled floor.
Sulphur powder can be sprinkled over minute remaining droplets, spray water and using a scrapper and had damp sponge collect into a bag along with the scrapper dispose the bag.
Exposure to radioactivity can pose long-term hazards. In case of isotope spills first of all workers should be evacuated from the contaminated area and radiation safety officer should be informed. Isolate the potentially affected persons in quarantine area and permit them to leave only after they have been cleared of radioactive contamination. Before attempting to clean use protective clothing, gloves and shoe covers. Cover the affected area with absorbent pads, work inside the spill and dispose the pads into a radioactive disposal waste container. The contaminated gloves and other disposable materials should also be disposed off. At the end of cleaning monitor the area, hands, clothing and shoes with a radioactive monitor.
Spills in microbiological laboratories can pose varying degrees of health hazards depending upon scale of spill and the spill area.
Spills inside Bio safety cabinets pose less hazards as harmful aerosols are also contained and swept away by cabinet air stream. The spill can be conveniently cleaned with a suitable disinfectant. Gloves used for cleaning the cabinet should be discarded off. Spills outside the Bio safety cabinet need greater attention because of potential exposure hazards. Spills should be covered with a disinfectant or material which liberates hypochlorite. After about 10 min mop the area and dispose all the contaminated material for sterilisation by autoclaving. Sharp or broken objects should also be subject to sterilisation separately before discarding in separate sharps disposable containers.
Please feel free to offer your suggestions and share your experiences.