This document discusses bloodborne pathogens and safety procedures for working with potentially infectious materials. It defines bloodborne pathogens as microorganisms present in human blood that can cause disease, such as HIV and hepatitis B. It describes exposure incidents that can lead to infection and lists body fluids that may transmit bloodborne diseases. The document provides guidance on first aid after an exposure, use of personal protective equipment, types of biological safety cabinets, and safe work practices within biological safety cabinets to prevent exposure to pathogens.

1. Bloodborne Pathogens
• Biological Safety Training
• Prepared by: Atef El-Gendy, PhD

2. Bloodborne pathogens
• OSHA* Definitions
• "Blood" means human blood, human blood
components, and products made from human
blood.
•
"Bloodborne pathogens" means pathogenic
microorganisms that are present in human blood
and can cause disease in humans. These
pathogens include, but are not limited to, hepatitis
B virus (HBV) and human immunodeficiency virus
(HIV).
• *(The Occupational Safety and Health Administration)

3. Bloodborne Exposure FAQ
How Do I Know if I Have Had a Bloodborne
Exposure?
• An exposure incident occurs when human
blood or other potentially infectious materials
enter your body by:
• a splash to the eye, mouth, or other mucous
membrane
• Contamination of non-intact (broken) skin
• A puncture or cut with a sharp instrument

4. Which Substances Might Transmit
Bloodborne Disease?
• Blood or any body fluid or tissue containing
blood
• amniotic, cerebrospinal, pericardial,
peritoneal, pleural, and synovial fluids
• semen
• vaginal secretions
• human organs and unfixed tissues
• breast milk

5. Which Substances Do Not Transmit
Bloodborne Disease?
• feces
• nasal secretions
• sputum
• sweat
• tears
• vomitus
• urine
• saliva (very low risk for transmitting Hepatitis,
HIV)

6. What Should I Do?
• Provide immediate first aid:
• go to nearest sink and scrub & bleed puncture or cut
wounds
• Mechanical scrubbing with soap & water may prevent
virus from entering tissues.
• Washing eyes with water or normal saline will aid the
tears in flushing the virus away.
• Mucous membranes of nose & mouth should be
flushed with water if exposed to body substances.
• Notify your supervisor or employer as soon as
possible.

7. Personal Protective Equipment (PPE)
• PPE will be chosen based on the anticipated
exposure to blood or other potentially infectious
materials. The PPE will be considered appropriate
only if it does not permit blood or other potentially
infectious materials to pass through or reach the
employees’ clothing, skin, eyes, mouth, or other
mucous membranes under normal conditions of use
and for the duration of time, which the protective
equipment will be used.

8. Biological Safety Cabinets

9. Types of Biological Safety Cabinets
• Biological safety
cabinets
– Class I
– Class II
– Class III

10. Class I Biological safety cabinets
– Open fronted
– Negative-pressure ventilated
cabinet
– Provides only worker protection
NOT product protection
Ambient Air
Contaminated Air

11. Class II Biological safety cabinets
- Negative-pressure ventilated cabinet
– Provides HEPA-filtered, recirculated
airflow within the cabinet
– Exhaust air is HEPA-filtered
– Provides personnel and product protection
• Types of Class II BSCs
– Class II A: HEPA filtered air is discharged
into the room
– Class II B: HEPA filtered air is discharged
out of the room
– Class II A/B: Can be used either way.
Contaminated Air
HEPA Filtered Air
Ambient Air

12. Class III BSC
1. Ventilated cabinet - totally enclosed
2. Gas tight construction
3. Operations are conducted through
attached rubber gloves.
4. Both supply and exhaust air are
HEPA-filtered
5. Provides both personnel and product
protection
Ambient Air
Contaminated Air
HEPA Filtered Air
HEPA Filter

13. Safe work habits in a Class II BSC
– Laboratory coats and latex gloves should
always be used
– Adjust the stool height so that your face is
above the front opening

14. Safe work habits in a Class II BSC
– The cabinet blower should be operated at
least 3 to 5 minutes before you begin work
– Manipulation of materials should be
delayed for about 1 minute after placing
your hands and arms inside the cabinet
– All manipulations should be at least 10 cm
from the front grille

15. Safe work habits in a Class II BSC
The front and back grilles should not
be blocked with equipment, notes,
supplies

16. Safe work habits in a Class II BSC
• Materials or equipment placed inside the
cabinet can disrupt airflow – don’t do this!
• Frequent movement of your arms in and out
of the cabinet will disrupt the integrity of the
air barrier

17. Safe work habits in a Class II BSC
Use a smaller biohazard bag in
the cabinet

18. Safe work habits in a Class II BSC
• Open flames (Bunsen burners) are not allowed in a
microbe-free environment of a BSC
• Open flames actually creates turbulence that disrupts
the air flow

19. Decontamination of BSCs
All surfaces should be wiped down with a disinfectant at the
end of any procedure
• 70% Ethanol (ETOH) is the most commonly used
disinfectant
• Many people use 0.05% sodium hypochlorite (Clorox or
bleach) but remember this is very corrosive to stainless
steel, need to wipe off residual bleach with water