laboratoryQuestion: Hello LCS Laboratory, we need to develop air sampling strategy for an old laboratory complex (1950s). The building is prone to power outages and at times the emergency generator does not engage. When this happens occupants experience an odor (volatiles) in multiple locations but most prevalent in the basement level. The chemical inventory is in the 1000s, so I don’t think its practical to sample for everything. Can you suggest what to sample for?

Answer: As a chemist I am very familiar with the smell that you described. It accumulates in storage cabinets and constantly trickles into the lab. Usually the storage cabinets are either part of a fume hood or connected to the exhaust system. In good lab they are always under small negative pressure…. as long as the power is on.

If your client cannot provide the list of what they work with, we can try to estimate what is there. We can roughly split all volatile chemicals on: acids, bases, oxidizers and solvents/organic.

Perchloric_acid_60_percentInorganic Acids. The most common volatile acids are HCl, and Nitric. They can be used as indicators of presence of acids in air. Watch for stains of wood and metal corrosion, you can use this as indicators of good housekeeping. If there are no acid spills, and jars are closed, it should be no corrosion.

Bases. Ammonia would be the only volatile product stored with other alkaline solutions.

Oxidizers. They are mostly nonvolatile with few exceptions like Hydrogen Peroxide, Bleach. Bleach produces Chlorine and Chlorine Oxide.

Those are the major contributor to the smell in laboratory. What is in the cabinet heavily depends on what they are working with. But in every laboratory you find solvents like acetone, acetonitrile, IPA, dichloromethane, hexane and so on. We can offer to test for those or any other solvents of your choice + total of other TVOC detected on the sample without their identification.

UFFI vapourVolatile Carcinogens: Benzene and Formaldehyde. If they use benzene, it can be tested with other solvents. Formaldehyde is always present in lab buildings. Some labs use it as a chemical, and it can be a product of off-gassing of laboratory furniture.

Just an idea for your consideration. If you can use handheld PID in your study, you can take the grab samples of air inside of the storage cabinets and outside of it. This will give you indication of good housekeeping (if the jars are closed it should be no smell in a cabinet), and show what is the source of odour in each room.

Let me know if you want to focus on one or other chemicals, and we will try to tailor proper testing technique for it. LCS Laboratory can offer air sampling pumps, free sampling media and laboratory testing for your survey.

Please email us to discuss your project.

Thank you again, Sincerely