Our MSDS files are located here - http://www.envexp.com/msds.

Most of our certificates of analysis are found at the following link - http://www.envexp.com/coa. If you do not find the lot number listed under the appropriate section please email info@envexp.com with the lot number and catalog number that you need and we will be happy to provide the information you need.

Standard Methods 5210B (2001) section 5. e. deals with the nitrification inhibitor. It instructs that the amount of seed used should be sufficient to achieve GGA results in the range of 198 ± 30.5 mg/L. For that reason we do not list different true values and acceptance ranges for BOD vs. cBOD.

When using the GGA solution that has been prepared according the method, you should have 6 mL of this standard added into a 300 mL BOD bottle. You will add whatever volume of seed is needed from your seed source to achieve the proper oxygen depletion and the remainder of the volume will be done with dilution water.

The BOD value of any substance should never be greater than the COD value within the margin of error for each test. If you have results that seem to indicate otherwise you are probably experiencing some sort of negative interference with the COD analysis or a positive contaminant with the BOD analysis.

Yes, a certificate of analysis is available. If one did not come with your product please contact info@envexp.com with the your lot number and a COA will be provided to you.

This solution is made exactly as specified in Standard Methods. There is no preservative available for the GGA standard. The vials are sterilized via autoclave after being filled so that no bacterial activity will degrade the components in the vials.

This standard can be used to check the calibration of your analytical procedures and equipment. It comes with a certified value and acceptance range for each of the parameters listed. Simply measure out the amount of standard as required by the test method and analyze it exactly as you would a sample.

The G:Ga standards do not require refrigeration of any kind. The MSDS requires storage capped at room temperature.

There are any number of things that could cause out of range G:GA values. Dilution water quality, strength of seed, incubation temperature and probe calibration are some of the more likely causes. I would be glad to discuss some scenarios and trouble shooting with you. Email me at DavidS@envexp.com or call 1-843-576-1133 and we can go over the process.

This product is not available to sample.

This product has an expiration date of 1-year from date of manufacture.

The pH of all samples for the BOD test should fall within a value of 6.5 - 7.5. Your blanks, GGA, and seed should be analyzed as-is as the method does not call for any pH adjustment of these solutions.

Standard Methods 5210 states that the true value of the GGA standard to be 198 mg/L with an acceptance range of +/- 30.5 mg/L. To comply with the method you should always use this range. This standard as well as the other GGA standards we offer meet the Standard Methods requirements.