TAPPI T844 Corrugated Package Testing

TAPPI 844 Determining Construction of Corrugated Boards

TAPPI 844 package testing is used to determine the normal base weight of corrugated board. As an ISTA and ISO 17025 certified lab, we realize the importance of T 844 corrugated board testing. Meeting the TAPPI 844 requirements can be difficult. We understand the challenges and guide companies through the process.

Keystone’s proven process helps avoid product launch delays. Our accurate test reports are delivered quickly. Keystone Package Testing partners with customers to achieve package compliance. We are in constant communication throughout the test process.

Request a quote to see why so many companies partner with Keystone Package Testing. Have a question about determining the construction of corrugated boards? Contact us and we will determine the best course of action.

Summary of TAPPI Corrugated Board Information

Standard TAPPI T844 testing determines the normal basis of weight in the components of corrugated shipping boxes and boards. Additionally, test specimens of corrugated fiberboard are treated with water. This is completed so that the component layers can be separated, dried, and weighed.

The goal of this method is to identify the probable marketing grade under which the papers were likely sold. Not to be confused with determining the exact basis weights of the papers comprising a corrugated material.

The examination is performed on a single sample due to limitations in the available material. With this intention, results can be affected by any damage or abrasions of the surface layers. Ideally, the sample is taken from a flat area of the board away from score lines.

Scope of TAPPI 844 Corrugated Board Testing

This method is applicable to all types of corrugated fiberboard. However, the surface layers of the specimen should be free from any damage or abrasions. This may lead to loss of fiber or otherwise impact the test results.

Since the board is immersed in water, there is typically no need to condition specimens before testing. In some cases, the results are checked by summing the measured weights of each component. Next, they are compared to the initial basis weight of the combined sample.

Significance of TAPPI 844 Construction of Corrugated Board Testing


Any conditioning of the specimens are conducted according to TAPPI T402 “Standard Conditioning and Testing Atmospheres for Paper, Board, Pulp Handsheets, and Related Products.


During the TAPPI T844 procedure, the board is carefully cut to a known area. Then, corrugated boards are cleaned with edges perpendicular to the faces of the corrugated cardboard. Different sizes are used for ease of calculation, balanced against the amount of material available for testing. Larger specimen sizes will reduce the impact of measurement error in the weighing stages relative to the final result.

Next, the sample is immersed in water long enough to cause the component layers to separate. While the papers are still wet, the adhesive is carefully removed from the layers.

Immediately after, samples are removed from the water and oven-dried and reconditioned until equilibrium is reached. Lastly, each component is weighed, and a report is written.

Labs and testing sites are usually called to determine what grades were used in the construction of a corrugated board sample. This determination is mostly used for sales and marketing purposes and does not provide information of the board’s strength or quality. TAPPI T844 can be used to provide guidance to manufacturing facilities to make similar products.

Test Report

The report details may include general information such as:

  • Date, time, testing location, and test engineer
  • Any conditions used
  • Details of the package and other characteristics
  • Number of failures
  • The nominal grade for each layer of the corrugated board is identified
  • The nominal flute sizes, type, and a number of corrugated flutes per foot
  • Each medium layer in the board structure

Expert TAPPI 844 Corrugated Box Package Testing

Keystone has a full scope of expertise including temperature validation, vibration, and cold chain. We can accommodate flexible and rigid packages of all sizes, including large pallets. Our team strives to give our customers more time and energy on product development instead of testing. 

Ready to get started? Request a quote to see why so many companies work with Keystone to achieve their corrugated package testing needs.


For more information on other TAPPI package test standards, please visit the following links:


Interested in the EMC/EMIclimaticdynamicshielding effectiveness, or IP Code testing of a product? Follow the corresponding links or www.keystonecompliance.com for more information.