Many security jobs will require you to be CPR certified or trained in First Aid. Depending on the type of security role you are taking on, you could be the first to respond in emergencies and when dealing with the public. Talk to the interviewer about any certifications that you have or are currently acquiring. Bring certificates for your candidate file, in case the employer needs a copy. If you do not have any emergency response training, that is okay too! Just be sure to express an interest and willingness to gain these credentials.