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SAFETY MANUAL   |   CHAPTER 5

Biological Safety

Good practices, biological safety equipment, personal protective equipment, spill control and biowaste disposal procedures.

Home Safety Manual Chapter 5
CHAPTER 5

Biological Safety

The Indian Institute of Science (IISc), Bangalore, is committed to maintaining the highest standards of safety in teaching, research, and innovation. This Biosafety Manual aims to protect students, researchers, staff, the environment, and the surrounding community from potential biological risks arising from laboratory activities.

The manual outlines key aspects of biosafety, including risk assessment, classification of biological agents, biosafety levels (BSL), use of personal protective equipment (PPE), waste management, emergency response, and incident reporting. It also aligns with national regulatory requirements and best practices to ensure safe and responsible conduct of research.

All personnel working in laboratories involving biological materials are required to understand and adhere to the guidelines provided in this manual.

5.1 Biological Safety

5.1 Good Practices

Table No. 5.1   BSL-1, BSL-2 and BSL-3 Safety Practices
BSL-1
(Low Risk) 		BSL-2
(Moderate Risk) 		BSL-3
(High Risk, Aerosol Transmission)
Live culture
handling
  1. Standard microbiological practices
  2. No eating/drinking in the lab
  3. Wash hands
  4. Surface decontamination is mandatory
  5. Always use pipetting aids. Never mouth pipette.
BSL-1 practices, and additionally:
  1. Only trained personnel can handle BSL2 cultures.
  2. Lab access must be limited.
  3. Documented SOP is required for the storage and transport of cultures.
  4. Documented SOP is required for instruments, waste, sharps, and bio spills.
  5. Infectious materials should be in a durable, leak-proof primary container. The primary container is in a durable, leak-proof secondary container for transport within the facility (e.g., to an incubator or another lab bench).
  6. The secondary container should be decontaminated if there's suspicion of contamination.
  7. Properly label all containers.
  8. Use biosafety cabinets (BSCs) for potentially aerosolized pathogens.
  9. Ensure proper functioning of BSCs and other safety equipment.
  10. Minimize splashes and aerosols.
BSL-2 practices and additionally:
  1. Controlled access with two sets of self-closing doors, often with an anteroom.
  2. All personnel must undergo comprehensive training in BSL-3 practices, procedures, emergency response, and the specific risks associated with the agents being handled.
  3. ALL open manipulations of BSL-3 cultures, and any procedure with these cultures that could generate aerosols or splashes, must be performed inside a certified Class II or Class III Biosafety Cabinet.
  4. Work within the designated safe zone of the BSC, avoiding disruption of the air curtain by rapid arm movements or blocking the grilles.
  5. All culture vessels (flasks, plates, tubes, cryovials) must be robust, leak-proof, and sealed during handling and storage outside of the BSC (e.g., when moving to an incubator or centrifuge).
  6. If using screw-cap tubes, ensure caps are tightly secured. For plates, consider using parafilm or specific sealing mechanisms if there's any risk of aerosolization during transport or incubation.
  7. If mixing cultures, do so gently within the BSC. If vortexing, ensure the tube is tightly capped and consider using a mini-vortexer inside the BSC to limit potential aerosol dispersion.
  8. Maintain a highly accurate and up-to-date inventory of all BSL-3 culture stocks (including strain, date, quantity, location).
Spore-forming
culture handling 		All spore-forming cultures in the above BSL1 laboratory.
  1. Spores (bacterial or fungal) are highly resistant. They can survive many disinfectants, desiccation, and UV radiation. So, they are challenging to eliminate.
  2. Spores are easily aerosolized.
All BSL2 live culture practices, and additionally:
  1. Always work in a BSC for all manipulations. This is non-negotiable for spore-forming agents, even for procedures that might seem low-risk with non-spore formers.
  2. Avoid or minimize procedures that generate aerosols (e.g., vigorous shaking, sonication, pipetting forcefully, rapid opening of containers). If unavoidable, perform extreme caution in the BSC.
  3. Allow aerosols to settle in the BSC for 5-10 minutes after manipulation before removing items.
  4. Immediately after use and after any spills, decontaminate all work surfaces (BSC interior, benchtops) with an effective sporicidal disinfectant, e.g., Chlorine-based disinfectant or Hydrogen peroxide 10-30% with a contact time of 15-20 mins.
  5. All equipment (e.g., pipettors, centrifuges, incubators) that comes into contact with spore material must be decontaminated using sporicidal agents or autoclaved.
  6. Emphasize rigorous hand washing. Consider using an alcohol-based hand rub after washing hands, though soap and water are paramount for spore removal.
  7. Maintain excellent general laboratory cleanliness to prevent accumulation of spores in dust or on surfaces. Use wet methods (e.g., wiping with disinfectant-soaked cloths) instead of dry sweeping/dusting.
  8. Store spore stocks in clearly labelled, robust, and potentially double-contained vials/tubes to prevent accidental breakage and dispersal.
  9. Consider establishing a baseline health status for personnel working with spore-forming agents.
All BSL3 live culture practices:
  1. Use EPA-approved sporicidal disinfectants (e.g., high concentrations of sodium hypochlorite/bleach, hydrogen peroxide, glutaraldehyde, peracetic acid) with 20-30 min contact times.
  2. Avoid the application of disinfectants with the spray method to prevent the formation of aerosols. Pouring disinfectant on the spill covered by a microfibre cloth is sufficient.
  3. All work surfaces must be decontaminated daily and immediately after any spill with a validated sporicidal agent.
  4. All materials and equipment must be decontaminated before removal from the BSC or the BSL-3 facility. This includes wiping down exteriors of tubes, flasks, and pipettes with sporicidal disinfectant before removing them from the BSC.
  5. Use sealed safety cups, safety buckets, or sealed rotors with O-rings. Load and unload tubes and rotors within a BSC. Allow aerosols to settle for at least 10 minutes after a run before opening the centrifuge.
  6. Decontaminate the centrifuge interior and accessories if a tube breakage occurs.
  7. Autoclaving is the preferred method for inactivating spore-forming organisms in solid and liquid waste.
  8. Procedures that create aerosols (e.g., vigorous mixing, sonication, grinding, pipetting) should be minimized or performed with extreme caution within the BSC.
  9. Maintain an accurate and up-to-date inventory of all spore-forming agents.
  10. Consider implementing environmental monitoring (e.g., surface swabbing) to detect the presence of spores in the laboratory, especially after decontamination procedures.
  11. Consider establishing a baseline health status for personnel working with spore-forming agents.
Organisms'
Genetic Materials
Handling Practices
(includes recombinant
DNA (rDNA), synthetic
nucleic acid molecules,
and any cells,
organisms, or viruses
containing such
molecules)
  1. Standard microbiological practices
  2. The risk assessment of the specific genetic material determines the appropriate containment level, e.g., nature of insert, host organism, & vector characteristics
All BSL2 practices and additionally:
  1. Transport all genetic materials within the facility in durable, leak-proof primary containers placed within a secondary, leak-proof container (e.g., a sturdy tray or bucket) to prevent spills.
  2. Avoid public areas during transport if materials are moving outside the immediate lab space.
All BSL3 practices
  1. For work involving indigenous or exotic agents, e.g., Mycobacterium tuberculosis, SARS-CoV-2, HIV, rabies virus, West Nile virus, and various highly pathogenic bacteria and viruses, including their genetic material.
Attenuated
culture handling
  1. Standard microbiological practices
  2. No eating/drinking in the lab
  3. Wash hands
  4. Always use pipetting aids. Never mouth pipette.
Adhere to BSL-2 live cultures handling practices.
  1. Even if attenuated, understand the specific attenuated strain, its parent strain's virulence, any residual pathogenicity, potential for reversion to virulence, and known transmission routes.
  2. Infectious materials should be stored in a lockable freezer or designated laboratory room.
  3. Always handle attenuated BSL-2 cultures diligently.
Adhere to BSL-3 live cultures handling practices.
  1. While its virulence is reduced, "attenuated BSL-3" cultures still possess characteristics that necessitate handling within a BSL-3 facility due to their potential for aerosol transmission and ability to cause severe disease.
  2. Immunocompromised individuals might be susceptible to infection by the attenuated or vaccine strain. Therefore, never compromise on BSL-3 containment measures when handling these agents.
  3. Always handle attenuated BSL-3 cultures diligently.

Chemical Safety Fig 5.1 Work inside the Biosafety Cabinet and prevent contamination
5.1 Good Practices

5.1.1 Hazardous Equipment

  1. The equipment must be properly installed, maintained, and calibrated.
  2. All hazardous equipment must have a senior staff member or student responsible for training, maintenance, and upkeep.
  3. Only trained users can operate the equipment.
  4. Users must read the equipment manual before using and follow the SOP.
5.1 Good Practices

5.1.2 Hot Air Oven

  1. Wear PPE as per the guidelines. Heat-resistant gloves may be required.
  2. Don’t plug the hot air oven into an extension cord.
  3. Don’t overload the hot air oven.
  4. Don’t exceed the operating temperature limits.
  5. Don’t use mercury thermometers to monitor temperatures. They tend to break.
  6. If you have a model with an exposed heating element on the bottom, do not place items on the shelf that can potentially fall onto the heating element.
  7. Never put flammable, combustible, reactive, or corrosive materials inside. High-temperature-intolerant materials can cause fire.
  8. Be cautious of hot surfaces when loading and unloading.
  9. Keep your face, body, and hands away from the escaping heat when opening the machine door.
  10. Residual chemicals may volatilize, causing an inhalation hazard. Clean the equipment to remove residual chemicals before using.
5.1 Good Practices

5.1.3 Biosafety Cabinet

A biosafety cabinet (BSC) should be selected primarily based on the type of protection needed.

  1. Start-Up
    • Wear PPE.
    • To minimize cross-contamination, materials considered “clean” must be at least 150 mm away from aerosol-generating objects.
    • Biohazard collection bags should be inside the cabinet.
    • Use absorbent pads on the work surface to minimize splatter or aerosol in case of a spillage.
    • Do not obstruct the front or back air grilles.
  2. Operations
    • Minimize movements to avoid disrupting cabinet airflow.
    • Please do not use a gas flame, as it interferes with airflow.
  3. Shut Down
    • Seal biohazard bags.
    • Decontaminate the items before removing them from the cabinet.
    • Decontaminate the surface of the cabinet inner sidewalls, back wall, work surface, drain pan, and the inner side of the sliding sash/hinged window.
5.1 Good Practices

5.1.4 Incubator

  1. The incubator should be switched off when not in use.
  2. Do not overload the incubator.
  3. Disinfect the incubator every 6 months or in case of a spill. Before disinfection, disconnect the incubator plug from the main socket.
  4. Use 70% ethanol to clean metallic surfaces (i.e., racks, floors, walls, and doors) of the incubator.
  5. The temperature of the incubator must be calibrated.
  6. Re-calibration is mandatory if the incubator has been repaired, cleaned, or restarted after a power failure.
Chemical Safety Fig 5.2 Incubator parts and cleaning points
5.1 Good Practices

5.1.5 Autoclave

  1. An autoclave sterilizes items using heat and pressurized steam. Laboratories commonly use autoclaves to sterilize glassware, non-electronic instruments, media and solutions, and biohazardous waste.
  2. Record cycle information on the autoclave log sheet or logbook.
  3. PPE
    • Always wear the minimum PPE when using an autoclave. Refer to PPE Guidelines.
    • To prevent burns from heat and steam, use long heat-resistant gloves.
Chemical Safety Fig 5.3 Autoclave parts and safe loading of biohazard bags
  1. Pre-Inspection
    • Inspect the door gasket (seal) for cracks or bulges. The gasket should be smooth and pliable.
    • Clean the drain screen of debris.
    • Inspect for spills or debris inside the autoclave.
    • Contact the equipment in charge if you notice any problems. Do not use the autoclave.
  2. Autoclaveable Items
    • Do not autoclave flammable, combustible, reactive, corrosive, toxic, or radioactive materials.
    • All plastics must be autoclavable.
    • Inspect glassware for cracks. Do not autoclave cracked or compromised glassware.
    • Loosen the caps of liquid-filled vials or cover them with foil. This allows the steam to penetrate the vial and prevent an explosion.
    • Bagged items should be tied or taped loosely. Steam must be able to penetrate the bag.
  3. Load
    • Place items in an autoclave tub on a rack. Never place items directly on the autoclave bottom or floor.
    • Always use secondary containment, just in case of spillover.
    • Ensure that the autoclave has reached sufficient pressure to start a cycle.
    • Do not overload the autoclave. Allow adequate space between items for steam.
    • Check the water level.
    • Make an entry in the logbook.
  4. Unload
    • Never open an autoclave door during a cycle! If necessary, abort the cycle and wait until the chamber depressurises.
    • If the cycle fails, notify the equipment in charge. Items may not be sufficiently decontaminated if the cycle is not completed.
    • Before unloading, verify that the chamber temperature has dropped and the pressure is zero.
    • Slowly open the door to let out steam gradually. Keep your face away from the door.
    • Allow items to stand in the autoclave for 10 min. Cautiously remove items and place them in a safe area to cool. Do not agitate containers, as boiling or superheated liquids can explode if moved too quickly.
    • Make an entry in the logbook.
5.2 Biological Safety

5.2 Infrastructure, PPE & Systems

Table 5.2   Biosafety Level (BSL) Classification and Requirements
BSL-1
(Low Risk) 		BSL-2
(Moderate Risk) 		BSL-3
(High Risk, Aerosol Transmission)
Type of
microorganisms 		Not known to consistently cause disease in healthy adults (e.g., non-pathogenic E. coli, etc). Indigenous or exotic agents pose a moderate hazard; they can cause human disease but are usually treatable. (e.g., Staphylococcus aureus, Salmonella, Bacillus species, Clostridium species in their spore state, or fungal spores). Indigenous or exotic agents with potential for aerosol transmission can cause serious or potentially lethal disease (e.g., Mycobacterium tuberculosis, Yellow Fever, SARS-CoV, Influenza, etc).
Laboratory
Infrastructure 		1. Open benchtop worktable.
2. A sink for hand washing.
3. Lockable doors.
4. Non-porous, easily cleaned surfaces (floors, benches, chairs).
5. Incubators
6. Oven
7. Other equipment as per the BSL1 requirements
8. Pest control. 		All BSL-1 infrastructure, and additionally:

1. Self-closing doors.
2. Biosafety cabinets (Class I or II) for aerosol-generating procedures.
3. Access to an autoclave or other decontamination methods.
4. Eyewash station.
5. Vacuum lines with HEPA filters.
6. Other equipment as per the BSL2 requirements.
7. Mechanical ventilation with inward airflow is recommended. 		All BSL-2 infrastructure and additionally:

1. Physical separation from public access corridors.
2. Self-closing, double-door access (e.g., through an anteroom).
3. Biosafety cabinets Class II or Class III.
4. A dedicated ventilation system with non-recirculated, HEPA-filtered exhaust air.
5. Sustained negative airflow into the laboratory (air pressure gradient).
6. Walls, floors, and ceilings should be sealed and easily decontaminated.
7. The hand-washing sink near the exit has hands-free operation.
8. Autoclave within the lab or immediately adjacent.
Personnel
Protective
Equipment
(PPE) 		1. Please see the PPE guidelines
2. Lab coats, gloves.
3. Eye protection/ face shields when a splash hazard exists. 		1. Please see the PPE guidelines
2. Gloves.
3. Eye protection and face shields as needed.
4. Dedicated lab coats for cell culture work. 		1. Please see the PPE guidelines.
2. Protective lab clothing (solid-front wraparound gowns, scrub suits, coveralls).
3. Gloves (double).
4. Respiratory protection (e.g., N95 mask, & respirators).
Training &
Qualification 		Basic lab safety & hygiene 1. Comprehensive training on specific hazards, PPE, and BSC usage procedures (spills, exposures).

2. All personnel handling spore-forming agents must receive specific training on the unique risks and decontamination procedures for spores. 		1. Extensive, specialized training and expertise in BSL-3 practices.

2. Regular emergency response training (Spill, medical, containment breach).

3. Proficiency testing for aseptic technique, biosafety knowledge, and equipment operation.

4. A thorough medical status (immunocompromised, allergic reactions, latent disease, chest X-rays, vaccine status) is required.

Chemical Safety Fig 5.4 PPE for BSL-1, BSL-2 Laboratories Chemical Safety Fig 5.4 PPE for BSL-3 Laboratories
5.3 Biological Safety

5.3 Spill Control

  1. Ensure the Bio-safety kit is readily available and fully stocked at all BSLs.
  2. Remain Calm: Assess the situation without panic.
  3. Self-Protection: Don appropriate PPE before initiating cleanup as mentioned in the IISc safety manual
  4. Contain & Decontaminate: Prevent spread and neutralize the biological agent.
  5. Safe Disposal: Properly dispose of all contaminated materials.
  6. Report and Document: Ensure all incidents are recorded for improvement and compliance with the OLSEH Guideline.
5.3 Spill Control

5.3.1 Bio Spill Kit Contents

  1. BSL-1 & BSL-2: Freshly prepared 10% household bleach solution (1:10 dilution of 5.25% sodium hypochlorite), or other lab-approved broad-spectrum disinfectant.
  2. BSL-3: Highly effective broad-spectrum disinfectant validated for the specific agents handled (e.g. higher concentration of bleach, peracetic acid, or specialised virucidal/sporocidal agents). Ensure sufficient quantity.
  3. Absorbent materials: Paper towels, absorbent pads, spill pillows.
  4. Biohazard bags: Leak-proof, autoclavable (especially for BSL-2 and BSL-3).
  5. Sharps container: Puncture-resistant.
  6. Tools: Forceps/tongs, dustpan, and brush (for broken glass).
  7. Personal Protective Equipment (PPE):
    • BSL-1: Disposable gloves, lab coats, safety glasses.
    • BSL-2: Disposable gloves (consider double gloving), lab coat/disposable gown, safety glasses/goggles, face shield.
    • BSL-3: Full body coverage (e.g. disposable coveralls/Tyvek suit), double gloves, head cover/bonnet, shoe covers, full face shield, and respirator (N95 or higher, or powered air-purifying respirator (PAPR) depending on risk assessment and agent).
  8. Warning signs: “DO NOT ENTER” / “BIOHAZARD SPILL”
  9. Incident report forms.
5.3 Spill Control

5.3.2 BSL-1 Spill

Agents: Well-characterised agents not known to cause disease in healthy adults (e.g. E. coli K-12, Saccharomyces cerevisiae)

  1. Alert others in the immediate area to prevent further contamination.
  2. Don appropriate PPE – lab coat, disposable gloves, and safety glasses.
  3. Cover the spill with absorbent material (e.g. paper towels).
  4. Carefully pour disinfectant (e.g., 10% bleach solution) over the absorbent material, working from the edge inward to prevent spreading.
  5. Allow recommended contact time for the disinfectant (typically 15-20 minutes).
  6. Wipe up the spill from the edges to the centre using fresh absorbent material. If broken glass or sharps are present, use forceps or tongs to pick them up and place them directly into a sharps container. NEVER use your hands.
  7. Clean the spill area again with fresh absorbent material soaked in disinfectant.
  8. Dispose of all contaminated materials (used PPE, absorbent materials, etc.) into a biohazard bag.
  9. Remove PPE and dispose of it in the biohazard bag.
  10. Wash your hands thoroughly with soap and water.
  11. Report the incident to your PI and department safety champion.
  12. File an incident report and submit it to OLSEH.
5.3 Spill Control

5.3.3 BSL-2 Spill

Agents: Agents associated with human disease, but with low individual risk (e.g. Staphylococcus aureus, Salmonella, non-aerosolised Mycobacterium tuberculosis cultures, etc).

  1. Small spill (e.g. a few drops to a few milliliters, no aerosol generation outside BSC):
    • Ensure absorbent materials and biohazard bags are autoclavable if the waste requires autoclaving before disposal.
    • Follow steps 1-11 of BSL-1 Spill Procedure.
  2. Spill Inside a Biological Safety Cabinet (BSC):
    • Leave the BSC blower on. Do not turn off the BSC.
    • Don appropriate PPE – lab coat, gloves, and eye protection.
    • Cover the spill with absorbent material.
    • Carefully pour disinfectant over the absorbent material and the spill.
    • Allow appropriate contact time, wipe the spill with paper towels, and work from the edges to the centre. Use forceps for broken glass/sharps.
    • Wipe down all interior surfaces of the BSC (work surface, walls, drain pan/ catch basin if accessible) with disinfectant.
    • Autoclave all cleanup materials (paper towels, gloves, etc.) before discarding them into the biohazard waste stream.
    • Wash your hands thoroughly.
    • Report the incident to your PI and department safety champion.
    • File an incident report and submit it to OLSEH.
Chemical Safety Fig 5.5 Biological spill kit contents and cleanup steps
  1. Large Spill or Potential for Aerosol Generation (outside BSC):
    • DO NOT PANIC!
    • Immediately vacate the area. Alert others to evacuate the laboratory.
    • Close doors to the affected area to contain aerosols.
    • Post “DO NOT ENTER” / “BIOHAZARD SPILL” signs on all entrances.
    • Allow aerosols to settle for at least 30 minutes (this allows for air changes and settling of airborne particles).
    • Contact your PI, department safety champion, and OLSEH/Biosafety Officer immediately.
    • Provide details: Location, approximate volume, type of material, and any known hazards.
    • Don full appropriate PPE from the spill kit: lab coat/disposable gown, double gloves, safety glasses/face shield, shoe covers, and an N95 respirator if inhalation risk is present.
    • Enter the room cautiously, cover the spill with absorbent material, working from the edges inward.
    • Carefully pour disinfectant (e.g. 10% bleach solution) over the absorbent material and the entire spill area, starting from the perimeter and working towards the centre. Avoid splashing or creating new aerosols. Ensure complete saturation.
    • Allow adequate contact time (typically 20-30 minutes, or longer for high organic load like blood). Use forceps/tongs for sharps; dispose directly into a sharps container.
    • Re-disinfect the entire spill area and any potentially contaminated surfaces (benches, equipment, walls).
    • Dispose of all contaminated materials into autoclavable biohazard bags.
    • Remove PPE in a manner that avoids secondary contamination. Dispose of all disposable PPE in the biohazard bag.
    • Autoclave all biohazard waste as per institutional guidelines before final disposal. Wash your hands thoroughly with soap and water.
    • File an incident report and submit it to OLSEH.
5.3 Spill Control

5.3.4 BSL-3 Spill

Agents: Indigenous or exotic agents that may cause serious or potentially lethal disease through inhalation (e.g. Mycobacterium tuberculosis (aerosolised), Brucella spp., SARS-CoV-2, etc.).

  1. Evacuate:
    • DO NOT PANIC!
    • Immediately vacate the BSL-3 laboratory/suite.
    • Alert all personnel in the BSL-3 suite to evacuate immediately.
    • Activate emergency alarms and immediately notify the Security, PI/lab supervisor, and Biosafety officer/OLSEH.
    • Close all doors to the BSL-3 suite and ensure primary airlock doors are secured.
    • Post “DO NOT ENTER” / “BIOHAZARD SPILL - BSL-3 HAZARD” signs on all entrances.
  2. Cleanup by trained personnel:
    • PIs, the facility in-charge, and the Biosafety officer/OLSEH will coordinate the response.
    • Allow aerosols to settle for at least 30-60 minutes, or longer as determined by risk assessment and ventilation system capabilities (e.g. multiple air changes). The directional airflow system of BSL-3 should assist in containment.
    • Assess the situation remotely (if possible) and plan the cleanup strategy, considering the spill’s specific agent, volume, and location.
    • Restrict lab access to only authorised cleanup personnel.
    • Designate a cleanup team of at least two fully trained individuals.
  3. Spill Cleanup (by trained personnel only):
    • Don full, appropriate PPE for BSL-3 work, ensuring proper donning sequence and seal (e.g. disposable coveralls/Tyvek suit, double gloves, shoe covers, head cover, full face shield, and N-100 respirator with proper fit-testing or N95 Mask with a three-layered one normal mask). Consider a liquid-resistant outer layer when dealing with large liquid spills.
    • Ensure the bio spill kit is complete and readily available outside the contaminated area before entry.
    • Enter the BSL-3 lab/suite cautiously.
    • Carefully cover the entire spill area with absorbent material to minimise aerosol generation.
    • Slowly pour highly effective disinfectant (validated for the specific agent, often a higher concentration of bleach, or other virucidal/sporocidal agent) around the edges of the spill, working inward. Ensure complete saturation. Avoid splashing.
    • Allow extended contact time for the disinfectant (e.g. 30 minutes or more, depending on the agent and disinfectant specifications).
    • Carefully collect all contaminated materials (absorbents, disposable PPE, broken glass/sharps in sharps containers) using mechanical means (forceps, tongs, scoop). Place everything into autoclavable biohazard bags.
    • Thoroughly disinfect all potentially contaminated surfaces (work surfaces, equipment, walls, floor, handles, light switches, BSC exterior) with fresh disinfectant. This may require multiple wipes.
    • If the spill was in a BSC and containment was compromised, the BSC itself must be decontaminated, possibly through gas decontamination using formaldehyde, chlorine dioxide, and hydrogen peroxide, by trained personnel after the immediate spill cleanup.
    • Clean the spill area again with fresh disinfectant.
  4. Doffing & Decontamination:
    • Perform doffing of PPE in the designated BSL-3 exit area/anteroom following a strict, pre-determined sequence to prevent contamination of personal clothing.
    • Place all disposable PPE into autoclavable biohazard bags.
    • Autoclave all biohazard waste generated from the spill cleanup and contaminated PPE immediately, per institutional and BMW2018 guidelines. This is critical for BSL-3 waste.
    • Wash your hands thoroughly with antiseptic soap and water.
  5. Post-Spill & Reporting:
    • File an incident report and submit it to OLSEH.
    • Replenish the BSL-3 spill kit.
    • Consider environmental monitoring (e.g. surface swabs) to confirm complete decontamination, especially for high-risk agents.
5.3 Spill Control

5.3.5 Spill On Body/Clothing

  1. Immediately remove contaminated clothing while minimising contact with skin.
  2. Wash exposed skin thoroughly with antiseptic soap and water for at least 15-20 minutes.
  3. Immediately flush eyes at an eyewash station for at least 15 minutes for eye exposure.
  4. Seek immediate medical attention. This is critical for BSL-2 or BSL-3 agents, and post-exposure prophylaxis (PEP) may be necessary. Inform the IISc Health Centre of the specific agent
  5. . File an incident report and submit it to OLSEH.
  6. Contaminated clothing should be placed in an autoclavable bag for proper decontamination (e.g., autoclaving or specialised laundry).
5.3 Spill Control

5.3.6 Biowaste Disposal As Per BMW Rules, 2018

Category Type of Waste Colour and Type of Container Treatment and Disposal Options
Yellow
Yellow Biohazard Waste Bin
  1. Human Anatomical Waste (human tissues, organs, body parts)
  2. Animal Anatomical Waste
  3. Soiled waste (items contaminated with blood, body fluids like dressings, plaster casts, cotton swabs, bags containing residual/ discarded blood and blood components), expired or discarded medicines.
  4. Microbiology, Biotechnology & Clinical Lab Waste (lab cultures, microbial stocks, specimens, live/attenuated vaccines)
Yellow colour non-chlorinated plastic bags or containers (with biohazard symbol)
  1. Incineration, Plasma Pyrolysis, or Deep Burial (for specific cases like human anatomical waste).
  2. Discarded blood bags are counted, sealed, weighed, autoclaved on site, then sent in a yellow bag for incineration by CBMWTF.
Red
Red Biohazard Waste Bin
Contaminated waste (Recyclable) such as tubing, drains, oxygen masks, intravenous tubes, urine bags, gloves, and disposable items other than sharps Red colour non-chlorinated plastic bags and containers (with biohazard symbol) Autoclaving followed by Recycling. Needles of syringes must be cut/destroyed with a needle destroyer/cutter before putting them in red bags.
White
White Biohazard Sharps Container
Waste Sharps, including metals (needles, syringes with fixed needles, needles from needle tip cutter/burner, scalpels, blades, or any other contaminated sharp object that may cause puncture and cuts) White colour, puncture-proof, leak-proof, tamper-proof containers (with biohazard symbol) Autoclaving or Dry Heat Sterilisation in the lab, followed by Shredding or Chemical treatment in an authorised common biomedical waste treatment facility.
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Author: OLSEH Team
Last Updated on: 01 October 2026

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