How can you know if the substance you are about to pack is considered to be dangerous? The World Health Organization (WHO) has issued a Guidance on regulations for the Transport of Infectious Substances which includes several questions to find out whether any sample contains a dangerous substance or not, and its category:
These are the questions an expert must answer:
- Do you know whether or not it contains infectious substances?
- Have any pathogens been neutralized or inactivated, so that they no longer pose a health risk?
- May it contain microorganisms that are nonpathogenic to humans or animals?
- Is it in a state in which any pathogens that should appear have been neutralized or inactivated so that they no longer pose a health risk?
- Is it an environmental sample (including food and water samples) that is not considered to pose a significant risk of infection?
- Is it a dried blood spot?
- Is it a fecal occult blood screening test?
- Is it a medical or a clinical decontaminated waste?
- Is it for transfusion or transplantation?
If the answer is positive, then the substance is not subject to the transport requirements for dangerous goods. But if the answer is negative or unclear, then it should be considered as an infectious substance. To which category does it belong? In order to choose the correct category, you must find out if it meets the definition of a Category A substance. If it does not, then it is a Category B specimen, unless an informed professional judgment determines there is only a minimal likelihood that pathogens are present.
To sum up: if you cannot determine if the substance is especially dangerous (as materials contained in category A list) or pathogens-free, then it should be considered a Category B sample.