BOSS Refractometer GR-100 Portable 0-100% w/w Glycerin Refractometer - Measures Concentration and the Freeze Points in ºF and ºC

For Glycol Antifreeze, please consider our other units designed specifically for Glycol (Ethylene and Propylene) Glycols.

Concentration and Testing

• Fire suppression systems use a closed loop to isolate freeze-proofed areas. A check valve keeps antifreeze from returning to the main sprinkler system. Glycerin offers highest antifreeze protection at a 70 percent concentration by weight. At this level, pipes are protected against freezing to minus 36 degrees Fahrenheit. Above this concentration glycerine will begin to freeze at higher temperatures: pure glycerin begins to solidify near 32 degrees F. Check with your local Fire Marshal to find the concentration required for your climate. Manufactures offer premixed glycerin solutions though you can blend your own mixture using food-grade glycerin and distilled water. Open the filling inlet to load the antifreeze into the sprinkler system. Use the GR-100 refractometer to test that the glycerin solution is identically concentrated at the filling inlet and at the drain valve at the furthest point in the sprinkler line. Retest the concentration level during the annual inspection of your sprinkler system.

  Go to the NFPA's website for the latest on the current standards:  http://www.nfpa.org/antifreeze

But don't take our word for it...

Testimonial:

"I've had an opportunity to check the use and accuracy of the GR-100 refractometer I ordered and found it to be easy to use and read, and it works exactly as it is designed to. The price is so much better than the electrical/digital models I saw everywhere else that I feel you're offering this device at an excellent price, especially since it gives just as accurate a reading as the digital models.

So, thanks for a good product at an excellent price."

Jim B.  11/23/17

FAQ: Frequently Asked Questions About the GR-100 Glycerin Refractometer

1. What is the GR-100 glycerin refractometer used for?

The GR-100 glycerin refractometer measures the concentration of glycerin in water-based solutions. It is designed for applications such as testing glycerin-based antifreeze in fire sprinkler piping and checking glycerin concentrations in other compatible water-based mixtures. Measuring concentration helps technicians evaluate whether a solution meets the requirements specified for its intended application.

2. Can the GR-100 test glycerin antifreeze in fire sprinkler systems?

Yes. The GR-100 is designed to measure glycerin concentration in water-based antifreeze solutions, including those used in fire sprinkler systems. Technicians can take a sample and measure its glycerin concentration to help assess the condition of the antifreeze solution. Always follow applicable fire protection codes, the system manufacturer’s instructions, and the antifreeze manufacturer’s testing procedures.

3. Does the GR-100 measure glycerin concentration from 0% to 100%?

Yes. The GR-100 has a glycerin concentration scale ranging from 0% to 100%. This broad measurement range allows users to test a variety of glycerin-water mixtures. Its stated resolution is 0.5%, with a stated accuracy of ±1.0%. Confirm the applicable concentration scale and reporting basis in the instrument’s user guide before interpreting results.

4. Can the GR-100 determine the freeze point of glycerin antifreeze?

The GR-100 user guide provides a reference for relating glycerin concentration to the freezing point of glycerin-water solutions in degrees Fahrenheit and Celsius. Measure the sample’s concentration, then consult the guide to interpret the corresponding freeze point. For fire sprinkler applications, verify that the solution meets the specific requirements for the system and product being tested.

5. How do you use a glycerin refractometer?

To use the GR-100, first calibrate the instrument according to its user guide. Place a small sample of the glycerin-water solution on the measuring surface using the supplied pipette, then take the reading according to the instrument’s instructions. Record the result and consult the user guide if you need to determine the corresponding freeze point. Clean the measuring surface after testing to prevent contamination between samples.

6. How do you calibrate the GR-100 glycerin refractometer?

The GR-100 is supplied with a calibration screwdriver. Its product instructions specify distilled water for calibration, with water corresponding to a 0% glycerin reading. Follow the supplied user guide for the complete calibration procedure, including the correct adjustment method and conditions.

7. What is the difference between a glycerin refractometer and a glycol refractometer?

A glycerin refractometer is designed for glycerin-water mixtures, while a glycol refractometer is designed for specific glycol-based fluids, such as ethylene glycol or propylene glycol. The instruments use different measurement scales and calibration relationships. The GR-100 is intended for glycerin in water and should not be used to determine glycol concentration unless the instrument is specifically validated for that fluid.

8. Can I use the GR-100 to test propylene glycol or ethylene glycol antifreeze?

No. The GR-100 is designed for glycerin-water solutions, not for measuring ethylene glycol or propylene glycol antifreeze. Glycol-based fluids require a refractometer with the appropriate glycol-specific scale. Using the wrong instrument can produce misleading concentration or freeze-point interpretations. Choose a refractometer designed for the fluid you need to test.

9. What accuracy and resolution does the GR-100 offer?

The GR-100 has a stated measurement resolution of 0.5% and a stated accuracy of ±1.0%. Resolution describes the smallest increment shown on the scale, while accuracy describes the expected measurement deviation under the applicable conditions. For critical fire protection decisions, consider the instrument’s stated accuracy and follow the required testing and verification procedures.

10. What comes with the GR-100 glycerin refractometer?

The GR-100 includes the refractometer, a protective plastic carrying case, a calibration screwdriver, a sampling pipette, and a user guide. These accessories help users calibrate the instrument, collect a sample, take measurements, and interpret results. Check the current product listing for the exact package contents.

11. Can the GR-100 test premixed glycerin antifreeze?

Yes. The GR-100 can measure compatible premixed glycerin-water antifreeze solutions within its measurement range. The result depends on the actual concentration of the sample, not simply the product’s label. Follow the antifreeze manufacturer’s instructions for sampling and interpreting concentration results.

12. How often should glycerin antifreeze in a fire sprinkler system be tested?

Testing frequency depends on the applicable fire protection requirements, the system design, the antifreeze manufacturer’s instructions, and the authority having jurisdiction. Periodic testing can help identify changes in solution concentration. Follow the inspection and maintenance requirements applicable to your particular system rather than relying on a generic testing schedule.

13. Is the GR-100 suitable for professional fire sprinkler inspections?

The GR-100 is designed for measuring glycerin concentration in water-based solutions and can support technicians performing antifreeze testing. Whether it is suitable for a particular inspection or compliance procedure depends on the required measurement accuracy, approved testing method, system requirements, and applicable codes. Verify those requirements before relying on the instrument for compliance decisions.

14. What is the difference between glycerin, glycerine, and glycerol?

Glycerin, glycerine, and glycerol are commonly used names for the same chemical compound. These terms frequently appear in product descriptions, technical documents, and searches for glycerin antifreeze testing equipment. The GR-100 is intended for measuring glycerin in water-based mixtures.

15. Where can I buy a GR-100 glycerin refractometer?

The GR-100 glycerin refractometer is available from National Industrial Supply (NISupply). It provides a dedicated 0–100% glycerin measurement scale for users who need to check glycerin-water solutions. See the product listing for current pricing, availability, specifications, and included accessories.

National Industrial Supply 
30777 Rancho California #891420
Temecula, CA 92589, USA
Sales: 310.748.6858
Website: www.nisupply.com  -  E-mail: nisupply@gmail.com