first aiders can begin additional treatments or examination, as required if they possess the proper training (such as measuring pupil dilation). some organizations teach the same order of priority using the "3bs": breathing, bleeding, and bones (or "4bs": breathing, bleeding, burns, and bones). while the abcs and 3bs are taught to be performed sequentially, certain conditions may require the consideration of two steps simultaneously. this includes the provision of both artificial respiration and chest compressions to someone who is not breathing and has no pulse, and the consideration of cervical spine injuries when ensuring an open airway. skills applicable to the wider context are reflected in the mnemonic amega, which refers to the tasks of "assess", "make safe", "emergency aid", "get help" and "aftermath". the aftermath tasks include recording and reporting, continued care of patients and the welfare of responders and the replacement of used first aid kit elements. preserving life the patient must have an open airway—that is, an unobstructed passage that allows air to travel from the open mouth or uncongested nose, down through the pharynx and into the lungs. conscious people maintain their own airway automatically, but those who are unconscious (with a gcs of less than 8) may be unable to do so, as the part of the brain that manages spontaneous breathing may not be functioning. whether conscious or not, the patient may be placed in the recovery position, laying on their side. in addition to relaxing the patient, this can have the effect of clearing the tongue from the pharynx. it also avoids a common cause of death in unconscious patients, which is choking on regurgitated stomach contents. the airway can also become blocked by a foreign object. to dislodge the object and prevent choking, the first aider may use techniques such as 'back slaps' and 'abdominal thrusts'. once the airway has been opened, the first aider would reassess the patient's breathing. if there is no breathing, or the patient is not breathing normally (e.g. agonal breathing), the first aider would initiate cpr, which attempts to restart the patient's breathing by forcing air into the lungs. they may also manually massage the heart to promote blood flow around the body. if the choking person is an infant, the procedure is to deliver five strong blows on the infant's upper back after placing the infant's face in the aider's forearm. if the infant is able to cough or cry, no breathing assistance should be given. coughing and crying indicate the airway is open and the foreign object will likely to come out from the force the coughing or crying produces. a first responder should know how to use an automatic external defibrillator (aed) in the case of a person having a sudden cardiac arrest. the survival rate of those who have a cardiac arrest outside of the hospital is low. permanent brain damage sets in after 5 minutes of no oxygen delivery, so rapid action on the part of the rescuer is necessary. an aed is a device that can examine a heartbeat and produce electric shocks to restart the heart. a first aider should be prepared to quickly deal with less severe problems such as cuts, grazes or bone fracture. they may be able to completely resolve a situation if they have the proper training and equipment. for situations that are more severe, complex or dangerous, a first aider might need to do the best they can with the equipment they have, and wait for an ambulance to arrive at the scene. training principles first aid scenario training in progress basic principles, such as knowing the use of adhesive bandage or applying direct pressure on a bleed, are often acquired passively through life experiences. however, to provide effective, life-saving first aid interventions requires instruction and practical training. this is especially true where it relates to potentially fatal illnesses and injuries, such as those that require cpr; these procedures may be invasive, and carry a risk of further injury to the patient and the provider. as with any training, it is more useful if it occurs before an actual emergency, and in many countries, emergency ambulance dispatchers may give basic first aid instructions over the phone while the ambulance is on the way. training is generally provided by attending a course, typically leading to certification. due to regular changes in procedures and protocols, based on updated clinical knowledge, and to maintain skill, attendance at regular refresher courses or re-certification is often necessary. first aid training is often available through community organizations such as the red cross and st. john ambulance, or through commercial providers, who will train people for a fee. this commercial training is most common for training of employees to perform first aid in their workplace. many community organizations also provide a commercial service, which complements their community programmes. 1.junior level certificate basic life support 2.senior level certificate 3.special certificate types of first aid which require training a first aid box there are several types of first aid (and first aider) that require specific additional training. these are usually undertaken to fulfill the demands of the work or activity undertaken. aquatic/marine first aid is usually practiced by professionals such as lifeguards, professional mariners or in diver rescue, and covers the specific problems which may be faced after water-based rescue or delayed medevac. battlefield first aid takes into account the specific needs of treating wounded combatants and non-combatants during armed conflict. conflict first aid focuses on support for stability and recovery of personal, social, group or system well-being and to address circumstantial safety needs. shown here is an example of a way for people to practice cpr in a safe and reliable manner. hyperbaric first aid may be practiced by underwater diving professionals, who need to treat conditions such as decompression sickness. oxygen first aid is the providing of oxygen to casualties with conditions resulting in hypoxia. it is also a standard first aid procedure for underwater diving incidents where gas bubble formation in the tissues is possible. wilderness first aid is the provision of first aid under conditions where the arrival of emergency responders or the evacuation of an injured person may be delayed due to constraints of terrain, weather, and available persons or equipment. it may be necessary to care for an injured person for several hours or days. mental health first aid is taught independently of physical first aid. how to support someone experiencing a mental health problem or in a crisis situation. also how to identify the first signs of someone developing mental ill health and guide people towards appropriate help. first aid services first aider of the british red cross accompanies parade of morris dancers at the knutsford royal may day, knutsford, cheshire, england, 2012 some people undertake specific training in order to provide first aid at public or private events, during filming, or other places where people gather. they may be designated as a first aider, or use some other title. this role may be undertaken on a voluntary basis, with organisations such as the red cross society and st. john ambulance, or as paid employment with a medical contractor. people performing a first aid role, whether in a professional or voluntary capacity, are often expected to have a high level of first aid training and are often uniformed. symbols although commonly associated with first aid, the symbol of a red cross is an official protective symbol of the red cross. according to the geneva conventions and other international laws, the use of this and similar symbols is reserved for official agencies of the international red cross and red crescent, and as a protective emblem for medical personnel and facilities in combat situations. use by any other person or organization is illegal, and may lead to prosecution. the internationally accepted symbol for first aid is the white cross on a green background shown below. some organizations may make use of the star of life, although this is usually reserved for use by ambulance services, or may use symbols such as the maltese cross, like the order of malta ambulance corps and st john ambulance. other symbols may also be used. iso first aid symbol st. andrew's first aid badge emblem of the red cross emblem of the red crescent maltese or amalfi cross star of life civil defense physical conditions that often require first aid