EM Laboratory Hazards
Lab hazards may appear as an obvious and immediate hazard –e.g. cold burns from liquid nitrogen spills, while other dangers may be less visible. These "hidden dangers" can be just as, or even more, dangerous - e.g. suffocation (due to the depletion of oxygen) by the evaporation of liquid nitrogen.
Other hazards you may encounter in an EM lab include:
- Chemical: These are the major hazards present in a lab and include toxic, corrosive and suspected carcinogenic chemicals. e.g. biological fixatives (glutaraldehyde, osmium tetroxide) are designed to kill cells quickly and they will do the same to your cells. Some samples may also be a chemical hazard.
- Electrical: High voltage is present in electron microscopes and other electrical equipment. Covers afford protection and should not be removed. Liquids of any volume should be used with great caution around electrical equipment.
- Thermal: High or low temperatures e.g. hot plates, dry ice, cryogens (liquid Nitrogen).
- Muscular: This includes strains and ergonomic issues e.g. sitting for long periods at a microscope without adjusting the monitors or chair, may cause muscle strains.
- Mechanical hazards: (moving equipment parts, sharp edges) e.g. razorblades, polishers, saws. Electrical cables or water lines may also present a tripping hazard.
Less common hazards that may be present include:
- Microbiological: Live samples may cause infections, irritations or allergic reactions– these should only be present in labs designed to handle them (PC2 or PC3 laboratories).
- Acoustic: Noisy pumps, equipment and sudden loud noises (e.g. opening of improperly connected or unconnected gas cylinders).
- Radiation: (Uranium stains – used in TEM; and X-rays from EM's.) EM's generate high energy X-rays. However, exposure to these X-rays is practically impossible, due to microscope design. Improper modification of microscopes may cause leaks.
Hazard awareness – the induction process
As with any workplace, individuals should be inducted into the area to familiarize individuals with the local OH&S systems and be made aware of the general hazards in the workplace. This lab induction should contain basic information such as location and use of first aid and spill kits, fire-extinguishers, emergency contacts and procedures. Emergency exits and assembly points should also be explained. Location or sources of MSDS's (Material Safety Data Sheets) are often included. Detailed information on hazards relating to individual processes or equipment may not always be presented in an initial induction. This information is best presented by the expert(s) in that process, usually at the start of training in that process. Often trainers will refer to Standard Operating Procedures or risk assessments to explain these hazards. Workplaces are required to document your understanding of these procedures or the risk assessments, and you are quite often asked to "sign-off" on a document or acknowledge this in some other way such as by passing a quiz.