While entering the security guard field, you need to expect the unexpected. You will be dealing with a lot of people at once sometimes, and if something gets out of control, you need to be mentally and physically prepared. Since you cannot foresee an incident, you can keep training and learning self-defense tactics in order to be ready.
Before you even apply for a job in the field, you should start taking self-defense classes. It is the first stop in defense, and it is only natural that you should know how to protect yourself before attempting to protect others.
Many companies offer training, and you will either be trained with them, or they will most likely refer you to a course than you can get your training, if they are not able to provide it for you. Safety should always be on your mind and your employers as well.
Martial arts are also a great way to protect yourself, but you should talk about the type of defense courses availability for security guards with your instructor. It is an important matter, because many people, who do martial arts, do it for self-protection, while you also want to keep people around you safe.
Self-defense tactics, martial arts and any kind of training you can get from your employers, is just a few ways that you can protect yourself against harmful individuals. As a security guard, you can take action, but you should also be very careful, as you might encounter someone with weapon such as a gun or a knife.