Sources: 

http://www.delawareeyes.com 

http://care.diabetesjournals.org/content/diacare/33/5/998.full.pdf 

http://www.alertdiver.com/Fewer-Chambers-Available-for-Emergencies 

https://journals.plos.org/plosone/article?id=info%3Adoi/10.1371/journal.pone.0079995 

https://www.hopkinsmedicine.org/healthlibrary/conditions/physical_medicine_and_rehabilitation/hyperbaric_oxygen_therapy_134,147 

https://uihc.org/health-topics/hyperbaric-oxygen-therapy-resources-providers 

https://www.ncbi.nlm.nih.gov/books/NBK430855/