Final answer:
The ratio of compressions to ventilations in one-rescuer CPR on an adult without an advanced airway is 30:2.
Step-by-step explanation:
The ratio of compressions to ventilations for one-rescuer CPR on an adult without an advanced airway is 30:2. This means that for every 30 compressions, you should provide 2 ventilations.
The current CPR standards call for compression of the chest at least 5 cm deep and at a rate of 100 compressions per minute. The emphasis is on performing high-quality chest compressions, rather than providing artificial respiration.
It's important to remember that these guidelines apply specifically to one-rescuer CPR on an adult without an advanced airway.