There have been a number of recent social media postings questioning the value of the ARC exam and of ARC itself.

The following information helps clarify some of the questions and concerns posed.

Firstly, ARC thanks everyone who took the time to post their concerns through social media and email. ARC loves tweeting @AromaCouncil and Facebooking at, but the best way to get questions or concerns answered by the volunteer ARC Board is by using one of the following emails: feedback@ or

Secondly, the goal of ARC has been constant since the nonprofit was established: to provide an unbiased, voluntary, standardized, independent test which is maintained and operated by the Professional Testing Company (PTC) to test aromatherapy concepts and knowledge with a focus on safety standards required for the professional practice of aromatherapy, in order to ensure public safety.

All ARC Board members are unpaid and volunteer their time to ensure that ARC’s goal is attained.

Further, every Registered Aromatherapist or person involved in practicing or teaching aromatherapy is invited to participate in this labor of self-regulation.

If you want to get involved in ARC, please let us know (via email at We will gladly add you to our growing list of aromatherapists committed to formal self-regulation through a voluntary exam and register, promoting the interests of the entire professional aromatherapy community.


The ARC Examination

The ARC exam is composed of multiple-choice questions submitted by educators, Registered Aromatherapists, and industry members. To ensure fair, valid, and reliable examinations that reflect current best practice of the aromatherapy profession, ARC, in accordance with PTC, follows rigorous processes in all stages of item and examination development consistent with guidelines recommended by assessment industry standards.

All items that appear on an exam go through multiple rounds of review by several subject matter experts, as well as test development specialists at PTC. Also, all items that appear on an exam target the knowledge areas specified in the content outline, which you can review in the Candidate Handbook (available for download at: and are written by subject matter experts specializing in aromatherapy.

Again, exam items reflect current best practices, and item writers are asked to provide at least two professional references for all multiple-choice questions. Once submitted, all new items (questions) go through editing and psychometric review by PTC.

Items then undergo a panel review and revision process by subject matter experts who are representative of the industry. This revision is done with guidance from a testing specialist from PTC.

The items are reviewed for adherence to pre-established criteria, such as: appropriateness for candidate population; consistency with ARC style and terminology; avoidance of bias and stereotyping; accuracy; and importance to the practice of aromatherapy.

Items deemed inappropriate for the exam or that cannot be revised to meet the above criteria are immediately eliminated. Items that do meet the criteria and are accepted by the review panel are then entered into the item bank and carefully proofread by PTC staff trained in item structure to ensure grammar and stylistic changes are consistent.

The items undergo additional review and scrutiny by PTC and ARC when each exam is developed. After the exam administration, item performance statistics are carefully reviewed and used as a guideline for further item enhancement and revision.

For full instructions on how to submit questions, please review the ARC FAQ section “Where did the questions come from” at: Please do not send new items (questions) directly to any ARC Board member, which automatically invalidates them.

All Registered Aromatherapists are invited to participate in item reviews. The review team is sequestered during the review and the reviewers are not permitted to keep or retain copies of the questions.



ARC Board members are not permitted to see or sit the exam.

PTC administers a large number of registration exams. You can review the list at:


PTC sends new editions of the ARC newsletter to all Registered Aromatherapists via email. Since volunteers write the newsletter, publication is intermittent. Everyone is welcome to submit newsletter articles or to run a paid advertisement. Previous editions can be download from the ARC website. For writing and advertising guidelines, visit:


Professional Relationships with Membership Organizations

ARC provides support for the National Association for Holistic Aromatherapy (NAHA) and Alliance of International Aromatherapists (AIA), and both membership organizations are listed here under News & Links:

  • To be eligible to sit the exam, a candidate must complete a minimum of a 200 hour program that is in compliance with both NAHA and AIA; and
  • The candidate has to have current membership in either NAHA or AIA.

ARC provides information about NAHA and AIA on the Industry page of the ARC website (including links).

Also, the Candidate Handbook provides a list of recommended reference texts. If you have a reference text you would like to see added to the following list, please forward it (email:

The Candidate Handbook says:

The following list of references may be of some help in preparing for the examination.  This list does not attempt to include all acceptable references nor is it suggested that the ARC™ Registration Examination in Aromatherapy is necessarily based on these references.  Their content, while representative of the type of knowledge and skills tested on the Registration Examination, does not necessarily mirror the content of the Registration Examination. ARC™ has not assisted in the development and/or publication of these materials and does not endorse or recommend a particular study course or method. ARC™ suggests these references as a study tool only.

Husnu, B. & Gerhard, B. (2015). Handbook of Essential Oils Science, Technology, and Applications (2nd ed.). Boca Raton, FL: CRC Press. ISBN: 9781466590465

Battaglia, S. (2003). The Complete Guide to Aromatherapy (2nd ed.). Brisbane, Australia: International Centre of Holistic Aromatherapy. ISBN: 9780646428963

Bowles, J.E. (2004). Chemistry of Aromatherapeutic Oils (3rd ed.). Australia: Allen & Unwin. ISBN: 9781741140514

Buckle, J. (2015). Clinical Aromatherapy: Essential Oils In Healthcare (3rd ed.). London: Churchill Livingstone. ISBN: 9780702054402

Clarke, S. (2008). Essential Chemistry for Aromatherapy (2nd ed.). Edinburgh, UK: Churchill Livingstone. ISBN: 9780443104039

Cooksley, V. (2002). Aromatherapy: Soothing Remedies to Restore, Rejuvenate, and Heal. New York, NY: Prentice Hall Press. ISBN: 9780735203617

Kusmirek, J. (2002). Liquid Sunshine: Vegetable Oils for Aromatherapy. Somerset, England: Floramicus Publishers. ISBN: 9780954329501

Lis-Balchin, M. (2006). Aromatherapy Science: A Guide for Healthcare Professionals. London: Pharmaceutical Press. ISBN: 9780853695783

Marie, D. (2000). Making Aromatherapy Creams & Lotions: 101 Natural Formulas to Revitalize & Nourish Your Skin. North Adams, MA: Storey Books: ISBN: 9781580172417

Penoel, D. (1998). Natural Home Health Care Using Essential Oils. Essential Science Publishing. ISBN: 9782909531021

Price, S. & Price, L. (2012). Aromatherapy for Health Professionals (4th ed.). New York, NY: Churchill Livingstone. ISBN: 9780702035647

Rose, J. (1999). 375 Essential Oils and Hydrosols. Berkeley, CA: Frog Ltd. ISBN: 9781883319892

Salvesen, C. (2002). Aromatherapy for Natural Health and Beauty (3rd ed.). South Africa: Salvesen Publishers. ISBN: 9780620266994

Schnaubelt, K. (1998). Advanced Aromatherapy: The Science of Essential Oil Therapy. Rochester, VT: Inner Traditions International. ISBN: 9780892817436

Schnaubelt, K. (1999). Medical Aromatherapy: Healing with Essential Oils. Berkeley, CA: Frog Books. ISBN: 9781883319694

Tisserand, R. & Young, R. (2014). Essential Oil Safety: A Guide for Health Care Professionals (2nd ed.). New York, NY: Churchill Livingstone. ISBN: 9780443062414

Patton, K. & Thibodeau, G. (2015). Structure and Function of the Body (15th ed.). St. Louis, MO: Mosby/Elsevier. ISBN# 9780323341127

Valnet, J. (1982). The Practice of Aromatherapy. Rochester, VT: Healing Arts Press. ISBN: 9780852071434

Wayman, M. (1999). Aromatherapy: A Practical Guide. Israel: Astrolog Publishing House. ISBN: 9789654940528


Value to the Registered Aromatherapist (RA)

The ARC exam is compatible with and enhances aromatherapy clinical training and successful graduation from a program. It is an additional voluntary, optional professional registration that shows an aromatherapy program graduate has reached a professional level of competency and attained a core body of knowledge emphasizing safety issues.

Maintaining and renewing one’s RA status demonstrates to the general public and potential employers a continued commitment to ongoing education, professionalism, and public safety.

During the period that a person is registered, he or she must complete continuing education (CE). An RA can choose to submit new exam items (questions) as part of the required CE credits. If the CE requirement is not met, he or she must re-sit the exam after 5 years.

The ARC exam has been translated into Korean, Japanese, and most recently Chinese.

Here is the geographical breakdown of the 377 current and active RAs:

Active RAs as of 1/7/2016
CountryStateCount of RAs
BrazilSao Paulo1
Hong Kong1
South Korea246


Evidence of Competency

The ARC exam has been used in some states as evidence of competency given the absence of accredited credentials in the profession.

For example, the Oregon Higher Education Coordinating Commission (HECC) must approve all faculty teaching in Oregon and oversee all higher education institutions. All faculty teaching at an accredited institution in the U.S. must hold a degree higher than the one they teach. This is a requirement for all accredited Higher Education Institutions. Currently, there is no available PhD in Aromatherapy, so the HECC has approved the professional designation of a Registered Aromatherapist as a basis for an exception for faculty who cannot qualify by degree. This approval provides employment opportunities for Registered Aromatherapists as educators.


Evidence of Outcomes Assessment

The ARC exam has been used as evidence of competency and outcomes assessment by accreditation agencies. These agencies look at pass/fail rates for industry examinations to determine whether a school is meeting its published competencies.

Any school can publish the number and names of their graduates who have passed the RA exam.


The Value of Non-Membership

Neither schools nor membership organizations can issue professional certification or registration examinations with credibility. Independence from membership organizations ensures an impartial and unbiased body distinct from a body where members pay to belong, which is essential for objectivity and credibility from both within and without the industry.


Careers and Professional Enhancement

The RA registration may assist graduates to find placement and employment. Many employers are looking for external validation of competency, especially for graduates of unaccredited programs not subject to the same requirements and oversights of accredited programs.

Employers may or may not be industry members and may or may not, therefore, be familiar with any one school’s curriculum, safety standards, reputation, etc. The RA registration provides all aromatherapy program graduates and employers with a demonstrable validation of requisite knowledge, competency, and adherence to industry best practices.


ARC Financials

As a 501(c)(6), ARC has had tax-exempt status since 2007.

Filings of the 990-Ns can be viewed here:…&dispatchMethod=searchEpostcard&postDateFrom=&country=US&city=&searchChoice=ePostcard&indexOfFirstRow=0&sortColumn=ein&resultsPerPage=25&names=&zipCode=&deductibility=


ARC Feedback and Concerns

If you have suggestions and/or recommendations for the ARC Board to review, please submit a motion for the next board meeting (email: feedback@ or