Calcium chloride specifications and test reporting
Adapted from the vaprecision model calcium chloride test
Specifications
This test method was developed in the 1950’s and has been widely accepted by the flooring industry as a quantitative measure of slab moisture.
This test works by a change in weight of moisture-absorbing anhydrous calcium chloride and represents the amount of moisture transmitting out of a large concrete surface area. The value expressed by this test is called POUNDS. Pounds are the equivalent weight of the water that is emitted from a 1000 square foot concrete slab area in a 24 hour period.
All concrete surfaces emit some amount of moisture, in the form of a vapor, regardless of the concrete’s age or grade level. The majority of floor covering material manufactures and specification institutions recognize this test and indicate that it is safe to install a floor if the slab emission is 3.0 pounds or less.
The proper number of tests needed to determine the potential of floor covering installation bond success, is a minimum of three tests for the first 1000 square feet. Add one test for each additional 1000 square feet.
The test requires the use of a gram weight scale with a gradation to 1/10 of a gram. If you can not obtain this type of scale, please contact vaprecision for information about obtaining one.
This test has been scientifically developed for accuracy. The configuration of the dome and the type and amount of calcium chloride has been designed to reduce the variability common to other calcium chloride test kits.
The butyl rubber gasket material is pre-installed for accuracy and to make installation easier. DO NOT make contact with gasket as it is extremely sticky and difficult to remove from skin or clothing.
This test is valid for below, on, and above grade surfaces. DO NOT conduct this test unless the slab environment is similar to what the finished flooring will be maintained in. Meaningful results are obtained when the building environment represents a normal climate.
Please refer to label on protective wrapper for important safety precautions when using anhydrous calcium chloride materials.
Any Questions regarding concrete moisture vapor emission should be directed to VAPRECISION Customer Service Center at 1(800) 449-6194 or www.vaportest.com.
Reporting results
A. each test report should cite captioned recipients, including:
1. Owner
2. Agent
3. Architect / Engineer
4. General Contractor
5. Flooring Contractor
B. detailed information for accountability, such as:
1. Complete company name and primary contact of test performer.
2. Place, date, time, and list of other trade-groups in progress.
3. Types of testing instrument employed and how it was used.
4. Specification from flooring material manufacturer on moisture.
5. A statement of justification for employing the type of test instrument.
C. an organized data sheet of test deployment parameters, including:
1. A floor plan of building with clearly marked test locations.
2. A written description of test placement quality control practices.
3. Temporal tests, such as calcium chloride, must include:
a. Test number and location.
b. Starting date, time and beginning weight.
c. At minimum, a written estimation of building temperature.
d. Stopping date, time and ending weight.
e. computed pounds of emission, including equations.
A meeting should then be held with all involved parties so that everyone knows the meaning of the date and the options available to tem. Testing is done to determine the acceptability of the current vapor emission condition. But testing is really performed in order that future problems with failure can be avoided.
Lack if testing procedures executed in a properly conditioned environment is part of the reason why most floor failures occur. Unfortunately, many new construction projects do not offer a properly controlled environment prior to installation or the time necessary for water of convenience to have evacuated from slab.