A certified nursing assistant’s scope of practice covers basic patient care and activities of daily living, performed under the supervision of a licensed nurse. CNAs help patients eat, bathe, dress, and move around, while also measuring vital signs and reporting health changes. The exact boundaries vary by state and facility, but the core framework is consistent nationwide: CNAs provide hands-on personal care while leaving clinical judgment, assessments, and most medical procedures to licensed nurses.
Daily Tasks CNAs Are Authorized to Perform
The bulk of a CNA’s work centers on helping patients with things they can no longer do independently. This includes cleaning and bathing patients, helping them use the toilet and get dressed, turning or repositioning them in bed, and transferring them between beds and wheelchairs. CNAs also serve meals and assist patients who need help eating.
Beyond personal care, CNAs collect and document basic health data. They measure temperature, pulse, respiratory rate, blood pressure, and oxygen saturation using a pulse oximeter. Many facilities also consider a pain rating a routine part of vital sign collection. CNAs record height, weight, and fluid intake and output as well. They listen to patients’ health concerns and pass that information along to the nursing staff, acting as an essential link between patients and the clinical team.
Knowing When to Report Abnormal Findings
CNAs don’t interpret vital signs or make clinical decisions based on them, but they do need to recognize when something falls outside normal range and report it immediately. The general reporting thresholds give a sense of what CNAs are trained to watch for:
- Temperature: above 100.4°F (38°C), which indicates a fever
- Pulse: below 60 or above 100 beats per minute in an adult, or any irregular rhythm
- Respiratory rate: below 12 or above 20 breaths per minute
- Blood pressure: systolic below 90 or 130 and above, diastolic below 60 or 90 and above
- Oxygen saturation: below 94% for most adults (or below 88% for patients with chronic lung conditions)
- Weight changes: 3 pounds in 24 hours or 5 pounds within a week
The CNA’s job is to catch and communicate these changes, not to decide what to do about them. Any significant change in breathing, circulation, cognition, pain level, or a fall gets reported to the nurse right away.
Tasks That Fall Outside the Scope
The clearest boundary in a CNA’s scope of practice is clinical judgment. CNAs cannot perform nursing assessments, even when they observe something concerning. For example, a CNA might notice a red area on a patient’s skin and should absolutely report it, but formally assessing that skin breakdown is the nurse’s responsibility.
Other tasks that are off-limits unless a CNA has received additional specialized training and the facility’s written policy allows it:
- Administering medications or injections
- Inserting urinary catheters
- Administering tube feedings
- Performing wound care or dressing changes
CNAs also cannot delegate tasks to others or provide patient education. They can reinforce instructions a nurse has already given (like reminding a patient to keep their oxygen tubing in place while eating), but the initial teaching has to come from a licensed nurse.
How Supervision and Delegation Work
Every task a CNA performs is delegated by a licensed nurse, either an RN or an LPN working under an RN’s direction. The nurse who delegates a task remains accountable for the patient’s overall care, while the CNA is responsible for completing the specific task correctly. Before delegating, the nurse is expected to verify that the CNA has been trained and deemed competent for that particular skill.
This means a CNA’s day-to-day responsibilities can shift depending on what gets delegated. A nurse won’t assign a task the CNA hasn’t been trained for, and the instructions should be clear and specific. If something feels outside your training or comfort level, you’re expected to speak up rather than attempt it.
Scope Varies by State and Facility
Each state defines its own CNA scope of practice through its Nurse Practice Act and related regulations. On top of that, individual facilities create job descriptions that spell out what CNAs are expected to do within that specific workplace. The result is that two CNAs in different states, or even different facilities in the same state, may have noticeably different day-to-day responsibilities.
The most common example is medication administration. In some states and facilities, CNAs with additional training can dispense medications. This isn’t part of the traditional CNA role, but states that allow it require extra training and competency testing before a CNA can take it on. The largest employers of CNAs are skilled nursing facilities (37% of CNA jobs) and hospitals (30%), and the expectations in each setting differ. Hospital CNAs typically work alongside larger nursing teams with more specialized roles, while CNAs in skilled nursing facilities often develop closer, longer-term relationships with residents and may take on a broader range of daily care tasks.
The Medication Aide Pathway
Some states offer a formal medication aide certification that significantly expands what a CNA can do. In Ohio, for instance, a certified medication aide can administer prescription medications in nursing homes and residential care facilities under nurse supervision. This includes giving oral medications, applying topical treatments, administering eye, ear, and nose drops, and rectal or vaginal insertions. Medication aides can even give initial doses of new prescriptions and administer as-needed medications when the supervising nurse isn’t physically present. In some cases, they can inject insulin using a pre-dosed pen device, provided they’ve completed employer-specific training. All of this still requires delegation from a licensed nurse.
Training Requirements and Certification
The federal minimum for CNA training is 75 total hours, with at least 16 of those in clinical (hands-on) settings. In practice, state requirements range from 75 to 180 hours, with an average around 100 hours. About one-third of states set their requirements at the federal minimum. Research published in the Journal of Nursing Regulation found that states requiring more than 75 training hours had better patient outcomes, with lower rates of residents experiencing falls with injuries, pain, and difficulty with daily activities.
After completing a training program, CNAs must pass a competency exam and be placed on their state’s nurse aide registry. To work in a skilled nursing facility, active registry status is required. Renewal cycles vary by state. In Florida, for example, CNAs renew every two years and must complete at least 24 hours of in-service training during that period, plus demonstrate they’ve worked in a nursing-related role for pay within the preceding 24 months.
Privacy and Ethical Obligations
CNAs handle sensitive health information every shift, which places them squarely under federal privacy rules. Patient health information, whether spoken, written, or electronic, cannot be used or shared without the patient’s written permission unless the law specifically allows it. In practical terms, this means not discussing a patient’s condition in hallways, not sharing details with unauthorized family members, and limiting access to records to only what’s needed to do your job. The legal standard is “minimum necessary,” meaning you only look at or share the smallest amount of information required for the task at hand.