Centrifuge safety

Equipment is considered the primary barrier for protection of the employees. Items such as biosafety cabinets, safety centrifuges, enclosed containers, impervious work surfaces, autoclaves, foot-operated sinks, and other equipment specifically designed to prevent direct contact with infectious organisms or with aerosols must be available. Personal protective equipment can also be considered as an effective secondary barrier if engineering controls are not sufficient. These latter items can include, at minimum, a lab coat or wrap-around gown, possibly gloves, masks, or respirators, goggles, and head and foot covers. 

Laboratory Safety Centrifuges Quick Facts (OSHA 3406— 2011). 

Safety Equipment Enclosed containers, biological safety cabinets, and personal protection equipment are the main kinds of safety equipment. The primary roles are containment and barriers. Safety containers prevent the release of unsafe substances during normal activities and operations. An example is a safety centrifuge cup. 

The separation of cells from the culture media or fermentation broth is the first step in a bioproduct recovery sequence. Whereas centrifugation is common for recombinant bacterial cells (see Centrifugal separation), the final removal of CHO cells utilizes sterile-filtration techniques. Safety concerns with respect to contamination of the product with CHO cells were addressed by confirming the absence of cells in the product, and their relative noninfectivity with respect to immune competent rodents injected with a large number of CHO cells. 

A good discussion of centrifuge safety design features and operating practices is found in an IChemE publication (1987). 

Rupture disk, 455 Safety relief valves, 454, 467, 481 Specifications, centrifugal pumps, 209 Spray nozzle particle size, 225 Standards and Codes, 31, 32, 33 Static electricity, 536 Static mixing, 332 Applications, 336 Calculations, 337, 338 Materials of construction, 337 Principles of operation, 335 Type of equipment 334-338... 

Large capacity balances, centrifuges, and similar equipment are generally placed on a separate counter away from the benches. The size of this counter must be carefully estimated. There must also be room for equipment and supplies kept in the laboratory as opposed to the stockroom. Of course, space must also be allowed for a safety shower and eyewash station. 

Bouin s solution is one of the traditional ways to harden cell pellet. Some cytologists believe it provides the best cellular details, especially nuclear features in cell blocks.28 The major steps are (1) After centrifugation, fix the cell pellet with Bouin s solution. (2) After 2h, discard the solution. (3) Remove the hardened cell pellet from the tube, wrap it with lens paper, and transfer it into a cassette for further processing. We have been using this method for many years. In our experience, most of the time, ICC results are consistent with IHC from the surgical specimen. The biggest drawback of this method is the toxicity of Bouin s fixative which creates biohazard and safety issues for the laboratory. We also found cell blocks gave poor fluorescence in situ hybridization (FISH) results after Bouin s fixation. 

System total heads should be estimated as accurately as possible. Safety factors should never be added to these estimated total head values. This is illustrated by Figure 4.8. Suppose that OAi is the correct curve and that the centrifugal pump is required to operate at point A. Let a safety factor be added to the total head values to give a system curve OA2. On the basis of curve OA2, the manufacturer will supply a pump to operate at point A2. However, since the true system curve is OA, the pump will operate at point Ai. Not only is the capacity higher than that specified, but the pump motor may be overloaded. 

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