Answer:
The one-way valve should be checked to confirmed if is well fitted.
Step-by-step explanation:
The CPR mask is a safety device to aerate the victim blood, during oxygen shortage, it presented a physical barrier to prevent the mixing of the BLS saliva, and body-fluid with the patient own,
The fitted one-way valve , is for giving the victim breath for resuscitation with the valve to prevent likely vomits, mucus, fluids or blood( from involuntary regurgitation )due to compression of the chest during CPR from the mouth of the victim. Therefore this should be well checked to prevent possible suffocation.