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Examination Procedures for Price Verification

NIST Handbook 130 - Uniform Laws and Regulations in the areas of Legal Metrology and Engine Fuel Quality

In 1993 the National Institute of Standards and Technology (NIST), in conjunction with the National Conference on Weights and Measures (NCWM), developed the Examination Procedure for Price Verification (EPPV) to respond to public concern about price accuracy in retail stores. More than 500 retailers, consumer representatives, and state and local weights and measures officials participated in the development of this procedure. The Examination Procedure for Price Verification was adopted by the NCWM in 1995, and is published in NIST Handbook 130.

Frequently Asked Questions

  1. What is the NIST EPPV?
    The NIST EPPV is an inspection procedure that provides regulatory officials and other interested parties with the test procedures, enforcement practices, and other tools necessary to monitor and evaluate the pricing practices of retail stores.
  2. Is it a law or regulation?
    No, the NIST EPPV is an inspection procedure. The results of an inspection conducted according to the EPPV must be evaluated for compliance with state or federal laws and regulations.
  3. Does NIST regulate or enforce pricing accuracy?
    No, NIST is not a regulatory agency. The Federal Trade Commission (FTC) is the federal agency with regulatory jurisdiction over most advertising and pricing practices. Many states also have laws and regulations that prohibit inaccurate or deceptive advertising and pricing practices.
  4. Why do we need an EPPV?
    Consumers want to be confident that the price at which a product is advertised or displayed is the price they will be charged at the check-out counter. The NIST EPPV was developed as a method that regulatory officials and other parties may use to help ensure that consumers are charged the correct price for items they purchase.
  5. How does it work?
    The NIST EPPV utilizes "randomized" and "stratified" sampling plans that look at products throughout a store in order to evaluate how well the store is maintaining price accuracy. The EPPV establishes procedures for comparing the price at which products are advertised or displayed to the price charged at the check-out counter. These procedures may be used with any type of check-out process, from manual entry by the cashier to fully automated scanner systems.
  6. Does it apply to all retail stores?
    The NIST EPPV applies to all retail stores that sell products, including but not limited to grocery, hardware, general merchandise, drug, automotive supply, convenience, and warehouse club stores.
  7. Does the NIST EPPV allow stores to have pricing errors?
    Under the NIST EPPV, a retail store "fails" an inspection when more than 2 % of the products tested are advertised or displayed at a price that is different from the price charged at the check-out counter. These pricing errors may be either over- or under-charges, and are not always against the consumer.
  8. Does this mean stores are allowed to have 2 % of their products incorrectly priced?
    It is inaccurate to say that stores are allowed to have 2 % of their products incorrectly priced. Federal law prohibits "unfair or deceptive acts or practices in or affecting commerce."1 The 2 % error rate established in the NIST EPPV is a guideline to help regulatory officials evaluate whether or not a retail store has good pricing practices. This should not be interpreted to mean that any errors found are "acceptable" or do not need to be corrected.
  9. What does it mean if a store "passes" inspection?
    If a store passes inspection under the NIST EPPV, that means that on that day at least 98 % of the products tested were advertised or displayed at the same price that was charged at the check-out counter.
  10. Are regulatory agencies required to follow the NIST EPPV?
    No, although the FTC and many state agencies do.
  11. Are regulatory agencies required to permit 2 % of products to be inaccurately priced?
    No. The 2 % error rate provided in the NIST EPPV is merely a guideline to assist regulatory officials with evaluating the overall quality of a store's pricing practices. Depending on the type and pattern of errors found, many regulatory agencies would have the authority to take enforcement action against a store even if the store had an error rate of less than 2 %.
  12. Where can I get a copy of the NIST EPPV?
    The NIST EPPV is published in NIST Handbook 130, Uniform Laws and Regulations in the areas of legal metrology and engine fuel quality. The EPPV may be viewed and downloaded from the web. Alternatively, copies of NIST Handbook 130 may be purchased from the NCWM.

    115 U.S.C. Sec. 45(a)(1).

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