If there are any hazards or anything that poses a threat to a person or property, you may not be feeling so safe. A physical hazard is anything physical that may cause harm to the body. There is a specialized group of physical hazards which are the mechanical hazards, these are the machines and other movable devices that may cause harm to the body. Good nutrition is important to everyone's health, and nutrition is thus an important part of the health history assessment. Good personal hygiene is important that refers to the science, practice, maintenance, and preservation of health and well-being through cleanliness. To best meet the needs of a patient, nurses must learn the principles of therapeutic communication. Your immune system protects you from foreign invaders that might harm you. When your immune system responds to these threats, it's called an immune response.