Grænseværdien for erhvervsmæssig eksponering er sat til 0,5 ppm (0,9&nbsp;mg/m<sup>3</sup>) i gennemsnit over en otte-timers-periode.<ref name=pocket>{{cite web
| last = [[Centers for Disease Control and Prevention]]
| first = 
| author-link = 
| title = Ketene
| work = NIOSH Pocket Guide to Chemical Hazards
| publisher = 
| date = 4. april 2013
| url = http://www.cdc.gov/niosh/npg/npgd0367.html
| doi = 
| access-date = 29. januar 2017
| archive-date = 20. december 2016
| archive-url = https://web.archive.org/web/20161220085236/https://www.cdc.gov/niosh/npg/npgd0367.html
|url-status=live
}} {{en sprog}}</ref>
[[IDLH]]-grænseværdien er sat til 5 ppm, da dette er den laveste koncentration, der kan fremkalde et klinisk relevant [[fysiologi]]sk respons hos mennesker.<ref name=idlh>{{cite web
| last = [[Centers for Disease Control and Prevention]]
| first = 
| author-link = 
| title = Ketene
| work = Documentation for Immediately Dangerous To Life or Health Concentrations (IDLHs)
| publisher = 
| date = maj 1994
| url = http://www.cdc.gov/niosh/idlh/463514.html
| doi = 
| access-date = 29. januar 2017
| archive-date = 20. december 2016
| archive-url = https://web.archive.org/web/20161220091846/https://www.cdc.gov/niosh/idlh/463514.html
|url-status=live
}} {{en sprog}}</ref>
Kemi