What happens if you were exposed to harmful gases?

Question: What happens if you were exposed to harmful gases?
- Keywords:
  exposure,
  gas
Asked by Sammas to Matt on 20 Jun 2016.
- Matthew Hobbs answered on 20 Jun 2016:
  
  Thankfully this hasn’t happen to me and any engineer working with harmful gases would have protective equipment and training to deal with this

Question: What happens if you were exposed to harmful gases?