Practitioners of aromatherapy apply essential oils using several different methods, including (1) indirect inhalation via a room diffuser or drops of oil placed near the patient (e.g., on a tissue), (2) direct inhalation used in an individual inhaler (e.g., a few drops of essential oil floated on top of hot water to aid a sinus headache), or (3) aromatherapy massage, which is the application to the body of essential oils diluted in a carrier oil. Other direct and indirect applications include mixing essential oils in bath salts and lotions or applying them to dressings. Different aromatherapy practitioners may have different recipes for treating specific conditions, involving various combinations of oils and methods of application. Differences seem to be practitioner-dependent, with some common uses more accepted throughout the aromatherapy community. Training and certification in aromatherapy for lay practitioners is available at several schools throughout the United States and United Kingdom, but there is no professional standardization in the United States, and no license is required to practice in either country. Thus, there is little consistency in the specific treatments used for specific illnesses among practitioners. This lack of standardization has led to poor consistency in research on the effects of aromatherapy, because anecdotal evidence alone or previous experience has driven the choice of oils, and different researchers often choose different oils when studying the same applications. However, there are now specific courses for licensed health professionals that give nursing or continuing medical education contact hours, including a small research component and information on evaluating/measuring outcomes.
The National Association for Holistic Aromatherapy (NAHA) (www.naha.org/) and the Alliance of International Aromatherapists (www.alliance-aromatherapists.org) are the two governing bodies for national educational standards for aromatherapists. NAHA is taking steps toward standardizing aromatherapy certification in the United States. Many schools offer certificate programs approved by NAHA. A list of these schools can be found on the NAHA Web site (www.naha.org/schools_level_one_two.htm). National examinations in aromatherapy are held twice per year.
The Canadian Federation of Aromatherapists has established standards for aromatherapy certification in Canada (www.cfacanada.com/). They also have standards for safety and professional conduct and a public directory of certified aromatherapists. Other countries may have similar organizations.