Table 2.

Description of Biosafety Levels (BSL) and Physical Containment (PC) facility requirements^14,26

	BSL-1/PC-1	BSL-2/PC-2	BSL-3/PC-3	BSL-4/PC-4
Description	BSL-1 laboratories that are designated a PC-1 facility are used for work conducted on microorganisms and toxins not known to cause disease in healthy adults	BSL-2 laboratories that are designated a PC-2 facility are used for work conducted on microorganisms and toxins that pose a moderate risk to staff and the environment	BSL-3 laboratories that are designated a PC-3 facility are used for work conducted on microorganisms and toxins that can be transmitted by air and cause potentially lethal infection through respiratory transmission	BSL-4 laboratories that are designated a PC-4 facility are used for work conducted on microorganisms and toxins that pose a high risk of aerosol-transmitted laboratory infections with no vaccine or therapy
Laboratory practices	•Standard Microbiological Practices are followed	•Access to laboratory is restricted when work is being conducted	•Laboratory access is always restricted and controlled	•Laboratory staff receive immunisations for microbes they work with (recommended)
	•Work can be performed on an open bench or table		•Laboratory access required significant training and carefully controlled	•Change clothing before entering
				•Shower upon exiting
				•Decontaminate all materials before exiting
Safety equipment	•No special equipment required	•Appropriate PPE (lab coats and gloves) must be worn	•Appropriate PPE (lab coats, gloves and eye protection) must be worn	•All work is performed within a Class III BSC or by wearing a full body, positive pressure, air supplied suit
	•PPE (lab coats, gloves, eye protection) worn as needed	•Eye protection and face shield worn as needed.	•Respirators worn as required
		•Procedures that produce aerosols or splashed are performed within a Class I or Class II biological safety cabinet (BSC) (recommended)	•All work with biological agents must be performed in a Class I or Class II BSC
		•An autoclave or alternate method of contamination is available for decontamination of laboratory waste
Facility construction	•No special facility design required	•Hand and eye washing sink stations readily available	•Hands-free sink accessible near exit	•Laboratory is an isolated and restricted zone
	•Easily cleaned surfaces that can endure the basic chemicals used in the laboratory		•Exhaust air cannot be recirculated and must use ‘directional’ air flow to ensure that air flows from non-laboratory areas into laboratory areas	•Dedicated supply and exhaust air
	•A sink for handwashing must be accessible		•Two self-closing doors and sealed windows