According to the Health&Safety Advisor, you're a Good Samaritan if you help a person when you have no legal duty to do so. As a Good Samaritan you give your help without being paid and you give it in good faith.
This means, whenever you help a person in an emergency situation, you should abide by the following principles:
Are you designated first aider? Make sure you stick to these eight Good Samaritan principles
#1: Identify yourself as a first aider so the person feels comfortable that you know what you're doing.
#2: Get permission to help him before you touch him. Everyone has the right not to be touched by another person. As a first aider, you must respect this right. Ask if you can help.
If he answers 'yes,' you have consent to help him. If he doesn't answer you or doesn't object to your help, you have what's called implied consent.
#3: If he's unresponsive and relatives are present, ask for consent from the injured person's relatives. If no relatives are available, you have implied consent to carry on and give first aid.
#4: A person has the right to refuse help and not give you consent to go ahead and assist him. In this case, don't force first aid on a conscious injured person.
#5: Use your reasonable skill and care according to the level of training you have. When in question, care that's given will be measured against what a reasonable person with the same level of knowledge and skill would do.
#6: Give first aid with caution so you don't aggravate injury. Make sure you only do what you know you can and that all your actions help the injured person in some way.
#7: Don't be negligent in what you do. When you give first aid, make sure your actions are in the injured person's best interest. Give the care you'd like to receive if you were in the injured person's position.
#8: Don't abandon the injured person. Once he accepts your offer to assist him, don't leave him. Stay with him until:
Remember, as a designated first aider, you're a Good Samaritan. So make sure you abide by these principles when performing CPR.