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PUBLICATIONS A11 103081 380

S"uiripVSNE 1989 C. C.1 N>STand Technology
On the cover: The supersonic inert gas metal atomizer (SIGMA) is used

in an intelligent processing of materials program at NIST. The cooperative program is aimed at automating the

production of rapidly solidified metal powders. From left to right are Frank

Biancaniello, James Ingram of Hoeganaes Corp., and Stephen

Bidder. See article on page 10.
National institute of Standards and Teclinology

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Research Reports

U.S. DEPARTMENT OF COMMERCE

Robert A. Mosbacher, Secretary

National Institute of Standards and Technology Raymond G. Kammer, Acting Director

National Institute of Standards and Technology

Gaithersburg, MD 20899

301/975-2000

Boulder, CO 80303

303/497-3000

June 1989

NIST Special Publication 765

Prepared by the Public Information

Division A903 Administration Building

National Institute of Standards and Technology

Gaithersburg, MD 20899

301/975-2762

Any mention of commercial products

is for information only, it does not imply recommendation or endorsement

by the National Institute of Standards and Technology nor does it imply that the products mentioned are necessarily

the best available for the purpose.

The National Bureau of Standards became

the National Institute of Standards and

Technology on August 23, 1988, under the Omnibus Trade and Competitiveness Act. NIST retains all NBS functions. Its new

programs will encourage improved use of technology by U.S. industry.

Research Update

Computer Security: Protection Is the Name of the Game 5

'Standard Crack' Helps Detect Metal Fatigue in Aircraft 9

Building Quality into Advanced Materials during Processing 10

'HIPing': From Metal Powders to Reliable Materials 12

Exploring Earth's Formation 14

NIST: Helping Industry To Compete 16

Tracking Time 20

Movies Reveal Secrets of Materials 24

Technique Sterilizes Clinical Instruments in Seconds 26

Can Smoke Control Systems Save Lives and Property? 28

New Publications 30

Conference Calendar 32
Research Update

Industry To Study Bioseparations

at NIST

Cell Technology Inc., of Boulder, Colo.,

has established a Research Associate

Program at NIST's Boulder laboratories

to study bioproduct separation utilizing aqueous two-phase extraction and elec- trophoresis. The University of Colorado

(CU) and the Colorado Advanced Technology Institute are also participants in the program. Cell Technology has a

product, Imuvert, derived from the Gramnegative bacterium Serratia marcescens, which has shown encouraging results in regressing tumors. The company currently uses ultracentrifuges to separate

components of the bacterium but this pro- duces only small amounts of ribosomes

and vesicles, the desired product. A CU

graduate research assistant will work at NIST to determine whether or not vesicles and ribosomes can be separated in larger quantities from other cellular debris using aqueous two-phase extraction

or electrophoresis. The NIST Research

Associate Program provides an opportunity for scientists and engineers from

companies and other organizations to work with NIST researchers on programs

of mutual interest.

Final Rule Issued on Toy Firearms

The Technology Administration of the

U.S. Commerce Department issued a

final rule, effective May 5, 1989, which

prohibits the manufacturing, entering into commerce, shipping, transporting, or re- ceipt of any toy, imitation, or look-alike firearm unless it contains or has affixed

to it a marking approved by the Secretary of Commerce. The final rule specifies the markings established under

Section 4 of the Federal Energy Management Improvement Act of 1988. The law does not apply to traditional BB, paint

ball, or pellet-firing air guns that expel a

projectile through the force of compressed air, compressed gas, mechanical firing action, or any combination. The

rule also waives marking requirements

for any toy, look-alike, or imitation firearm

that will be used only in the theatrical, movie, or television industries. For further

details, contact: Stanley I. Warshaw,

NIST, A603 Administration BIdg.,

Gaithersburg, MD 20899, 301/975-4000.

Materials Aimed at Improving

Pesticide, PCB Analyses

Scientists seeking to develop or validate the accuracy of analytical methods for measuring selected pesticides, polychlorinated biphenyls (PCB's), and alphatocopherol (a form of vitamin E) in fish and other fatty food products should find a new Standard Reference Material (SRM) useful. The SRM contains certified concentrations of six chlorinated pesticides (hexachlorobenzene, alpha-HCH,

trans-chlordane, cis-chlordane, trans- nonachlor, and dieldrin), five individual PCB's, and the nutrient alpha-tocopherol

in cod liver oil. In addition to containing

the certified components, the SRM also has noncertified concentrations of six dioxin compounds and a related compound, octachlorodibenzofuran. The new

material, SRM 1588, Organics in Cod

Liver Oil, is available for $199 per set of

five sealed vials from the Office of Standard Reference Materials, NIST, B31

Chemistry BIdg., Gaithersburg, MD

20899, 301/975-6776.

Gas Kinetics Database Available

A new computerized database with an

extensive compilation of information on

the rates of chemical reactions important

to research chemists, environmental

scientists, and combustion engineers

has been developed by NIST scientists. Available on a floppy disk for personal

computers (PC's), it contains data on the

rates of approximately 2,000 chemical re- actions with more than 5,300 individual data entries. The database is an important tool for modeling combustion sys- tems or chemical processes occurring in the atmosphere. This type of data is nec- essary in understanding the reactions of chemicals and their role in depleting the

Earth's ozone layer. A special software

option allows users to display rapidly in a

single graphic all of the rate constants determined for a single chemical reaction as a function of temperature. These

plots showing all of the available information are useful for revealing discrepancies in experimental results. NIST Standard Reference Database 17, Gas

Kinetics, is available for $190 from the

Office of Standard Reference Data, NIST,

A320 Physics BIdg., Gaithersburg, MD

20899, 301/975-2208.

200 Labs Accredited for Asbestos

More than 200 labs received the first accreditations to perform analyses for asbestos content in bulk insulation and

building materials under the new

National Voluntary Laboratory Accreditation Program (NVLAP) for bulk asbestos

in schools. The labs have demonstrated

their competence to analyze bulk material samples by polarized light microscopy using test method procedures

specified by the Environmental Protection Agency. Approximately 500 other labs are being evaluated to determine

their ability to meet NVLAP requirements.

The accredited labs have undergone an

on-site assessment performed by a technical expert in optical microscopy and

have demonstrated full compliance with NIST technical evaluation criteria. The

2
labs also have successfully participated

in the first round of proficiency testing in which they were required to determine

the presence and type of asbestos in pre- characterized quality assurance materials developed by NIST. For information on NVLAP, contact; National Voluntary

Laboratory Accreditation Program, NIST,

BIdg. 41 1 , Gaithersburg, MD 20899,

301/975-4016.

World's Smallest Prism Made

trations of these gases is important to the properties of steel because they contribute markedly to steel brittleness and

therefore to the strength and durability of steels. Standard Reference Material (SRM) 1754, Oxygen and Nitrogen in Low-Alloy Steel, AISl 4320, is in rod form, 0.95 cm X 0.95 cm x 10.2 cm. It was

certified through the NIST/ASTM Re- search Associate Program involving nine

industrial laboratories. SRM 1754 is avail- able for $119 per unit of 1 rod from the

Office of Standard Reference Materials,

NIST, B31 1 Chemistry BIdg., Gaithersburg, MD 20899, 301/975-6776.

NIST Studying Burning

of Crude Oil Spills

Can an oil spill be cleaned up by burning? What happens when oil on water burns? How much smoke is produced?

What are the physical and chemical properties of the smoke? These are some of the questions NIST researchers are at- tempting to answer in a project to eval- uate combustion of oil spills on water. In a recent paper, the researchers dis- cussed the results of their preliminary

laboratory tests on three different crude

oils. One of the primary thrusts of the re- search is to measure the amount of selected chemical components in the smoke from a crude oil fire. The re- searchers measured the quantity of several polynuclear aromatic (PAH) compounds in both the original crude oil and

the smoke. (PAH compounds in crude oil are of environmental concern because some have been reported to cause

cancer in animals.) The NIST researchers

found that the amount of PAH compounds in the smoke nearly equaled that

in the original oil burned. The researchers also have developed a preliminary

computer model that can help predict

how smoke from a burning oil spill will be

dispersed. The work is being done in col- laboration with the U.S. Department of the Interior and Environment Canada.

'ZIP' Will Find Most Economic

Levels of Insulation

How much insulation should be installed

in a house? A new computer program

called ZIP can help find the answer. Quick and easy to use, ZIP can provide

customized estimates of the most economic levels of thermal insulation for building components such as attics, walls, floors, crawlspaces, and basements. ZIP determines these estimates

by searching internal data files containing local weather information and energy

and insulation costs all keyed to the

user's postal ZIP code. The program and

supporting files are contained on a single

diskette and will run on MS-DOS systems

with 256K of RAM. ZIP was designed by

NIST in conjunction with the Department

of Energy's Oak Ridge National Laboratory. The disk is available from several sources including MTS Software, 3534

Knollstone, St. Louis, MO 63135,

314/524-2202 for $5 and PC-SIG, 1030D

East Duane Ave., Sunnyvale, CA 94086,

408/730-9291 for $6. It also is available from the National Technical Information

Service, Springfield, VA 22161; call 703/487-4600 for ordering information.

Material Can Help Pinpoint

Nicotine Exposure

Researchers studying human exposure

to cigarette smoke—both active and passive exposure—need to ensure that the methods they use to track the concentration of nicotine by-products in urine

Researchers at the NIST laboratories in Boulder, Colo., have created what they

believe to be the smallest optical prism ever made. The microscopic glass prism

is only 0.005 inch on a side—about the thickness of a heavy sheet of paper.

Barely visible to the naked eye, the "mi- croprism" may be used in microoptics

and fiber optics research and instrumentation—for example, as a test probe for making accurate measurements of the performance characteristics of optical

fibers in the tight confines of an inte- grated optical circuit. Besides being

measuring tools, microprisms might also eventually have applications as actual elements in miniaturized optical circuits. Zongjian Sun, a guest scientist at NIST

from Tongji University of Shanghai,

People's Republic of China, developed

the procedure to grind the infinitesimal prism in conjunction with Robert Gallawa, a physicist in NIST's Electromagnetic

Technology Division.

New Low-Alloy Steel Calibration

Standard Available

A new standard for checking and cali- brating oxygen and nitrogen analyzers in the steel industry has been developed

under a cooperative program between

ASTM and NIST. Information on concen3
samples are reliable. A new bottled refer- ence material (RM), issued jointly by

NIST and the Environmental Protection Agency, can assist laboratories in validat- ing urine measurement methods. It is designed for determining levels of cotinine,

which is the major urinary metabolite of nicotine. With the new material, laboratory personnel can test the reliability of in- struments and methods by analyzing the RM the same way as a urine sample and

comparing results with the ones listed for the RM. The new material is sold in a kit that includes vials of freeze-dried urine,

each containing cotinine at one of three

levels: blank, low, and high. These quantities are typical of, respectively, non- smokers with no exposure to cigarette

smoke, nonsmokers with passive exposure to smoke, and smokers. RM 8444

costs $148 and is available from the Office of Standard Reference Materials,

NIST, B311 Chemistry BIdg., Gaithersburg, MD 20899, 301/975-6776.

Measuring High-Temperature

Superconductors

NIST researchers have developed a

novel apparatus for variable-temperature

measurements of high-temperature

superconductors. Termed a cryogenic

bathysphere, it can rapidly (in 10

minutes) test superconductors over a range of temperatures from 300 to 4 K, or it can be used to stabilize the temperature at a given value. The tiny

(3-centimeter width) device has no moving parts and can be used in compact spaces such as shipping Dewars

and small-bore high-field magnets. The

apparatus has been tested successfully

in liquid helium and liquid nitrogen by

measuring the resistance-versustemperature curves of several superconductors. A paper describing a prototype

device is available from Jo Emery, NIST,

Division 104, Boulder, CO 80303.

NIST Invites Vendors

for GOSIP Evaluation Project

The National Computer Systems Laboratory at NIST is developing guidelines to help users evaluate different implementations of GOSIP (Government Open Systems Interconnection Profile) applications. To help expedite the project,

vendors are invited to lend to NIST soft- ware and hardware that implement

message handling systems and file transfer, access, and management applications. Currently, GOSIP supports both applications. GOSIP was approved last fall as a Federal Information Processing

Standard (PIPS), developed by NIST for use by the federal government. The

standard defines a common set of data

communication protocols that enables

computer systems developed by differ- ent vendors to communicate and en- ables the users of different applications on these systems to exchange information. For information on the evaluation

project, contact Steve Trus, NIST, B225

Technology BIdg., Gaithersburg, MD

20899,301/975-3617.

N.Y. Firm Joins with NIST To

Investigate Sensors

CID Technologies Inc. (CIDTEC), of Liver- pool, N.Y., has begun a program with NIST that will investigate the effects of various forms of nuclear irradiation on charge injection device (CID) sensors and cameras. CID sensors are sophisticated imaging devices that offer numer- ous technical advantages over related techniques. For example, CID cameras

allow excellent exposure control in lowlight situations, but they also are more

tolerant to intense light and produce

accurate image detail even under ex- treme lighting conditions. This makes the devices ideal for purposes such as missile tracking, semiconductor pattern recognition, and factory inspection. For this cooperative project, CIDTEC and NIST re- searchers will use the NIST 20-megawatt

reactor to expose sensors and associated CID components to x-ray, gamma,

beta, neutron, and charged particle en- vironments to determine "radiation hard- ness" of the materials. They will gauge

the electronic characteristics of the devices before, during, and after radiation exposure. They also will explore the chemistry uses of CID's by developing

spectroscopy applications to improve

chemical analysis accuracy and detection limits.

Tiltmeter Studies in Colorado

and Wyoming

Scientists at the NIST-University of Colorado Joint Institute for Laboratory

Astrophysics (JILA) have completed field studies of specially designed tiltmeters in Erie, Colo., and Yellowstone National

Park, Wyo. Tiltmeters are highly sensitive devices which are sunk deep into the

Earth and which are designed to measure the slightest tilt in the Earth's surface. They might be used, among

other things, as early-warning predictors

for earthquakes. The JILA scientists found good agreement between their measurements and measurements of Earth tides on the Colorado plains but wide disagreements between these

measurements in Yellowstone Park

where the instruments were placed

above a collapsed caldera. Only near a

fault zone in Germany have comparably

large tilt anomalies been observed, they

report. For copies of two papers explaining their work, contact Jo Emery, NIST,

Division 104, Boulder, CO 80303.

4
Computer Security:

Protection is the

Name of tlie Game

r. Stuart Katzke has been talking a lot lately about viruses,

bugs, and infections. But Katzke is not a nnedical doctor, and

no human can catch these ailments. Katzke manages a team

of computer scientists, mathematicians, and engineers at the

National Institute of Standards and Technology. Their job is to

find ways to help protect the federal government's unclassified computer

systems against problems

including malicious software pro- grams called viruses.

But, while computer viruses are nothing to sneeze at, Katzke

and other experts agree there are more pressing computer security

problems. Computerized information, says Katzke, must be pro- tected from not only intentional acts such as sabotage or theft, but also natural disasters, hard- ware and equipment failure, and

operator error. Computer Security Act

Since the early 1970's, NIST has

been developing cost-effective ways to help organizations—both

in government and private in- dustry—protect computerized

data. These methods include

sound management practices as

well as technical solutions. With the passage of the Computer Security Act of 1987 (P.L. 100-235) that role was broadened to give NIST the primary responsibility for protecting the

security and privacy of unclassified information in federal computer systems. "We want ... to be the government's leader in

1 finding solutions to the problems

related to the protection of unclassified information," said Ray

Kammer, NIST acting director,

last March before two congressional subcommittees. "I hope that, in the 1990's, we can

say that the federal government

leads the nation in developing

and using cost-effective security

controls," Kammer added.

To help NIST carry out its new

role under the act, the Institute formed a 12-member board. Made up of industry and govern- ment experts, the board is to advise NIST and the Secretary

of Commerce on security and

privacy issues pertaining to unclassified federal computer

systems.

What Is Computer Security?

According to Katzke, computer

security means that data in a computer system are correct and confidential and that the system is available when needed. But, more than that . . . "computer

Before logging onto a networi(, Miles Smid uses a credit card-sized board, called a "smart" token, to perform a

series of authentication checks for security.

5
security means never having to say you're sorry," says Katzke. He adds, "It means your organization from the top dow/n is serious

about computer security and the managers have evaluated what

needs to be protected and have

implemented cost-effective measures to protect it. It means that if something does happen, you're

protected, or at the very least, you know what needs to be done

to recover from the damage."

According to Doug Hunt,

manager of computer security

planning and assistance, an im- portant step toward protecting

data is for an organization to form a comprehensive computer security plan. Although this may seem

obvious, Hunt says it is often over- looked. Such a plan should help

make computer security an inte- gral part of managing an organization's computerized information and keep everyone more aware

of problems and solutions.

In fact, the recently passed

computer security act mandates

that federal agencies develop

plans for systems containing sensitive but unclassified information and submit them to NIST for re- view. Since January, teams of computer security specialists

from NIST and the National Security Agency (NSA) have been re- viewing more than 1,500 plans. "We're not grading or judging the plans as good or bad. Our pur- pose is to provide constructive

comments," says Hunt. He and the teams have found

wide disparities both among and

within agencies in the quality and

completeness of the plans. They

also found that most agencies

need to improve computer security training for all levels of staff. After reviewing the first round of plans this summer. Hunt's group

will begin developing guidelines on both planning for computer

security and training.

Weighing Cost vs. Risk

An important part of developing

a computer security plan is to weigh the costs of controls against the risk of loss. " 'Absolute' security is achieved only at unlimited cost," says Dennis

Steinauer, manager of the computer security management and

evaluation group. "Since most or- ganizations, including federal agencies, do not have unlimited funds, it's important to balance

cost and risk. Controls that are more expensive than the value of the information they protect are

not cost effective," he says. To help achieve this balance,

NIST is investigating techniques

that can be used to identify risks and select cost-effective computer security measures. In col- laboration with NSA, NIST has es- tablished a research laboratory to study methods that are currently available for assessing risk, to develop "standard scenarios"

that can be used in comparing

alternative methods, and to develop guidelines on selecting

risk management procedures.

Locks and Keys

While good management practices and training are essential to protect computers and the data

they handle, computer tech- nology also can be part of the solution. In addition to developing

standards and guidelines for man- agement measures, NIST also works on the technical tools needed for an overall computer

security program. One of the best ways to en- sure that someone cannot read

or alter a data transmission is through cryptography. Cryptography is a mathematical process

that encrypts—or scrambles—the

information so only those with a

secret "key" can unscramble it. Cryptography also can be used

to generate codes that indicate whether unauthorized changes

have been made to a message

while it is in transit in a network or while it is stored in a computer.

In 1977, NIST issued the Data

Encryption Standard (DES) that specifies an encryption algorithm.

Although the DES was developed

for use by the federal government, it is widely used by U.S. in- dustry. For example, it has been

adopted by the American

National Standards Institute and

the American Bankers Association for protecting transfers of funds and securities over communications lines. The Department of the Treasury also is using

it to help protect the billions of dollars in federal funds that are trans- ferred electronically each year. The DES is reviewed by NIST

and the Department of Commerce every 5 years to determine

its adequacy to protect computerized data. After the most recent review in 1987, NIST approved its use for another 5 years, saying it continues to be a sound method

for protecting computerized data. To further encourage use of the DES, NIST validates commer6
cial devices to assure that products properly implement the standard and are compatible with other equipment using the DES.

"This benefits both buyers and

sellers of data encryption devices," says Miles Smid, manager

of the NIST security technology

group. So far 33 products have

been validated. NIST also has

developed standards for managing the keys needed to use the DES algorithm.

Other technology can help

control access to computer net- works. While passwords often are used to authenticate the identity of those wanting access to a net- work, many times they are not used properly, providing little or no protection.

In 1985 NIST issued a stand- ard with basic guidelines for designing and putting into place a password system. Now the Institute is working with the Defense

Advanced Research Projects

Agency and a Minneapolis company, Datakey, Inc., to develop a

prototype system using a "smart" token that will make it tougher for hackers to gain access to a computer network. Essentially a microcomputer on a credit card-sized

board, the token performs a series of authentication checks

before allowing a user to log on to a network. The researchers are considering incorporating a physical characteristic of the user, such as fingerprints, into a future version of the system.

"It's similar to protecting your

house," says Smid. "When you go

out for the evening, you usually

lock your door. If you lock your door and turn on your porch light.

For Your information

NIST researchers have produced a number of publications

dealing with computer security. Following is a partial list of the

publications that are available from the Government Printing Office (GPO) or the National Technical Information Service (NTIS).

See bottom of page 31 for ordering information.

Smart Card Technology: New Methods for Computer

Access Control, Martha E. Haykin and Robert B.J. Warnar, NBS

Spec. Pub. 500-157 (September 1988). Order from GPO as stock

no. 003-003-02887-8, $2.75 prepaid. Describes the basic components of a smart card and provides background information on

the underlying integrated circuit technologies. The capabilities of a smart card are discussed, especially its applicability for computer security. The report describes research being conducted

on smart card access control techniques; other major U.S. and in- ternational groups involved in the development of standards for smart cards and related devices are outlined in the appendix. Data Encryption Standard, FIPS PUB 46-1 (January 1988,

Reaffirmed until 1992), Order from NTIS as FIPS PUB 46-1,

$9.95 prepaid. Specifies an algorithm to be implemented in electronics hardware devices and used for the cryptographic protection of sensitive, but unclassified, computer data. The algorithm

uniquely defines the mathematical steps required to transform computer data into a cryptographic cipher and the steps re- quired to transform the cipher back to its original form. This stand- ard has been adopted as a voluntary industry standard. Guide to Auditing for Controls and Security: A System

Development Life Cycle Approach, Zella G. Ruthberg et al., NBS^

Spec. Pub. 500-153 (April 1988). Order from GPO as stock no, 003-003-02856-8, $13.00 prepaid. Describes a process for

auditing the system development life cycle of an automated infor-^ mation system to ensure that controls and security are designed

and built into the system. The guide was developed by the Elec-|

tronic Data Processing Systems Review and Security Work

Group of the Computer Security Project within the President's Council on Integrity and Efficiency and contains bibliographies

and a description of pertinent laws and regulations.

For more information on the NIST computer security program

or to get a complete list of NIST computer security publications,

write or call the Computer Security Division, NIST, A216 Tech-

.nology Bldg., Gaithersburg, MD 20899, 301/975-2934.

7
NIST computer scientists are worldng with researchers from private industry to develop security features for "open" computer networks.

you've made it a little tougher for an intruder. If you lock your door,

turn on your porch light, and acti- vate an alarm, you've made it even tougher. With each layer of security, you've decreased the odds that someone is going to get into your house—or your computer system."

Security for 'Open' Networks

Computer networks bring with them many advantages, such as

quick access to lots of information. But, they also have opened

up new opportunities for mischief

and crime, so graphically demonstrated by a recent virus incident

that wreaked havoc on a nation- wide network of research computers. In addition to developing

tools designed to make data

transmissions safer and to restrict access to networks, NIST is helping to make networks secure as

well as "open."

Since 1983, NIST has been

working with manufacturers,

users, and other government

agencies to develop standards

for "open" systems that will make

it possible for different manufacturers' equipment to communicate. This research will make it easier not only for computers to

talk to each other, but also for net- works to talk to networks. But,

until recently, little attention has

been paid to incorporating security features into these standards.

In a project to do just that, NIST is working with NSA and

several private companies, includ- ing IBM, Hughes Aircraft Corp.,

and Digital Equipment Corp., to develop and test specifications

for security features that can be

built into new networking products. "We are drawing upon technology being developed for the

classified world and modifying it

to use in the unclassified," says Rob Rosenthal, manager of the

protocol security group at NIST. Getting the Bugs Out

While incidents of virus infections

in networks are relatively few,

they have been increasing.

Katzke and his staff are working

with other experts in government

and industry to develop ways to deal with these threats. As a first step, NIST is forming a response

and information center. The center will act as the hub of a net- work of similar centers set up to respond quickly to attacks and as

a resource center where people

could get information and guid- ance on security problems at any

time. During an emergency, such

as a widespread virus attack,

NIST would act as a focal point to coordinate other centers and collect and disseminate information.

'Our Big Story Tonight Is. . . .'

While NIST can provide guidance

and some of the tools needed to protect computerized data, in the end, says Katzke, computer security is largely a matter of attitude. "Many people think about computer security only when they

hear a story about a virus attack

or break-in on the evening news," says Katzke. "But if your organization relies on computers to get its job done, and you are ignoring

computer security, you do so at a

risk. And tonight's news may be

about a break-in to your computer system."

by Jan Kosko

NIST Public Affairs Specialist

8
'Standard Crack'

Helps Detect Metal

Fatigue in Aircraft

A

"standard crack" recently developed at the National Institute of

Standards and Technology can help the airline industry do a

better job of testing for metal fatigue in aircraft. The importance

of testing aircraft for metal fatigue has been underscored by re- cent events, such as the Aloha Airlines fuselage that partially

ripped open in flight last year. Eddy current testing is the method most

often used to detect the cracks,

nornnally invisible to the naked

eye, that lead to this kind of

failure. This type of testing uses

an energized coil of wire to in- duce electrical currents in metals. These currents, which are af- fected by fatigue cracks, are monitored, and an interpretation

is made as to the absence or presence of a defect and its extent. A difficulty of the eddy current technique is the lack of samples

of well-defined "flaws" that accurately simulate fatigue cracks. These are necessary to calibrate accurately eddy current instru- ments and to provide base data

for interpreting test results. Now engineers at the NIST

Boulder, Colo., laboratories have

invented a technique for producing artificial flaws of known sizes which can be used to calibrate

test equipment.

The NIST Office of Standard

Reference Materials in Gaithers- burg, Md., will sell 3-inch by

2-inch blocks of metal containing

these standard defects. The initial offerings will be research prototypes which should be available

this summer.

"There is the potential for enormously wide application of these blocks," says Frederick R.

Fickett, leader of the research

group that designed the "stand- ard crack." Virtually every seg- ment of the transportation in- dustry is concerned about fatigue

cracking of metal; nuclear reactor operators also are interested. Thomas E. Capobianco, a NIST engineer, developed the technique. In simplest terms, Capobianco softens a 3/4-inch- thick piece of metal (in this case aluminum alloy 7075-T6) by heating it, notches it to a known

length and depth with an in- denting tool, and compresses the

metal in the direction perpendicular to the notch until the notch

"disappears" at the surface. " The

beauty of this technique," says Capobianco, "is that by using an

indenting tool to make the notch, we can make the geometry of the cracks anything we want. We can make them look like fatigue

cracks of any configuration and

still know their dimensions."

Capobianco will oversee pro- duction of the research materials and ensure their quality control. "We may not manufacture them

entirely ourselves but we will measure their properties and cus- tomers will be getting a carefully

characterized product," he says. Purchase inquiries should be

made to the Office of Standard

Reference Materials, NIST, B31

1

Chemistry Building, Gaithersburg,

MD 20899, or call 301/975-2012.

by Fred McGehan

NIST Public Affairs Specialist

9
Building Quaiity into

Advanced IVIateriais

during Processing

aterials scientists at the National Institute of Standards

and Technology are seeking researchers in industry, universities, and other organizations who are interested in

participating in collaborative programs on the intelligent

processing of nnaterials (IPM). The IPM concept is a new

computer-based approach for producing advanced polymer, ceramic,

and metal alloy nnaterials that are

far superior to those used today.

The special properties of advanced materials are the results

of microstructures designed and

built into them during processing.

An IPM facility with various on-line nondestructive evaluation (NDE)

sensors and process models can

monitor and control carefully the processing conditions required to give advanced materials many ex- ceptional qualities, such as im- proved strength, unusual magnetic properties, and increased

resistance to heat, friction, wear, and corrosion. Tom Yolken, chief of the NIST

Office of Nondestructive Evaluation, points out that the annual

world market for advanced materials and for the products made

from them is estimated to reach

$300 billion by the year 2000.

There also is a sizeable market

for conventional materials that are

"Our long-range

goal is to develop the

scientific and measurement base that is crucial to U.S. industry's

success. ..."

improved by the use of intelligent

processing technology.

Lyie H. Schwartz, director of the NIST Institute for Materials Science and Engineering, says, "Our long-range goal is to develop the scientific and measure- ment base that is crucial to U.S.

industry's success in capturing a

significant share of the world

market for advanced materials." According to Yolken, advanced materials tend to be

expensive because their production is labor intensive and rejection rates are high. The unpredictable variability of properties

also prevents designers from exploiting the technological advantages of advanced materials. He

points out that the intelligent proc

essing of materials concept will allow for quality to be built into materials during processing

rather than attempting to obtain it by inspection.

Intelligent processing tech- nology involves four principal

interconnected parts: the materials processorvarious apparatuses to press,

cast, or mold materials; a network of on-line NDE sensors to measure or monitor the mi

crostructures of materials during

processing;

control devices, such as

valves, pumps, and motors, that regulate pressure, temperature,

and other processing require- ments; and

a computerized process controller that closes the loop be10
tween the sensors and the process controls. The process controller incor- porates various expert systems,

process models, and data. This computerized "decision-maker" can quickly evaluate information and make rapid adjustments in production processes to achieve

the desired microstructures in advanced materials.

The IPM concept uses

on-line measurements

in real time to control

simultaneously a wide

variety of processing

parameters.

Yolken emphasizes that IPM

technology differs greatly from

conventional automated proc- essing where variables, such

as temperature and pressure, are

automatically controlled to pre- selected values. This does not allow for variations in the incoming materials. The IPM concept

uses on-line measurements in

real time to control simulta- neously a wide variety of proc- essing parameters.

Now there are two IPM pilot demonstrations under development at NIST. An industrial consortium has been established to automate the production of rapidly solidified metal powders

by high-pressure gas atomization. The total IPM package will consist of sensors, process models, and an "expert" computer

system to control the atomization

of liquid metals to produce powders with the desired microstructures for advanced metal alloys.

In another IPM project, NIST

scientists are working with re- searchers from government,

industry, and universities in a

collaborative program on the hot

isostatic pressing (HIPing) of titanium aluminide. The re- searchers are developing sensors, process models, and other measurement tools to automate

the entire production cycle, from raw metal powders to finished parts at near-net, or close-to-final,

shapes. (See article on page 12.)

In addition to the pilot demonstrations, NIST long-range plans

call for collaborative IPM pro- grams in polymers processing,

ceramics processing, and the thermomechanical processing of metals. These programs will address industry needs that were

identified by specialists at a

national workshop on the intelligent processing of materials. Collaborative IPM research opportunities are available where

guest scientists from industry,

government, and universities are able to work at NIST on projects

of mutual interest with salaries paid by their employers. For infor- mation, contact the Office of Nondestructive Evaluation, NIST,

B344 Materials Bldg., Gaithersburg, MD 20899, 301/975-5727.

The NDE office also may be contacted for a copy of Intelligent

Processing of Materials, Report of an Industrial Workshop Conducted by the National Institute of Standards and Technology

(NISTIR 89-4024).

by Roger Rensberger

NIST Public Affairs Specialist

Researchers at NIST prepare for a test run using the supersonic inert gas metal atomizer (SIGMA). Clockwise from bottom left are John Manning, Frank Biancaniello,

Stephen Ridder, and James Ingram, a research

associate from Hoeganaes Corporation.

11
'HIPing': From

Metal Powders to

Reliable Materials

Consolidating rapidly solidified metal powders into close-tofinal, or near-net, shapes through hot isostatic pressing

(HIPing) may turn out to be a very reliable way to make parts

out of advanced alloys, such as titanium aluminide. This highperformance material has great potential for airframe components and engine parts because it is lightweight and performs well at

very high temperatures. But engineers need to overcome a

variety of processing barriers before titanium-aluminide materials with the required internal properties can be produced

cost effectively. Materials scientists at the

National Institute of Standards

and Technology are working with a team of scientists and engi- neers from industn/, universities,

and government to develop the measurement and control tools needed to automate the HIPing

process. The collaborative re- search effort is jointly supported

by NIST and the Defense Advanced Research Projects

Agency (DARPA).

To produce titanium- aluminide alloys using hot isostatic pressing, rapidly solidified metal powders are sealed in a

canister or mold and placed in- side a furnace. The material is then heated to approximately

1100 °C and compressed into solid shapes by hydrostatic pres- sures up to 200 megapascals, or 30,000 pounds per square inch. Robert J. Schaefer, project leader in the NIST metallurgical

processing group, says, "Our

goal is to demonstrate that the re- quired microstructural properties

"The HIPing pro]ect

offers us an opportunity to develop

and test various measurement concepts for

the automated

control of materials

processes.

for titanium-aluminide alloys can

be met by automated HIPing

methods."

Schaefer points out this will re- quire new information for monitoring the overall HIPing process

and measurement data for controlling the densification of metal powders to obtain the correct

microstructures. Concepts for the intelligent

processing of materials (IPM) are being applied to the HIPing project. This is a new computerbased approach for producing

advanced materials that are far superior to those used today.

The special properties of advanced materials, such as exceptional strength and resistance to heat, result from microstructures

designed and built into them

during processing.

The researchers are developing sensors, process models, and

an "expert" computer system to automate the entire production

cycle of titanium-aluminide alloys

and composites, from raw metal powders to finished parts. These

12
measurement tools will ensure the production of reliable materials with the desired properties.

Neville Pugh, chief of the NIST

Metallurgy Division, says, "The

HI Ping project offers us an opportunity to develop and test various

measurement concepts for the automated control of materials processes in the same way

robotics have been tested for dis- crete parts manufacturing."

Pugh says the HIPing of ex- pensive metal alloys also pro- vides a significant savings in materials. With near-net shapes,

producers normally will lose no more than 10 to 20 percent of the

bulk material in the final machining of a part. With conventional

methods, manufacturers typically

utilize only 10 to 30 percent of the

material; the remainder becomes

scrap. NIST eddy current and ultra- sonic sensors to measure the density and microstructures in the metal powders during consolidation will be incorporated in an IPM

computerized control system

being developed for DARPA by

BDM International, inc. The IPM

controller will permit producers to take on-line measurements and

evaluate the information with process models to control the

properties of metal powders

during HIPing.

In a collaborative effort with NIST, University of Cambridge

metallurgist Michael F. Ashby is

. . HIPing Of

expensive metal alloys

also provides a

significant savings

in materials.

developing the process models

that will predict the density of metal powders based on pressure, temperature, and time. NIST

metallurgist Roger B. Clough also

is developing mathematical

models of the mechanical defor- mation process during HIPing.

After the IPM controller sys- tem has been completed, plans

call for various components to be

installed in an industrial setting

for tests under NIST supervision.

NIST also has established an

advisory group for industry, university, and government collaboration in the HIPing program.

Scientists and engineers may participate in the research effort through the NIST Research Associate Program, which provides

them the opportunity to work at the Institute on projects of mutual

interest with salaries paid by their employers.

For information on the cooperative program to automate the processing of titanium-aluminide

alloys by HIPing, contact: Robert

J. Schaefer, NIST, A153 Materials

BIdg., Gaithersburg, MD 20899,

301/975-6162. R.R. NIST metallurgist Robert J. Schaefer monitors the compaction of rapidly solidified titanium-aluminide metal powders.

13
Exploring Earth's

Formation

ow did the Earth evolve from its beginnings billions of years

ago to the present? Where do deposits of precious metals

come from? How much of the Earth's makeup is from extraterrestrial sources? Researchers are helping to answer these

questions with a custom-made chemical measurement system

used to make unprecedented analyses of rocks and meteorites.

At the heart of the system,

developed by NiST chemist Jack

D. Fassett and Richard J. Walker, a geochemist for the United

states Geological Survey (USGS),

lies a powerful technique known

as resonance ionization mass

spectrometry (RIMS). Among

other things, RIMS enables scientists to measure rhenium and

osmium, two difficult-to-detect ele- ments found in the Earth's rocks. Based on the abundance of the two elements in Earth samples, scientists can accurately determine the age of rocks and

learn much about the history of a

rock sample.

Rhenium and Osmium's Roie

Because rhenium and osmium

are present only in minute quantities in rock samples—lower than

parts per billion in most cases

and because these elements cannot be measured accurately by

traditional methods, the re- searchers have tailored the RIMS

technique to serve these geological purposes. The key to much of the RIMS

research is measurement of specific atoms—isotopes—of the two

elements. The isotope rhenium187 (Re-187) gradually decays

over time and becomes the iso- tope osmium-187 (Os-187). As

time progresses, Re-187 concentration decreases while Os-187 in- creases. In a given rock sample,

the ratios of both isotopes to a

stable (unchanging) reference iso- tope such as Os-186 corre- sponds to a specific period of time. By plotting isotopic ratios of the two elements on a graph,

scientists can calculate the age

of a rock sample.

There are other isotopic

methods for studying and dating

rocks. These are valuable, but they yield different information about samples than the Re/Os

system. Ideally, scientists can

glean the most information from

rock studies by using several iso- topic techniques in unison.

"It's another weapon in the ar- senal," says Walker about the Re/Os method. "Because

rhenium and osmium can date

rocks that other systems can't.

such as those with high concentrations of platinum group ele- ments, they open up a whole

range of new possibilities."

Practicai Applications

Walker, along with colleagues

from USGS and the Carnegie Institution of Washington, recently

used the Re/Os technique in a

study of rock samples from Montana's Stillwater Complex. This

site contains a rich deposit of plat- inum concentrated in a thin layer. Scientists wanted to know why

the metal had congregated in such a small band. The Re/Os

method was called on because of

its special abilities to provide in- formation about platinum and re- lated metals. Employing RIMS

analyses of Re and Os isotopes,

along with other independent

methods, the study confirmed earlier work that a geological phe- nomenon known as "magma

mixing" had occurred. That is, two geochemically distinct mag- mas—molten rock from within the

Earth—blended together nearly

3 billion years ago, causing the platinum deposit to form.

14
Besides being important to geologists charting the Earth's history, the Stillwater study provides

valuable information that can help

locate similar platinum deposits.

Measuring Re and Os with RIMS has proven itself in other in- stances as well: A study in India showed

that the movement of water mobilized certain components of very

old crustal rocks, creating

deposits of gold.

In Ontario, Canada, Walker

and collaborators affirmed other studies showing that a significant

amount of noble metals in the

Earth's mantle was added to the

Earth from extraterrestrial sources

following core formation 3.9 to 4.5

billion years ago. How RIMS Works

The RIMS technique is actually a

marriage of laser technology and

the traditional chemical analysis

method of mass spectrometry. By

nature, RIMS is ideal for analyzing Re and Os. Conventional tech- niques cannot accurately deter- mine Re and Os concentration.

This is because these two ele- ments are in such small amounts

in most samples that they are hard to measure and because of "isobaric interference," a chemistry gremlin that throws off an

analysis by making the concentration of one element appear to be

part of a chemically similar ele- ment's concentration.

A RIMS analysis begins by il- luminating a purified sample with

laser light tuned to an element's "resonance" frequency, or the wavelength at which photons

prompt a given element to ionize. This prepares the sample for

analysis in the mass spectrometer. Since only one element has

been ionized, the instrument can

selectively analyze the concentration of this element with great

sensitivity, allowing minute concentrations to be detected and

eliminating the isobaric interfer- ences of other techniques. To measure a second element, scientists need only to tune the laser to the resonance frequency of that element, then measure it in the mass spectrometer.

For some time, the RIMS in- strument at NIST has been the only one of its kind used in this way, but the idea is catching on. For example, scientists at the Carnegie Institution of Washington are building their own RIMS in- strument for their work in studying

the Earth's geological history.

Others will likely follow suit. What Lies Ahead

NIST researchers are exploring

other ways to use the instrument. One of the most promising is in semiconductor evaluation, where

RIMS has been used to detect impurities that can cause degradation or even the costly scrapping

of a semiconductor device. One

element, vanadium, can fatally contaminate the thin films that coat semiconductors at levels as

low as parts per trillion. The RIMS

technique is especially sensitive

to measuring vanadium at these

levels, and NIST scientists have

successfully used RIMS to analyze vanadium impurities in sample materials. Another potential use is certifying the Standard Reference Materials (SRM's) NIST sells to laboratories to assist in calibrating in- struments and evaluating analyti- cal techniques. RIMS has been

used to measure elements in these materials that other methods can't accurately gauge.

RIMS was used effectively to

certify the concentration of iodine and vanadium in an SRM for oyster tissue samples.

As scientists at NIST continue

to produce data for Earth samples, semiconductors, and

other specimens with RIMS, more ways to use the technique will

likely surface. As Fassett says:

"This method started as an experiment, now it is a workhorse—

a

day in, day out analytical tool that

is very reliable and has many

potential applications."

by John Henkel

NIST Public Affairs Specialist

Richard J. Walker prepares to analyze a rock sample.

15
NIST: Helping

industry To Compete

his past year has probably been one of the more eventful in our

history as we nnade the transition fronn the National Bureau of

Standards to the National Institute of Standards and Technology

Along with that name change, we saw the enhancement of our

traditional measurement research and standards function to include a more general mandate to improve the competitiveness of U.S.

industry. To my way of tliinking, the NIST mission now has three major elements:

measurement—providing the

scientific data and standards that our economy needs to compete

in the world market; technology—assisting U.S. industry to develop and apply

emerging technologies to make

world-class products; and

technology transfer—accelerating the application and wide deployment of new technologies

developed at NIST and else- where, to enhance the competitiveness of U.S. industry.

"Competitiveness" is becoming a cliche, but it has real meaning and real consequences. Competitiveness is the degree to which the United States can pro- duce goods and services that

satisfy customers in the inter- national marketplace while

This article was excerpted from

testimony given by NIST Acting Director Raymond G. Kammer before the Senate Committee on Commerce,

Science, and Transportation on June 6, 1989.

simultaneously Improving our real national income.

Another phrase that is getting a lot of use these days is "world- class products." if the U.S. economy does not succeed

in producing world-class products, our future will be one of decline. World-class products have

the following characteristics: highest quality, advantageous

life-cycle cost, modern features,

and prompt availability in the marketplace. Processes involved in the manufacture of world-class products must share these attributes.

I think the following examples illustrate the intersections between

the expanded NIST mission and

this definition of what U.S. in- dustry desperately needs in order

to market world-class products.

Quality

Motorola, a 1988 winner of the Malcolm Baldrige National

Quality Award, recently did a

survey of the quality of U.S.- produced goods and services.

The result was disquieting. The

usual defect rate, or failure, in U.S. -produced goods and ser- vices is about 6,000 per million actions. The level of performance

that Motorola and a very few

other U.S. companies achieve is more like three defects per million actions, 2,000 times better. This

is the level of quality expected of world-class products.

Many companies now are rec- ognizing that quality requires more than advertising—more

time, more discipline, more measurements, and a more systematic

approach. One encouraging sign

to me is the number of U.S. companies that set out to apply for the Malcolm Baldrige National

Quality Award, which is managed

by NIST, and concluded while studying the application that they were not yet ready to submit to the examination.

Through our discussions

with industry, I conclude that the Malcolm Baldrige National

Quality Award is meeting its in- tended purpose, serving both as an incentive and, more impor16
tantly, a source of education on

quality for U.S. business. Thousands of businesses are now actively using the examination document for self assessment, for

initiating quality systems, for communications and comparisons,

and as an adjunct to education

and training, particularly at the management level. Measurement

Modern instrumentation and applications have approached the limi- tations of supporting national standards in a number of technical areas. A timely example,

which combines developments in electronics with basic standards

and industrial advances, comes

in the area of modern voltage standards. To keep the United

States competitive with other in- dustrialized countries, NIST is exploiting the technology required

to develop superconducting electronics. This program has been

so successful that it has pro- duced the world's most accurate

voltage standards for voltages

up to 12 volts, a voltage range

widely used in electronic

instrumentation. Measurement is also a key ele- ment in quality, and the opportunities and needs in measurement

science have never been greater.

Many of the critical technologies,

such as high-temperature superconductivity and semiconductor

electronics, can only be exploited

through the most exacting applications of measurement science.

Many of the required measure- ment technologies involve, however, industrial and public sector resources of enormous scope

and size. This factor, the diversity

A collaborative effort between NIST and Dionex Corp. resulted in the development of a new

generation of a widely used analytical chemistry instrument. H.M. (Skip) Kingston of NIST (left) and Archava Siriraks of Dionex are shown with the chelation ion chromatography system.

and nature of the measurement

technology, and the speed re- quired to get new technologies to market, all work to ensure that no

single firm or group of firms has

sufficient incentive to produce,

maintain, interrelate, and support

the measurement methods, refer- ence data, and reference materials underlying a critical industrial technology.

Measurement science is critical to the quality of products pro- duced, for example, by the $40

billion per year magnetic recording industry. The density of data

storage on magnetic memory devices doubles roughly every 2V2

years, and now stands at over 10 million bits per square inch. Higher densities reduce both cost and space, and increase effi- ciency. To achieve further in- creases in data storage capacity

and improvements in the perfor- mance of the read-write heads,

and thus in the quality of products, industry must have the ability to visualize the actual size and

shape of individual magnetic bits. A unique device that can do just that—resolve magnetic microstructures as small as 10 billionths of a meter—was

developed at NIST 3 years ago. The device is called a SEMPA, for scanning electron microscope

with polarization analysis.

SEMPA makes it possible for the

first time to map—at the atomic

level—the magnetic characteristics of the surface of materials, for example an entire floppy

disk. This ability is the key to storing more and more information in

less and less space. The NIST device is so good

that industries like Honeywell,

17
Control Data, Westinghouse, and even greater impact on our

Digital Equipment regularly send economic well-being over the

their scientists to use the $3,000/ next several decades than they

day SEMPA facility. In the past have in the past. It is interesting year, NIST researchers have as- to consider the list of major

sisted Perkin-Elmer to design a emerging technologies given in commercial version of the instru- that report: advanced materials,

NIST researchers developed the world's most accurate voltage standard up to 12 volts. Left to

right are Richard L Kautz, Frances L. Lloyd, and Clark Hamilton with an early version of the system.

ment; and its clones are now

beginning to appear in other laboratories, Stanford and MIT to name but two. The key to advanced magnetic recording devices is the kind of quality in product development that the NIST

SEMPA program has helped to ensure. Technology

A Department of Commerce

(DOC) report released in 1987

provided a status and futures assessment of seven of the most

critical emerging technologies.

These technologies will have an

electronics, automation, bio- technology, computing, medical

technology, and thin-layer technology. A report as recent as 1987 d/'dnof include hightemperature superconductors,

although its potential emergence was noted in the report. An oversight? No, the report was in fact quite timely. This is just an ex- ample of how quickly new tech- nologies can develop, and you

may be assured that more sur- prises are out there waiting for us

This report is currently being re- viewed and updated by the Department and NIST. The Secretary specifically charged us with proposing ways in which U.S. in- dustry might be actively engaged

to participate in the study.

About 40 to 45 percent of our

directly funded research effort is devoted to the major emerging

technologies identified in that DOC report. This didn't happen

suddenly, of course; it has been a

studied reaction to the increasing

economic significance of these

technologies. The NIST role in the service of emerging technologies

is in the pre-competitive, laboratory proof-of-concept stage, when

the technology is "generic." A

generic technology is a non- product specific technology that

is widely used by all firms in a particular industry.

A good example in the area of advanced materials is advanced

metals. Conventional production

of advanced materials is labor in- tensive and suffers from high re- jection rates of finished products.

Intelligent processing is a new

computer-controlled approach to producing advanced polymer, ceramic, and metal alloy materials

that are far superior to those in use today. The intelligent proc- essing approach is based on the same concepts on which the NIST Advanced Manufacturing

Research Facility is built. Continu- ous computerized monitoring

during processing allows quality

to be built in, rather than ensured

by post-production testing. (See

article on page 10.) We have also been nurturing

within the Institute a half-dozen

small programs that are develop18
ing capabilities for finding, isolating, and manipulating individual atoms and groups of atoms on

surfaces and in free space. We

have seen "atomic wires" only a

few atoms thick (a single human

hair is a million atoms thick), a

cluster of iron atoms that is per- haps no bigger than a single magnetic bit, and embryonic liquids

and crystals formed from a handful of atoms. This is measurement

science at the frontier—what

NIST scientists do best—re- search that could ultimately have

a major impact on several emerging technologies, including electronics and thin-layer technology.

Technology Transfer

The third element of our mission

is an expanded effort in tech- nology transfer. We have, for ex- ample, selected three organizations to become the first NIST

Regional Manufacturing Technology Centers (RMTC's). The

goal of these new RMTC's is to assist America's small- and midsized manufacturers in becoming

more competitive by upgrading

the technological skills of their workforce and by adopting modern automated manufacturing

technology. This will include,

where appropriate, the transfer of technology from NIST's Auto- mated Manufacturing Research

Facility. Technology transfer often means taking measurement tech- niques off the bench, out of the

laboratory, and into the real world. To us at NIST it also means

serving as a conduit, convener, and often stimulus to voluntary

private-sector standards-setting

bodies, helping them to employ

the latest technical advances with minimal impediments to manufacture and trade. NIST brings to the

table not only technical expertise, but the "third party" objectivity

and lack of proprietary interest essential to rapid deployment and

acceptance of new advances in science and technology.

Some of the keys to prompt- ness to market, particularly for expensive and intricate components that must work well with other products, are product standards, interface standards, and

other agreements and sets of re- quirements that aggregate a

market. The simpler the requirements for a new product, the easier it is to connect with something

already out there, the faster it can

be designed and produced, and

the greater the potential market

for it. PDES, which stands for Product Description Exchange Specification, is an example of how tech- nology, in this case information technology related to the design,

maintenance, and use of databases, is transferred to in- dustry. PDES is intended to pro- vide a standard format for a re- pository of measurement data

about a product—in digital form

that will govern its entire production cycle. The data will describe

such things as geometries (no more blueprints), fit, finish, toler- ances, and complete instructions

for automated manufacture.

PDES is not the data itself, but the

specification of the format for the database. A buyer can then, for example, directly communicate

his needs electronically to a supplier's manufacturing system.

Quality is improved since product

fit and tolerances are encoded

into computerized specifications. Cost is reduced because proc- ess engineering is performed

during the design phase, not

after, and machine setup is auto- mated. Build time and inventory costs can also be reduced be- cause small lots can be more

easily fabricated. At a much more fundamental

level, PDES is an emerging tech- nology that deals with how to rep- resent a// the required knowledge

about the product or process as

data that can be stored, manipulated, and interpreted by machines without human manipulation. PDES is a very sophisticated

technological enterprise that deals, in parallel, with the development of an emerging

technology (knowledge representation) and an emerging stand- ard (a data format). The very unusual parallel development of both a generic technology and a

standard gives NIST a particularly

unique role to play. I am proud to say that the NIST Automated Manufacturing Research Facility is being used as the national testbed for PDES, and that as a

result NIST has led the effort to establish the PDES standard. With our new mandate, we

can aggressively respond to opportunities presented both by the needs of our society and by the constant flux of exciting develop- ments in science and technology.

19
Tracking Time

onald B. Sullivan, chief of NIST's Time and Frequency Division,

is fond of leading visitors behind the scenes of his division's

operations. One place he takes them is a dimly lighted, musty,

underground suite of two rooms. In one room sit two oil-fired

generators, and in the other are row upon row of lead-acid

storage batteries of the kind used to propel golf carts. These are the

backup power systems for the NIST timescale. "You can let a laser-power or a microwave standard go down

for several days and everything is ok. But you can't do that with the

clock; it has to operate continuously. That's why I like to take visi- tors to the battery room, to emphasize this point," says Sullivan. And just what is it that operates continuously—a round wall clock with well-calibrated ticks? A snazzy digital display that reads out in microseconds?

David W. Allan explains the methods used to measure

performance of different clocks and to transfer time

worldwide.

Guess again. The "clock" that keeps most of the United States running on time is a piece of paper. A piece of paper??!!

That's right, a piece of paper that

spits out of a printer in a room

chock full of computer equip- ment. There's not even an old- fashioned wall clock adorning

that sterile room.

But, you argue knowingly,

doesn't NIST have one of the world's most accurate atomic

clocks? Isn't that what is used to set the nation's civilian time?

Well, yes and no. NIST does

have one of the world's most ac- curate clocks (dubbed NBS-6, so named when NIST was the

National Bureau of Standards),

and it does serve as the basis for the timescale. But here's where we let you in on a little secret. NBS-6 is a 20-foot-long stainless

steel tube resting on a huge

table. The metallic element

cesium is cooked at one end of the tube until it is vaporized and

sent rushing down the tube. The

vibrations of the cesium atoms

are counted electronically and,

after more than 9 billion vibrations, 1 second of time has

elapsed. Its accuracy is 1 second

in 300,000 years. That's how

NBS-6 works . . . but NBS-6

hardly works at all. Because NBS-6 was not designed to operate continuously, it

is turned on only about once a

year. For most of the time NIST relies on a series—in timekeeping

jargon an ensemble—of commercial atomic clocks. There are 12 clocks in all, encased in environmentally controlled metal chambers in a lab room across

the hall from NBS-6 and next door

to the sterile computers. And

that's where the paper comes in.

All 12 of the clocks are wired to the computer which every 2 hours

asks each clock its time with re- spect to ail the others. The result

of this interrogation is a number

or more accurately 12 numbers.

These numbers are mathematically and statistically averaged

and the result, which can be

shown to be more uniform than

the best clock in the ensemble, is the official atomic time of NIST. Or is it? Here's where we let you in on

secret number two. There are

several timescales. First there is the timescale that is traceable

directly to calibrations using

20
NBS-6—this is termed atomic

time, TA(NIST). Tlnen there is the raw time generated by the en- semble of commercial cesium

clocks—this is atomic time 1, AT1(NIST). Finally atomic time 1 has added to it or subtracted

from it enough time to make it syn- chronous with the international timescale—this is called universal coordinated time, UTC(NIST),

But wait, there's more. NIST

feeds to the International Bureau

of Weights and Measures (BIPM)

in Paris the readings of its three timescales. BIPM takes the feed

from NIST and 39 other contributing countries, averages them,

and issues the official universal coordinated time. It is all a paper

process; there is no official, physical clock at the BIPM. NIST takes

the data from Paris and once a month uses it to correct—or steer—its own UTC(NIST)

timescale to conform to the inter- national one. But, strangely

enough, by the time NIST re- ceives the Paris data and makes

the adjustments for UTC(NIST),

as many as 2 months have

elapsed. Since most customers

don't want to wait 2 months for the official world time, they take

the best they can get from NIST,

which is usually within one-fourth

to one-half of a microsecond of world time. Who are the people that pro- vide the nation with such accurate time? Before the advent of atomic timekeeping, it was

astronomers who had charge of the world's clocks. Today it is mathematicians, physicists, electrical engineers, and computer experts. At NIST, two of the key players are David W. Allan, a physicist and statistician, who has per- fected the mathematical formula—

or algorithm—that is the basis of the paper clock, and Judah

Levine, another physicist who is an expert in computer hardware

and software. According to Levine, the differ- ent timescales are driven by the needs of different users. The tele- communications industry, for in- stance, wants a timescale that is linked to the Earth's rotation or, in Levine's words, a timescale

where, at noon, "the sun is over- head." These users receive the NIST version of UTC. A radio astronomy observatory or a frequency counter manufacturer,

for example, is interested in atomic time, AT(NIST), because

their real requirement is fre- quency stability. Since AT(NIST),

is derived from NBS-6, it provides

the best frequency count currently obtainable. "What you want

to know is that after 9 billion oscillations of the cesium atom ex- actly 1 second has elapsed.

You're not interested in the time

of day," Levine notes, adding that

this scale "is most useful for cali- brating secondary frequency

standards."

It is Levine's job to keep the computer up to the job of maintaining the various timescales. "A monster computer program runs

all of these processes. It continually looks at the algorithm and

monitors the clocks for their

'health.' It may automatically take one clock off-line if it misbehaves," Levine says. The computer has been known to fail but

Physicist David J. Glaze adjusts NIST's newest atomic

clocl(—NIST-7.

not the clocks. "The software crashes about twice a year and we lose our real time capabilities.

We've lost our ability to tell you

what time it is but the clocks

haven't stopped," Levine adds.

When the computer comes back

on-line it picks up the count from

the continuously operating clocks.

Additionally, one of the cesium clocks has a steered out- put which is kept within one-half a nanosecond (billionth of a sec- ond) of the computed scale. If the computer goes down, this steered clock wanders away from

computed time very slowly—on

the order of 1 nanosecond per

day. NIST's primary time dissemination services are not affected by such computer glitches. Radio

stations WWV (Fort Collins, Colo.)

and WWVH (Kauai, Hawaii),

where most users get their time in- formation, have their own cesium

clocks which are coordinated

with the time scale but are not dis- turbed by computer failures; the

satellite time service is not af- fected either.

21
Levine is currently overseeing a switch of computer systems.

The old computer does not have

enough data analysis capability

and has become costly to maintain. The new computer system is being installed, and both systems

will run in parallel for 3 or 4

months until all the bugs are worked out. Just as important as the computer system is the algorithm that combines the data, makes al- lowances for errors and biases.

and comes up with a paper time.

"If you design the algorithm right, you can have a time output that's better than any one clock individually," says Allan, adding, "each

time I add information to the sys- tem, I know more ... the sum

is better than any one of its parts." Allan says it almost doesn't matter whether he adds a "good"

or a "bad" clock to the system, so

long as the performance of the new clock is well known before it

is added to the ensemble. The

algorithm he has developed as- signs weights to each clock in the system, so a clock that is inherently less stable will be assigned

a much lower weight. Once part

of the ensemble, the clock's per- formance is carefully monitored

for changes over time, and these

changes are factored into the

formula. Because the paper time

output is better than any one of the clocks in the ensemble, a

physical clock is adjusted periodically so that it is kept within

NIST Time and Frequency Services

How does NIST disseminate its time and frequency information?

The oldest and most popular service is radio station WWV, near Fort Collins, Colo., which has

been broadcasting since 1923. It covers the conti- nental United States and broadcasts at 2.5, 5, 10, 15, and 20 MHz on the short-wave band. A sister

station, WWVH, broadcasts to the Pacific basin

from Kauai, Hawaii, on all but the 20-MHz

frequency. The broadcasts include standard

frequencies and time intervals, the time (both

voice and digital code), astronomical time corrections, and public service announcements, such

as marine weather, geophysical alerts, and radio propagation information. The accuracy of these

broadcasts, as received, is between 1 and

10 milliseconds. A telephone time service, which

carries the WWV broadcast, is available by dial- ing 303/499-71 1 1 (atoll call). Another NIST radio station, WWVB, broadcasts a digital time code at the standard fre- quency of 60 kHz. Also located near Fort Collins,

this low-frequency station, which covers the conti- nental United States, has an accuracy for time

comparisons of between 0.1 and 1 millisecond.

Its 60-kHz carrier frequency can be used for frequency calibrations with an accuracy of better than 1 part in 100 billion.

NIST also disseminates time code information

via satellite, utilizing two National Oceanic and At- mospheric Administration GOES weather satellites. The coverage includes North and South

America plus portions of the Atlantic and Pacific oceans. This digital time code is accurate to within 100 microseconds, depending on knowledge of the position of the satellite. The newest dissemination service, the Auto- mated Computer Time Service (ACTS), which just

completed its first year of operation, provides

millisecond accuracy for computer clocks and

other digital systems using telephone lines. This

service includes automatic compensation for telephone-line delay and advanced notices for changes to and from daylight savings time as

well as leap seconds.

Who uses these services and why?

One major user is the communications industry.

Radio and television stations use WWV and

WWVB to maintain accurately their allocated frequencies to comply with Federal Communications Commission regulations. Networks and sta- tions time their broadcasts via WWV, WWVB, or GOES. Telephone companies use the radio stations to set their time-of-day services and to time

22
one-half of a nanosecond of the paper clock. In Allan's terms, the steered clock "chases" the paper

clock. "We are virtually unique in that respect," he says, noting that many other countries prefer to have a physical—versus paper

clock as their final timekeeping

output. Two nations that have

elected to go the paper route and

have adopted variant versions of Allan's mathematical formula for

their timekeeping systems are

Israel and Switzerland. A similar

algorithm is being developed by

the U.S. Air Force for its own

timing purposes. Can the NIST timescale sys- tem be improved? The answer is a resounding "yes!" In the next 2 years, NIST hopes to bring online its newest atomic clock

NIST-7—which will replace NBS-6

as the nation's primary standard.

NIST-7, which is now in the final stages of construction and test- ing, will improve long-term stability and frequency uncertainty

by tenfold; it will be accurate to 1 second in 3 million years. A

cesium clock, it will use laser

light instead of magnetic fields for atom state selection. "NIST-7 will run more continuously because it can estimate errors more easily," says Sullivan. This more frequent

operation will add more data

points to the algorithm for averaging the NIST timescale, making it more accurate and reliable than

ever. F.M.

long-distance calls. In still another application, the New York City Fire Department uses a commercial WWVB receiver to insert a time code on

all of its 91 1 emergency calls. NIST time and

frequency dissemination services are also used

to synchronize data transmissions.

The electric power industry is another major

user of NIST services obtaining a master time ref- erence for its transmission grid, a frequency refer- ence to maintain accurately the power frequency

at 60 hertz, power flow monitoring, fault analysis,

and precise characterization of power networks

for stability analysis. One power company uses WWVB to synchronize data transmissions from

15 substations that feed data into a central data

bank.

The transportation industry depends on NIST

to provide a time reference for scheduling rail- road operations, as a tinne base for Federal Aviation Administration voice recorders in airport control towers, for air traffic control operations and

analysis, for cockpit flight recorder timing, and for automatic synchronization of traffic light operations. In the latter application, the County of Los Angeles recently purchased 1,000 commercial

traffic-light controllers, all of which derive their time from WWV, to regulate traffic flow along busy

commuter corridors. WWV receivers are common on larger ships as part of a timing reference for electronic navigation systems; pleasure boaters also use WWV re- ceivers as a time reference for celestial navigation. The United States Coast Guard uses WWVB

receivers on all of its ocean-going ships for frequency and time control. Other users of NIST time services include oil exploration and drilling companies for position lo- cation, private and government calibration laboratories for calibration of various pieces of hightech equipment, the national space agency for timing of various deep space missions, the music

industry for standard musical tones, and law en- forcement agencies for the calibration of tuning

forks used with radar speed guns. One interest- ing user of the WWVB sepi/ice is Walt Disney

World in Orlando, Fla., which uses one WWVB re- ceiver to set time for its primary computer system

and another to time all of the various shows and

animation sequences in the sprawling theme park.

How can I get more information about tiiese

NIST services?

For general information about NIST time dissemination services, contact Roger E. Beehler, NIST,

Time and Frequency Division, Boulder, CO

80303, 303/497-3281 . For software to access the Automated Computer Time Service, contact the

Office of Standard Reference Materials, NIST,

B31 1 Chemistry Building, Gaithersburg, MD

20899, 301/975-6776; ask for product RM8101.

23
Movies Reveal

Secrets of Materials

rialsngineers at the National Institute of Standards and Technology

in Boulder, Colo., are in the movie business—but their objective

is not to pack in theaters. Using supercomputers and fancy

computer-generated graphics that would impress Hollywood,

they are trying to understand better how new composite mate-

-particularly graphite epoxy—stand up under stress and strain.

With sophisticated mathematical

modeling techniques, they are able to simulate a stress wave

moving through a piece of graphite epoxy and—for the first time—view the progression of this wave in three dimensions from

different planes and perspectives.

They are focusing their initial

efforts on graphite epoxy be- cause it is coming into widespread use in the aerospace

and defense industries. An ex- tremely lightweight but stiff and

durable new material, it is used

extensively on the Air Force's new

stealth bomber, and the Navy is considering using 20-inch-thick

layers of graphite epoxy for the

hulls of submarines. Of particular

interest to the military is the

fact that graphite epoxy

absorbs radar and

sound waves.

making the material "invisible" to detection.

Oil companies are also inter- ested in using graphite epoxy for tethers on deep-sea oil-drilling platforms. The tethers need to be

stiff to keep the platform stable and strong enough not to break

under the tremendous pressure. "We are looking for ways

to evaluate this material nondestructively. One way is to

This computer- ^^sa^i^a^ generated diagram stiows a stress wave moving along the fiber orientation in a uni- directional graphite/epoxy composite. Each of the five humps represents one of the periods of the urave and the ripples

coming off of these periods.

24
put transducers on the material to show how the stress waves propagate through the material," says Ronald D. Kriz, a mechanical en- gineer in NIST's Fracture and

Deformation Division. If graphite

epoxy were a clear material, it would be possible physically to see the waves moving through. But because it is opaque, Kriz has had to resort to computer

simulation of the stress waves. Working with John M. Gary of the Scientific Computing Division, Kriz developed a simulated block

of graphite epoxy containing

80,100 elements. A sound wave

was "passed through" the block,

taking almost 3 hours to propagate and using up virtually all the memory of NIST's supercomputer. When the results of the computer simulation were compared with theoretical models,

there was a difference of less than 2 percent, giving Kriz and

Gary confidence that their method was valid. More recently, Gary has come

up with new numerical tech- niques that have reduced the

time to propagate a wave through

the simulated material to 40 sec- onds and to use much less computer memory.

Using advanced computer

graphics, they are able to convert

their data into moving repre- sentations of the wave passing

through the material. "By converting to a movie, we are able to confirm what has been assumed

about wave propagation but never visualized before," says

Kriz. One pulse sent through the

material breaks into two waves

one shear and one longitudinal.

Once they reach the edge of the

block, they bulge slightly and are

reflected back along the same

path. One small wave, apparently a reflection, goes off in another

direction. "This was not predicted," says Kriz. Movies give the researchers

perspectives that were never

available before. The more movies they make and the closer they

inspect them, the clearer things

become. "The simulation is starting to make sense concerning what we measure in the laboratory," Kriz notes. A little blip in a wave pattern that showed up on a

static diagram now can be traced as a break-off wave and followed dynamically through its cycle.

"By converting to a movie, we are able to

confirm what lias been

assumed about wave

propagation but never

visualized before."

"I never saw the connection

between the Rayleigh surface waves and the wakes of the prop- agating bulk waves before," Kriz says, adding, "I never realized these two phenomena were connected. This simulation clearly

shows the connection between

these two phenomena."

"The purpose of the simulation

is to aid in the design of new nondestructive evaluation (NDE)

techniques for these composite

materials," Kriz notes. Working

with NDE design engineers, Kriz

will be able to predict where the sound wave will go, the shape of the wave, and the time it will take

to propagate and reflect back.

"Before, this was done by trial and error techniques," Kriz says.

In many ways, the NIST re- searchers are blazing new trails

in the way that scientific data are presented. For many portions of

their work, videocassette tapes

are more important than written re ports with static diagrams. They

are sharing these tapes with col- leagues in the same field of re- search and have been asked to present their movie results at two

conferences: The International Union of Theoretical and Applied

Mechanics conference on elastic wave propagation and ultrasonic nondestructive evaluation at the

University of Colorado and the Re

view of Progress in Quantitative

Nondestructive Evaluation in Brunswick, Maine.

The next step is to go to a more advanced computer, called a connection machine, which

may reduce the processing time

to less than a second and enable

the block of graphite epoxy to be

projected in a three-dimensional,

cube perspective. Kriz and Gary

also have been working with two

Boulder computer graphics companies. Precision Visuals, Inc., and G.W. Hannaway and Associates, to improve the quality of

their movies. F.M.

25
Technique Sterilizes

Ciinicai instruments

in Seconds

he time needed to sterilize dental and medical instruments now

can be reduced from hours to seconds by an innovative process developed by scientists at the National Institute of Standards

and Technology. The new sterilization method completely disinfects instruments in 30 seconds when they are treated by

a microwave-generated gas plasma. The gas plasma is produced in a

container that holds the contaminated instruments inside a conventional microwave oven. The technique should help

health-care professionals improve

patient care, and it may reduce

the damage to expensive instru- ments caused by repeated exposure to time-consuming, traditional sterilization methods.

Two NIST scientists,

Waldemar de Rijk, dentist and

physicist, and John A. Tesk,

leader of the dental and medical

materials group, collaborated on

the microwave sterilization project.

The scientists have filed a

patent application, and de Rijk is working with other researchers to measure how the treating proc- ess affects various materials and

microorganisms. He also hopes

to work with industry to develop a

practical sterilizing appliance in which a gas plasma can be used

routinely in health-care facilities.

De Rijk says, "We are inter- ested in producing a simple sterili- zation method that will be aseasy to use as a household micro- wave oven," He emphasizes

that the new process offers an

Waldemar de Rijk, front, and John A. Tesk sterilize clinical instruments with

their new microwave-generated gas plasma method.

26
inexpensive and rapid way to

sterilize instruments. TInis is important because some tools are re- used more than 10 times each

day.

It is estimated there are approximately 80,000 sterilizing

apparatuses in dental offices,

clinics, hospitals, and other health-care facilities throughout

the United States. Most sterilizers are either dry heat or steam autoclave, with the latter being the most common. Both processes

take 1 1/5 to 2 hours to complete a

sterilization cycle.

Continued heat sterilization can take its toll on equipment.

The rubber seals and gaskets in most dental handpieces fail when

exposed to dry heat at temperatures of 160 to 170 °C. Repeated

steam-autoclave exposure at temperatures of 120 °C or more

can dull the cutting edges of dental metal burs used for cavity

preparation. These high temperatures also can anneal metal instru- ments, changing their strength

and hardness.

Despite these shortcomings,

De Rijk says the detrimental ef- fects from high-temperature

processes are preferred over

alternative cold chemical treat- ments which may not destroy all of the microbial spores and

viruses on instruments.

In addition to conventional

sterilization methods, gas

plasmas generated by radio- frequency electromagnetic waves

also have been used to destroy

organic matter on mirror-smooth

surfaces. Tesk and de Rijk de- cided to investigate microwave

technology because it could be

more effective and easier to adapt for health-care use. But first the scientists had to

find a way to treat metal instru- ments in a microwave unit without the severe arcing that can damage the magnetron energy

source in the appliance. The

Initial trials show

it is the gas plasma

that Idllsallof the

organisms on artificially contaminated

instruments.

problem was solved by placing metal instruments in a glass container inside a microwave oven and then evacuating the air in the container to create a low vacuum

or a rarified atmosphere. When

microwaves are applied, the at- mosphere is ignited and be- comes a low-pressure ionized gas that destroys the microorganisms. The gas plasma pre- vents the electric arcing of metal

objects.

The scientists found that both metal and nonmetallic in- struments can be sterilized by

the new microwave process. De Rijk points out that even after

1 minute of exposure, the sur- faces of the instruments are heated to no more than 60 °C, a temperature much lower than conventional heat processes. "We

are speculating that the microorganisms are being killed by ion bombardment in the plasma

which 'denatures' or destroys

their protein," says de Rijk. Other explanations are being

investigated.

Initial trials show it is the gas

plasma that kills all of the or- ganisms on artificially contaminated instruments. Previous ex- periments with test strips with microbial spores and contaminated instruments revealed that organisms can survive micro- wave radiation alone or in a vacuum without the radiation. Both are required to produce the gas plasma. Biological studies on

test spore strips and contaminated instruments are being con- ducted for NIST by Lance L. Forsythe and Mark D. Gilberts of the U.S. Naval Dental School in Bethesda, Md.

Tesk says, "The new micro- wave radiation sterilization method for dental and medical

instruments is an example of how

our research can improve the

safe, efficient, and economical

use of dental and medical materials and instruments to benefit consumers and health-care

professionals."

The NIST microwave radiation research project is supported in part by the National Institute of Dental Research (NIDR), one of the National Institutes of Health, a primary sponsor of dental re- search and related training in the United States. For information on the microwave-generated gas plasma

sterilization process, contact: John A. Tesk, NIST, A143 Poly- mer BIdg., Gaithersburg, MD

20899,301/975-6801. R.R.

27
Can Smoke Control

Systems Save Lives

and Property?

Smoke is a killer. Just minutes after most fires start, it can be

moving steadily through a building, clogging stairwells and hallways, cutting off escape routes, and inhibiting fire fighting.

Each year, fires in the United States take nearly 6,000 lives. Yet,

contrary to what people might think, these deaths are not all caused by fire and flame. Data compiled by the National Center for

Health Statistics indicate tinat smoke inhalation deaths exceed

burn deaths by a margin of roughly two to one.

In theory, smoke control sys- tems can protect life and property

by producing pressure differ- ences across barriers, such as

walls, floors, ceilings, and interior partitions of the building, to restrict smoke movement and direct

it away from the inhabitants. However, the technology is relatively

young and is based primarily on

engineering principles and judg- ment. To be sure the systems really protect building occupants

from deadly fumes, NIST re- searchers conducted the first known full-scale tests in the United states of these systems.

"The theory is they will work," says mechanical engineer John

Klote, head of the research proj- ect at the NIST Center for Fire Research. "But the reality is they've

never been tested under full- scale conditions either in a simulated situation, such as we've

done, or during a real-life fire," he said. The NIST tests were con- ducted in the former Plaza Hotel, a seven-story building in Washington, D.C., which is scheduled for demolition. The researchers

burned stacks of wood placed in

. . . NIST researchers conducted the first

known full-scale tests

in the United States of

these systems.

a second-floor room to simulate a

fully involved fire in a furnished room. Using large fans and

ducts, the floors above and

below the fire floor and the stair- well were pressurized. This

helped confine the smoke to the

fire floor from which it was ex- hausted to the outside. Much of the air-handling equipment used

for this project was loaned to NIST by the Air Movement and

Control Association, Inc. Other

groups sponsoring this research were the Architect of the Capitol;

American Society of Heating, Refrigerating, and Air-Conditioning

Engineers, Inc.; Bell Atlantic Tele- phone Company; New Jersey Bell Telephone Company; U.S. Fire Administration; U.S. Veterans Administration; and US West, Inc. For the course of the NiST

experiments, the building was

fitted with instruments—video cameras, thermocouples, and

smoke meters—to trace the flow

of smoke and measure its composition, density, and temperature. Natural ventilation flows in the building, which can cause smoke to move up or down stair28
wells and elevator shafts, were ex- amined. The fire itself was monitored to determine its heat output

and rate of fuel consumption. In addition, in one experiment, the NIST researchers examined the

effect of a sprinkler on the fire and smoke spread when the smoke control system was in operation. All of these measure- ments were recorded on a data

acquisition computer, and video

recordings documented events at key locations. NIST's research results will be

used to evaluate current guidelines for smoke control systems,

including those developed in 1983 by NIST in conjunction with

scale physical models can predict accurately the behavior of a

full-scale system in a building.

The computer models are being developed by the NIST

Center for Fire Research to predict fire and smoke movement

through a building and the vulnerability of occupants to fire. These

models make it possible to dupli- cate, within a limited budget, real

fire situations. It is far less costly

and far more practical to "burn" a room or building using a computer. Several models are avail- able and can be used on per- sonal computers. The NIST Fire Simulation Laboratory gives the

fire protection community, as well

Located on the first floor of ttie hotel was the data acquisition computer where

John Klote (standing), Richard Zile (seated left), and Darren Lowe monitored

events during the fire.

the American Society of Heating,

Refrigerating, and Air-Conditioning Engineers, Inc. The information also will be used to develop

and validate computer models

and to determine whether smallas architects, codes officials, and

others, the opportunity to learn about these models and obtain "hands-on" experience.

The NIST Center for Fire Re- search investigates the scientific principles that govern the phenomena of fire, providing knowl- edge for fire safety; develops the underlying technical support for new safety standards; and generates the engineering methods

needed to support the practice of

fire protection engineering.

NIST'S research

results will be used

to evaluate current

guidelines for smoke

control systems. . . .

NIST scientists and engineers

conduct research on how fires

start and spread and how they can be detected and suppressed. This research leads to

realistic material test methods,

cost-effective fire safety design

concepts, and new methods of

fire control and extinguishment.

Some of the research being con- ducted at NIST includes studies on the physics and chemistry of

fire, flame spread, sprinkler sys- tems, the lethal effects of smoke,

and the heat given off by furniture and wall coverings.

NIST does not promulgate or enforce standards or regulations.

It provides technical support to voluntary standards and model

codes groups, the engineering

and design community, the

building industry, fire services,

and fire protection organizations.

It also provides scientifically

based recommendations to other government agencies that have fire safety or regulatory

responsibility. J.K.

29
NewPublications

1989 Directory of NVLAP

Accredited Laboratories

Donaldson, J.L. and Horlick, J., Natl. Inst. Stand. & Tech. (U.S.), NISTIR 89-4056,

56 pages (April 1989). Order by stock

no. PB 89-189278 from NTIS, $15.95

prepaid.

About 200 labs nationwide and

abroad are listed here that are accredited by NIST for specific test methods in various fields of testing as of

April 1 , 1989. The current fields are

acoustics; carpet; commercial products—paint, paper, plastic, and seals and sealants; computer protocols; construction testing services—concrete, ce- ment, aggregates, soil and rock,

admixtures, geotextiles, road and

paving; personnel radiation dosimetry;

electromagnetic compatibility and tele- communications; solid fuel room heaters; and thermal insulation. The labs are

listed alphabetically by name, field of

testing, and state. For information on NVLAP programs, including the new bulk asbestos analysis program, contact: National Voluntary Laboratory Accreditation, NIST, A124 BIdg. 41 1 , Gaithersburg, MD 20899, 301/975-4016.

The Effect of Chinese

Standardization on

U.S. Export Opportunities

Lin, Y., Natl. Inst. Stand. & Tech. (U.S.), NISTIR 88-4000, 15 pages (December

1988). Order by stock no. PB 89- 166128/AS from NTIS, $6.95 prepaid.

Technical information exchange pro- grams between the U.S. and the People's Republic of China (PRC)

and more U.S. trade missions to China

will encourage the adoption of U.S. stand- ards as well as increase trade between

the two countries," says Yan Lin, NIST

guest scientist, in this publication. Lin, from the China Electronics Standardization Institute, describes for U.S.

electronics manufacturers and exporters

the standardization system as it exists in the PRC and reports on the role of the China State Bureau of Standards in the standards coordination process. "U.S. trade missions can expect great success

if the Chinese government agencies con- cerned with major joint venture projects are shown that solutions to their major

problems and expertise suiting their inter- ests are available from U.S. companies,"

says Lin. Information on the impact of China's quality program on U.S. export

opportunities also is included.

Theory and Measurements of

Radiated Emissions Using

aTEIVI Cell

Koepke, G.H., Ma, M.T., and Bensema,

W.D., Natl. Inst. Stand. & Tech. (U.S.), NIST Tech. Note 1326, 40 pages

(January 1989). Order by stock no. 003-

003-02932-7 from GPO, $2.25 prepaid.

Transverse electromagnetic (TEM)

cells are used widely for establishing a known electromagnetic

field for susceptibility testing and

antenna calibrations. This publication

offers theoretical information and some

practical tips for using TEM cells. The re- port addresses mechanical requirements

for positioning the test equipment inside the cell, problems associated with cables, single- and multi-frequency measurements, and use of a computer system

for automated measurements.

Stable Implementation

Agreements for Open Systems

Interconnection Protocols

Boland, T., editor, Natl. Inst. Stand. &

Tech. (U.S.), NIST Spec. Pub. 500-162,

508 pages (December 1988). Order by

stock no. 003-003-02921-1 from GPO,

$26 prepaid.

The second version of stable im- plementation specifications for OSI

(Open Systems Interconnection)

protocols has been agreed to and is available. These agreements are based

on recognized international OSI stand- ards and were reached by vendors and

users participating in the NIST Workshop

for implementors of OSI. They support

the second version of the Federal Infor- mation Processing Standard for GOSIP

(Government Open Systems Inter- connection Profile), which is expected

to be proposed later this year. The

agreements are considered advanced

enough for use in product and test suite development.

NBS Reactor: Summary of

Activities—July 1987 through

June 1988

O'Connor, C, editor, Natl. Inst. Stand. &

Tech. (U.S.), NIST Tech. Note 1257,

227 pages (January 1989). Order by

stock no. 003-003-02920-3 from GPO.

The National Institute of Standards

and Technology (formerly National Bureau of Standards) reactor serves the needs of NIST, other govern- ment agencies, and outside organizations as a national center for the

application of neutron methods to problems of national interest. Operating at 20 MW, the Institute's reactor supports

25 experimental facilities, ranging from in- tense neutron beams to extensive irradia- tion facilities. A major expansion of the experimental facilities is currently under

way. A cold neutron source has been installed, and construction of a large neutron guide hall is completed. The

guide hall will accommodate 15 new in- struments. This will be a national facility providing state-of-the-art instruments that are currently unavailable in the United

States. This report summarizes work accomplished in the period July 1987 through

June 1988. The programs cited range

30
from the use of neutron beams to study

the structure and dynamics of materials through nuclear physics and neutron standards to sample irradiations for acti- vation analysis, isotope production, neutron radiography, and nondestructive

evaluation.

GATT Standards Code Activities

of the National Institute of

Standards and Technology 1988

Overman, J.R., Natl. Inst. Stand. & Tech.

(U.S.), NISTIR 89-4074, 38 pages

(March 1989). Order by sending a self- addressed mailing label to the Office of Standards Code and Information, NIST,

A629 Administration BIdg., Gaithersburg,

MD 20899, 301/975-4037.

The NIST Office of Standards Code

and Information (SCI) serves as

the U.S. GATT (General Agreement on Tariffs and Trade) inquiry point

for information on standards and certifica- tion activities that might significantly affect U.S. trade. This publication describes SCI's activities over the past

year. These include coordination of comments on foreign regulations, translations

of foreign texts, and the operation of the GATT "hotline" (301/975-4041, not toll free) that provides the latest information on notifications of proposed foreign regulations issued by the GATT Secretariat in Geneva, Switzerland. SCI also provides

technical assistance to the Office of the

U.S. Trade Representative in developing

proposals to enhance the Standards

Code. Special reports include the recent summary of European Community plans

to achieve an internal market by 1992

and the standards-related implications of such a program on U.S. exports.

Description of the SRM 1965

Microsphere Slide

Hartman, A.W. and McKenzie, R.L., Natl.

Inst. Stand. & Tech. (U.S.), NIST Spec.

Pub. 260-107, 67 pages (November

1988). Order by stock no. 003-003-

0291 1-4 from GPO, $3.75 prepaid.

Aseries of microscope experiments for students is described

in this report on the construction,

preparation, and recommended uses of Standard Reference Material (SRM)

1965, Microsphere Slide, 10-Micrometer

Polystyrene Spheres. The SRM is a

microscope slide with the first commercial product made in space—the 10-micrometer polystyrene spheres

deposited on it. The SRM is an education

tool as well as a standard to calibrate microscopes for small particle measurements. The spheres are arranged in two

types of groupings. One is an "un- ordered" arrangement, resembling

strings of beads. The other grouping is an "ordered" two-dimensional hexagonal

array for use as a microlength standard

and to act as a "stage" micrometer.

Center for Radiation Research

1988 Technical Activities

Kuyatt, C.E., Natl. Inst. Stand. & Tech.

(U.S.), NISTIR 88-3869, 261 pages

(November 1988). Order from the Center

for Radiation Research, NIST, C229

Radiation Research BIdg., Gaithersburg,

MD 20899, 301/975-6090.

Interaction of radiation with matter cuts a broad swath across science and

technology, with applications—or implications—in the development of advanced materials, electronic components

and technology, biotechnology, thin- layer technology, and medical tech- nology. A report from NIST details the agency's 1988 research activities in all these areas, as well as in the more

fundamental task of making and providing accurate measurements across the

optical and ionizing radiation spectrum.

The report summarizes the technical activities of the five major divisions in the

NIST Center for Radiation Research as

well as consultation services, participation on technical and professional committees, invited talks, and technical

publications.

An Electrochemical Technique for

Rapidly Evaluating Protective

Coatings on Metals

Lin, C. and Nguyen T., Natl. Inst. Stand. &Tech. (U.S.), NIST Tech. Note 1253,

23 pages (October 1988). Order by

stock no. 003-003-02910-6 from GPO,

$1.50 prepaid.

NIST researchers have developed

a fast, reliable technique for eval- uating the performance of or- ganic coatings used for controlling metallic corrosion. In addition to being a

threat to the safety and reliability of struc- tures and products, metallic corrosion an

nually costs the United States an

estimated $160 billion. About one-fourth

of this cost is for paints, platings, or other surface coatings used to combat corrosion. While other evaluation methods are

available, they often are time consuming,

sometimes taking months, or may require

expensive equipment. The new NIST

electrochemical technique is quick

(15 minutes to several hours depending

on the coating), reproducible, and

causes very little perturbation to the coating. In addition, the testing procedure is simple and uses commonly available

instrumentation.

Ordering Information

To order publications from NTIS, send re- quest with payment to: National Technical Information Service, Springfield, VA

22161. Publications can be ordered from

GPO by mailing the order with payment

to Superintendent of Documents, U.S. Government Printing Office, Washington,

DC 20402.

31
Conference Calendar

12th International Symposium

on Polynuclear Aromatic

Hydrocarbons

NIST, Gaithersburg, MD

The major focal point for multidisciplinary

research on this important class of chemical species, this symposium encourages

open discussions among scientists repre- senting government, academic institu- tions, industry, and research facilities in- vestigating the chemical properties and

biological effects of these compounds.

The 1989 meeting will include presentations on parent hydrocarbon PAH's as weW as heteroatomic species and PAH

derivatives including amino, nitro, and

halogen substituted compounds. Topics

include adducts, bioactivity, carcinogenesis, mutagenicity, cell transformation, detoxification, epidemiology, pollution modeling, occupational exposure,

organic synthesis, and environmental

studies. Sponsored by NIST, the National

Institutes of Health, and Battelle Memorial Institute. Contact: Willie E. May, NIST,

A113 Chemistry BIdg., Gaithersburg, MD

20899,301/975-3108.

October 2-6, 1989

Atomic Processes in Plasmas

NIST, Gaithersburg, MD

Among the subjects to be discussed at

this biennial meeting of international ex- perts are atomic processes relevant to plasma applications, such as material processing by plasmas, x-ray lasers, fu- sion, and astrophysics. This conference

combines the series previously known as

the APS Topical Conference on Atomic

Processes in High-Temperature Plasmas

with the International Conference/Workshop on the Radiative Properties of Hot Dense Matter. Sponsored by the American Physical Society, the Department of Energy, and NIST. Contact: Yong-Ki Kim,

NIST, A267 Physics BIdg., Gaithersburg,

MD 20899, 301/975-3203.

12th Computer Security

Conference—Information

Systems Security: Solutions for

Today, Concepts for Tomorrow

Baltimore Convention Center, Baltimore, MD

This conference provides a forum for the government and private sector to share

information technologies, present and fu- ture, that are designed to meet the ever- growing challenge of telecommunications and automated information systems

security. The conference will offer multi- ple tracks for the needs of users, vendors, and the research and development

communities. Topics will include: sys- tems application guidance, security education and training, evaluation and certifi- cation, innovations and new products,

management and administration, and dis- aster prevention and recovery. Sponsored by NIST and the National Computer Security Center. Contact: Irene

Gilbert, NIST, A254 Technology BIdg.,

Gaithersburg, MD 20899, 301/975-3360.

November 20-22, 1989

Reducing the Cost of Space

Infrastructure and Operations

NISI, Gaithersburg, MD

Entrepreneurs at this conference will dis- cuss methods of reducing the cost of commercial enterprise in low-Earth orbit. The great cost of space infrastructure and operations is presently limiting the

extent of commercial participation in space activities. Meanwhile, the private sector is being urged to make major investments in space activities while working to reduce launch fabrication and

operations costs. In order to develop rec- ommendations on future industrial activity in low-Earth orbit, this conference will consist of keynote presentations on

major topical areas and a follow-up workshop in each area. A draft report on each

workshop will be presented at the end of the conference. Sponsored by NIST and

the Office of Space Commerce of the Department of Commerce. Contact: William Stone, NIST, B168 Building Research

BIdg., Gaithersburg, MD 20899,

301/975-6075.

February 5-8, 1990

Fourth International Symposium

on Biological and Environmental

Reference Materials—BERIVI-4

Sonesta Village Hotel, Orlando, FL

The major aim of these symposia, held approximately every 2 years, is to bring

together efforts in the production, study,

and use of reference materials in the analytical, biological, biomedical, clinical, environmental, and nutritional communities.

The third symposium, held in May 1988

in Bayreuth, Bavaria, FRG, provided an

opportunity for attendees to exchange

ideas and views on a variety of topics.

This fourth symposium is expected to broaden these discussions as well as

focus on more specific aspects of future research on problems and projects dis- cussed at the previous symposia. Sponsored by the Department of Agriculture, the Department of Commerce, NIST, and

the Food and Drug Administration. Contact: Wayne R. Wolf, NIST, 8311 Chemistry BIdg., Gaithersburg, MD 20899,

301/975-2030.

32

U,S DEPARTMENT OF COMMERCE

National Institute of Standards and Technology

Gaithersburg, MD 20899

OFFICIAL BUSINESS

Penalty for Private Use, $300

BULK RATE

POSTAGES FEES PAID NIST

PERMIT No. G195