Situational irony refers to a situation where the outcome and the expectations or intentions are not what is expected. In other words, the actions or intentions are not in line with the outcome. One illustrative example of situational irony would be if a fire station were to burn down.
If an individual were to examine the theatrical characters Romeo and Juliet, and their deaths, this would also provide an example of situational irony. Romeo finds Juliet after she had been drugged, and assumes her dead. He then kills himself. Juliet later awakens to find a deceased Romeo and kills herself.