Bad smell in the air? What to know and what to do.

There are plenty of unpleasant odors in the cabin. Most are harmless, but some are toxic, so it is important to be informed. Two types of fumes (unpleasant, odorous, and potentially toxic compounds) that can contaminate the air supply are engine oil and hydraulic fluid. It’s important to pay attention to the presence of unusual, unpleasant odors, especially if they are coming from the air supply vents, because those odors may be oil or hydraulic fumes, which are toxic and can make you sick. You need to report the fumes and minimize your exposure. This is true even if there‘s no visible smoke or haze. On some aircraft, because of the design, the air coming out of the cabin vents can be contaminated, while the flight deck airis just fine (or vice-versa). So, it’s important to let the pilots know about any irregular conditions in the cabin. This is what you need to know:

  1. If oil or hydraulic fumes contaminate the cabin air supply, then you will notice an unpleasant smell coming from the air supply vents. Typically, there is no haze or smoke – “just” a smell. Know that other types of fumes can come from the vents, too, like exhaust, fuel, and deicing fluid.
  • Oil fumes don’t usually smell like oil. Many people think they smell like dirty socks. Others say “chemicals,” “old cheese,” “wet dog,” “heated garbage,” etc. One aircraft manufacturer says that engine oil fumes can smell electrical. Hydraulic fumes have a distinctive acrid smell. The odors associated with exhaust, fuel, and deicing fluid fumes tend to be easier to recognize.
  • If you smell what could be oil or hydraulic fumes and are already onboard, quickly try to determine the source of the odor (fumes). Are they coming from an onboard item? Or are they coming from the air supply vents? Verify that nobody is cooking anything smelly, that the coffee pots are not burning, that the cabin lights are working and not burned out, and that the galley chiller lights are not indicating malfunction (red). (Not all of these possible sources will apply to all aircraft types.) Oil/hydraulic fumes come from the air supply vents, not from an in-cabin source. Sometimes, the source isn’t totally obvious.
  • Report the fumes to the pilots. Describe the WHAT (smell, intensity), WHERE (coming from air supply vents or something in the cabin, and forward, mid, aft, or combination), WHEN (phase of flight when noticeable), and WHY (whether anyone is sick/needs first aid, including oxygen).
  • If you are sick while the aircraft is at the gate, deplane and get medical attention. If you are sick inflight, use oxygen for first aid purposes (per your airline procedures), ask the pilots to call Medlink (if available at your carrier), and get medical attention after landing.
  • Post-flight debriefing? You have the right to an AFA union representative present.
  • More questions? Contact your AFA-CWA MEC Safety, Health, and Security Chair, Lori Kordosky: or XXX  Backup option is Judith Anderson, AFA-CWA Air Safety, Health, & Security Dept.: or 206-932-6237.