Inside this Issue

Laboratory Metrology:

Measure for Measure ‐ Does Accuracy

Matter to You? 1

Training and Events Calendar 2

Employee News:

Back to the Vikings 7

1

Volume 7 Issue 4

July 1, 2016

OFFICE OF WEIGHTS

AND MEASURES

General Inquires: (301) 975‐4004; 

e‐mail: owm@nist.gov

Acting Office Chief, Georgia Harris: 

e‐mail: gharris@nist.gov

Newsletter Editor: Linda Crown;

(301) 975‐3998; 

e‐mail: linda.crown@nist.gov

HAPPY

BIRTHDAY

AMERICA

Measure for Measure –

Does Accuracy 

Matter to You?

Byline:

Elizabeth J. Gentry, NIST Office of Weights and Measures U.S. Metric Coor‐

dinator, and

Georgia L. Harris, NIST Office of Weights and Measures, Laboratory Metrol‐

ogy Program Leader

Accuracy in Measurement Results 

Many decisions are based on accurate measurement results. Should med‐

icine be prescribed for high cholesterol or high glucose? Should a measur‐

ing instrument or standard be adjusted to meet tolerances? Is there really

global warming or climate change? Answers to these questions are all

based on measurement results and as a patient, scientist, citizen, or policy

maker, we make assumptions about the accuracy of measurement results

we receive in reports and calibration certificates. We assume they are good,

that is right, or more correctly accurate. Note that accuracy is often defined

as hitting the center of the target or a true value. A colleague of the authors

was noted to regularly say “the only true value is on a sign above a hardware

store.” However, measurement users often trust the accuracy of measure‐

ment results they receive, usually without question. Users of measurement

results believe that the results are of good quality and are good and right.

However, a measurement result alone is incomplete without some assess‐

ment and measure of reported uncertainty associated with the result. Peo‐

ple can estimate the temperature outside on a warm spring day within a

few degrees based on their experience and scientists can estimate the tem‐

perature in a laboratory within a degree based on their experience working

in environmentally controlled spaces. However, using a thermometer, we

first hope that it is accurate and giving us the correct or right temperature,

but then we must consider the resolution of the standard. Is the readability

of the thermometer 1 °C, 0.1 °C, or 0.01 °C. Our confidence in the results,

if they are right, will be dependent upon the readability or resolution of the

standard or measuring instrument. Our confidence should not be based

on the fact that a calculator or spreadsheet will give us a calculated value

to 15 decimal places when the resolution or uncertainty is only to 1 or 2

decimal places!

Repeatability of the instrument or standard is also a variable of concern.

How often do people naturally repeat measurements to get a sense of

whether multiple values agree? Even simple measurements such as step‐
W&M Connection 2 Volume 7 Issue 3

Training and Events

Calendar 

2016

Registration for training in the NIST Office of

Weights and Measures is handled by Yvonne

Branden at yvonne.branden@nist.gov.

Course descriptions can be viewed on the Office

of Weights and Measures website at ‐ 

http://www.nist.gov/pml/wmd/calendar.cfm

and clicking on the name of the course. 

July 13 (2 hr)

Webinar ‐ NISTIR 7383, SOP 19 Parts 1 & 2*

10:00 a.m. ‐ 12:00 p.m.

Class No. 5452

July 24 ‐ 28 (5 days)

National Conference on Weights and Measures 101st

Annual Meeting

Denver, CO

info@ncwm.net

August 2 (1 hr)

Webinar ‐ Information Hour ‐ Quality Management

System

2:00 p.m. ‐ 3:00 p.m.

Class No. 5376

August 8 ‐ 12 (5 days) (FULL)

Fundamentals of Metrology

Class No. 5417

NIST/Gaithersburg, MD

August 11 (2 hr)

Webinar ‐ Contract Review

2:00 p.m. ‐ 4:00 p.m.

Class No. 5383

August 22 ‐ 26 (5 days)

Handbook 133 ‐ Chapter 4, Dimensional Measure‐

ment

Class No. 5401

NIST/Gaithersburg, MD

August 23 ‐ 24 (2 days)

NTEP Weighing Sector Meeting

Denver, CO

www.ncwm.net

August 25 (2 hr) 

Webinar ‐ Document Control and Record Keeping

2:00 p.m. ‐ 4:00 p.m.

Class No. 5384

September 11 ‐ 15 (5 days)

WWMA Annual Meeting

Honolulu, HI

www.ncwm.net

September 13 ‐ 14 (2 days)

NTEP Grain Analyzer Sector Meeting

Kansas City, MO

www.ncwm.net (continued on pg 3)

ping on a scale to get an idea of one’s weight (where we always hope the

second or third reading will be lower), inserting a kitchen thermometer into

the turkey to see if it has reach the desired temperature, or checking our

mileage over time to calculate fuel efficiency for our vehicles, are all com‐

mon in daily life. 

In a calibration laboratory, the assignment of uncertainty to the measure‐

ment result is a rigorous, documented, and validated process that is as‐

sessed nearly as often as the measurement results themselves.

Measurement scientists often use internationally accepted procedures to

obtain standardized measurement results, and use the Guide to the Expres‐

sion of Uncertainty in Measurement1 as a guiding document on evaluating

and reporting measurement results and their associated uncertainties. 

The readability or resolution and repeatability of the measurement results

give us a sense of confidence, or lack of confidence, and is a measure of the

uncertainty associated with the measurement results. It is a wise practice

to ask for the measurement uncertainty and use it as an assessment of the

quality of a measurement result and its precision. Uncertainty values pro‐

vide a measure of confidence in the measurement result; it provides a quan‐

tification of the boundaries or limits within which the measurement result

should agree with a true quantity value.

Accuracy in Terminology and Communications

Once accurate measurement results and associated uncertainties are avail‐

able, they need to be communicated. Communications may be in a news‐

paper, on television, in a scientific paper, or on a calibration certificate.

Thus, accuracy in our words and measurement results is also critical. As in

the case of measurement uncertainties, measurement scientists also have

guiding documents to help standardize communications. In this case, the

International Vocabulary of Metrology (VIM)2 is used as the guiding docu‐

ment on terms used with measurement and calibration results. Uses of

terms like accuracy, traceability, uncertainty, and reference standards all

have very specific meaning to measurement professionals and should be

used by all scientists. 

For example, the VIM defines accuracy, as related to a measurement result,

as:

2.13 (3.5) 

measurement accuracy 

accuracy of measurement 

accuracy 

closeness of agreement between a measured quantity value and a

true quantity value of a measurand 

NOTE 1 The concept ‘measurement accuracy’ is not a quantity and

is not given a numerical quantity value. A measurement is said to

be more accurate when it offers a smaller measurement error. 

1 Evaluation of Measurement Data — Guide to the Expression of Uncertainty in

Measurement, JCGM 100:2008 GUM 1995 with minor corrections, available free

at: http://www.bipm.org/en/publications/guides/gum.html, 2015‐01‐12. 

2 International Vocabulary of Metrology – Basic and General Concepts and Associ‐

ated Terms (VIM 3rd edition) JCGM 200:2012 (JCGM 200:2008 with minor correc‐

tions), available for free: http://www.bipm.org/en/publications/guides/vim.html,

2015‐01‐12.
W&M Connection 3 Volume 7 Issue 4

September 14 (1 day)

NTEP Measuring Sector Meeting

Kansas City, MO

www.ncwm.net

September 19 ‐ 22 (4 days)

NEMAP**

Class No. 5408

Concord, NH

September 20 ‐ 21 (2 days)

NTEP Measuring Sector Meeting

Denver, CO

www.ncwm.net

September 27 (2 hr)

Webinar ‐ Introduction to the ADDIE Model

2:00 p.m. ‐ 4:00 p.m.

Class No. 5439

September 29 (2 hr)

Webinar ‐ State Laboratory Annual Submission

Process

2:00 p.m. ‐ 4:00 p.m.

Class No. 5443

October 3 ‐ 5 (3 days)

Central Weights and Measures Association (CWMA)

‐ Interim Meeting

St. Charles, MO

Contact: Sherry Turvey at

sherry.turvey@kda.ks.gov

October 3 ‐ 6 (4 days)

SWAP**

Class No. 5409

Austin, TX

October 11 (2 hr)

Webinar ‐ Introduction to Blooms Taxonomy and

Learning Objectives

2:00 p.m. ‐ 4:00 p.m. 

Class No. 5440

October 17 ‐ 20 (4 days)

MidMAP**

Class No. 5410

Columbus, OH

October 20 (2 hr)

Webinar ‐ Internal Auditing Best Practices

2:00 p.m. ‐ 4:00 p.m.

Class No. 5385

October 24 ‐ November 4 (10 days)

Mass Metrology Seminar

Class No. 5386

NIST/Gaithersburg, MD

2017

January 19 (2 hr)

Webinar ‐ Documenting Traceability and Calibration

Intervals

2:00 p.m. ‐ 4 p.m.

Class No. 5444

(continued on pg 4)

NOTE 2 The term “measurement accuracy” should not be used for

measurement trueness and the term “measurement precision”

should not be used for ‘measurement accuracy’, which, however, is

related to both these concepts. 

NOTE 3 ‘Measurement accuracy’ is sometimes understood as close‐

ness of agreement between measured quantity values that are

being attributed to the measurand.

According to the VIM, measurand is “the quantity intended to be meas‐

ured.” But, it becomes obvious that when comparing measurement results

from one laboratory or between countries, scientists must be able to talk

about the same thing. Thus, the use of standardized definitions is essential.

As the reader can see, even the definition of accuracy requires explanatory

notes! Use of standardized terminology can help avoid a Tower of Babel Ef‐

fect3 when communicating measurement results!

Accuracy in Presenting Units, Symbols, and Measurement Results

Finally, measurement results must be communicated with proper quantities,

units, and symbols. In fact, many countries adopt the International System

of Units (SI) as the reference basis for measurement results. Again, there is

a standardized document for referencing and presenting measurement

units, symbols, and results.4 The U.S. Metric Program of the National Insti‐

tute of Standards and Technology (NIST), Office of Weights and Measures

(OWM), helps implement the national policy to establish the SI (Interna‐

tional System of Units, commonly known as the metric system) as the pre‐

ferred system of weights and measures for U.S. trade and commerce. It

provides leadership and assistance on SI use and conversion to federal agen‐

cies, state and local governments, businesses, trade association, standards

development organizations, educators, and the general public. Together

NIST Special Publication (SP) 330, The International System of Units (SI), and

NIST SP 8115

, Guide for the Use of the International System of Units (SI), pro‐

vide the legal interpretation of and guidelines for the use of the SI in the

United States, as described in the Interpretation of the International System

of Units (SI) for the United States. These publications provide standardized

guidance on how measurement units and results should be presented in

writing.

Black Dots

One of the authors is often quoted as saying “if we [measurement scientists]

don’t get communication of measurement results right, who will?” Regular

review of measurement results and measurement uncertainties on calibra‐

tion certificates and in laboratory documents yield numerous errors that

can negatively impact the interpretation of the results by a user. Examples

3 In the Bible, a city (now thought to be Babylon) in Shinar where God confounded

a presumptuous attempt to build a tower into heaven by confusing the language

of its builders into many mutually incomprehensible languages. (http://www.the‐

freedictionary.com/Babel+effect, 2015‐01‐12.)

4 SI Brochure: The International System of Units (SI) [8th edition, 2006; updated in

2014], available for free: http://www.bipm.org/en/publications/si‐brochure/, 2015‐

01‐12. 

5 The International System of Units (SI), NIST SP 330, Edition: 2008. Guide for the

Use of International System of Units (SI), NIST SP 811, Edition: 2008. Available for

free: http://www.nist.gov/pml/wmd/metric/metric‐pubs.cfm, 2015‐01‐12.
W&M Connection 4 Volume 7 Issue 4

January 26 (2 hr)

Webinar ‐ Software Verification and Validation

2:00 p.m. ‐ 4:00 p.m.

Class No. 5445

January 30 ‐ February 3 (5 days)

Fundamentals of Metrology (SIM ONLY)*

Class No. 5449

NIST/Gaithersburg, MD

February 6 ‐ 10 (5 days)

Fundamentals of Metrology

Class No. 5433

NIST/Gaithersburg, MD

February 13 ‐ 17 (5 days)

Fundamentals of Metrology

Class No. 5434

NIST/Gaithersburg, MD

February 16 (2 hr)

Webinar ‐ Conducting an Effective Management Re‐

view

2:00 p.m. ‐ 4:00 p.m.

Class No. 5416

February 23 (2 hr)

Webinar ‐ Basic Uncertainty Concepts

2:00 p.m. ‐ 4:00 p.m.

Class No. 5446

February 27 ‐ March 3 (5 days)

Fundamentos de Metrologia

Class No. 5447

NIST/Gaithersburg, MD

March 2 (2 hr)

Webinar ‐ Internal Auditing Best Practices

2:00 p.m. ‐ 4:00 p.m.

Class No. 5420

March 13 ‐ 24 (10 days)

Mass Metrology Seminar

Class No. 5435

NIST/Gaithersburg, MD

May 15 ‐ 26 (10 days)

Mass Metrology Seminar

Class No. 5436

NIST/Gaithersburg, MD

June 5 ‐ 16 (9 days)

Advanced Mass Seminar (Rev. 2015)

Class No. 5437

NIST/Gaithersburg, MD

June 19 ‐ 30 (10 days)

Metrologia de Masas Seminar

Class No. 5448

NIST/Gaithersburg, MD

August 17 (2 hr)

Webinar ‐ Contract Review

2:00 ‐ 4:00 p.m.

Class No. 5421

*State W&M labs only or invitation only.

**Regional Measurement Assurance Program

“MEMBERS” (State and Industry RMAP mem‐

ber laboratories.)

are often observed where measurement uncertainties are not included, are

incomplete, or are inaccurate, incorrect terminology is used, typographical

errors are left uncorrected, results are presented without appropriate sig‐

nificant digits, unit conversions are made inaccurately, and incorrect units

and symbols are presented or correct units are inconsistently used. The au‐

thors refer to these errors in communications as black dots. That is, a black

dot on a clear page is what is noticed and is obvious by the reader or cus‐

tomer. These types of blemishes will be what are remembered, despite the

presence of other accurate information that’s presented. Errors in reporting

results can lead to confusion or bad decisions by the user, often with critical

impacts. Black dots destroy credibility of the provider of the measurement

results. 

Examples of common black dots, as ripped from the headlines or as readily

observed in daily life, include6

: 

• Failure to include leading zeroes when presenting measurement re‐

sults so that a child is given a 5 mL dosage instead of a 0.5 mL

dosage leading to death;

• Failure to effectively communicate requirements and convert meas‐

urement units when using two measurement systems lead to the

loss of the NASA Mars Climate Orbiter; 

• The 2003 Disneyland Tokyo Space Mountain roller coaster accident

highlights a scenario where axle and bearing design specifications

were converted to metric units and implemented in an amusement

ride. After the design change took place, time passed and routine

maintenance called for the replaced bearings. However, instead of

being replaced with the updated design (metric) bearings, they

were replaced with the incorrect size based on the original (non‐

metric) design. Use of the wrong size bearing created a gap be‐

tween the axle and bearing. Over time, extra vibration and stress

cause the axle to fail and the roller coaster to derail. Luckily, no pas‐

sengers were injured during the ride!7

• Recently, a measurement calculation mistake was discovered in a

laminate wood flooring study conducted by the U.S. Centers for Dis‐

ease Control and Prevention (CDC). The federal agency issued a

correction notice to a report about the quantity of formaldehyde

in the product revealing that, as result of not converting from feet

to meters, an incorrect value for ceiling height caused CDC scientists

to significantly underestimate the health risks in the original study

report.8, 9

• The NIST Office of Weights and Measures (OWM) conducted a la‐

beling assessment of over 1100 packages, including products food,

home and personal care products, hobby and arts and crafts prod‐

6 U.S. Metric Association, Unit Mixups (2016‐02‐26) http://www.us‐metric.org/unit‐

mixups/ 

7 U.C. Davis, ChemWiki, Case Studies: Metric/English Conversion Errors (2016‐02‐

26) http://chemwiki.ucdavis.edu/Core/Analytical_Chemistry/Quantifying_Na‐

ture/Case_Studies%3A_Metric%2F%2FEnglish_Conversion_Errors#Disneyland_To

kyo:_A_Bumpy_Blunder

8 CDC Fixes Major Error in Flooring Risk Report: Not Converting to Metric, Retraction

Watch (2016‐02‐24) http://retractionwatch.com/2016/02/22/cdc‐fixes‐major‐error‐

in‐flooring‐risk‐report‐not‐converting‐to‐metric/

9 CDC Revises Health Risk Assessment Of Flooring After Math Error, Vocativ (2016‐

02‐24) http://www.vocativ.com/news/289002/cdc‐laminate‐cancer/
W&M Connection 5 Volume 7 Issue 4

ucts, automotive, hardware, office products, and pet supplies and observed that some inappropriate unit symbols

were in use within the net quantity of contents statements.10 OWM offers packaging and labeling training oppor‐

tunities to help packers and retailers become more familiar with state and federal labeling requirements. 

Document control is also important within both laboratory and a wide variety of operational environments. Version control

and archiving records are essential tools to ensure changes made over time are effectively communicated to all personnel

impacted by a change. Failure to maintain adequate control of laboratory documents, for example calibration certificate

templates, can be the root cause for black dots that are released to customers. 

One goal of ensuring quality when communicating accurate measurement results should always be to avoid black dots!

Quality communications of measurement results require a rigorous review of all communications for use of accurate ter‐

minology, completeness, and use of appropriate measurement units and symbols in addition to editorial reviews for typo‐

graphical and grammatical errors. The use of the publications noted in this article will guide the user to standardized

resources for improving the quality, accuracy, and communication of measurement results. 

Avoid the Black Dot: Know Where to Get the Answers

Knowing where to find the answers to common technical ques‐

tions can be invaluable. Many questions arise when writing lab‐

oratory documents, clarifying measurement results, and

implementing measurement system best practices. The proper

use of measurement units and symbols in laboratory documents,

such as calibration reports, control charts, uncertainty tables, and

standard operating procedures (SOP) is critical to effectively com‐

municating technical information both internally between labo‐

ratory personnel and externally with customers.

Congress has assigned the responsibility to interpret or modify

the SI (International System of Units) for use in the United States

to the Secretary of Commerce. This responsibility has been dele‐

gated by the Secretary to NIST. To accomplish this mission, NIST

provides a number of SI resources and information to support science, technology, trade, and commerce. 

NIST Special Publication (SP) 811, Guide for the Use of the International System of Units (SI), provides detailed rules for SI

writing style, including a useful Editorial Checklist at the beginning of the document.11

Together NIST Special Publication (SP) 330, The International System of Units (SI), and SP 811 provide the legal interpretation

of and guidelines for the use of the SI in the United States. NIST also serves as the U.S. technical representative to the In‐

ternational Bureau of Weights and Measures (BIPM) that defines the SI. These publications are used to guide the meas‐

urement unit style in technical and documentary standards.

SP 811 is written for technical professional audiences, including engineers, scientists, and academics. Appendix B provides

rounding guidance as well as Unit Conversion Factors for a broad set of measurement units. NIST has produced several

other similar technical guides for a diverse group of audiences, including LC 1137, Metric Style Guide for the News Media,

which provides condensed SI content to highlight commonly used measurement information.12 A convenient hub of SI

style guidance is available on the NIST Metric Program’s “Writing with Metric Units” website.13

Use a Leading Zero. It’s appropriate to use what’s known as a leading zero before the decimal marker to ensure the quantity

is appropriately interpreted and avoid the consequences of a misplaced decimal point. For numbers less than one, a zero

is written before the decimal marker.14 Without a leading zero, a value like .25 might be visually misinterpreted as 25, an

10 NIST OWM Marketplace Assessment ‐ Metric Labeling on Packages in Retail Stores (December 2009) 

http://www.nist.gov/pml/wmd/metric/upload/Marketplace‐Assessment‐Metric‐Labeling‐Retail‐Stores‐Dec2009.pdf

11 NIST SP 811, Guide for the Use of the International System of Units (SI), (2016‐02‐24),

http://www.nist.gov/customcf/get_pdf.cfm?pub_id=200349 

12 NIST LC 1137, Metric Style Guide for the News Media (2016‐02‐26) http://www.nist.gov/pml/wmd/metric/upload/LC‐1137‐Metric‐

Style‐Guide‐News‐Media‐1997.pdf

13 NIST Metric Program, Writing with Metric Units (2016‐02‐24) http://www.nist.gov/pml/wmd/metric/writing‐metric.cfm

14 NIST SP 811, Guide for the Use of the International System of Units (SI), Section 10.5.2 (2016‐02‐24),

http://www.nist.gov/pml/pubs/sp811/indexfull.cfm

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Barry N. Taylor and Ambler Thomps

NIST Special Publication 330 2008

son, Editors

8 Edition

Figure 1. NIST SP811 and SP330 ‐ Key Technical SI Resources
W&M Connection 6 Volume 7 Issue 4

error of 100 times greater magnitude. For example, if the quantity represented a pharmaceutical medication dose, it’s

highly likely that harm or a worse health effect would result from the error.

Avoid Unit Conversions Errors. A fundamental benefit of SI use is a reduction

of errors due to measurement conversions between U.S. customary units and

the SI. Eliminating conversions altogether can negate the need to document

which conversion factors are being used and their source. Conversion calcu‐

lations require rigorous software validation, which is an expensive and time

consuming process. At best, the price of conversion calculation errors can

be expensive. At worst, consequences can be a matter of life and death.

The crash of the $125 million NASA Mars Climate Orbital spacecraft in 1999

was a wake‐up call for potential errors related to working with multiple meas‐

urement systems. The mishap occurred when the spacecraft entered the

Mars atmosphere on a trajectory that was too low.15 NASA later determined

that the root cause of the erroneous trajectory and velocity calculations were

due to the contractor failing to use SI units of force (Newton, N), as specified

by NASA, within the coding of a ground software file used in trajectory mod‐

els. One corrective action recommended by NASA was a software audit to

evaluate specification compliance on all data transferred between NASA and

the contractor.16

Several helpful conversion factor resources have been made available on the NIST Metric Program’s “Unit Conversion” web‐

site.17 Caution is recommended to those developing unit conversion software or using an online calculator for technical

purposes. It’s important to conduct a rigorous validation and verification analysis before implementing unit conversion

software.

Spelling and Pronunciation. Spelling and pronunciation of measurement units can also be challenging topics in practice.

One of the advantages of the SI over the many other historic and customary measurement unit systems is that although

unit names and prefixes may be spelled differently in different languages, the SI provides a coherent set of internationally

accepted unit symbols that can be used to communicate across all languages. For example, the names of the units them‐

selves vary in spelling and pronunciation according to national practices.18

In NIST SP 811, the spelling of English words is

made in accordance with the U.S. Government

Printing Office Style Manual, which follows Web‐

ster’s Third New International Dictionary rather

than the Oxford Dictionary. The spellings “meter,”

“liter,” and “deka” are used rather than “metre,”

“litre,” and “deca” as in the original BIPM English

text of the SI Brochure.

The BIPM SI Brochure is the definitive international reference on the SI and is published by the International Bureau of

Weights and Measures (BIPM).19 The text is published in French language (official version), followed by the English language

text. Neither the French or English text provide pronunciation guidance. The SI Brochure content is widely translated into

many other languages, which may also explain why pronunciation isn’t specifically addressed. Interestingly, the International

Vocabulary of Metrology (VIM) doesn’t address pronunciation.20

15 CNN, Metric Mishap Caused Loss of NASA Orbiter (2016‐02‐26) http://www.cnn.com/TECH/space/9909/30/mars.metric.02/

16 National Aeronautics and Space Administration (NASA), Mars Climate Orbiter Mishap Investigation Board Phase I Report, Novem‐

ber 10, 1999.

17 NIST Metric Program, Unit Conversion (2016‐02‐24) http://www.nist.gov/pml/wmd/metric/unit‐conversion.cfm

18 Metric Methods, SI Crosses All Language Barriers (2016‐02‐26) http://metricmethods.com/Multilingual_SI_unit_names.gif

19 Bureau International des Poids et Mesures/ International Bureau of Weights and Measures, SI Brochure (2016‐02‐26),

http://www.bipm.org/en/publications/si‐brochure/

20 VIM3: International Vocabulary of Metrology – Basic and General Concepts and Associated Terms (2016‐02‐26)

http://www.bipm.org/en/publications/guides/vim.html

Figure 2. Artist Rendition of NASA Mars Climate

Orbiter. Image Credit: NASA.

Unit Symbol

Language m s kg

English (U.S.) meter second kilogram

Spanish metro segundo kilogramo

Italian metro secondo chilogrammo 
W&M Connection 7 Volume 7 Issue 4

Capitalization of Units, Symbols, and Prefixes. The names of all units start with a lower case letter except at the beginning

of the sentence or title, for example: pascal, becquerel, newton, tesla. In the example for degree Celsius (symbol °C), the

unit “degree” is lower case but the modifier “Celsius” is capitalized because it is the name of a person. A space is left be‐

tween the numerical value and unit symbol and values are not hyphenated (20 °C and 10 kg are correct; 20°C, 20° C, 10‐

kg or 10kg are not correct). If the unit name is spelled out during use, then normal grammar rules are applied.

Unit symbols are written in lower case letters (e.g., m for meter, s for second, kg for kilogram). However, symbols for units

derived from the name of a person are capitalized (W for watt, V for volt, Pa for pascal, K for kelvin, etc.). The recommended

symbol for the liter in the United States is also capitalized as L to avoid misinterpreting l (lowercase L) with the numeral 1.

The period punctuation mark should not be used following a unit symbol (or abbreviation). For example, gram is repre‐

sented “g” not “g.” (g period). Symbols of prefixes that mean a million or more are capitalized and those less than a million

are lower case. For example, M for mega (millions), m for milli (thousandths). 

U.S. Customary Units. Since the development of the SI, many of the style requirements have been applied to non‐SI meas‐

urement systems, including U.S. Customary units (e.g., inch, feet, yard, mile, ounce, pound, fluid ounce, gill, gallon). Al‐

though NIST does not publish a style resource for U.S. Customary units, NIST Handbook (HB) 44, Specifications, Tolerance,

and Other Technical Requirements for Weighing and Measuring Devices,” Appendix C. General Tables of Units of Measure‐

ment is a good resource for U.S. Customary units used in trade and commerce, their relationships, and unit conversion fac‐

tors.21

Because of the importance of the SI (metric system) as an international standard, its use in product design, manufacturing,

marketing, and labeling is essential for U.S. industry’s success in the global marketplace. The NIST Metric Program encour‐

ages the use of the SI in all facets of education, including honing of worker skills. The successful voluntary transition of the

United States to the SI is a critical factor in the competitive economic success of industry. Questions regarding metric

system (SI) use, style, or related publications can be directed to TheSI@nist.gov. 

Accuracy in the use of terminology, measurement results, and measurement units is critical for avoiding the embarrassment

of having others find black dots in your scientific communications. Numerous resources are available to help you avoid

being responsible for inaccuracies reported on calibration certificate and the next problematic news headline regarding

the inaccurate use of measurement units.

21 NIST Handbook (HB) 44 (Current Edition), Appendix C, General Tables of Units of Measurement (2016‐02‐26)

http://www.nist.gov/pml/wmd/pubs/hb44.cfm

Back to the Vikings!

Carol Hockert retired from the National Institute of Standards and Technology (NIST) on June 3rd

to head back to the home of the Vikings, Ole and Sven jokes, but, more importantly, her family!

Carol started working at the NIST, Office of Weights and Measures (OWM) early in 2006 after

working as the Metrologist and Director for the Minnesota Office Weights and Measures. Carol

led the office to a move back onto the main campus from “NIST North,” through a transition as

the Weights and Measures Division within Technology Services, to again become the Office of

Weights and Measures within the Physical Measurements Laboratory. During her tenure, she fa‐

cilitated the accreditation of NIST, OWM to provide certified training credit hours to participants

in the OWM training courses.

Carol enthusiastically engaged with the National Conference on Weights and Measures (NCWM)

and provided ongoing support for office activities on regional, national, and international levels.

As noted by the NCWM: 

Employee News
W&M Connection 8 Volume 7 Issue 4

“Carol’s legacy includes her dedication to improving and increasing training for state and local weights and meas‐

ures officials. She helped establish a NIST Training Grant, which was awarded to NCWM. The funds from this

grant enable weights and measures officials to attend classes designed to qualify technically expert inspectors

as skilled trainers. The grant is also used to offset travel costs for these new trainers to teach other regulatory of‐

ficials and to augment NIST’s national training program. Courses are offered on inspection of scales, fuel dis‐

pensers, price verification inspections, and evaluating the net content of packaged products. Ms. Hockert also

used the grant to bring officials together for Weights and Measures Administrators Workshops where training

and seminars on management, policy development, and effective enforcement methods were held for both new

and seasoned administrators.”

Carol’s passion for metrology led her to serve in several capacities in the National Conference of Standards Laboratories In‐

ternational (NCSLI), including as President (2008), Conference Technical Program Chair (2012‐present), and NCSLI Repre‐

sentative to the Collège Français de Metrologie (CFM). She has lectured internationally on the U.S. system of weights and

measures (e.g., Japan in 2012, Colombia in 2013), and served as a Member of the Organizing Committee of the 16th Inter‐

national Congress of Metrology (2013). Her tact, graciousness, and enthusiasm have greatly enhanced the presence of the

United States in the international metrology world. As a result of her longstanding support of NCSLI, Carol was awarded

the prestigious NCSLI Wildhack Award. She continues in her retirement as the Technical Program Chair for the annual con‐

ference. 

The week before Carol left NIST, she was presented with a Sigma Xi, Outstanding Service in Support of NIST Scientists Award.

We in OWM also wish to thank Carol for her Outstanding Service to weights and measures and wish her well in an active

working retirement. Carol will continue on contract with OWM on some specific knowledge transfer projects to aid in the

transition of the new OWM Chief early in 2017, some regional training efforts, and activities associated with an NCWM

working group. She will also return to conducting NVLAP assessments and already completed the NVLAP assessor training

since she retired. Apparently, she wasn’t ready to slow down just yet! But, for Carol, being home in Minnesota (even when

it’s cold!) with her Mom, siblings, children, and grandchildren – and of course with her beloved Vikings – are the key things

that were missing while she was living in Maryland. We wish Carol well and look forward to continuing our working rela‐

tionship remotely.

NATIONAL CONFERENCE ON WEIGHTS

AND MEASURES

101TH ANNUAL MEETING

JULY 24 ‐ 28, 2016

DENVER, COLORADO

Registration and lodging information for the July meeting

is available online at:

https://www.ncwm.net/sems/event_detail/2016‐annual‐

co. 

The meeting schedule, and supporting documents are also

available at this website location.

The Office of Weights and Measures

will glady include your weights and measures related events in our 

Training and Events Calendar.

Contact the Editor: Linda.Crown@nist.gov

http://www.nist.gov/pml/wmd/calendar.cfm

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