Decontamination is a process that makes a medical device, instrument or environmental surface safe to handle. It includes sterilization, disinfection and cleaning. All infectious materials and contaminated equipment should be decontaminated before being washed, stored or discarded. Autoclaving is the preferred method, and each individual working with biohazardous material is responsible for proper handling.
Lab equipment decontamination is more important than ever after the COVID-19 pandemic. Depending on the lab's biosafety levels, they require different decontamination procedures. The level of decontamination ranges from high-level sterilization to simple cleaning with mild detergent and water. While lab personnel can perform a few methods on a routine basis, most labs need professionals to properly decontaminate their equipment. It is important to follow manufacturer guidelines and protocols to ensure proper decontamination procedures are followed.
The first level of decontamination is cleaning. It is the most basic level and removes soil or organic material while reducing the number of microorganisms on an object. Disinfection is the second level and involves the use of chemicals or heat application. It reduces the number of microbes on an object or surface but does not totally eliminate them. The surface must be properly cleaned prior to disinfection. Sterilization is the third level and destroys all microbial life, including highly resistant bacterial endospores. The methods used include heat, gas, steam, plasma and radiation.
There are four main categories of physical and chemical means of decontamination: heat sterilization (wet or dry), liquid disinfection, vapors and gases. Autoclaving is the most dependable method of sterilization. Liquid disinfectants can be generally classified as halogens, acids, alkalis, heavy metal salts, quaternary ammonium compounds, phenolic compounds, aldehydes, ketones, alcohols and amines. Vapors and gases, when used in closed systems and under controlled conditions of temperature and humidity, provide excellent disinfection. Always use chemical disinfectants in accordance with labeled instructions and do not use them past the expiration date.
Typically, ultraviolet radiation is used to maintain good air hygiene in airlocks, ventilated cabinets, and laboratory rooms by reducing levels of airborne microorganisms. Moreover, it is also used to reduce surface contamination in biological safety cabinets (BSC) and some laboratory rooms.
The list of surfaces in a lab that require decontamination is quite long and depends on the lab environment and materials that are handled. However, it is essential for laboratories that handle biological materials to have every surface decontaminated regularly.
Here is a list of lab items that require decontamination:
1. Refrigerators/Freezers:
These appliances may become a breeding ground for bacteria or other hazardous agents. Therefore, it is crucial to make sure that the interiors are entirely empty and the appliance is defrosted before having it decontaminated by a professional.
2. Biosafety Cabinets and Centrifuges:
Biosafety cabinets and centrifuges should also be regularly decontaminated by a professional. A routine schedule should be developed for centrifuges since the materials inside may be hazardous.
3. Fume Hoods:
Fume hoods use laminar airflow to eliminate toxic vapors and chemicals from the workspace. Therefore, regular certification and decontamination is essential.
4. Other Lab Equipment Needing Decontamination:
Ovens, incubators, water baths, scales, chemical storage cabinets, dehydrating units, and other lab machinery all require professional decontamination.
Equipment for processing or storing chemicals should be handled with care. Safely remove, drain, or discharge chemicals from the equipment. Collect materials for reuse or proper hazardous waste disposal. If needed, utilize an inert gas or liquid to purge or rinse out any chemical residues. In certain instances, rinsate may also require disposal as hazardous waste. Decontaminate contaminated refrigerators, ovens, and other equipment with impermeable surfaces by scrubbing them with warm soapy water.
When dealing with equipment used for processing or storing biological materials, ensure proper steps are taken. Remove any biological materials from the equipment. Clean the equipment thoroughly with warm, soapy water and scrub as needed. Sanitize using a 1:10 bleach solution. Allow a 10-minute contact time before rinsing metal surfaces, as bleach can be corrosive.
For more information on medical laboratory devices decontamination, you can refer to the following links:
Centers for Disease Control and Prevention (CDC) guidelines on decontamination of medical devices: https://www.cdc.gov/infectioncontrol/guidelines/disinfection/index.html
World Health Organization (WHO) guidelines on decontamination and sterilization of medical devices: https://www.who.int/publications/i/item/9789241549851
Association for the Advancement of Medical Instrumentation (AAMI) standards on medical device reprocessing: https://aami.org/
Please note that specific codes related to medical laboratory devices decontamination may vary based on regulations and guidelines in different regions or countries. It is recommended to consult with relevant authorities or professional organizations for specific code requirements.