When someone collapses and stops breathing, every second matters. You might freeze in that moment, unsure what to do or worried about making things worse. That uncertainty can cost a life. Basic life support gives you a clear, proven framework for those critical moments when someone’s survival depends entirely on your immediate action.
Basic life support (BLS) is a set of emergency procedures used to maintain circulation and breathing in someone experiencing cardiac arrest or respiratory failure. The core techniques include chest compressions, rescue breathing, and using an automated external defibrillator (AED). These fundamental skills help keep oxygen flowing to the brain and other vital organs until advanced medical help arrives. When performed correctly and quickly, BLS can dramatically increase survival rates.
This guide explains what basic life support is, when you need to use it, and walks you through each step of the DRSABCD action plan. You’ll learn how to perform CPR correctly, use an AED effectively, and understand the training and certification options available across Australia. By the end, you’ll know exactly what BLS involves and how to respond confidently when someone needs immediate help.
What basic life support involves
Basic life support centres on three essential techniques that work together to maintain blood flow and oxygen delivery when someone’s heart or breathing has stopped. You’ll use chest compressions to manually pump blood through the body, perform rescue breathing to get oxygen into the lungs, and apply an automated external defibrillator to restore a normal heart rhythm. These techniques form the foundation of emergency response and bridge the gap between collapse and the arrival of paramedics.
Core BLS techniques you’ll perform
Chest compressions create artificial circulation by physically pushing blood through the heart and out to vital organs. You place your hands in the centre of the chest and push down firmly at a rate of 100 to 120 compressions per minute, compressing the chest about one-third of its depth. The rhythm matters just as much as the depth because inconsistent timing reduces the effectiveness of each compression.
Rescue breathing delivers oxygen directly into the person’s lungs when they can’t breathe on their own. You tilt the head back to open the airway, pinch the nose closed, and give two breaths after every 30 compressions. Each breath should last about one second and make the chest visibly rise. If you’re uncomfortable with mouth-to-mouth contact or don’t have a barrier device, compressions-only CPR still provides significant benefit.
Hands-only CPR can double or triple survival rates compared to doing nothing, even without rescue breaths.
Automated external defibrillators analyse the heart’s electrical activity and deliver controlled shocks to reset dangerous rhythms. You turn on the device, attach the pads to the bare chest, and follow the voice prompts. The AED tells you when to stand clear and when to resume compressions. Modern AEDs guide you through each step, making them safe for anyone to use.
When you need to apply BLS
You apply basic life support whenever someone becomes unresponsive and stops breathing normally. This includes cardiac arrest situations where the heart suddenly stops beating effectively. Look for absent or abnormal breathing (gasping, irregular breaths) combined with a complete lack of response to verbal commands or physical stimulation. You also use BLS techniques for drowning, choking, severe allergic reactions, or drug overdoses that compromise breathing or circulation.
Step 1. Recognise an emergency and call for help
Before you can apply what is basic life support, you need to identify when someone requires immediate intervention. The first step involves quickly assessing the situation and activating emergency services. You must recognise specific warning signs that indicate cardiac arrest or severe respiratory distress, then immediately call triple zero (000) to get paramedics on the way. Acting within the first few minutes determines whether someone survives.
Signs someone needs immediate help
Look for a person who is completely unresponsive when you call their name or gently shake their shoulders. They won’t open their eyes, speak, or move in response to your voice or touch. Check their breathing by watching their chest for movement and listening for breath sounds. Absent breathing or only occasional gasps (called agonal breathing) means you need to start BLS immediately.
Other critical signs include blue or grey skin colour (especially around the lips and fingernails), which indicates severe oxygen deprivation. You might notice the person’s chest moving irregularly or not at all. Some cardiac arrest victims make brief, infrequent gasping sounds that aren’t true breathing. These signs together confirm you’re facing a life-threatening emergency that requires immediate action.
How to call triple zero effectively
Dial 000 immediately before you start any resuscitation attempts if you’re alone with the victim. Tell the operator you need an ambulance and state clearly that someone is unresponsive and not breathing normally. The operator needs your exact location with landmarks to dispatch help quickly. Stay on the line because the call-taker can guide you through CPR steps if needed.
Emergency operators can provide real-time CPR instructions over the phone, increasing your confidence and effectiveness.
If other people are nearby, point to a specific person and tell them directly to call 000 while you begin chest compressions. Saying “someone call an ambulance” often results in everyone assuming someone else will do it. Direct one person to call emergency services and another to locate the nearest AED. This clear delegation ensures help arrives as quickly as possible while you maintain continuous chest compressions.
Step 2. Follow the DRSABCD action plan
Once you’ve confirmed someone needs help and called triple zero, you implement the DRSABCD action plan used across Australia. This systematic approach ensures you check each critical element in the correct order, from assessing dangers through to using a defibrillator. The acronym stands for Danger, Response, Send for help, Airway, Breathing, CPR, and Defibrillator. You’ve already handled “Send for help” in step one, so now you focus on the remaining elements that prepare you to deliver effective resuscitation.
Check for danger first
Survey the entire scene before you approach the person who needs help. Look for hazards like traffic, fire, smoke, electrical hazards, unstable structures, or aggressive bystanders. You can’t help anyone if you become a victim yourself. Move the person only if absolutely necessary to protect them or yourself from immediate danger, such as pulling someone from a burning car or away from traffic.
If you must move them, use proper manual handling techniques and drag them by their clothing at the shoulders, keeping their head and neck as stable as possible. Most situations allow you to provide care where you find them. Once you’ve confirmed the scene is safe, position yourself beside the person at shoulder level so you can easily access their head and chest.
Assess their response level
Speak loudly and clearly to get the person’s attention, asking “Can you hear me?” or “Are you okay?”. If they don’t respond to your voice, gently squeeze their shoulders and watch for any reaction. A responsive person might open their eyes, speak, groan, or move their limbs. Someone who shows no response or only minimal groaning without opening their eyes requires immediate basic life support.
An unconscious person who doesn’t respond to talk and touch needs CPR, even if you’re not sure about their condition.
Check for signs of life by looking for normal breathing and movement. Don’t waste time checking for a pulse because research shows even trained healthcare workers often make mistakes when checking pulses in emergencies. Your assessment of responsiveness and breathing tells you everything you need to know about whether to start resuscitation.
Open the airway and check breathing
Tilt the person’s head back by placing one hand on their forehead and lifting their chin up with your other hand. This head tilt-chin lift manoeuvre pulls the tongue away from the back of the throat, opening the airway. You’ll see the neck extend and the chin point upward. Look at their chest for movement, listen for breath sounds near their mouth and nose, and feel for air movement against your cheek. Take no more than 10 seconds for this assessment.
Normal breathing shows regular chest rise and fall with audible breath sounds. Absent breathing or only occasional gasps (which look like sudden, irregular movements) means you need to start CPR immediately. If you find food, vomit, or other objects blocking the airway, turn their head to the side and use your fingers to sweep the mouth clear. For someone who is breathing normally but unconscious, place them in the recovery position (on their side) and continue monitoring until help arrives.
Begin chest compressions without delay
Place the heel of one hand in the centre of their chest between the nipples on the lower half of the breastbone. Put your other hand on top and interlock your fingers, keeping your arms straight. Push down hard and fast at a rate of 100 to 120 compressions per minute, pressing to about one-third the depth of the chest (at least 5 cm for adults). Allow the chest to recoil completely between compressions, but keep your hands in position.
Continue compressions without stopping until an AED arrives, the person starts breathing normally, or paramedics take over. If you must give rescue breaths, deliver two breaths after every 30 compressions. The next step covers what is basic life support in terms of proper CPR technique and how to use the defibrillator when it arrives.
Step 3. Use CPR and an AED effectively
Understanding what is basic life support means knowing how to deliver high-quality CPR and use an automated external defibrillator properly. You combine continuous chest compressions with rescue breaths (if trained and willing) to maintain blood flow and oxygen delivery. The moment someone brings an AED to the scene, you attach it and follow its prompts while minimising interruptions to compressions. Quality matters as much as speed because poor technique reduces the person’s chance of survival.
Perform high-quality chest compressions
Position your hands correctly by placing the heel of one hand on the centre of the chest, directly on the lower half of the breastbone between the nipples. Stack your second hand on top and interlock your fingers, keeping them lifted off the chest. Lock your elbows straight and position your shoulders directly above your hands so you can use your body weight rather than arm strength. This alignment lets you deliver powerful compressions without tiring quickly.
Push hard and push fast at a rate of 100 to 120 compressions per minute, maintaining this rhythm without speeding up or slowing down. Compress the chest to at least 5 centimetres depth (about one-third of the chest depth) for adults. Allow the chest to recoil completely after each compression by lifting your weight without removing your hands from position. Complete recoil lets blood flow back into the heart between compressions.
Every 10-second pause in chest compressions significantly reduces the person’s survival chances, so minimise interruptions.
Count your compressions aloud (“one, two, three”) to maintain the correct rhythm and coordinate with anyone helping you. If you’re performing compressions-only CPR, continue without stopping until help arrives or the person starts breathing. Swap with another trained person every two minutes (roughly 200 compressions) to maintain quality, as even fit people tire quickly and deliver less effective compressions when fatigued.
Give effective rescue breaths
Tilt the head back and lift the chin to keep the airway open when you pause for rescue breaths. Pinch the person’s nose shut with your thumb and forefinger, take a normal breath, and seal your lips completely around their mouth. Blow steadily for one second while watching the chest rise, indicating air is entering the lungs. Remove your mouth and watch the chest fall, then give a second breath the same way.
Deliver two rescue breaths after every 30 compressions, keeping the pause as brief as possible. Each breath should make the chest visibly rise, but avoid blowing too hard or too fast because this forces air into the stomach rather than the lungs. If the chest doesn’t rise, reposition the head and try again with your next set of breaths. The 30:2 ratio (compressions to breaths) applies to all adult resuscitation situations.
Apply the AED correctly
Turn on the AED immediately when someone brings it to you. The device provides voice instructions that guide you through each step, starting with pad placement. Expose the person’s bare chest by removing or cutting away clothing, jewellery, and any medication patches. Quickly wipe away sweat or water with a towel because moisture reduces pad contact.
Attach the pads exactly as shown in the diagrams on each pad. Place one pad on the upper right chest below the collarbone and the other on the lower left chest below the armpit, both on bare skin. Press firmly around all edges to ensure complete contact. Most AEDs automatically begin analysing the heart rhythm once you plug in the connector cable.
Follow these steps when the AED analyses and delivers shocks:
- Stop compressions and ensure nobody touches the person during analysis
- Press the shock button if the AED tells you a shock is needed
- Resume compressions immediately after the shock without checking for signs of life
- Continue CPR for two minutes until the AED prompts you to pause for another analysis
- Repeat the cycle of analysis, shock (if needed), and CPR until paramedics arrive
The AED tells you when to stand clear and when to resume compressions. Never remove the pads once attached because the device continues monitoring the heart rhythm throughout your resuscitation efforts.
Training and certification for BLS in Australia
You access basic life support training through nationally accredited courses delivered by registered training organisations across Australia. Healthcare professionals need formal BLS certification to meet credentialing requirements, while members of the public can learn BLS skills through community first aid courses. Training takes between four hours and two days depending on the course level and whether you choose blended learning (online theory plus practical sessions) or full face-to-face delivery.
Accredited BLS courses you can take
HLTAID010 Provide basic emergency life support represents the national standard for BLS training in Australia. This course teaches you the DRSABCD action plan, CPR techniques, and AED use through hands-on practice with mannequins and defibrillator trainers. You complete practical assessments that demonstrate your competence in performing chest compressions, rescue breaths, and responding to various emergency scenarios.
Healthcare professionals typically require advanced life support courses like ALS 1 and ALS 2, which build on basic skills with additional techniques for managing airways, administering medications, and interpreting cardiac rhythms. Resuscitation Australia and the Australian Resuscitation Council accredit these courses, ensuring they align with current ANZCOR guidelines. Paediatric Advanced Life Support (PALS) courses provide specialised training for managing children and infants in cardiac arrest situations.
What your training includes
Your BLS course combines theory sessions covering recognition of cardiac arrest with extensive practical training on mannequins. Instructors teach you proper hand placement, compression depth and rate, rescue breathing technique, and AED operation through repeated practice. You work through realistic scenarios that simulate finding someone collapsed, calling for help, performing CPR, and using an AED until paramedics arrive.
Training with realistic scenarios builds the muscle memory and confidence you need to act quickly when facing an actual emergency.
Most courses include training on managing choking, positioning unconscious breathing casualties, and recognising when someone needs urgent medical help. You receive immediate feedback on your compression quality, timing, and overall technique during practical assessments. This hands-on approach ensures you understand what is basic life support not just in theory but through actual physical practice.
Certification requirements for healthcare professionals
Healthcare workers must renew their BLS certification annually to maintain current skills and knowledge. Your certificate remains valid for 12 months from the assessment date, after which you complete either a full recertification course or a shorter refresher depending on your organisation’s requirements. Hospitals, clinics, and other medical facilities typically mandate specific accreditation levels matched to your role and patient care responsibilities.
You earn Continuing Professional Development (CPD) points through BLS training, which count toward registration requirements with AHPRA and other professional bodies. Keep your certification current by scheduling renewal training at least one month before expiry to avoid gaps in your credentials.
Final thoughts
Understanding what is basic life support gives you the confidence to act decisively when someone’s life depends on your immediate response. You now know the DRSABCD action plan, proper CPR technique, and how to use an AED effectively. These skills form the foundation of emergency care that bridges the critical gap between cardiac arrest and advanced medical help.
Your knowledge remains theoretical until you practice these techniques hands-on with qualified instructors. Healthcare professionals need current certification to meet credentialing requirements and maintain professional standards. Regular training ensures your skills stay sharp and your muscle memory responds automatically when facing real emergencies.
Take the next step by enrolling in an accredited BLS or Advanced Life Support course that matches your professional requirements. Book your ALS training with Parasol Medical Training to gain nationally recognized certification from experienced instructors across major Australian cities.
