Airtech Laboratory and Bio-safety level facilities According to WHO Bio-Safety BSL1-4 & Animal BSL1-4 Guidelines, the house should be independent and detached unit. If it adjoins a laboratory, the design should provide for its isolation from public parts of the laboratory should such need rise, and its decontamination and disinfestations.. http://www.airtech.com.sg/product/productdetails/laboratory-and-bio-safety