Excerpts from community.nfpa.org:

NFPA has issued a firefighter protective hood safety bulletin as the fire service grapples with PPE contaminants and increases in job-related cancer.
Firefighters and their PPE are exposed to a wide range of toxins. According to a study by the CDC and NIOSH, firefighters have a higher chance of developing more than a dozen different cancers than the general population.

Firefighter thermal/flame protective hoods do not stop soot and chemicals from depositing on areas that are extremely vulnerable to dermal exposure. The hoods are designed to protect a firefighter’s head and neck, but they are not built to prevent toxins from being absorbed into a firefighter’s skin. The greatest number of carcinogens enter a firefighter’s body through the lungs; with the skin being the second most concerning access route. Furthermore, if the hoods are not properly cleaned, the toxins will linger in the hoods and rub against the firefighter’s skin.
NFPA is currently working on three research projects related to contamination, PPE and cancer. In the meantime, the protective hood bulletin recommends that fire departments educate personnel on PPE care and maintenance in accordance with NFPA 1851, the Standard on Selection, Care, and Maintenance of Protective Ensembles for Structural Fire Fighting and Proximity Fire Fighting.

ProtectiveHoodBulletin to keep firefighters safer from carcinogens and hazardous substances. For additional information, visit NFPA’s PPE cleaning page.