Laboratory safety

Many laboratories contain significant risks, and the prevention of laboratory accidents requires great care and constant vigilance. Examples of risk factors include high voltages, high and low pressures and temperatures, corrosive and toxic chemicals, and biohazards including infective organisms and their toxins.

Measures to protect against laboratory accidents include safety training and enforcement of laboratory safety policies, safety review of experimental designs, the use of personal protective equipment, and the use of the buddy system for particularly risky operations.

In most countries, laboratory work is subject by health and safety legislation. In some cases, laboratory activities can also present environmental health risks, for example, the accidental or deliberate discharge of toxic or infective material from the laboratory into the environment.

Chemical hazards

Hazardous chemicals present physical and/or health threats to workers in clinical, industrial, and academic laboratories. Laboratory chemicals include cancer-causing agents (carcinogens), toxins (e.g., those affecting the liver, kidney, and nervous system), irritants, corrosives, sensitizers, as well as agents that act on the blood system or damage the lungs, skin, eyes, or mucous membranes.[1]

Biological hazards

Biohazard symbol (black and yellow)

Biological agents and biological toxins

Many laboratory workers encounter daily exposure to biological hazards. These hazards are present in various sources throughout the laboratory such as blood and body fluids, culture specimens, body tissue and cadavers, and laboratory animals, as well as other workers.

These are federally regulated biological agents (e.g., viruses, bacteria, fungi, and prions) and toxins that have the potential to pose a severe threat to public health and safety, to animal or plant health, or to animal or plant products.[2][3]

  1. Anthrax - Anthrax is an acute infectious disease caused by a spore-forming bacterium called Bacillus anthracis.
  2. Avian Flu - Avian influenza is caused by Influenza A viruses.
  3. Botulism - Cases of botulism are usually associated with consumption of preserved foods.
  4. Foodborne Disease - Foodborne illnesses are caused by viruses, bacteria, parasites, toxins, metals, and prions (microscopic protein particles). Symptoms range from mild gastroenteritis to life-threatening neurologic, hepatic and renal syndromes.
  5. Hantavirus - Hantaviruses are transmitted to humans from the dried droppings, urine, or saliva of mice and rats.
  6. Legionnaires’ Disease - Legionnaires’ disease is a bacterial disease commonly associated with water-based aerosols.
  7. Molds and Fungi - Molds and fungi produce and release millions of spores small enough to be air, water , or insect-borne which may have negative effects on human health including, allergic reactions, asthma, and other respiratory problems.
  8. Plague - The World Health Organization reports 1,000 to 3,000 cases of plague every year. A bioterrorist release of plague could result in a rapid spread of the pneumonic form of the disease, which could have devastating consequences.
  9. Ricin - Ricin is one of the most toxic and easily produced plant toxins. It has been used in the past as a bioterrorist weapon and remains a serious threat.
  10. Smallpox - Smallpox is a highly contagious disease unique to humans. It is estimated that no more than 20 percent of the population has any immunity from previous vaccination.
  11. Tularemia - Tularemia is also known as "rabbit fever" or "deer fly fever" and is extremely infectious. Relatively few bacteria are required to cause the disease, which is why it is an attractive weapon for use in bioterrorism.

Physical hazards and others

Besides exposure to chemicals and biological agents, laboratory workers can also be exposed to a number of physical hazards. Some of the common physical hazards that they may encounter include the following: ergonomic, ionizing radiation, non-ionizing radiation and noise hazards.

Ergonomic Hazards

Laboratory workers are at risk for repetitive motion injuries during routine laboratory procedures such as pipetting, working at microscopes, operating microtomes, using cell counters and keyboarding at computer workstations. Repetitive motion injuries develop over time and occur when muscles and joints are stressed, tendons are inflamed, nerves are pinched and the flow of blood is restricted. Standing and working in awkward positions in front of laboratory hoods/biological safety cabinets can also present ergonomic problems.[4][5]

Ionizing Radiation

Danger radiation zone warning sign

Ionizing radiation sources are found in a wide range of occupational settings, including laboratories. These radiation sources can pose a considerable health risk to affected workers if not properly controlled. Any laboratory possessing or using radioactive isotopes must be licensed by the Nuclear Regulatory Commission (NRC) and/or by a state agency that has been approved by the NRC, 10 CFR 31.11 and 10 CFR 35.12.[6]

The fundamental objectives of radiation protection measures are:

  1. to limit entry of radionuclides into the human body (via ingestion, inhalation, absorption, or through open wounds) to quantities as low as reasonably achievable (ALARA) and always within the established limits;
  1. to limit exposure to external radiation to levels that are within established dose limits and as far below these limits as is reasonably achievable.

Safety hazards

Autoclaves and sterilizers

Workers should be trained to recognize the potential for exposure to burns or cuts that can occur from handling or sorting hot sterilized items or sharp instruments when removing them from autoclaves/sterilizers or from steam lines that service the autoclaves.[7]

Centrifuges

Centrifuges, due to the high speed at which they operate, have great potential for injuring users if not operated properly. Unbalanced centrifuge rotors can result in injury, even death. Sample container breakage can generate aerosols that may be harmful if inhaled. The majority of all centrifuge accidents are the result of user error.

Compressed gases

Compressed gas cylinders.mapp and oxygen.triddle

Laboratory standard for compressed gas

  1. Is a gas or mixture of gases in a container having an absolute pressure exceeding 40 pounds per square inch (psi) at 70 °F (21.1 °C); or[8]
  2. Is a gas or mixture of gases having an absolute pressure exceeding 104 psi at 130 °F (54.4 °C) regardless of the pressure at 70 °F (21.1 °C); or[8]
  3. Is a liquid having a vapor pressure exceeding 40 psi at 100 °F (37.8 °C) as determined by ASTM (American Society for Testing and Materials)

Within laboratories, compressed gases are usually supplied either through fixed piped gas systems or individual cylinders of gases. Compressed gases can be toxic, flammable, oxidizing, corrosive, or inert. Leakage of any of these gases can be hazardous.[9]

Store, handle, and use compressed gases

Cryogens and dry ice

Cryogens, substances used to produce very low temperatures [below -153 °C (-243 °F)], such as liquid nitrogen (LN2) which has a boiling point of -196 °C (-321 °F), are commonly used in laboratories.[11]

Although not a cryogen, solid carbon dioxide or dry ice which converts directly to carbon dioxide gas at -78 °C (-109 °F) is also often used in laboratories. Shipments packed with dry ice, samples preserved with liquid nitrogen, and in some cases, techniques that use cryogenic liquids, such as cryogenic grinding of samples, present potential hazards in the laboratory.[11]

Hand protection is required to guard against the hazard of touching cold surfaces. It is recommended that Cryogen Safety Gloves be used by the worker.[12][13]

Eye protection is required at all times when working with cryogenic fluids. When pouring a cryogen, working with a wide-mouth Dewar flask or around the exhaust of cold boil-off gas, use of a full face shield is recommended.[14]

Personal protective equipments

Personal protective equipment or PPE are equipments worn to prevent against exposure of hazardous substances.[15] Although, PPE does not eliminate the risks of hazards but it helps protect the user from the exposure.[16] To make a workplace safer, it should provide instructions and training of how to use and choose proper PPE in different situations.[15]

Nitrile gloves

PPE includes:

Electrical

In the laboratory, there is the potential for workers to be exposed to electrical hazards including electric shock, electrocutions, fires and explosions. Damaged electrical cords can lead to possible shocks or electrocutions. A flexible electrical cord may be damaged by door or window edges, by staples and fastenings, by equipment rolling over it, or simply by aging.[18]

The potential for possible electrocution or electric shock or contact with electrical hazards can result from a number of factors, including the following:

Fire

Fire

Fire is the most common serious hazard that one faces in a typical laboratory. While proper procedures and training can minimize the chances of an accidental fire, laboratory workers should still be prepared to deal with a fire emergency should it occur. In dealing with a laboratory fire, all containers of infectious materials should be placed into autoclaves, incubators, refrigerators, or freezers for containment.[20]

Small bench-top fires in laboratory spaces are not uncommon. Large laboratory fires are rare. However, the risk of severe injury or death is significant because fuel load and hazard levels in labs are typically very high. Laboratories, especially those using solvents in any quantity, have the potential for flash fires, explosion, rapid spread of fire, and high toxicity of products of combustion (heat, smoke, and flame)

Fire blanket

See also

References

  1. ↑ "Chapter 8 - Chemical Hazards". sp.ehs.cornell.edu. Retrieved 2016-04-07.
  2. ↑ "Biological Agents and Biological Toxins". Occupational Safety and Health Administration. Retrieved 4 February 2015.
  3. ↑ "An additional OSHA Safety and Health Topics page on Pandemic Influenza has been added in response to the 2009 H1N1 influenza pandemic.". OSHA. Retrieved 4 February 2015.
  4. ↑ "Laboratory Safety – Ergonomics for the Prevention of Musculoskeletal Disorders" (PDF). OSHA. Retrieved 25 October 2015.
  5. ↑ Darragh AR, Harrison H, Kenny S. Effect of ergonomics intervention on workstations of microscope workers. American Journal of Occupational Therapy. 2008. 62:61-69.
  6. ↑ "Ionizing Radiation". Retrieved 25 October 2015.
  7. ↑ "An OSHA QuickFacts entitled Laboratory Safety – Autoclaves/Sterilizers has been developed to sup-plement this section and is available online at osha.gov.". Retrieved 6 February 2015.
  8. 1 2
  9. ↑ "About Compressed gases".
  10. 1 2 3 "Store, handle, and use compressed gases" (PDF).
  11. 1 2 "Safety Library Cryogens And DryIce". Retrieved 6 February 2015.
  12. ↑ "Safetygrams". www.airproducts.com. Retrieved 2016-04-07.
  13. ↑ "Stanford University: SLAC Environment, Safety, and Health Manual, Chapter 36" (PDF). Stanford University. Retrieved 6 February 2015.
  14. 1 2 3 4 "ES&H Manual, Chapter 29: Safe Handling of cryogenic liquids". Lawrence Berkeley National Laboratory. Retrieved 6 February 2015.
  15. 1 2 "Personal Protective Equipment (PPE)". www.hse.gov.uk. Retrieved 2015-06-22.
  16. ↑ "Laboratory Safety PPE | Yale Environmental Health and Safety". ehs.yale.edu. Retrieved 2015-06-22.
  17. 1 2 "http://www.nps.gov/museum/publications/conserveogram/01-12.pdf" (PDF). www.nps.gov. Retrieved 2015-06-29. External link in |title= (help)
  18. ↑ "Electrical Hazards" (PDF). OSHA. Retrieved 6 February 2015.
  19. 1 2 3 https://www.lanl.gov/safety/electrical/docs/elec_hazard_awareness_study_guide.pdf
  20. ↑ "Fire Hazards control". Retrieved 6 February 2015.
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