To obtain a numerical value indicating the rate of moisture vapor escaping from a concrete floor surface in a 24 hour period. The results indicate whether or not a surface is suitable to receive floor coverings, coatings or cement toppings. The test may be used for testing vapor control coating products before and after application as a field quality control test.
Developed by the US Rubber Manufactures Association (RMA) in the 1950’s, this test method was released as ASTM F1869 in late 1998 and remains the most widely used test method for testing.
All concrete substrate testing requires temperature and humidity of the building to be sustained for accurate results. Results obtained before a controlled environment is achieved may be used for reference only, with future testing to be performed under ideal conditions. Do not install near windows or direct sunlight.
Begin testing at the same temperature and humidity expected during normal building use. If this is not possible, ASTM F1869 allows for test conditions to be 65ºF to 75ºF and 40% to 60% relative humidity this needs to be maintained for 48 hours prior to and during testing. The use of a temperature and humidity data logger may be used to verify conditions during testing. Contact our technical department for details.
The amount of tests required is a simple calculation of the total square feet to be floored, at all grade levels. ASTM F1869 guidelines state three (3) tests for the first 1,000 square feet and one (1) additional test for each additional 1,000 square feet thereafter.
Examples: 1,000 ft² = 3 tests | 10,000 ft² = 12 tests
Test Area/ Preparation
Clean a 20” x 20” area free of flooring, coatings, patching cements, adhesive residue and expose a clean concrete surface. To speed the process, a dustless grinder may be used to clean the surface. Do not use acid etching, water, strippers or clean sweeping agents.
Protect all test sites from damage for 60 to 72 hours.
The final test results are reported as a quantity of moisture expressed as the weight of condensed gas (liquid) in pounds that is emitted over 1,000 ft² area during a 24 hour period.
Results may vary from 0.00 to 30.00 /1,000 ft²/24 hours.
Flooring and Adhesive Requirements
The industries most stringent vapor requirement is 3.0 lbs. or less. Verify each manufacturer’s tolerance before installation of the flooring product.
AMT kits are manufactured with high quality components and offer unlimited shelf life with no expiration date.
o Thick 30 – 35 mill construction
o Excellent crush resistance
Calcium Chloride Salt & Dish
o Salt Purity up to 97%, non-recycled
o Factory weighed, vapor tight packaging
o Factory Installed Adhesive
o Will not dry or harden
o Adhesion to virtually any surface
Calculation Formula Example
Use our online CC Moisture Calculator or use the following example: : 5.8 gram weight gain at 68 hours and 15 minutes: