Hydrometers
Hy
Application/Selection Guide
How to Read a Hydrometer
Plain Form hydrometers do not have a built-in
thermometer; use a separate thermometer to
measure the temperature. . . . . . . . . . . . . . . . . . . . . . . . . . 1009–1014
1. Pour your sample into a smooth, clear cylinder or jar that is dry
or well rinsed with a portion of the sample.
Combined Form hydrometers have a thermometer
built into the body or stem to measure the temperature
of the sample. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1010, 1012–1013
3. Immerse the hydrometer in the liquid to a point slightly below
the place where it naturally floats. Make sure the hydrometer
and liquid are at rest and free of air bubbles.
Specific Gravity is the standard scale for what a
hydrometer measures. Specific gravity is the ratio
of the density of your sample at 60°F (15.6°C) to the density
of water at 60°F (15.6°C). . . . . . . . . . . . . . . . . . . . . . 1009–1011, 1014
API scale hydrometers are selected by the American
Petroleum Institute (API), the United States Bureau of Mines,
and the National Institute of Standards and Tech­nology
(NIST) as the standard scale for petroleum products. . . . . . . . . 1012
Baumé hydrometers are used for liquids heavier than
water, such as syrups . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1011
Brix Scale hydrometers are used by the sugar industry. The
degrees of the scale are equal to the percentage of sucrose
by weight at standard temperatures.. . . . . . . . . . . . . . . . . . . . . . 1013
Salt hydrometers are graduated in % saturation or % by
weight of salt in solution. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1012
Alcohol (Tralle and Proof Scales) hydrometers measure
directly in percentage ethyl alcohol by weight in water from
0 to 100%. The Proof scale indicates the proof of alcohol from
0 to 200 proof. Proof is twice the percentage of alcohol by
volume in solution. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1012
Soil hydrometers determine the specific gravity of a
suspension, enabling the percentage of particles of a
certain equivalent particle diameter to be calculated. . . . . . . . . 1014
2. Make sure that your sample is thoroughly mixed before testing.
4. Measure the temperature of the sample. Ideally, the sample
temperature should be equal to the temperature standard of the
hydrometer, generally 60°F (15.6°C). If temperature differences
are unavoidable, correction tables can help to adjust readings—
call our Application Specialists for information.
5. Take your reading at the point where the surface of the
liquid crosses the hydrometer.
TECHNICAL info!
Degrees Baumé = 145 –
145
sp gr 60°F/60°F
141.5 Degrees API = – 131.5
sp gr 60°F/60°F
Cole-Parmer is proud to offer
nonhazardous and environmentally
friendly, mercury-free alternatives!
As of July 1st 2008, Illinois state law prohibits the sale or
distribution of mercury-containing devices worldwide.
Ensure the accuracy of your hydrometer!
T-17107-00 NIST-traceable calibration
with data for hydrometers
H-B Instrument DURAC ® Specific Gravity Glass Hydrometer Kit
Specific gravity hydrometers measure the ratio of the density
of a sample compared to the density of pure water at the
same temperature. The temperature standard is 60°F (15.6°C).
These hydrometers are plain form, individually serialized, and
include a multilanguage statement of accuracy supplied by the
manufacturer.
This kit contains eight specific gravity glass hydrometers from
0.700 to 2.000 in range and 300 mm in length and one EnviroSafe® total immersion thermometer from –30 to 120°F
in range and 300 mm in length—all conveniently stored
in a foam-lined hard storage case.
Catalog number
T-08297-41
Range
Divisions
Length
Specific gravity hydrometers, plain form
0.700 to 0.810
0.800 to 0.910
0.001
300 mm
0.900 to 1.000
1.000 to 1.220
0.002
1.200 to 1.420
1.400 to 1.620
0.001
300 mm
1.600 to 1.820
1.800 to 2.000
0.002
Thermometer, total immersion
–30 to 120°F
2°F
300 mm
Price
08297-41
T-17107-00 NIST-traceable calibration with data for hydrometer
US Toll-free: 800-323-4340
•
Outside the US: 1-847-549-7600
•
www.coleparmer.com
Canada 800-363-5900 • India 91-22-6716-2222 • UK 0500-345-300
1009
KEY INFORMATION
Types of Hydrometers