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Brief History of Biosafety

National biosafety guidelines evolved from the efforts of the microbiological and biomedical community topromote the use of safe microbiological practices, safety equipment and facility safeguards that will reduceLAIs and protect the public health and environment.

The historical accounts of LAIs raised awareness about the hazards of infectious microorganisms and thehealth risks to laboratory workers who handle them. Many published accounts suggested practices and

methods that might prevent LAIs.

Arnold G. Wedum was the Director of Industrial Health and Safety at the United States Army BiologicalResearch Laboratories, Fort Detrick from 1944 to 1969. His pioneering work in biosafety provided thefoundation for evaluating the risks of handling infectious microorganisms and for recognizing biologicalhazards and developing practices, equipment, and facility safeguards for their control.

From 1974-1976, the evolution of various guidelines published by the CDC and NIH led to the developmentofBiosafety in Microbiological and Biomedical Laboratories(BMBL). Upon its publication in 1984, BMBLquickly became the cornerstone of biosafety practice and policy in the United States, and also worldwide.

Importance of Biosafety

Protects all laboratory personnel and visitors from laboratory-acquired infections;

Maintains the security and integrity of specimens and other research materials;

Provides environmental protection to minimize risks to those outside the laboratory and beyond the confines

of the area Ensures compliance with existing Federal health, safety, and environmental regulations and guidelines.

Biosafety Levels

The regulations outline precautions, special practices, and decontamination procedures for labs that workwith infectious agents.

Based on the degree of hazard posed by these agents, labs are divided into four biosafety levels, andmandated protective practices increase with each level.

o Biosafety Level 1 labs work with the least dangerous agents and require the fewest precautionso Biosafety Level 4 labs have the strictest methods for handling organisms because they deal with

agents that are most dangerous to human health.

*NOT SURE IF THIS NEEDS TO BE INCLUDEDBarriers

Each biosafety level has prescribed barriers to protect against microorganisms.

Primary barriers are physical barriers or personal protective equipment between the lab worker and thepathogen,

o Gloves, masks, or special breathing apparatuses.o Laboratorians use these types of safety equipment to protect themselves directly when working

with organisms.

Secondary barriers are structural aspects of the laboratory itself that make the working environment saferagainst the risk of infection;

o Sinks for handwashing, special containment areas for working directly with organisms, and specialair ventilation patterns designed to prevent contamination of other rooms and other workers in thebuilding.

Universal Precautions

Universal precautions include hand hygiene, use of PPE (gloves, gown, masks, eye protection, and faceshields), and safe injection practices.

Universal precautions also require that all equipment or items likely to have been contaminated withinfectious fluids are handled in a manner that prevents transmission of any infectious agents.

Special circumstances such as the decontamination of methamphetamine labs may require additionalprecautions such as protective clothing and special site decontamination.

Biosafety Level 1I. Hazard Levels

a. Low Risk: Agents pose no threat to human health; that is, they are not known to cause disease inhealthy adults.

i. Examples: Bacillus subtilis, Naegleria gruberi, infectious canine hepatitis virus, and non-pathogenic E. colispecies (see Figure 1).

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II. Standard Microbiological Practices

a. Access to laboratory does not have to be restricted. However, doors cannot be propped open.b. Biohazard signage is not requiredc. Perform all procedures to minimize the creation of splashes and/or aerosolsd. Eating, drinking, smoking, handling contact lenses, applying cosmetics, and storing food for human

consumption is not permitted in laboratory areas.

e. Safe handling practices of contaminated sharps (e.g. needles, blades, glass)i. Needles must not be bent, sheared, broken, recapped, removed from disposable syringes,or otherwise manipulated by hand before disposal.

ii. Disposable sharps must be carefully placed in puncture-resistant containers for sharpsdisposal

iii. Non-disposable sharps must be placed in a hard walled container for decontamination,preferably by autoclaving.

iv. Broken glassware must be removed using a brush and dustpan, tongs, or forceps.v. Plastic ware should be substituted for glassware whenever possible.

f. Decontaminate all cultures, stocks, and other potentially infectious materials before disposal usingan effective method.

g. Decontamination of work surfaces daily, after finishing work and following spills.h. Pipett using a mechanical device no mouth pipetting.i. Handwashing is required after working with potentially hazardous materials and before leaving the

laboratory.

j. Trainingi. The laboratory supervisor must ensure that laboratory personnel receive appropriate

training regarding their duties, the necessary precautions to prevent exposures, andexposure evaluation procedures.

III. Safety Equipmenta. Special containment devices or equipment, such as BSCs, are not generally required.b. Use of laboratory coats recommendedc. Gloves, eye protection, and HEPA-filtered vacuum lines are required

IV. Laboratory Facilitiesa. Negative pressure ventilation. No recirculation or exhaust air to other areas of the building is

permitted.b. Open bench top sink is required for handwashingc. Eyewash station recommended. However, use of hazardous chemicals may change this to a

requirement.d. A door is required for access control

e. Laboratory design should allow the facility to be easily cleaned and decontaminated. Carpets andrugs are not appropriate.

f. Laboratory furniture must be capable of supporting anticipated loads and uses.i. Bench tops must be impervious to water and resistant to heat, organic solvents, acids,

alkalis, and other chemicals.ii. Chairs used in laboratory work must be covered with a non-porous material that can be

easily cleaned and decontaminated with appropriate disinfectant.g. Spaces between benches, cabinets, and equipment should be accessible for cleaning.

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References:

US Department of Health and Human Services, Centers for Disease Control and Prevention and National Institutesof Health. Biosafety in Microbiological and Biomedical Laboratories. 5th ed. Washington, DC: US GovernmentPrinting Office; 2007. Retrieved fromhttp://www.cdc.gov/od/ohs/ biosfty/bmbl5/bmbl5toc.htm.

North Carolina Center for Public Health Preparedness (2008) FOCUS Volume 5, Issue 1: Laboratory BiosafetyLevels. Retrieved from University of North Carolina School of Public Health website: cphp.sph.unc.edu/.../5-1BiosafetyLevels_slide...

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