Bloodborne Pathogens

• Biological Safety Training • Prepared by: Atef El-Gendy, PhD

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)

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 

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    

Which Substances Do Not Transmit Bloodborne Disease?

• feces • nasal secretions • sputum • sweat • tears • vomitus • urine • saliva (very low risk for transmitting Hepatitis,

HIV)

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. 

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.

Biological Safety Cabinets

Types of Biological Safety Cabinets

• Biological safety

cabinets

– Class I

– Class II

– Class III

Class I Biological safety cabinets

– Open fronted

– Negative-pressure ventilated

cabinet

– Provides only worker protection

NOTNOT product protection

Ambient Air

Contaminated Air

Class II Biological safety cabinets- Negative-pressure ventilated cabinet

– Provides HEPA-filtered, recirculated

airflow within the cabinet

– Exhaust air is HEPA-filtered

– ProvidesProvides 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

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

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

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

Safe work habits in a Class II BSC

The front and back grilles should not be blocked with equipment, notes, supplies

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

Safe work habits in a Class II BSC

Use a smaller biohazard bag in the cabinet

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

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