Opened 3 weeks ago

#5816 new enhancement

Jackson turbidity unit

Reported by: William Hess Owned by:
Priority: minor Milestone:
Component: organization Keywords: JTU


UCUM Board needs to provide input on this. A Jackson Turbidity Unit is an arbitrary unit of turbidity originally based on a suspension of specific type of silica with the turbidity measured in a Jackson Candle Turbidimeter. This has been replaced by the nephelometric turbidity unit (NTU). See Also, There are several practical ways of checking water quality, the most direct being some measure of attenuation (that is, reduction in strength) of light as it passes through a sample column of water. The alternatively used Jackson Candle method (units: Jackson Turbidity Unit or JTU) is essentially the inverse measure of the length of a column of water needed to completely obscure a candle flame viewed through it. The more water needed (the longer the water column), the clearer the water. Of course water alone produces some attenuation, and any substances dissolved in the water that produce color can attenuate some wavelengths. Modern instruments do not use candles, but this approach of attenuation of a light beam through a column of water should be calibrated and reported in JTUs. See

This new concept is needed to support the U.S. Food and Drug Administration Pharmaceutical Quality Chemistry Manufacturing and Control (PQ/CMC) initiative. Please see, which in part, states:

"PQ/CMC is a term used to describe manufacturing and testing data of pharmaceutical products. PQ/CMC encompasses topics such as drug stability, quality specification, batch formula, and batch analysis, which are important aspects of drug development. PQ/CMC plays an integral part in the regulatory review process and life cycle management of pharmaceutical products. The development of a structured format for PQ/CMC data will enable consistency in the content and format of PQ/CMC data submitted, thus providing a harmonized language for submission content, allowing reviewers to query the data, and, in general, contributing to a more efficient and effective regulatory decision-making process by creating a standardized data dictionary.

The impetus for this standardization effort was the provisions from the 2012 Food and Drug Administration Safety and Innovation Act (Pub. L. 112-144), which authorized the Agency to require certain submissions to be submitted in a specified electronic format. PQ/CMC standardization supports FDA's regulatory needs in receiving structured and standardized data in pharmaceutical quality and includes two objectives: (1) To standardize the pharmaceutical quality data that is currently received by FDA in eCTD Module 3 from the sponsoring organizations, and (2) to use these structured elements and develop a FHIR data exchange solution."

Change History (0)

Note: See TracTickets for help on using tickets.