**SECTION 2**

**BERYLLIUM PRODUCTION**

Brush Wellman=s Elmore, OH plant is the only facility in the United
States that produces beryllium metal. The company produces beryllium
hydroxide at its Utah mining and extraction operation and ships it the
Elmore plant where it converts it into beryllium metal. The Elmore plant
also produces beryllium oxide for use in ceramic applications. In all,
Brush Wellman operates four manufacturing facilities that handle
beryllium, including an alloy rolling and drawing mill in Reading, PA; a
ceramics facility in Tucson, AZ; and a facility producing specialized
beryllium products (e.g., X-ray lenses) in Fremont, CA.

Beryllium production at Brush Wellman=s Elmore facility is classified in
NAICS 331419, Primary Smelting and Refining of Nonferrous Metals.
Because it is the only beryllium producer, the NAICS data are not
indicative of the population of facilities with potential beryllium
exposures and are not presented.

The Elmore facility is an integrated facility that encompasses
activities beyond beryllium production. Besides producing pure beryllium
and beryllium oxide, a large part of the operation is devoted to
manufacturing a range of beryllium alloy products. Because of Brush
Wellman=s integrated nature, the activities at the Elmore and Reading
plants overlap some of the other industry sectors addressed by this
report.

**2.1 NUMBER OF EMPLOYEES**

In 1996, Brush Wellman employed 655 workers at its Elmore plant (Kreiss,
et al, 1997).[^1] In addition to the workers involved in beryllium
production, the employment total includes administrative, research, and
maintenance personnel, as well as workers producing beryllium alloys and
beryllium oxide product. Based on visits by its consulting personnel,
ERG estimates that 800 people worked at the Elmore plant in 2000, but
that the economic downturn in 2001-2002 has reduced employment to
between 600 and 650, as of the spring of 2002. Table 2-1 shows the 1999
staffing levels by department at the Elmore plant.

  -----------------------------------------------------------------------
  **Table 2-1. Employment by Department - Brush         
  Wellman, Inc., Elmore, OH (1999)**                    
  ----------------------------------------------------- -----------------
  **Plant Department**                                  **No. of
                                                        Workers**

  Accounting                                            16

  Alloy R&D                                             12

  Be Machinists                                         28

  Be Powder                                             4

  Billet Prep                                           22

  Boiler Operators                                      7

  Bulk Products                                         79

  Decontamination                                       7

  Environmental Health & Safety Management              4

  Electrical Maintenance                                24

  Engineering                                           13

  Environmental Health & Safety                         10

  Extrusion                                             16

  Furnace Build                                         14

  GC Salt                                               3

  Information Services                                  4

  Janitors                                              9

  Lab                                                   21

  Landfill                                              48

  Laundry                                               9

  Maintenance                                           47

  Medical Dept                                          20

  Melting & Casting                                     45

  Mix Makeup                                            4

  Mold & Tool                                           3

  New Cast Shop                                         22

  New Strip Operations                                  23

  Outside Maintenance                                   7

  Pebble/Oxide Plant                                    24

  Personnel                                             19

  Powdered Metal                                        4

  Preventive Maintenance                                8

  Primary Operations                                    27

  Process Engineering                                   5

  Production Control                                    15

  Purchasing                                            11

  QC/QA                                                 39

  Recycled Materials                                    2

  Resource Recovery                                     16

  Sales                                                 12

  Shipping & Receiving                                  19

  Special Products                                      12

  Store Room                                            7

  Strip Operations                                      47

  Technical Maintenance                                 7

  Vacuum Casting                                        8

  Vehicle Maintenance                                   3

  Waste Water Treatment                                 4

  Whiting Arc Furnace                                   14

  **Total**                                             824

  Source: Employment data supplied by Michael A.        
  McCawley, Ph.D. (McCawley Consulting, Morgantown,     
  West Virginia).                                       
  -----------------------------------------------------------------------

NIOSH data indicate that measurable beryllium exposures routinely occur
in Alloy R&D, Pebble/Oxide Plant, Powdered Metal Products and the
Resource Recovery departments (Maintenance being an exception, since the
exposure occurs not in the department but when workers from the
department work in the other parts of the plant.) (McCawley, 2000). The
chemical form of beryllium to be expected varies between those
departments. In Alloy, the beryllium is likely to be found as
beryllium-copper (BeCu), beryllium-nickel (BeNi) and beryllium-aluminum
(BeAl) alloys. Additionally, beryllium oxide (BeO) is likely to be found
in Alloy "hot work" applications (melting and casting, hot rolling,
annealing and extrusion) resulting from the formation of metal oxides
during processing. In the Pebble/Oxide Plant, the beryllium should be in
the forms of beryllium oxide, ammonium beryllium fluoride, beryllium
fluoride, and beryllium. In Powdered Metal Products, the form is
beryllium alone, and in Resource Recovery it may be any of the forms
mentioned above.

**2.2 OVERVIEW OF PROCESS TECHNOLOGY**

1.  **Metallic Beryllium Production**

**Beryllium Pebble Production:** Beryllium pebbles are produced from
beryllium hydroxide. The beryllium hydroxide is a product of the mining
and milling process that has taken place in Delta, UT. The first three
steps in metallic beryllium production at the Brush Wellman Elmore
facility occur in the chemical plant (Figure 2.1, See Appendix 2). In
these steps, beryllium hydroxide is converted to ammonium beryllium
fluoride (ABF). The ABF is purified through a series of precipitations
and filtrations. The purified crystals of ABF are next decomposed to
beryllium fluoride (BeF~2~) in the fluoride furnace. The beryllium
fluoride is further reduced in the presence of magnesium in the
reduction furnace at approximately 900° C to produce beryllium pebbles.
The beryllium pebbles are then separated from the magnesium fluoride in
a hammer mill. The end result is a 98 percent pure beryllium pebble
product (National Materials Advisory Board, 1989).

The wet chemical processes are thought to have a lower risk of aerosol
generation. However, spills and splashing may have contributed to
inadvertent skin exposure and contaminated clothing and shoes. The
fluoride furnace and reduction furnace areas, on the other hand, were
recognized as problem areas (Kreiss et al, 1997).

**Vacuum Casting:** Beryllium pebbles and other high-grade beryllium
scrap (e.g. machining chips) are charged into a vacuum melting furnace.
The vacuum melted beryllium metal is poured into a graphite mold to
produce a 400-lb vacuum cast billet.

**Powder Manufacturing:** Vacuum cast beryllium billets are machined
into chips on lathes with multiple machining cutters. The chips are then
processed in one of four powder producing operations: attrition mill,
impact grinding mill, ball mill, or atomization.

**Powder Consolidation:** Beryllium powder is consolidated with vacuum
hot pressing or near-net-shape (NNS) technologies. In vacuum hot
pressing, beryllium powder is loaded into a graphite die; the powder
inside the die is subjected to temperatures up to 1125°C and pressures
up to 1200 psi to produce vacuum hot pressed billets of varying
dimensions. Near-net-shape powder consolidation techniques are also
employed in the form of hot isostatic pressing and cold isostatic
pressing. In hot isostatic pressing, NNS beryllium parts are produced by
loading beryllium powder into a welded mild steel container shaped and
sized to account for the shrinkage that occurs after hot isostatic
pressing. The container is sealed and vacuum outgassed to remove
residual gas inside the container. The container is loaded into an
isostatic press where it is subjected to temperature and pressure to
consolidate the powder into a part; size and shape determined by the
container volume. The mild steel container is removed by chemically
dissolving the steel in a nitric acid bath. Cold isostatic pressing is
similar to hot in that beryllium powder is loaded into a die (usually
rubber); the die is sealed and outgassed; cold pressed and the rubber
mold is mechanically removed. The near-net-shaped parts can then be
further machined to some final form. Near-net-shaped parts are generally
sent out for final machining at a precision machine shop.

**Machining**: The hot vacuum pressed billets are machined using typical
metal fabrication techniques (e.g., lathe turning, milling, band sawing,
surface grinding, etc.) in the machine shop.

> **2.2.2 Beryllium Alloy Production**

**Master Alloy Production:** In the first step of beryllium alloy
production, beryllium hydroxide is calcined into beryllium oxide powder
and mixed with carbon/binders to form pellets that are transferred to a
charge bin. This is done through a computer-controlled closed system.
The charge bin holds approximately one ton of beryllium oxide pellets,
copper, and petroleum coke combined. These materials are used to charge
the Whiting Arc Furnace (Figure 2.2, See Appendix 2). The output from
the Whiting Arc Furnace is a 30-lb beryllium-copper "Master Alloy" pig
that has a beryllium content of 3.8 percent by weight. This product is
then used in casting the larger product billets, which are lower in
beryllium content. Dross from this and other operations can be recycled
into the furnace for reclamation.

#######  Melting and Casting Operations: The cast shop produces billets of beryllium-copper, beryllium-nickel and beryllium-aluminum up to 40 feet in length. Both an old and new cast shops are in operation at the Elmore Facility, located separately from each other. Round billets are processed in an extrusion press to make rods, bars, tubes and wire products. Rectangular billets are also processed to make strip and plate products as well as being sold directly to customers.

The new cast shop has an improved ventilation design and also limited
access to assure better control of beryllium dust migration. The thermal
load, due to the process and the extra burn protection on the workers in
this process, is such that continuous skin coverage for the entire shift
adds a noticeable burden.

**Scrap Furnace Operations:** The casting operation also includes scrap
furnace operations, in which scrap from the Brush Wellman Facility,
other operations at Elmore, the distribution centers, and from customers
is returned, re-melted and used. Scrap contaminated with rolling or
cutting oils is melted in the Scrap Melting Furnace (Figure 2.3, See
Appendix 2) in the old cast shop and cast into ingots. Clean scrap can
be introduced directly into the product heats.

**Billet Casting:** The large billets (up to several feet in diameter
and tens of feet long) are cast using a direct chill (DC) process
(Figure 2.4, See Appendix 2). A one to two feet deep, open-ended,
water-cooled mold is used in the process. Hydraulically controlled
tilting melting furnaces are used to pour the molten metal into a
tundish that transfers the molten metal to the water-cooled mold in a
vertical water-filled pit. As the metal is poured through the mold it
rapidly solidifies and retains the shape of the mold forming a billet.
Further cooling and solidification of the billet occurs in the pit.
Either rectangular or cylindrical molds can be produced depending on the
processing needs (i.e., strip and plate versus rod, bar, and tube).

**Homogenization:** Billets are reheated after casting in a process
similar to tempering. The reheating homogenizes the various materials
within the billet (Figure 2.5, See Appendix 2). This homogenization can
be done to the material at other stages in the manufacturing process as
well. The Reading facility regularly heats their products after rolling
or cutting is done.

######## **Billet Preparation:** Once the billets have been cast, they may be cut into multiple lengths or sectioned on a saw (Figure 2.6, See Appendix 2), be turned on a lathe (Figure 2.7, See Appendix 2) or have their surfaces conditioned on the scalping mill (Figure 2.8, See Appendix 2). For those billets that will become tubing, a deep hole-drilling machine (Figure 2.9, See Appendix 2) is used to bore holes before the billet is sent to extrusion.

**Rod, Bar, and Tube Products:** Both hot-worked and cold-drawn items
are manufactured from the billets. The hot-worked items are either
forged, or extruded to dimensionally form the product and refine the
cast grain structure. Solution annealing, flattening or straightening,
age hardening, cutting to size, surface cleaning, and inspection
operations are used. Shapes commonly manufactured are rods, bars, tubes,
rings and some special cross-sectional shapes, all in a wide range of
sizes.

The cold-drawn products are manufactured when the application requires
closer dimensional tolerance, more refined metallurgical properties,
more stringent physical or mechanical property ranges, or better surface
finish than the less costly hot-worked products. The additional
processing can be as simple as adding a pointing and drawing operation,
but could also include additional annealing and cleaning steps or other
metallurgical, dimensional, and quality assurance tests.

**Extrusion:** The extrusion press (Figure 2.10, See Appendix 2) refines
the cast structure by pushing a round cast billet through a die,
producing a semi-finished hot-worked product. Rods, bars, and tubes of
many dimensions can be produced this way. An abrasive cut-off saw is
used to cut the product at the exit end of the extrusion press die.
Additionally, a hot coiler is attached to the system to produce wire up
to 1.25 inches in diameter. Water spray nozzles along the length of the
runout and walking beam tables are used to provide uniform cooling and
keep the materials straight. Some products are cut to length on an
abrasive cut-off saw at the end of the runout table. The extrusion
process is located adjacent to the billet preparation area and not in
the Rod, Bar and Tube Mill.

**Annealing:** The Sauder Furnace Complex (Figure 2.11, See Appendix 2)
ages and anneals the rod, bar, and tube products. Annealing is a process
in which the alloy is heated and then cooled very slowly and uniformly.
The time and temperature of the process are set according to the
properties desired. Annealing increases ductility and lessens the
possibility of a failure in service by reducing internal strain.

**Swager:** Before cold drawing, rods or tubes must be made smaller on
one end in order to feed material through the drawing die to the jaw
grips. Additionally, the smaller end must be strengthened to prevent
breaking during drawing. A swager (Figure 2.12, See Appendix 2) is used
to cold point all rod and tube products prior to drawing. At the swager,
material is fed into four tapered dies that hammer the work piece over a
three-inch length. An eight-inch point length is required before
drawing.

**Bulk Pickling:** The bulk pickler (Figure 2.13, See Appendix 2) is
used to clean rod, bar, tube, and wire products that have either been
cut to length or are in coil form. The operation consists of three
steps:

-   A sodium hydroxide (NaOH) bath for 30 minutes

-   A nitric acid bath for 5 minutes or less

-   Dipping in stain/oxidation inhibitor (benzotriazole or BTA)

The acid content, bath temperature, copper content, and urea content are
computer controlled to maintain optimal surface cleanliness and minimize
fuming.

**Drawing:** After annealing, bulk pickling and pointing, rods and tubes
are drawn (pulled) through a die to produce a wide variety of shapes and
sizes. The Lombard drawbench (Figure 2.14, See Appendix 2) utilizes a
hydraulic ram to provide the force necessary to achieve the required
product reduction. Products finished by this process have very smooth
surfaces and are straight within the required tolerance. The product can
be further heat treated or subjected to rotary straightening for
improved straightness and finish.

**Degreasing and Cutting:** The Phillips degreaser (Figure 2.15, See
Appendix 2) uses perchloroethylene in liquid and vapor form. The
material is degreased after drawing to remove the drawing lubricant
prior to straightening and age hardening. The Marvel band saw (Figure
2.16, See Appendix 2) is used to cut rod and tube to specific lengths.
The saw gives a square cut for tight tolerances.

**Straightening:** The straightening process requires that a material be
flexed slightly beyond its elastic limit in both tension and
compression. In rotary straightening (Figure 2.17, See Appendix 2), two
specially contoured rolls inclined at opposing angles cause the round
product to rotate while pressure is applied. Bump straightening (Figures
2.18 and 2.19, See Appendix 2) uses pressure from a ram to deflect the
piece as it is supported at its ends by anvils on the carriage.

**Wire Rolling:** Two tandem wire mills (Figure 2.20, See Appendix 2)
are used for the initial cold working process. The strands of grooved
rolls are alternately opposed to improve the uniformity of the work. The
shaped grooves are progressively reduced in size to provide the desired
reduction as the wire passes through the mill. Coiled wire from the
tandem mills is supplied at various gauges of 0.125 inches and over.

With the exception of extrusion, these operations are mirrored in the
Reading plant. The Reading plant produces multiple dimensions of rod,
bar, and tube to customer specification, while the Elmore plant
primarily produces a limited variety of dimensions and length, much of
which is shipped to the Reading plant.

**Strip Operations:** Sheets of alloy strip are produced from castings
from the induction furnace and are rolled from billets into single coils
on the hot mill. There are two hot mills in operation at the Elmore
plant; a smaller size old hot mill and the new, larger hot mill. Smaller
coils from the old hot mill are welded together to produce full-length
coils weighing approximately 8,000 pounds. The new hot mill produces
larger coils and the intermediate coil-welding step is not required. The
coils are then milled, dimensioned, and cut to specification and length.
With the exception of hot rolling and slab milling, these operations are
mirrored in the Reading plant. The Reading plant produces multiple
dimensions of strip to customer specification, while the Elmore plant
primarily produces a limited variety of dimensions and length, much of
which is shipped to the Reading plant.

**Roller Hearth Furnace:** Large coils of alloy are continuously
solution-annealed in the roller hearth furnace in order to soften them
for further cold rolling. The roller hearth furnace (Figure 2.21, See
Appendix 2) has heating zones in which the strip is heated to
re-crystallize the microstructure and re-dissolve the beryllium-copper
compounds present after the rolling process. After cold rolling, the
strip is annealed again in the furnace.

**Slab Milling Machine:** The function of the slab milling machine
(Figure 2.22, See Appendix 2) is to remove scale, defects, and
undesirable metal phases from the surface of the strip of various alloys
before further processing. To do this, the strip is fed through the slab
milling machine, where the cutter mills one surface at a time. The depth
of the cut is determined by an adjustable pinch roll controlled by the
operator.

**Light-Gauge** **Weld Line:** After the material has been processed
through the roller hearth furnace, slab milled, and cold rolled on the
four-high mill, coils are sent to the light-gauge weld line (Figure
2.23, See Appendix 2) for slitting of edges to eliminate edge cracks and
provide a uniform width.

**Strand and Light-Gauge Strip Pickle Lines:** The role of the pickle
line (Figure 2.24, See Appendix 2) is to chemically remove oxidation
formed on the strip during annealing. Sodium hydroxide is used to remove
the oils and condition the oxidized surface for pickling. Nitric acid is
then used to remove oxide scale and produce a bright surface. There is
also a light-gauge strip pickle line that functions in a similar manner.

**Sendzimir Mill (Z-Mill):** The Z-Mill is a 20-roll cluster, reversing
cold rolling mill (Figure 2.25, See Appendix 2). It is designed for
precision rolling to thin gauges with the strip held in high tension by
the winders.

**Light-Gauge Slitter:** The light-gauge slitter line (Figure 2.26, See
Appendix 2) is used for edge trimming to remove small edge cracks after
cold rolling. It is also capable of multiple slit strip widths to
increase versatility for meeting customer requirements.

**Light-Gauge Strip Annealing:** The light-gauge strip annealing line
(Figure 2.27, See Appendix 2) performs the same task as other annealers
noted above. A protective nitrogen atmosphere is used in the heating
zone to reduce oxidation. Quenching is also done with a recirculating
protective atmosphere.

**Plate Leveling:** The roller levelers (Figures 2.28 and 2.29, See
Appendix 2) are used to flatten alloy plate products. The actual
flattening or leveling process is performed by bending the material past
its elastic limit while it passes over the roller. The amount of bending
can be controlled by adjusting the bottom rolls up or down. During the
operation, unleveled plate is fed into the pinch rolls and is formed
into a uniformly bent shape. While still in the machine, the roll is
reversed and final leveling is accomplished. The process can be repeated
if necessary.

**Plate Sawing:** Plates at intermediate, ready to finish, or finished
gauges are sawed to size or for metallurgical samples (Figure 2.30, See
Appendix 2). Side trimming can be performed on pieces up to 12 feet in
length.

**Electroplating:** The electroplating line (Figure 2.31, See Appendix
2) is used to plate nickel onto alloy finished rolled strip obtained
from the Reading plant. This product can later be gold-plated by
customers during the manufacture of electrical connectors. The strip is
first subjected to a sodium hydroxide treatment followed by pickling in
a sulfuric acid/hydrogen peroxide solution. Nickel is then plated on
both sides of the strip product.

**2.2.3 Other Operations**

The Elmore plant has its own analytical laboratories for both
metallurgical and environmental analyses. Lab technicians visit the
operations described above. There are also maintenance and janitorial
staff as well as a small laundry staff to care for the company-provided
clothes, which are kept on site and into which workers must change in
and out each day. Medical staff also are on site and may be out on the
plant floor at times.

Engineering and administrative staffs are located in two buildings,
which, in the past, were open to foot traffic from the plant. These are
the east and west administrative buildings. Only the west administrative
building remains open to foot traffic from the plant and workers in that
building must abide by the same clothing protection as the plant
workers.

**2.2.4 Number range CHAPTERBeryllium Oxide Production**

Beryllium oxide is made from the beryllium hydroxide produced at the
Delta, UT extraction facility. Several grades of beryllium oxide powders
are formulated---ceramic grade and high purity beryllium oxide
powders---using the following processes:

-   *Primary extraction*. In the primary production process, beryllium
    hydroxide is dissolved in sulfuric acid. This solution is then
    filtered to remove insoluble oxide and sulfate impurities. The
    resulting clear filtrate is allowed to evaporate and become
    concentrated producing high-purity beryllium sulfate upon cooling.

-   *Calcination*. The beryllium sulfate salt is then calcined in a
    hearth furnace at carefully controlled temperatures between 1,150
    degrees C and 1,450 degrees C. The temperatures are selected to
    create specific properties of the beryllium oxide powders as
    required by individual beryllium oxide ceramic fabricators.
    Commercial beryllium oxide powder, calcined at 1,150 degrees C,
    consists of crystallites ranging from about 0.1 to 0.2 m in size.
    Powder particles are made up of larger clusters or aggregates of the
    smaller crystallites.

-   *Chelating*. Ceramic-grade beryllium oxide is manufactured by adding
    organic chelating agents to the filtered beryllium sulfate solution
    and then precipitating out beryllium hydroxide using ammonium
    hydroxide powder.

-   *Gas atomization*. This process converts beryllium oxide powder
    crystals into smaller, isotropic spherical beryllium powders used
    for metal matrix composites.

-   *Packaging*. Powdered beryllium oxide is packaged in drums for
    shipment directly to customers as well as to Brush Wellman's Tucson
    plant.

# SECTION 3

**EXPOSURE PROFILE AND TECHNOLOGICAL**

**FEASIBILITY ANALYSIS**

The exposure profile for beryllium production at Brush Wellman's Elmore,
Ohio facility includes nearly all employees and incorporates the
production of pure beryllium, beryllium oxide, and beryllium alloys.
Individual full-shift personal breathing zone (lapel-type) exposure
levels were obtained from Brush Wellman for the exposure profile. These
data represent baseline exposure monitoring conducted by Brush Wellman
in 1999 and are summarized in the OSHA beryllium docket (OSHA Docket
H005C, Exhibit 6-9-5-3). Samples were analyzed by NIOSH Methods 7102
(Beryllium and compounds, as Be) or 7300 (Elements by ICP) and the
analytical limit of detection was reported to be 0.1 micrograms per
filter. For sample results less than the limit of detection, a sample
weight of 0.05 micrograms (one half the limit of detection) was used to
calculate the volume adjusted non-detectable sample concentrations
(Kent, 2005).

Job titles listed in the Brush Wellman exposure database were reviewed
with industry experts to obtain information regarding work tasks,
sources of beryllium exposure, existing exposure controls, and potential
additional exposure controls. ERG then broadly categorized each job
title into one of eight job categories based on the type of work
employees perform. Each job category contains work groups that more
specifically identify employee job functions. The eight job categories
utilized in the exposure profile include administrative, site support,
production support, cold work, hot work, powdering, chemical operations,
and furnace operations. The work groups contained within each job
category are presented in Table 3-1. After each job title was
categorized, individual exposure levels for these job titles were coded,
sorted, and statistically evaluated by job category and work group.

+------------------+---------------------------------------------------+
| **Table 3-1. Job |                                                   |
| Categories and   |                                                   |
| Work Groups for  |                                                   |
| Brush Wellman,   |                                                   |
| Inc., Elmore,    |                                                   |
| Ohio**           |                                                   |
|                  |                                                   |
| **(NAICCS        |                                                   |
| 331419)**        |                                                   |
+==================+===================================================+
| **Job Category** | **Work Groups**                                   |
+------------------+---------------------------------------------------+
| Administrative   | Operations/Management                             |
|                  |                                                   |
|                  | Human Resources                                   |
|                  |                                                   |
|                  | Information Systems                               |
|                  |                                                   |
|                  | Credit Union                                      |
|                  |                                                   |
|                  | Environmental Health and Safety                   |
|                  |                                                   |
|                  | Medical                                           |
|                  |                                                   |
|                  | Training                                          |
|                  |                                                   |
|                  | Production Planning                               |
|                  |                                                   |
|                  | Engineering                                       |
+------------------+---------------------------------------------------+
| Site Support     | Laundry (work clothing and respirators)           |
|                  |                                                   |
|                  | Janitorial                                        |
|                  |                                                   |
|                  | Landfill                                          |
|                  |                                                   |
|                  | Facility Maintenance                              |
|                  |                                                   |
|                  | Analytical Laboratories                           |
|                  |                                                   |
|                  | Shipping/Receiving/Material Handling              |
|                  |                                                   |
|                  | Wastewater Treatment                              |
|                  |                                                   |
|                  | Store (supply) Rooms                              |
|                  |                                                   |
|                  | Security                                          |
|                  |                                                   |
|                  | Boiler                                            |
|                  |                                                   |
|                  | Facility Engineering                              |
|                  |                                                   |
|                  | Cafeteria                                         |
|                  |                                                   |
|                  | Decontamination                                   |
+------------------+---------------------------------------------------+
| Production       | Scrap Recycling\* (beryllium and copper)          |
| Support          |                                                   |
|                  | Maintenance (production equipment; furnaces and   |
|                  | tools; molds and dies)                            |
|                  |                                                   |
|                  | Research and Development                          |
|                  |                                                   |
|                  | Quality Assurance (QA)/Quality Control            |
|                  | (QC)/Inspection                                   |
+------------------+---------------------------------------------------+
| Cold Work        | Rolling                                           |
|                  |                                                   |
|                  | Straightening                                     |
|                  |                                                   |
|                  | Drawing                                           |
|                  |                                                   |
|                  | Machining (alloy, high beryllium, and billet      |
|                  | preparation)                                      |
|                  |                                                   |
|                  | Mix Makeup (furnace charge material)              |
+------------------+---------------------------------------------------+
| Hot Work         | Hot Rolling and Extrusion                         |
|                  |                                                   |
|                  | Annealing                                         |
|                  |                                                   |
|                  | Welding                                           |
|                  |                                                   |
|                  | Pickling (elevated bath temperatures)             |
|                  |                                                   |
|                  | Degreasing (elevated solvent temperature)         |
+------------------+---------------------------------------------------+
| Powdering        | Impact Grinding (powder making operation for      |
|                  | compact loading/sintering);                       |
|                  |                                                   |
|                  | Compact Loading/Sintering (powder-loaded dies are |
|                  | sintered in furnaces to form billets);            |
|                  |                                                   |
|                  | Near-Net-Shape (powder is loaded into dies and    |
|                  | consolidated into preformed shapes using          |
|                  | isostatic pressing)                               |
+------------------+---------------------------------------------------+
| Chemical         | Beryllium Sulfate Salt Manufacture and Wet        |
| Operations       | Screening (GC salt and wet screening operators)   |
+------------------+---------------------------------------------------+
| Furnace          | Alloy Induction and Arc Furnaces                  |
| Operations       |                                                   |
|                  | High Beryllium Vacuum Cast and Atomization        |
|                  | Furnaces                                          |
|                  |                                                   |
|                  | Beryllium Oxide Furnaces                          |
+------------------+---------------------------------------------------+
| \* Includes the  |                                                   |
| following Brush  |                                                   |
| Wellman          |                                                   |
| operations:      |                                                   |
| inventory        |                                                   |
| control center   |                                                   |
| (ICC); scrap     |                                                   |
| reclamation;     |                                                   |
| leaching; and    |                                                   |
| resource         |                                                   |
| recovery.        |                                                   |
+------------------+---------------------------------------------------+

In addition to the 1999 Brush Wellman exposure database, ERG also
reviewed unpublished exposure data from OSHA's Integrated Management
Information System (IMIS) for beryllium. These data, however, are
difficult to interpret because information regarding worker activities,
workplace conditions, engineering controls, personal protective
equipment, non-detectable sample concentrations, and sample duration is
not available (i.e., positive sample results may represent less than
full-shift exposure). Additionally, when attempting to identify
establishments in the database with potential beryllium exposure, it is
not possible to determine whether beryllium was included in the sample
analysis request because there is known potential workplace exposure to
beryllium or because it was part of a routine metal screening.

The IMIS database contains 150 positive personal samples for the
beryllium production sector. Sample dates range from April 1, 1980
through November 1, 2000; however, 91 percent of the positive samples
were collected during 1993. The median exposure level is 0.69 μg/m^3^
with a mean of 3.1 μg/m^3^ and a range from 0.04 μg/m^3^ to 99 μg/m^3^.
The job titles associated with the highest and lowest exposures are
furnace operator and loader operator, respectively. Fifty-seven of the
positive levels are associated with unspecified operators; 42 of the
positive levels are associated with furnace operations; 35 of the
positive levels are associated with miscellaneous job titles; nine of
the positive levels are associated with Brush Wellman's pebbles plant
operation (which was recently decommissioned); and seven of the positive
levels are associated with machining activities.

Tables 3-2 and 3-3 represent the exposure profile for workers at Brush
Wellman's Elmore, Ohio facility. These tables summarize *all* of the
available full-shift PBZ (lapel-type) total beryllium exposure profile
data and report the distribution of these results in relation to PEL
options. Although all of the available full-shift PBZ total beryllium
exposure results are presented, the technological feasibility analysis
for a proposed beryllium standard does not address all job
categories/work groups because exposure controls will not be required
for workers with median exposures less than 0.1 μg/m^3^ (the lowest
proposed PEL option). Therefore discussion regarding affected
occupations is primarily limited to those work groups with median
exposures greater than or equal to 0.1 μg/m^3^. For each of these work
groups, a brief process overview is provided along with available
information regarding potential sources of exposure, and existing and
possible additional controls. Most of the commentary provided is based
on telephone discussions with industry consultants and representatives.
To a very limited extent, the discussion is supplemented with
information obtained from published documents and observations made by
ERG during a tour of the Brush Wellman Elmore facility on August 30 --
31, 2004. In general, no information is available to explain the
elevated maximum exposure levels reported for a substantial number of
work groups.

+----------------------------------+------+-----------+-------+------+
| **Table 3-2. Summary of 1999     |      |           |       |      |
| Full-Shift^a^ PBZ Total          |      |           |       |      |
| Beryllium Exposure Levels^b^ for |      |           |       |      |
| Workers at Brush Wellman, Inc.,  |      |           |       |      |
| Elmore, Ohio (NAICCS 331419)**   |      |           |       |      |
+==================================+======+===========+=======+======+
| **Job Category and**             | *    | **Range   | **M   | **   |
|                                  | *No. | (μ        | ean** | Medi |
| **Work Group**                   | of** | g/m^3^)** |       | an** |
|                                  |      |           | **(   |      |
|                                  | **S  |           | μg/m^ | *    |
|                                  | ampl |           | 3^)** | *(μg |
|                                  | es** |           |       | /m^3 |
|                                  |      |           |       | ^)** |
+----------------------------------+------+-----------+-------+------+
| **ADMINISTRATIVE**               | **9  | **0.05 to | **0   | **0. |
|                                  | 81** | 4.54**    | .10** | 05** |
+----------------------------------+------+-----------+-------+------+
| Operations/Management            | 440  | 0.05 to   | 0.09  | 0.05 |
|                                  |      | 2.68      |       |      |
+----------------------------------+------+-----------+-------+------+
| Human Resources                  | 48   | 0.05 to   | 0.05  | 0.05 |
|                                  |      | 0.05      |       |      |
+----------------------------------+------+-----------+-------+------+
| Information Systems              | 45   | 0.05 to   | 0.05  | 0.05 |
|                                  |      | 0.10      |       |      |
+----------------------------------+------+-----------+-------+------+
| Credit Union                     | 15   | 0.05 to   | 0.05  | 0.05 |
|                                  |      | 0.10      |       |      |
+----------------------------------+------+-----------+-------+------+
| Environmental Health and Safety  | 132  | 0.05 to   | 0.07  | 0.05 |
|                                  |      | 1.88      |       |      |
+----------------------------------+------+-----------+-------+------+
| Medical                          | 52   | 0.05 to   | 0.06  | 0.05 |
|                                  |      | 0.17      |       |      |
+----------------------------------+------+-----------+-------+------+
| Training                         | 15   | 0.05 to   | 0.07  | 0.05 |
|                                  |      | 0.34      |       |      |
+----------------------------------+------+-----------+-------+------+
| Production Planning              | 134  | 0.05 to   | 0.16  | 0.05 |
|                                  |      | 4.54      |       |      |
+----------------------------------+------+-----------+-------+------+
| Engineering                      | 100  | 0.05 to   | 0.13  | 0.07 |
|                                  |      | 1.98      |       |      |
+----------------------------------+------+-----------+-------+------+
| **SITE SUPPORT**                 | **8  | **0.05 to | **0   | **0. |
|                                  | 79** | 4.22**    | .11** | 05** |
+----------------------------------+------+-----------+-------+------+
| Laundry (work clothing and       | 48   | 0.05 to   | 0.07  | 0.05 |
| respirators)                     |      | 0.49      |       |      |
+----------------------------------+------+-----------+-------+------+
| Janitorial                       | 65   | 0.05 to   | 0.09  | 0.07 |
|                                  |      | 0.65      |       |      |
+----------------------------------+------+-----------+-------+------+
| Landfill                         | 30   | 0.05 to   | 0.05  | 0.05 |
|                                  |      | 0.11      |       |      |
+----------------------------------+------+-----------+-------+------+
| Facility Maintenance             | 130  | 0.05 to   | 0.11  | 0.07 |
|                                  |      | 1.23      |       |      |
+----------------------------------+------+-----------+-------+------+
| Analytical Laboratories          | 167  | 0.05 to   | 0.08  | 0.05 |
|                                  |      | 1.52      |       |      |
+----------------------------------+------+-----------+-------+------+
| Shipping/Receiving/Material      | 132  | 0.05 to   | 0.06  | 0.05 |
| Handling                         |      | 0.19      |       |      |
+----------------------------------+------+-----------+-------+------+
| Wastewater Treatment             | 46   | 0.05 to   | 0.17  | 0.09 |
|                                  |      | 0.99      |       |      |
+----------------------------------+------+-----------+-------+------+
| Store (supply) Rooms             | 32   | 0.05 to   | 0.06  | 0.05 |
|                                  |      | 0.15      |       |      |
+----------------------------------+------+-----------+-------+------+
| Security                         | 31   | 0.05 to   | 0.07  | 0.05 |
|                                  |      | 0.22      |       |      |
+----------------------------------+------+-----------+-------+------+
| Boiler Operators                 | 18   | 0.05 to   | 0.23  | 0.16 |
|                                  |      | 0.48      |       |      |
+----------------------------------+------+-----------+-------+------+
| Facility Engineering             | 116  | 0.05 to   | 0.08  | 0.05 |
|                                  |      | 1.13      |       |      |
+----------------------------------+------+-----------+-------+------+
| Cafeteria                        | 16   | 0.05 to   | 0.07  | 0.06 |
|                                  |      | 0.17      |       |      |
+----------------------------------+------+-----------+-------+------+
| Decontamination                  | 48   | 0.05 to   | 0.47  | 0.18 |
|                                  |      | 4.22      |       |      |
+----------------------------------+------+-----------+-------+------+
| **PRODUCTION SUPPORT**           | **8  | **0.02 to | **0   | **0. |
|                                  | 10** | 22.71**   | .52** | 08** |
+----------------------------------+------+-----------+-------+------+
| Scrap Recycling                  | 111  | 0.05 to   | 1.08  | 0.31 |
|                                  |      | 16.38     |       |      |
+----------------------------------+------+-----------+-------+------+
| *Inventory Control Center*       | 16   | 0.08 to   | 0.36  | 0.17 |
|                                  |      | 2.66      |       |      |
+----------------------------------+------+-----------+-------+------+
| *Scrap Reclamation*              | 26   | 0.05 to   | 1.22  | 0.43 |
|                                  |      | 8.89      |       |      |
+----------------------------------+------+-----------+-------+------+
| *Leaching*                       | 6    | 0.05 to   | 3.39  | 0.44 |
|                                  |      | 16.38     |       |      |
+----------------------------------+------+-----------+-------+------+
| *Resource Recovery*              | 63   | 0.05 to   | 0.98  | 0.30 |
|                                  |      | 6.75      |       |      |
+----------------------------------+------+-----------+-------+------+
| Maintenance                      | 345  | 0.02 to   | 0.73  | 0.12 |
|                                  |      | 22.71     |       |      |
+----------------------------------+------+-----------+-------+------+
| *Production Equipment*           | 232  | 0.05 to   | 0.61  | 0.11 |
|                                  |      | 22.71     |       |      |
+----------------------------------+------+-----------+-------+------+
| *Furnaces and Tools*             | 58   | 0.05 to   | 1.73  | 0.53 |
|                                  |      | 14.62     |       |      |
+----------------------------------+------+-----------+-------+------+
| *Molds and Dies*                 | 55   | 0.02 to   | 0.19  | 0.05 |
|                                  |      | 2.98      |       |      |
+----------------------------------+------+-----------+-------+------+
| Research and Development         | 119  | 0.05 to   | 0.11  | 0.05 |
|                                  |      | 2.01      |       |      |
+----------------------------------+------+-----------+-------+------+
| QA/QC/Inspection                 | 235  | 0.05 to   | 0.14  | 0.05 |
|                                  |      | 13.72     |       |      |
+----------------------------------+------+-----------+-------+------+
| **COLD WORK**                    | **6  | **0.04 to | **0   | **0. |
|                                  | 06** | 24.89**   | .32** | 08** |
+----------------------------------+------+-----------+-------+------+
| Rolling                          | 30   | 0.05 to   | 0.13  | 0.05 |
|                                  |      | 1.08      |       |      |
+----------------------------------+------+-----------+-------+------+
| Straightening                    | 56   | 0.05 to   | 0.17  | 0.06 |
|                                  |      | 1.83      |       |      |
+----------------------------------+------+-----------+-------+------+
| Drawing                          | 31   | 0.05 to   | 0.07  | 0.05 |
|                                  |      | 0.20      |       |      |
+----------------------------------+------+-----------+-------+------+
| Mix Make-up (furnace charge      | 51   | 0.05 to   | 0.46  | 0.24 |
| material)                        |      | 4.20      |       |      |
+----------------------------------+------+-----------+-------+------+
| Machining                        | 438  | 0.04 to   | 0.36  | 0.09 |
|                                  |      | 24.89     |       |      |
+----------------------------------+------+-----------+-------+------+
| *Billet Preparation*             | 90   | 0.05 to   | 0.46  | 0.13 |
|                                  |      | 18.97     |       |      |
+----------------------------------+------+-----------+-------+------+
| *Alloys*                         | 216  | 0.04 to   | 0.19  | 0.06 |
|                                  |      | 16.00     |       |      |
+----------------------------------+------+-----------+-------+------+
| *High Beryllium*                 | 132  | 0.05 to   | 0.56  | 0.17 |
|                                  |      | 24.89     |       |      |
+----------------------------------+------+-----------+-------+------+
| **HOT WORK**                     | **2  | **0.01 to | **0   | **0. |
|                                  | 97** | 2.21**    | .12** | 06** |
+----------------------------------+------+-----------+-------+------+
| Hot Rolling/Extrusion            | 150  | 0.01 to   | 0.09  | 0.06 |
|                                  |      | 0.56      |       |      |
+----------------------------------+------+-----------+-------+------+
| Annealing                        | 64   | 0.05 to   | 0.13  | 0.08 |
|                                  |      | 0.52      |       |      |
+----------------------------------+------+-----------+-------+------+
| Welding                          | 15   | 0.15 to   | 0.52  | 0.33 |
|                                  |      | 2.21      |       |      |
+----------------------------------+------+-----------+-------+------+
| Pickling (elevated bath          | 47   | 0.05 to   | 0.08  | 0.05 |
| temperatures)                    |      | 0.31      |       |      |
+----------------------------------+------+-----------+-------+------+
| Degreasing (elevated solvent     | 21   | 0.05 to   | 0.07  | 0.05 |
| temperature)                     |      | 0.21      |       |      |
+----------------------------------+------+-----------+-------+------+
| **POWDERING**                    | **   | **0.06 to | **0   | **0. |
|                                  | 72** | 11.52**   | .82** | 37** |
+----------------------------------+------+-----------+-------+------+
| Operator/Impact Grinding         | 26   | 0.08 to   | 0.79  | 0.59 |
|                                  |      | 3.33      |       |      |
+----------------------------------+------+-----------+-------+------+
| Compact Loading/Sintering        | 19   | 0.06 to   | 1.11  | 0.22 |
|                                  |      | 11.52     |       |      |
+----------------------------------+------+-----------+-------+------+
| Near Net Shape (operator and     | 27   | 0.14 to   | 0.65  | 0.41 |
| welder)                          |      | 5.89      |       |      |
+----------------------------------+------+-----------+-------+------+
| **CHEMICAL OPERATIONS**          | **   | **0.05 to | **1   | **0. |
|                                  | 20** | 9.64**    | .02** | 47** |
+----------------------------------+------+-----------+-------+------+
| Be Sulfate^c^ (GC salt & wet     | 20   | 0.05 to   | 1.02  | 0.47 |
| screening operators)             |      | 9.64      |       |      |
+----------------------------------+------+-----------+-------+------+
| **FURNACE OPERATIONS**           | **1  | **0.05 to | **3   | **0. |
|                                  | 72** | 254.23**  | .80** | 68** |
+----------------------------------+------+-----------+-------+------+
| Alloy Induction                  | 97   | 0.06 to   | 1.46  | 0.50 |
|                                  |      | 48.07     |       |      |
+----------------------------------+------+-----------+-------+------+
| Alloy Arc                        | 38   | 0.15 to   | 1.95  | 0.95 |
|                                  |      | 9.37      |       |      |
+----------------------------------+------+-----------+-------+------+
| High Beryllium Vacuum Casting    | 9    | 0.13 to   | 1.05  | 0.31 |
|                                  |      | 4.03      |       |      |
+----------------------------------+------+-----------+-------+------+
| High Beryllium Atomization       | 13   | 0.54 to   | 31.67 | 5.56 |
|                                  |      | 254.23    |       |      |
+----------------------------------+------+-----------+-------+------+
| Beryllium Oxide                  | 15   | 0.05 to   | 1.07  | 0.27 |
|                                  |      | 5.13      |       |      |
+----------------------------------+------+-----------+-------+------+
| ^a^ Full-shift sample results    |      |           |       |      |
| are based on the actual sample   |      |           |       |      |
| duration. Full-shift means a     |      |           |       |      |
| sample duration of 360 minutes   |      |           |       |      |
| or longer.                       |      |           |       |      |
|                                  |      |           |       |      |
| ^b^Non-detected results are      |      |           |       |      |
| reported at one-half the         |      |           |       |      |
| analytical limit of detection.   |      |           |       |      |
|                                  |      |           |       |      |
| ^c^Be Sulfate means beryllium    |      |           |       |      |
| sulfate salt production.         |      |           |       |      |
|                                  |      |           |       |      |
| Source: Brush Wellman, 2004      |      |           |       |      |
+----------------------------------+------+-----------+-------+------+

+----------------------+-----+-----+-----+-----+-----+-----+------+
| **Table 3-3.         |     |     |     |     |     |     |      |
| Distribution of 1999 |     |     |     |     |     |     |      |
| Full-Shift^a^ PBZ    |     |     |     |     |     |     |      |
| Total Beryllium      |     |     |     |     |     |     |      |
| Exposure Levels^b^   |     |     |     |     |     |     |      |
| for Workers at Brush |     |     |     |     |     |     |      |
| Wellman, Inc.,       |     |     |     |     |     |     |      |
| Elmore, Ohio (NAICCS |     |     |     |     |     |     |      |
| 331419)**            |     |     |     |     |     |     |      |
+======================+=====+=====+=====+=====+=====+=====+======+
| **Job Category and** | **  |     |     |     |     |     | *    |
|                      | Num |     |     |     |     |     | *Tot |
| **Work Group**       | ber |     |     |     |     |     | al** |
|                      | of  |     |     |     |     |     |      |
|                      | R   |     |     |     |     |     |      |
|                      | esu |     |     |     |     |     |      |
|                      | lts |     |     |     |     |     |      |
|                      | in  |     |     |     |     |     |      |
|                      | Ra  |     |     |     |     |     |      |
|                      | nge |     |     |     |     |     |      |
|                      | (µ  |     |     |     |     |     |      |
|                      | g/m |     |     |     |     |     |      |
|                      | ^3^ |     |     |     |     |     |      |
|                      | )** |     |     |     |     |     |      |
+----------------------+-----+-----+-----+-----+-----+-----+------+
|                      | ≤   | \>  | \>  | \>  | \>  | \>  |      |
|                      | 0.1 | 0.1 | 0.2 | 0.5 | 1.0 | 2.0 |      |
|                      |     | to  | to  | to  | to  |     |      |
|                      |     | ≤   | ≤   | ≤   | ≤   |     |      |
|                      |     | 0.2 | 0.5 | 1.0 | 2.0 |     |      |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| **ADMINISTRATIVE**   | *   | **9 | **3 | **1 | **  | **  | **9  |
|                      | *83 | 0** | 9** | 0** | 6** | 3** | 81** |
|                      | 3** |     |     |     |     |     |      |
|                      |     | **  | **  | **  | *   | *   | **   |
|                      | **( | (9% | (4% | (1% | *(0 | *(0 | (100 |
|                      | 85% | )** | )** | )** | .5% | .5% | %)** |
|                      | )** |     |     |     | )** | )** |      |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| O                    | 368 | 45  | 20  | 4   | 2   | 1   | 440  |
| perations/Management |     |     |     |     |     |     |      |
|                      | (8  | (1  | (4. | (   | (0. | (   | (1   |
|                      | 4%) | 0%) | 5%) | 1%) | 5%) | 0%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| Human Resources      | 48  | 0   | 0   | 0   | 0   | 0   | 48   |
|                      |     |     |     |     |     |     |      |
|                      | (10 | (   | (   | (   | (   | (   | (1   |
|                      | 0%) | 0%) | 0%) | 0%) | 0%) | 0%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| Information Systems  | 45  | 0   | 0   | 0   | 0   | 0   | 45   |
|                      |     |     |     |     |     |     |      |
|                      | (10 | (   | (   | (   | (   | (   | (1   |
|                      | 0%) | 0%) | 0%) | 0%) | 0%) | 0%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| Credit Union         | 15  | 0   | 0   | 0   | 0   | 0   | 15   |
|                      |     |     |     |     |     |     |      |
|                      | (10 | (   | (   | (   | (   | (   | (1   |
|                      | 0%) | 0%) | 0%) | 0%) | 0%) | 0%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| Environmental Health | 119 | 11  | 1   | 0   | 1   | 0   | 132  |
| & Safety             |     |     |     |     |     |     |      |
|                      | (9  | (   | (   | (   | (   | (   | (1   |
|                      | 0%) | 8%) | 1%) | 0%) | 1%) | 0%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| Medical              | 48  | 4   | 0   | 0   | 0   | 0   | 52   |
|                      |     |     |     |     |     |     |      |
|                      | (9  | (   | (   | (   | (   | (   | (1   |
|                      | 2%) | 8%) | 0%) | 0%) | 0%) | 0%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| Training             | 14  | 0   | 1   | 0   | 0   | 0   | 15   |
|                      |     |     |     |     |     |     |      |
|                      | (9  | (   | (   | (   | (   | (   | (1   |
|                      | 3%) | 0%) | 7%) | 0%) | 0%) | 0%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| Production Planning  | 106 | 16  | 4   | 4   | 2   | 2   | 134  |
|                      |     |     |     |     |     |     |      |
|                      | (7  | (1  | (   | (   | (1. | (1. | (1   |
|                      | 9%) | 2%) | 3%) | 3%) | 5%) | 5%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| Engineering          | 70  | 14  | 13  | 2   | 1   | 0   | 100  |
|                      |     |     |     |     |     |     |      |
|                      | (7  | (1  | (1  | (   | (   | (   | (1   |
|                      | 0%) | 4%) | 3%) | 2%) | 1%) | 0%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| **SITE SUPPORT**     | *   | *   | **4 | **1 | **  | **  | **8  |
|                      | *71 | *10 | 5** | 5** | 6** | 2** | 79** |
|                      | 1** | 0** |     |     |     |     |      |
|                      |     |     | **  | **  | **  | **  | **   |
|                      | **( | **( | (5% | (2% | (1% | (0% | (100 |
|                      | 81% | 11% | )** | )** | )** | )** | %)** |
|                      | )** | )** |     |     |     |     |      |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| Laundry              | 42  | 5   | 1   | 0   | 0   | 0   | 48   |
|                      |     |     |     |     |     |     |      |
|                      | (8  | (1  | (   | (   | (   | (   | (1   |
|                      | 8%) | 0%) | 2%) | 0%) | 0%) | 0%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| Janitorial           | 52  | 11  | 1   | 1   | 0   | 0   | 65   |
|                      |     |     |     |     |     |     |      |
|                      | (8  | (1  | (1. | (1. | (   | (   | (1   |
|                      | 0%) | 7%) | 5%) | 5%) | 0%) | 0%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| Landfill             | 29  | 1   | 0   | 0   | 0   | 0   | 30   |
|                      |     |     |     |     |     |     |      |
|                      | (9  | (   | (   | (   | (   | (   | (1   |
|                      | 7%) | 3%) | 0%) | 0%) | 0%) | 0%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| Facility Maintenance | 96  | 21  | 9   | 3   | 1   | 0   | 130  |
|                      |     |     |     |     |     |     |      |
|                      | (7  | (1  | (   | (   | (   | (   | (1   |
|                      | 4%) | 6%) | 7%) | 2%) | 1%) | 0%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| Analytical           | 144 | 14  | 8   | 0   | 1   | 0   | 167  |
| Laboratories         |     |     |     |     |     |     |      |
|                      | (8  | (   | (   | (   | (   | (   | (1   |
|                      | 6%) | 8%) | 5%) | 0%) | 1%) | 0%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| S                    | 122 | 10  | 0   | 0   | 0   | 0   | 132  |
| hip/Receive/Material |     |     |     |     |     |     |      |
| Handle               | (9  | (   | (   | (   | (   | (   | (1   |
|                      | 2%) | 8%) | 0%) | 0%) | 0%) | 0%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| Wastewater Treatment | 27  | 8   | 9   | 2   | 0   | 0   | 46   |
|                      |     |     |     |     |     |     |      |
|                      | (5  | (1  | (2  | (   | (   | (   | (1   |
|                      | 9%) | 7%) | 0%) | 4%) | 0%) | 0%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| Store (supply) Rooms | 31  | 1   | 0   | 0   | 0   | 0   | 32   |
|                      |     |     |     |     |     |     |      |
|                      | (9  | (   | (   | (   | (   | (   | (1   |
|                      | 7%) | 3%) | 0%) | 0%) | 0%) | 0%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| Security             | 27  | 3   | 1   | 0   | 0   | 0   | 31   |
|                      |     |     |     |     |     |     |      |
|                      | (8  | (1  | (   | (   | (   | (   | (1   |
|                      | 7%) | 0%) | 3%) | 0%) | 0%) | 0%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| Boiler Operators     | 5   | 5   | 8   | 0   | 0   | 0   | 18   |
|                      |     |     |     |     |     |     |      |
|                      | (2  | (2  | (4  | (   | (   | (   | (1   |
|                      | 8%) | 8%) | 4%) | 0%) | 0%) | 0%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| Facility Engineering | 105 | 7   | 1   | 2   | 1   | 0   | 116  |
|                      |     |     |     |     |     |     |      |
|                      | (9  | (   | (   | (   | (   | (   | (1   |
|                      | 0%) | 6%) | 1%) | 2%) | 1%) | 0%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| Cafeteria            | 14  | 2   | 0   | 0   | 0   | 0   | 16   |
|                      |     |     |     |     |     |     |      |
|                      | (8  | (1  | (   | (   | (   | (   | (1   |
|                      | 8%) | 2%) | 0%) | 0%) | 0%) | 0%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| Decontamination      | 17  | 12  | 7   | 7   | 3   | 2   | 48   |
|                      |     |     |     |     |     |     |      |
|                      | (3  | (2  | (1  | (1  | (   | (   | (1   |
|                      | 5%) | 5%) | 5%) | 5%) | 6%) | 4%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| **PRODUCTION         | *   | *   | **8 | **4 | **3 | **4 | **8  |
| SUPPORT**            | *47 | *12 | 8** | 9** | 8** | 5** | 10** |
|                      | 0** | 0** |     |     |     |     |      |
|                      |     |     | **( | **  | **  | **  | **   |
|                      | **( | **( | 11% | (6% | (5% | (5% | (100 |
|                      | 58% | 15% | )** | )** | )** | )** | %)** |
|                      | )** | )** |     |     |     |     |      |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| Scrap Recycling      | 14  | 26  | 30  | 14  | 11  | 16  | 111  |
|                      |     |     |     |     |     |     |      |
|                      | (1  | (2  | (2  | (1  | (1  | (1  | (1   |
|                      | 3%) | 3%) | 7%) | 3%) | 0%) | 4%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| *Inventory Control   | 3   | 7   | 5   | 0   | 0   | 1   | 16   |
| Center*              |     |     |     |     |     |     |      |
|                      | (1  | (4  | (3  | (   | (   | (   | (1   |
|                      | 9%) | 4%) | 1%) | 0%) | 0%) | 6%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| *Scrap Reclamation*  | 3   | 2   | 9   | 4   | 5   | 3   | 26   |
|                      |     |     |     |     |     |     |      |
|                      | (1  | (   | (3  | (1  | (1  | (1  | (1   |
|                      | 1%) | 8%) | 5%) | 5%) | 9%) | 2%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| *Leaching*           | 1   | 0   | 2   | 1   | 0   | 2   | 6    |
|                      |     |     |     |     |     |     |      |
|                      | (1  | (   | (3  | (1  | (   | (3  | (1   |
|                      | 7%) | 0%) | 3%) | 7%) | 0%) | 3%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| *Resource Recovery*  | 7   | 17  | 14  | 9   | 6   | 10  | 63   |
|                      |     |     |     |     |     |     |      |
|                      | (1  | (2  | (2  | (1  | (1  | (1  | (1   |
|                      | 1%) | 7%) | 2%) | 4%) | 0%) | 6%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| Maintenance          | 155 | 65  | 43  | 29  | 26  | 27  | 345  |
|                      |     |     |     |     |     |     |      |
|                      | (4  | (1  | (1  | (   | (   | (   | (1   |
|                      | 5%) | 9%) | 2%) | 8%) | 8%) | 8%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| *Production          | 109 | 50  | 25  | 16  | 21  | 11  | 232  |
| Equipment*           |     |     |     |     |     |     |      |
|                      | (4  | (2  | (1  | (   | (   | (   | (1   |
|                      | 7%) | 1%) | 1%) | 7%) | 9%) | 5%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| *Furnaces and Tools* | 6   | 5   | 16  | 12  | 5   | 14  | 58   |
|                      |     |     |     |     |     |     |      |
|                      | (1  | (   | (2  | (2  | (   | (2  | (1   |
|                      | 0%) | 9%) | 7%) | 1%) | 9%) | 4%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| *Molds and Dies*     | 40  | 10  | 2   | 1   | 0   | 2   | 55   |
|                      |     |     |     |     |     |     |      |
|                      | (7  | (1  | (   | (   | (   | (   | (1   |
|                      | 3%) | 8%) | 4%) | 2%) | 0%) | 3%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| Research and         | 91  | 15  | 10  | 2   | 0   | 1   | 119  |
| Development          |     |     |     |     |     |     |      |
|                      | (7  | (1  | (   | (   | (   | (   | (1   |
|                      | 6%) | 3%) | 8%) | 2%) | 0%) | 1%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| QA/QC/Inspection     | 210 | 14  | 5   | 4   | 1   | 1   | 235  |
|                      |     |     |     |     |     |     |      |
|                      | (8  | (   | (   | (   | (0. | (0. | (1   |
|                      | 9%) | 6%) | 2%) | 2%) | 5%) | 5%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| **COLD WORK**        | *   | *   | **9 | **1 | **2 | **1 | **6  |
|                      | *34 | *11 | 1** | 8** | 2** | 0** | 06** |
|                      | 9** | 6** |     |     |     |     |      |
|                      |     |     | **( | **  | **  | **  | **   |
|                      | **( | **( | 15% | (3% | (3% | (2% | (100 |
|                      | 58% | 19% | )** | )** | )** | )** | %)** |
|                      | )** | )** |     |     |     |     |      |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| Rolling              | 24  | 2   | 3   | 0   | 1   | 0   | 30   |
|                      |     |     |     |     |     |     |      |
|                      | (8  | (   | (1  | (   | (   | (   | (1   |
|                      | 0%) | 7%) | 0%) | 0%) | 3%) | 0%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| Straightening        | 42  | 7   | 3   | 2   | 2   | 0   | 56   |
|                      |     |     |     |     |     |     |      |
|                      | (7  | (1  | (   | (   | (   | (   | (1   |
|                      | 5%) | 2%) | 5%) | 4%) | 4%) | 0%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| Drawing              | 26  | 5   | 0   | 0   | 0   | 0   | 31   |
|                      |     |     |     |     |     |     |      |
|                      | (8  | (1  | (   | (   | (   | (   | (1   |
|                      | 4%) | 6%) | 0%) | 0%) | 0%) | 0%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| Mix Makeup (furnace  | 14  | 9   | 17  | 5   | 5   | 1   | 51   |
| charge)              |     |     |     |     |     |     |      |
|                      | (2  | (1  | (3  | (1  | (1  | (   | (1   |
|                      | 7%) | 8%) | 3%) | 0%) | 0%) | 2%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| Machining            | 243 | 93  | 68  | 11  | 14  | 9   | 438  |
|                      |     |     |     |     |     |     |      |
|                      | (5  | (2  | (1  | (   | (   | (   | (1   |
|                      | 5%) | 1%) | 6%) | 3%) | 3%) | 2%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| *Billet Preparation* | 38  | 29  | 13  | 4   | 4   | 2   | 90   |
|                      |     |     |     |     |     |     |      |
|                      | (4  | (3  | (1  | (4. | (4. | (   | (1   |
|                      | 2%) | 2%) | 5%) | 5%) | 5%) | 2%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| *Alloys*             | 151 | 40  | 20  | 1   | 2   | 2   | 216  |
|                      |     |     |     |     |     |     |      |
|                      | (7  | (1  | (   | (   | (   | (   | (1   |
|                      | 0%) | 8%) | 9%) | 1%) | 1%) | 1%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| *High Beryllium*     | 54  | 24  | 35  | 6   | 8   | 5   | 132  |
|                      |     |     |     |     |     |     |      |
|                      | (4  | (1  | (2  | (   | (   | (   | (1   |
|                      | 1%) | 8%) | 6%) | 5%) | 6%) | 4%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| **HOT WORK**         | *   | **5 | **2 | **  | **  | **  | **2  |
|                      | *20 | 6** | 9** | 6** | 0** | 1** | 97** |
|                      | 5** |     |     |     |     |     |      |
|                      |     | **( | **( | **  | **  | **  | **   |
|                      | **( | 19% | 10% | (2% | (0% | (0% | (100 |
|                      | 69% | )** | )** | )** | )** | )** | %)** |
|                      | )** |     |     |     |     |     |      |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| Hot                  | 109 | 33  | 7   | 1   | 0   | 0   | 150  |
| Rolling/Extrusion    |     |     |     |     |     |     |      |
|                      | (7  | (2  | (   | (   | (   | (   | (1   |
|                      | 3%) | 2%) | 4%) | 1%) | 0%) | 0%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| Annealing            | 37  | 16  | 10  | 1   | 0   | 0   | 64   |
|                      |     |     |     |     |     |     |      |
|                      | (5  | (2  | (1  | (   | (   | (   | (1   |
|                      | 8%) | 5%) | 6%) | 1%) | 0%) | 0%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| Welding              | 0   | 4   | 6   | 4   | 0   | 1   | 15   |
|                      |     |     |     |     |     |     |      |
|                      | (   | (2  | (4  | (2  | (   | (   | (1   |
|                      | 0%) | 7%) | 0%) | 7%) | 0%) | 6%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| Pickling (↑          | 40  | 3   | 4   | 0   | 0   | 0   | 47   |
| temperatures)        |     |     |     |     |     |     |      |
|                      | (8  | (   | (   | (   | (   | (   | (1   |
|                      | 5%) | 6%) | 9%) | 0%) | 0%) | 0%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| Degreasing (↑        | 19  | 0   | 2   | 0   | 0   | 0   | 21   |
| temperature)         |     |     |     |     |     |     |      |
|                      | (9  | (   | (1  | (   | (   | (   | (1   |
|                      | 0%) | 0%) | 0%) | 0%) | 0%) | 0%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| **POWDERING**        | **  | **1 | **2 | **1 | **1 | **  | **   |
|                      | 8** | 3** | 2** | 4** | 1** | 4** | 72** |
|                      |     |     |     |     |     |     |      |
|                      | **( | **( | **( | **( | **( | **  | **   |
|                      | 11% | 18% | 31% | 19% | 15% | (6% | (100 |
|                      | )** | )** | )** | )** | )** | )** | %)** |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| Operator/Impact      | 5   | 1   | 6   | 6   | 7   | 1   | 26   |
| Grinding             |     |     |     |     |     |     |      |
|                      | (1  | (   | (2  | (2  | (2  | (   | (1   |
|                      | 9%) | 4%) | 3%) | 3%) | 7%) | 4%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| Compact              | 3   | 6   | 5   | 0   | 3   | 2   | 19   |
| Loading/Sintering    |     |     |     |     |     |     |      |
|                      | (1  | (3  | (2  | (   | (1  | (1  | (1   |
|                      | 6%) | 2%) | 6%) | 0%) | 6%) | 0%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| NNS (operator &      | 0   | 6   | 11  | 8   | 1   | 1   | 27   |
| welder)              |     |     |     |     |     |     |      |
|                      | (   | (2  | (4  | (2  | (   | (   | (1   |
|                      | 0%) | 2%) | 1%) | 9%) | 4%) | 4%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| **CHEMICAL           | **  | **  | **1 | **  | **  | **  | **   |
| OPERATIONS**         | 1** | 2** | 0** | 4** | 2** | 1** | 20** |
|                      |     |     |     |     |     |     |      |
|                      | **  | **( | **( | **( | **( | **  | **   |
|                      | (5% | 10% | 50% | 20% | 10% | (5% | (100 |
|                      | )** | )** | )** | )** | )** | )** | %)** |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| Beryllium Sulfate    | 1   | 2   | 10  | 4   | 2   | 1   | 20   |
| Salt (GC salt and    |     |     |     |     |     |     |      |
| wet screen           | (   | (1  | (5  | (2  | (1  | (   | (1   |
| operators)           | 5%) | 0%) | 0%) | 0%) | 0%) | 5%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| **FURNACE            | **  | **2 | **4 | **4 | **2 | **3 | **1  |
| OPERATIONS**         | 8** | 0** | 2** | 6** | 5** | 1** | 72** |
|                      |     |     |     |     |     |     |      |
|                      | **  | **( | **( | **( | **( | **( | **   |
|                      | (5% | 12% | 24% | 27% | 14% | 18% | (100 |
|                      | )** | )** | )** | )** | )** | )** | %)** |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| Alloy Induction      | 5   | 13  | 31  | 26  | 13  | 9   | 97   |
|                      |     |     |     |     |     |     |      |
|                      | (   | (1  | (3  | (2  | (1  | (   | (1   |
|                      | 5%) | 3%) | 2%) | 7%) | 4%) | 9%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| Alloy Arc            | 0   | 1   | 6   | 14  | 7   | 10  | 38   |
|                      |     |     |     |     |     |     |      |
|                      | (   | (   | (1  | (3  | (1  | (2  | (1   |
|                      | 0%) | 3%) | 6%) | 7%) | 8%) | 6%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| High Beryllium       | 0   | 3   | 2   | 1   | 2   | 1   | 9    |
| Vacuum Cast          |     |     |     |     |     |     |      |
|                      | (   | (3  | (2  | (1  | (2  | (1  | (1   |
|                      | 0%) | 4%) | 2%) | 1%) | 2%) | 1%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| High Beryllium       | 0   | 0   | 0   | 4   | 0   | 9   | 13   |
| Atomization          |     |     |     |     |     |     |      |
|                      | (   | (   | (   | (3  | (   | (6  | (1   |
|                      | 0%) | 0%) | 0%) | 1%) | 0%) | 9%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| Beryllium Oxide      | 3   | 3   | 3   | 1   | 3   | 2   | 15   |
|                      |     |     |     |     |     |     |      |
|                      | (2  | (2  | (2  | (   | (2  | (1  | (1   |
|                      | 0%) | 0%) | 0%) | 7%) | 0%) | 3%) | 00%) |
+----------------------+-----+-----+-----+-----+-----+-----+------+
| ^a^ Full-shift       |     |     |     |     |     |     |      |
| sample results are   |     |     |     |     |     |     |      |
| based on the actual  |     |     |     |     |     |     |      |
| sample duration.     |     |     |     |     |     |     |      |
| Full-shift means a   |     |     |     |     |     |     |      |
| sample duration of   |     |     |     |     |     |     |      |
| 360 minutes or       |     |     |     |     |     |     |      |
| longer.              |     |     |     |     |     |     |      |
|                      |     |     |     |     |     |     |      |
| ^b^ Non-detected     |     |     |     |     |     |     |      |
| results are reported |     |     |     |     |     |     |      |
| at one-half the      |     |     |     |     |     |     |      |
| analytical limit of  |     |     |     |     |     |     |      |
| detection.           |     |     |     |     |     |     |      |
|                      |     |     |     |     |     |     |      |
| ↑ means elevated     |     |     |     |     |     |     |      |
| bath/solvent         |     |     |     |     |     |     |      |
| temperatures.        |     |     |     |     |     |     |      |
|                      |     |     |     |     |     |     |      |
| NNS means            |     |     |     |     |     |     |      |
| Near-Net-Shape.      |     |     |     |     |     |     |      |
|                      |     |     |     |     |     |     |      |
| Source: Brush        |     |     |     |     |     |     |      |
| Wellman, 2004        |     |     |     |     |     |     |      |
+----------------------+-----+-----+-----+-----+-----+-----+------+

**3.1 ADMINISTRATIVE**

As shown in Table 3-2, the median exposure level for administrative
workers is 0.05 µg/m^3^ with a mean of 0.10 µg/m^3^ and a range of 0.05
µg/m^3^ to 4.54 µg/m^3^. These values represent a total of 981
full-shift PBZ total beryllium levels reported for workers categorized
in administrative work groups. Administrative workers include managers,
supervisors, secretaries, office workers, and professional support staff
such as engineering, production planning, medical, and environmental
health and safety personnel. These workers typically have their offices
in administrative buildings and may or may not interface with production
operations by entering regulated work areas of the facility. In
addition, employees wearing company-provided (production) work clothing
may not enter some administrative offices (east administration). Other
offices (west administration) are open to production workers and
administrative employees working in these areas must also wear
company-provided work clothing.

The median exposure levels for all nine work groups included in the
administrative job category are less than the lowest proposed PEL option
of 0.1 μg/m^3^. Additionally, the maximum exposure levels for three of
the nine work groups (human resources, information systems, and credit
union personnel) do not exceed 0.1 μg/m^3^. The highest maximum exposure
levels are reported for production planning (4.54 μg/m^3^), operations
management (2.68 μg/m^3^), engineering (1.98 μg/m^3^), and environmental
health and safety (1.88 μg/m^3^) personnel. These groups of workers are
more likely to spend a portion of their time in regulated work areas.
Although no information is available to explain these higher levels,
these data clearly show that non-production administrative employees
have the potential for elevated exposure levels due to their
interactions with production equipment, processes, and/or workers.

Table 3-3 shows that 85 percent of the full-shift PBZ total beryllium
levels for non-production workers classified in the administrative job
category are less than or equal to the lowest proposed PEL option of 0.1
μg/m^3^. Fifteen percent of the exposure levels are greater than 0.1
μg/m^3^, six percent of the exposure levels are greater than 0.2
μg/m^3^, and about one percent of the levels exceed 1 μg/m^3^.

Administrative workers that enter production areas of the facility must
abide by the same exposure controls and procedures applicable to
production workers including the use of company-provided work clothing
(that is laundered on site), respiratory protection, and showers at the
end of the work shift and/or when leaving regulated work areas.
Beryllium contamination that could be transferred from regulated areas
of the facility to administrative areas is controlled through the use of
migration control procedures. Work tasks and procedures are evaluated to
identify the potential for beryllium contamination of skin and clothing
and appropriate interventions are developed and implemented. Examples of
beryllium migration control techniques in place include the following:

-   Personal protective clothing (e.g., work clothing and shoes,
    coveralls, lab coats, gloves, head and shoe coverings);

-   Shoe cleaners and tack (sticky) mats;

-   Air showers (not plant-wide);

-   Personal hygiene (e.g., hand washing and showers);

-   Housekeeping (HEPA filtered vacuum systems and wet methods; work
    surfaces and equipment "visibly" clean).

Additionally, employees that wear their personal street clothing and
work in east administrative areas can interact with personnel in west
administrative areas through the use of segregated transition zones.
Employees enter a clean room, don clean shoe covers (booties), a lab
coat, and then step onto a tack mat to enter west administrative areas.
Upon leaving, employees enter a "dirty" room where they remove their
shoe covers/lab coat, wash their hands, and step onto a tack mat to exit
back to their offices.

The exposure levels of most administrative workers are typically less
than the lowest proposed PEL option of 0.1 µg/m^3^. Implementing or
improving engineering and work practice controls that are necessary for
production workers will likewise result in reduced exposures for
administrative workers who receive their exposures primarily from
entering regulated work areas. For those administrative workers that do
not enter production areas, improvements in beryllium migration control
will be required to achieve additional reductions in exposure.

**3.2 SITE SUPPORT**

Table 3-2 shows that the median exposure level for site support workers
is 0.05 µg/m^3^ with a mean of 0.11 µg/m^3^ and a range of 0.05 µg/m^3^
to 4.22 µg/m^3^. These values represent a total of 879 full-shift PBZ
total beryllium levels reported for workers categorized in site support
work groups. These workers typically include those involved in site-wide
support services such as cleaning (e.g., laundry, janitorial,
decontamination), facility/site operations (e.g., boilers, maintenance,
wastewater treatment, landfill), shipping/receiving/ material handling,
supply rooms, analytical laboratories, security, and the cafeteria.

The median exposure levels for two out of 13 work groups included in the
site support job category exceed the lowest proposed PEL option of 0.1
µg/m^3^. These work groups include decontamination workers (median
exposure level of 0.18 µg/m^3^) and boiler operators (median exposure
level of 0.16 µg/m^3^). Wastewater treatment workers have a median
exposure level close to 0.1 µg/m^3^ (0.09 µg/m^3^) and all other site
support work groups have median exposure levels below the lowest
proposed PEL option.

Table 3-2 also shows that all employees categorized as site support
workers have maximum exposure levels greater than 0.1 µg/m^3^. The
highest maximum exposure levels are reported for decontamination (4.22
µg/m^3^), laboratory (1.52 µg/m^3^), facility maintenance (1.23 µg/m^3^)
and facility engineering (1.13 µg/m^3^) workers.

As shown in Table 3-3, 81 percent of the full-shift PBZ total beryllium
exposure results for non-production workers classified in the site
support job category are less than or equal to the lowest proposed PEL
option of 0.1 µg/m^3^. Nineteen percent of the exposure results are
greater than 0.1 µg/m^3^, eight percent of the exposure results are
greater than 0.2 μg/m^3^, and about one percent of the levels exceed 1
µg/m^3^.

***Decontamination:*** Decontamination workers historically performed
large-scale surface cleaning in places that did not get cleaned
frequently such as room and equipment surfaces eight feet and above in
height in regulated work areas. Entire areas were shut down for cleaning
based on a predetermined work schedule. Decontamination workers do not
perform cleaning tasks typically associated with the janitorial staff
such as cleaning offices, meeting/break rooms, and the toilets.
Currently, the decontamination crew consists of four to six workers that
primarily perform large equipment decontamination. This equipment
includes cranes that need to be serviced or inspected, and equipment
that needs to leave the site for service or repair such as electric
motors, heavy equipment (e.g., a front-end loader), and vehicles.
Decontamination is a daily activity for these workers. For example, one
or more cranes are "deconned" on nearly a daily basis for service or
inspection because the site has so many (i.e., approximately 300
cranes). Decontamination workers clean contaminated equipment surfaces
by disrupting the surface contamination with one or more cleaning
techniques. These techniques include HEPA vacuuming and various wet
cleaning methods (e.g., wet wiping, high and low-pressure water
washing). Cleaning procedures are situation-specific, but typically
include HEPA vacuuming first, and then wet wiping. A high power
diesel-powered vacuum mounted on a trailer is also available for
cleaning extensive gross surface contamination. Decontamination workers
presumably receive higher exposures when cleaning more heavily
contaminated equipment. Higher exposure levels might also be associated
with worker technique and/or improper work practices (such as using high
pressure water washing before gross cleaning with a vacuum and initial
wet wiping).

***Decontamination -- Additional Controls:*** As shown in Table 3-2, the
median exposure level for decontamination workers is 0.18 μg/m^3^.
Tables 3-3 indicates that 35 percent of the exposure levels for these
workers are less than or equal to the lowest proposed PEL option of 0.1
μg/m^3^. Sixty-five percent of the exposure levels are greater than 0.1
μg/m^3^, 40 percent of the exposure levels are greater than 0.2 μg/m^3^,
and ten percent of the levels exceed 1 μg/m^3^. Additional controls will
be required to reduce operator exposures. Based on the available
information, these additional controls include:

-   Enhancing work practices through operator training, work practice
    modifications, and/or better enforcement/supervision (for example,
    workers need to follow the standard operating procedure developed
    for decontamination activities); and

-   Reducing the level of contamination associated with the workplace
    (i.e., better source control). Source control improvements will
    reduce the level of contamination associated with the workplace and
    might reduce the frequency and/or the magnitude of cleaning
    required.

*Enhanced Work Practices*: Excellent work practice controls must be
established, taught to employees, and then enforced. Consequently, work
practice improvements might include additional employee training, better
enforcement of existing procedures, and/or the development of new or
revised procedures to better control workplace exposures. One industry
expert suggests that beryllium exposure levels can typically be reduced
by approximately 20 to 50 percent through improved work practice
controls alone (Kent, 2005).

During testimony before the Department of Labor, NIOSH officials
addressed issues for a proposed OSHA standard on beryllium. In addition
to the use of engineering controls, NIOSH recommended that work
practices for reducing beryllium exposures at or below the proposed
standard be implemented. Two NIOSH recommendations relevant to
decontamination workers include (1) provisions for a decontamination
chamber for beryllium contaminated equipment requiring maintenance; and
(2) clearly explained and carefully supervised work practices. To be
effective, NIOSH stated that work practices must be clearly explained
and carefully supervised (NIOSH, 1977). A leak tight decontamination
chamber might be an effective means of reducing worker exposures to
beryllium. Although such a device might have limited applications for
very large equipment, its use where practical might result in exposure
levels less than 0.1 µg/m^3^.

Maples et al. (1982) report on the effectiveness of employee training
and motivation programs in reducing exposure to inorganic lead and lead
alkyls in a pilot 12-month program in an alkyl lead production facility.
Employees included in the program included 35 foremen responsible for
alkyl lead production. The objective of the program was to reduce
elevated blood lead and urine lead levels through (1) intensive training
on the industrial hygiene aspects of lead and (2) motivating workers to
minimize exposure by using good work practices. Group meetings were held
on a monthly basis and the importance of good work practices and
personal hygiene were stressed. Examples included (1) keeping
fingernails short and clean; (2) washing hands and face before eating,
drinking, and smoking; (3) changing to clean work clothing on a daily
basis; (4) informing workers that wiping the face with a shirt sleeve to
remove perspiration could result in ingestion of lead particulate
(and/or inhalation); and (5) emphasizing the importance of proper use
and care of respirators, especially the need to clean dust from the
respirator after use. Biological samples were collected on a monthly
basis for urine and bimonthly for blood. The blood and urine lead values
were statistically evaluated and discussed with workers during group
meetings. The workers focused their discussions on the work areas of
employees with higher or increasing blood or urine leads. After a
12-month period the results showed a 24 percent reduction in blood lead
levels and a 40 percent reduction in urine lead levels, both indicators
of exposure to organic and inorganic lead. The authors concluded that an
employee training and motivation program appeared to be an effective
method for reducing employee exposure to chemicals and that the capital
investment was minimal compared to engineering controls. Maples et al.
also report that the foremen in the pilot program shared the information
they learned with the employees reporting to them and applied many of
the training and motivation techniques to their groups with significant
success. Eventually the training and motivation program was expanded to
include all employees with elevated blood and urine lead levels. The
investigators continued to observe a reduction in blood and urine lead
levels and noted that the program can be tailored to an employee's
specific job when working with employees on a one-on-one basis as
opposed to large groups. If an employee's blood and urine lead levels
remain elevated, a job safety analysis is conducted to address the work
practices resulting in higher exposures.

At a western copper smelter and arsenic trioxide production facility,
the sole use of engineering controls to reduce employee exposure to
arsenic to within the current PEL (10 µg/m^3^) was not feasible due to
the use of high arsenic bearing ores, the manufacture of arsenic
trioxide, and the age of the facility (Cant et al., 1982). To supplement
engineering controls at the contaminant sources, the facility
implemented an exposure control program consisting of regulated work
areas, worker rotation, personal protective equipment (including
respiratory protection), exposure monitoring, biological monitoring, and
clean room/lunch rooms. The authors note that employee acceptance and
understanding is essential to the success of a program of this nature
where engineering controls cannot completely eliminate exposures.
Consequently, a formal training program was implemented to ensure that
employees understand all of the program elements with emphasis on the
importance of personal hygiene in reducing arsenic absorption. A urinary
biological monitoring program was also implemented as a means of
internal program evaluation. Urinary arsenic levels above a designated
level prompted an investigation of that employee's work practices,
personal hygiene, respirator usage, etc. Corrective actions, which might
include transfer to an area with less exposure, were taken. For the nine
year time period from 1970 through 1978, the facility experienced about
a 49 percent reduction in employee urinary arsenic levels. The greatest
reduction occurred for the time period 1975 through 1977 when the formal
training program was implemented. Over this time period, average annual
urinary arsenic levels decreased by approximately 30 percent. The
authors concluded that this significant reduction in urinary arsenic
levels demonstrated the importance of a stringent training and internal
evaluation program when exposures cannot be significantly reduced by
engineering controls alone.

Based on the available information, ERG preliminarily estimates that
enhanced work practices might achieve an average exposure reduction of
32 percent for those workers whose exposure is primarily associated with
work practice issues. This estimated exposure reduction is based on
information provided by Kent (2005) and the exposure reductions
described by Maples et al. (1982) and Cant et al. (1982).

*Reducing the Level of Contamination in the Workplace*: A number of
pharmaceutical companies control exposure to the dusts of potent
pharmaceutical active ingredients by assigning these compounds to one of
five performance-based exposure control limit (PB-ECL) categories
(Naumann et al., 1996). Each category in turn dictates the level of
exposure control that is necessary to maintain risks at acceptable
levels. Exposure control is achieved through a combination of
engineering controls, administrative procedures, and safe handling
practices known to provide the necessary level of control to protect
employees and the environment. Personal protective equipment is used
only as a redundant control measure. The suitability of various
combinations of controls was determined by evaluating a large database
of industrial hygiene monitoring data (air monitoring and wipe test
data) and professional judgment. Additionally, air monitoring and wipe
test data are used on an on-going basis to continually validate the
effectiveness of PB-ECL category control strategies. The higher PB-ECL
categories provide a greater margin of safety for increasingly hazardous
compounds by incorporating increasing levels of redundancy in
protection.

Assignment of pharmaceutical compounds to PB-ECL categories takes into
consideration many criteria such as potency, warning symptoms and onset,
severity of acute and chronic health effects, sensitization, medical
treatability, reversibility, disability, and others. The control
strategies (either in whole or part) specified by Naumann et al. (1996)
for PB-ECL categories 3 through 5 have applicability in beryllium
operations. Compounds assigned to PB-ECL Category 3 begin to require
significant containment for exposure control (i.e., essentially no open
handling, closed systems should be used). Typical occupational exposure
limits range from 1 µg/m^3^ to 100 µg/m^3^. PB-ECL Category 3 compounds
have reversible short-term effects and may produce non-life-threatening
(or non-incapacitating) effects that are slowly or not completely
reversible with chronic exposure.

Exposure limits are less than 1 µg/m^3^ and a total containment approach
is used to control exposures (i.e., no open handling, closed systems
must be used) for PB-ECL Category 4 compounds. These compounds may
produce life-threatening effects with incapacitating symptoms requiring
immediate medical intervention. They may also have short or long-term
effects that are irreversible and disabling.

Compounds in PB-ECL Category 5 represent the most toxic substances with
exposure limits of 0.1 µg/m^3^ or less. These compounds produce
life-threatening effects requiring immediate medical intervention. They
might also produce irreversible health effects that are severely
disabling or significantly shorten life-expectancy. Exposures to PB-ECL
Category 5 compounds would be controlled through state-of-the-art
facilities utilizing closed processes, robotics, and remote-controlled
operations. No manual operations or human intervention would be allowed.

The control matrix specified by Naumann et al. (1996) for PB-ECL
Categories 3 through 5 is presented in Table 3-4. This matrix includes
information about general workplace controls and specific details
regarding the containment level; general ventilation; local exhaust
ventilation; work surfaces; maintenance, cleaning, waste disposal, and
decontamination. Personal protective equipment, industrial hygiene
monitoring, and medical surveillance are also addressed by Naumann et
al. but have not been included in Table 3-4. The authors conclude that
these strategies are useful for controlling exposures to PB-ECL Category
3 (or less) compounds and mandatory for Category 4 and 5 compounds.

The control matrix described above for pharmaceutical active ingredients
clearly includes criteria appropriate for beryllium exposure control. It
is possible that some control categories might not be suitable for
beryllium production because the quantities of hazardous materials used
and/or the scale of the operations in the pharmaceutical industry may be
smaller. It is also possible that some of the control categories might
be suitable for some aspects of beryllium production but not all. The
beryllium production industry currently utilizes control categories, or
variations of the control categories, that are specified in the
pharmaceutical model. For example, containment systems are utilized but
they might not meet zero leakage criteria; work practices have been
established but they might not be excellent work practices or carefully
supervised; many work areas are under negative pressure relative to
surrounding areas, but not all; and, local exhaust ventilation is
provided but it might not always meet the recommended design criteria.
It is reasonable to assume that some level of reduced workplace
contamination will occur if some source control improvements can be made
based on the control techniques specified in the pharmaceutical model.
Naumann et al. (1996) have indicated that strict adherence to their
control matrix can achieve exposure control limits of 0.1 µg/m^3^ in the
pharmaceutical industry. ERG therefore assumes that a minimum ten
percent reduction in decontamination worker exposure might be achieved
if some reductions can be made in workplace contamination. As previously
stated, source control improvements will reduce the level of
contamination associated with the workplace and might reduce the
frequency and/or the magnitude of cleaning required.

+----------+-------------------+-------------------+-------------------+
| **Table  |                   |                   |                   |
| 3-4.     |                   |                   |                   |
| General  |                   |                   |                   |
| Control  |                   |                   |                   |
| Matrix   |                   |                   |                   |
| for      |                   |                   |                   |
| Pharma   |                   |                   |                   |
| ceutical |                   |                   |                   |
| Active   |                   |                   |                   |
| Ing      |                   |                   |                   |
| redients |                   |                   |                   |
| Assigned |                   |                   |                   |
| to       |                   |                   |                   |
| P        |                   |                   |                   |
| erforman |                   |                   |                   |
| ce-Based |                   |                   |                   |
| Exposure |                   |                   |                   |
| Control  |                   |                   |                   |
| Limit    |                   |                   |                   |
| (PB-ECL) |                   |                   |                   |
| Ca       |                   |                   |                   |
| tegories |                   |                   |                   |
| 3        |                   |                   |                   |
| through  |                   |                   |                   |
| 5\***    |                   |                   |                   |
+==========+===================+===================+===================+
| **       | **PB-ECL Category | **PB-ECL Category | **PB-ECL Category |
| Selected | 3**               | 4**               | 5**               |
| Control  |                   |                   |                   |
| Cate     | **Exposure        | **Exposure        | **Exposure        |
| gories** | Control Limit 10  | Control Limit 1   | Control Limit 0.1 |
|          | µg/m^3^**         | µg/m^3^ or Less** | μg/m^3^ or Less** |
|          |                   |                   |                   |
|          | **(range 1 to 100 |                   |                   |
|          | µg/m^3^)**        |                   |                   |
+----------+-------------------+-------------------+-------------------+
| *        | Controlled access | Controlled access | Controlled access |
| *General | to the work area  | to the work area  | to the work area  |
| C        | is strongly       | is required.      | is required.      |
| oncept** | recommended.      |                   |                   |
|          |                   | Only people who   | Only people who   |
|          | Only people who   | have received     | have received     |
|          | have received     | training specific | training specific |
|          | training specific | to the compound   | to the compound   |
|          | to the compound   | will be admitted. | will be admitted. |
|          | will be admitted. |                   |                   |
|          |                   | Work surfaces are | Work surfaces are |
|          | Work surfaces are | to be             | to be             |
|          | to be             | decontaminated    | decontaminated    |
|          | decontaminated    | after all         | after all         |
|          | after all         | potentially       | potentially       |
|          | potentially       | high-risk         | high-risk         |
|          | high-risk         | activities.       | activities.       |
|          | activities.       |                   |                   |
|          |                   | Eating, drinking, | Eating, drinking, |
|          | Eating, drinking, | smoking, and      | smoking, and      |
|          | smoking, and      | applying          | applying          |
|          | applying          | cosmetics are not | cosmetics are not |
|          | cosmetics are not | permitted in the  | permitted in the  |
|          | permitted in the  | work area.        | work area.        |
|          | work area.        |                   |                   |
|          |                   | Excellent work    | Excellent work    |
|          | Excellent work    | practices must be | practices must be |
|          | practices must be | established,      | established,      |
|          | established,      | taught, and       | taught, and       |
|          | taught, and       | enforced.         | enforced.         |
|          | enforced.         |                   |                   |
|          |                   | Deviations from   | Deviations from   |
|          | Deviations from   | established       | established       |
|          | established       | practices cannot  | practices cannot  |
|          | practices cannot  | be tolerated.     | be tolerated.     |
|          | be tolerated.     |                   |                   |
|          |                   | Signs must be     | Signs must be     |
|          | Signs must be     | posted indicating | posted indicating |
|          | posted indicating | the compound in   | the compound in   |
|          | the compound in   | question and its  | question and its  |
|          | question and its  | associated        | associated        |
|          | associated        | hazards.          | hazards.          |
|          | hazards.          |                   |                   |
+----------+-------------------+-------------------+-------------------+
| **Con    | Open handling     | Open handling is  | Open handling is  |
| tainment | must be limited   | not permitted     | not permitted     |
| Level**  | to only very      | under any         | under any         |
|          | small quantities. | circumstances.    | circumstances.    |
|          |                   |                   |                   |
|          | Lab hoods and     | All operations    | All operations    |
|          | other open-face   | require the use   | require the use   |
|          | containment       | of an appropriate | of an appropriate |
|          | devices are       | containment       | containment       |
|          | acceptable when   | technology        | technology        |
|          | face velocities   | designed to       | designed to       |
|          | of at least 80    | prevent leakage   | prevent leakage   |
|          | linear fpm are    | to the workplace. | to the workplace. |
|          | achieved.         |                   |                   |
|          |                   | In general, glove | In general, glove |
|          | Partitions,       | boxes, totally    | boxes, totally    |
|          | barriers, and     | enclosed          | enclosed          |
|          | other partial     | processes, and    | processes, and    |
|          | containment       | materials         | materials         |
|          | technologies are  | transport systems | transport systems |
|          | required to       | would be          | would be          |
|          | prevent migration | expected.         | expected.         |
|          | of the compound   |                   |                   |
|          | to uncontrolled   |                   | All containment   |
|          | areas.            |                   | systems require   |
|          |                   |                   | leakage testing   |
|          |                   |                   | and must meet     |
|          |                   |                   | zero leakage      |
|          |                   |                   | criteria.         |
|          |                   |                   |                   |
|          |                   |                   | Remote operations |
|          |                   |                   | should be         |
|          |                   |                   | encouraged        |
|          |                   |                   | wherever          |
|          |                   |                   | possible.         |
|          |                   |                   |                   |
|          |                   |                   | Minimizing human  |
|          |                   |                   | interactions must |
|          |                   |                   | be the goal.      |
+----------+-------------------+-------------------+-------------------+
| *        | A minimum of 10   | A minimum of 12   | A minimum of 12   |
| *General | air changes per   | air changes per   | air changes per   |
| Venti    | hour is required. | hour is required. | hour is required. |
| lation** |                   |                   |                   |
|          | Air recirculation | Air recirculation | Air recirculation |
|          | is permitted in   | is not permitted. | is not permitted. |
|          | limited           |                   |                   |
|          | situations.       | Air flow must be  | Air flow must be  |
|          |                   | directed away     | directed away     |
|          | Air flow must be  | from the          | from the          |
|          | directed away     | operator's        | operator's        |
|          | from the          | breathing zone.   | breathing zone.   |
|          | operator's        |                   |                   |
|          | breathing zone.   | Air pressure must | Air pressure must |
|          |                   | be negative       | be negative       |
|          | Air pressure must | relative to       | relative to       |
|          | be negative       | surrounding       | surrounding       |
|          | relative to       | areas.            | areas.            |
|          | surrounding       |                   |                   |
|          | areas.            | Air locks with    | Double air locks  |
|          |                   | interlocked doors | with interlocked  |
|          |                   | are required to   | doors are         |
|          |                   | the processing    | required.         |
|          |                   | areas.            |                   |
+----------+-------------------+-------------------+-------------------+
| **Local  | LEV must be       | LEV must be       | LEV must be       |
| Exhaust  | provided at the   | provided at the   | provided at the   |
| Ven      | sources of        | sources of        | sources of        |
| tilation | contamination     | contamination     | contamination     |
| (LEV)**  | using ACGIH       | using ACGIH       | using ACGIH       |
|          | ventilation       | ventilation       | ventilation       |
|          | design criteria.  | design criteria.  | design criteria.  |
|          |                   |                   |                   |
|          | Exhaust must be   | Exhaust must be   | Exhaust must be   |
|          | HEPA-filtered to  | HEPA-filtered to  | HEPA-filtered to  |
|          | the outside.      | the outside.      | the outside.      |
+----------+-------------------+-------------------+-------------------+
| **Su     | Smooth,           | Smooth,           | Smooth,           |
| rfaces** | nonporous,        | nonporous,        | nonporous,        |
|          | minimal ledges,   | minimal ledges,   | minimal ledges,   |
|          | easily cleaned.   | easily cleaned.   | easily cleaned.   |
|          |                   |                   |                   |
|          |                   | Surfaces must be  | Surfaces must be  |
|          |                   | contiguous.       | contiguous.       |
+----------+-------------------+-------------------+-------------------+
| **Main   | Floor sweeping is | Floor sweeping is | Floor sweeping is |
| tenance, | not permitted for | not permitted for | not permitted for |
| cle      | cleaning powders. | cleaning powders. | cleaning powders. |
| aning,** |                   |                   |                   |
|          | Only HEPA vacuum  | Only HEPA vacuum  | Only HEPA vacuum  |
| **waste  | systems are used  | systems are used  | systems are used  |
| d        | prior to wet      | prior to wet      | prior to wet      |
| isposal, | mopping/cleaning. | mopping/cleaning. | mopping/cleaning. |
| and**    |                   |                   |                   |
|          | Chemical          | Chemical          | Chemical          |
| **d      | decontamination   | decontamination   | decontamination   |
| econtami | is not required   | is required if    | is required if    |
| nation** | nor is validated  | possible.         | possible.         |
|          | surface           |                   |                   |
|          | contamination     | Surface           | Surface           |
|          | testing.          | contamination     | contamination     |
|          |                   | testing is        | testing is        |
|          | All waste         | required for      | required for      |
|          | material must be  | deregulation of   | deregulation of   |
|          | double bagged and | the facility and  | the facility and  |
|          | clearly labeled   | equipment.        | equipment.        |
|          | according to      |                   |                   |
|          | applicable        | All waste         | All waste         |
|          | standards.        | material must be  | material must be  |
|          |                   | double bagged,    | double bagged,    |
|          | Material may not  | placed in a rigid | placed in a rigid |
|          | be crushed or     | container, and    | container, and    |
|          | shredded prior to | labeled according | labeled according |
|          | final disposal.   | to applicable     | to applicable     |
|          |                   | standards.        | standards.        |
|          | Clean-in-place    |                   |                   |
|          | systems for       | Material may not  | Material may not  |
|          | equipment are     | be crushed or     | be crushed or     |
|          | recommended       | shredded prior to | shredded prior to |
|          | wherever          | final disposal.   | final disposal.   |
|          | possible.         |                   |                   |
|          |                   | Clean-in-place    | Clean-in-place    |
|          | Safe change       | systems for       | systems for       |
|          | filters are       | equipment are     | equipment are     |
|          | required for all  | required wherever | required wherever |
|          | ventilation       | possible.         | possible.         |
|          | systems.          |                   |                   |
|          |                   | Safe change       | Safe change       |
|          | Wherever possible | filters are       | filters are       |
|          | equipment should  | required for all  | required for all  |
|          | be accessed for   | ventilation       | ventilation       |
|          | maintenance from  | systems.          | systems.          |
|          | outside of the    |                   |                   |
|          | containment area. | Wherever          | Wherever          |
|          |                   | possible,         | possible,         |
|          |                   | equipment should  | equipment should  |
|          |                   | be accessed for   | be accessed for   |
|          |                   | maintenance from  | maintenance from  |
|          |                   | outside of the    | outside of the    |
|          |                   | containment area. | containment area. |
+----------+-------------------+-------------------+-------------------+
| \*       |                   |                   |                   |
| Obtained |                   |                   |                   |
| from     |                   |                   |                   |
| Naumann  |                   |                   |                   |
| et al.,  |                   |                   |                   |
| 1996.    |                   |                   |                   |
| Though   |                   |                   |                   |
| not      |                   |                   |                   |
| p        |                   |                   |                   |
| resented |                   |                   |                   |
| in this  |                   |                   |                   |
| table,   |                   |                   |                   |
| Naumann  |                   |                   |                   |
| et al.   |                   |                   |                   |
| also     |                   |                   |                   |
| include  |                   |                   |                   |
| criteria |                   |                   |                   |
| for      |                   |                   |                   |
| personal |                   |                   |                   |
| pr       |                   |                   |                   |
| otective |                   |                   |                   |
| eq       |                   |                   |                   |
| uipment, |                   |                   |                   |
| in       |                   |                   |                   |
| dustrial |                   |                   |                   |
| hygiene  |                   |                   |                   |
| mon      |                   |                   |                   |
| itoring, |                   |                   |                   |
| and      |                   |                   |                   |
| medical  |                   |                   |                   |
| surv     |                   |                   |                   |
| eillance |                   |                   |                   |
| in their |                   |                   |                   |
| control  |                   |                   |                   |
| matrix   |                   |                   |                   |
| for      |                   |                   |                   |
| pharma   |                   |                   |                   |
| ceutical |                   |                   |                   |
| active   |                   |                   |                   |
| ingr     |                   |                   |                   |
| edients. |                   |                   |                   |
+----------+-------------------+-------------------+-------------------+

***Decontamination -- Conclusion:*** The median exposure result for
decontamination workers is 0.18 µg/m^3^. Table 3-3 suggests that 65
percent of decontamination workers have exposure levels that exceed the
lowest proposed PEL option of 0.1 µg/m^3^. Additional controls are
required to further reduce worker exposure. Enhanced work practices and
source control improvements are estimated to achieve a minimum combined
exposure reduction of 42 percent resulting in a median level of 0.1
µg/m^3^ for decontamination workers. Despite this reduction,
approximately 40 percent of decontamination workers might experience
exposure levels that exceed 0.1 µg/m^3^. For these workers, greater
reductions in exposure will be required that might be achieved through
further work practice and source control improvements. Additionally, as
recommended by NIOSH (1977) during its testimony before the DOL, using a
decontamination chamber for beryllium contaminated equipment requiring
service or maintenance might further reduce worker exposure. Although
such a device might have limited applications for very large equipment,
its use where practical might result in exposure levels less than 0.1
µg/m^3^. For some decontamination workers, respiratory protection likely
will be necessary to achieve compliance with the lower PEL options.

***Boiler:*** Boiler operators had higher median (0.16 µg/m^3^) and
maximum (0.48 µg/m^3^) exposure levels because the facility boilers are
physically located near other high contamination operations (i.e., the
boilers are out in the open, there is no boiler "room"). Operators
monitor the boilers from a small control room equipped with a window
air-conditioning unit. However, when operators leave the control room to
physically monitor or inspect the boilers, respiratory protection is
worn. Because of the proximity of the boiler control room to other high
exposure operations (i.e., the pebble plant, beryllium oxide furnaces,
and resource recovery recycling operation), contaminated air
infiltration was a potential concern and might also have been a factor
in the higher exposure levels reported for boiler operators. Subsequent
to the 1999 baseline exposure monitoring, the boilers were physically
isolated from two of the three nearby high exposure operations. The
pebble plant and the beryllium oxide furnaces were "walled off" from the
boilers. Additionally, HEPA air filtration was introduced to all pulpits
including the boiler control room. Boiler operator exposures are now
significantly lower and are estimated to be approximately one-tenth the
value of what they were (Kent, 2005).

***Boiler -- Additional Controls:*** As indicated in Table 3-3, 28
percent of the exposure levels for boiler operators are less than or
equal to the lowest proposed PEL option of 0.1 μg/m^3^. Seventy-two
percent of the exposure levels are greater than 0.1 μg/m^3^, and 44
percent of the exposure levels are greater than 0.2 μg/m^3^ but less
than or equal to 0.5 μg/m^3^. No exposure results exceed 0.5 μg/m^3^.
Additional controls will be required to reduce operator exposures. Based
on the available information, these additional controls include: (1)
eliminating the potential for contaminated air infiltration into the
boiler control room (e.g., by installing HEPA air filtration) and (2)
physically isolating the boilers from the nearby high exposure
operations. Together these additional controls are estimated to have
reduced the median exposure level of boiler operators to about 0.016
μg/m^3^ and the maximum exposure level to approximately 0.048 μg/m^3^.

***Boiler -- Conclusion:*** Boiler operators had elevated exposure
levels because the facility boilers are physically located near several
high contamination operations. By isolating two of the three nearby high
exposure operations and eliminating the potential for contaminated air
infiltration into the boiler control room, boiler operators achieved a
significant reduction in exposure. ERG preliminarily estimates that
these additional controls reduced boiler operator exposures to well
below the lowest proposed PEL option of 0.1 μg/m^3^.

***Wastewater Treatment:*** The industrial wastewater treatment facility
is in a separate building and there is no co-location issue associated
with worker exposures as noted with the boiler operators. Worker
exposures are due to the treatment plant and might be primarily
associated with the sludge cake operation (especially operating the
filter press and monitoring bag filling). Sludge contamination that has
been allowed to dry can become airborne very easily and is also a likely
source of beryllium exposure. Higher exposure levels for wastewater
treatment workers might be due entirely to work practice and
housekeeping issues.

***Wastewater Treatment -- Additional Controls:*** The median exposure
level for industrial wastewater treatment workers is approximately 0.1
μg/m^3^. As shown in Table 3-3, 59 percent of the exposure levels for
wastewater treatment workers are less than the lowest proposed PEL
option of 0.1 μg/m^3^. Forty-one percent of the exposure levels are
greater than 0.1 μg/m^3^, and 24 percent of the levels are greater than
0.2 μg/m^3^. No exposure results for wastewater treatment workers exceed
1.0 μg/m^3^. However, to reduce the exposures of all industrial
wastewater treatment workers to the lowest proposed PEL option,
additional controls are required. Based on the available information,
these additional controls include:

-   Enhancing work practices through operator training, work practice
    modifications, and/or better enforcement/supervision to minimize
    exposures associated with the sludge cake operation. For example,
    operators need to limit the number of times the sludge cake is
    pressed to avoid making it too dry. A dry cake can increase the
    amount of dust generated during sludge bag filling and directly
    affect worker exposure and/or contaminate the work environment.

-   Improving the level of housekeeping in the industrial wastewater
    treatment plant through more effective and/or more frequent
    cleaning.

As previously discussed (decontamination workers), ERG estimates that
enhanced work practices alone might achieve an average exposure
reduction of 32 percent for those exposures primarily attributed to work
practice issues. In regard to housekeeping-related exposures, NIOSH
repeatedly recommends effective housekeeping and appropriate cleaning
techniques (such as wet clean-up methods and/or vacuuming with an
approved HEPA filter vacuum) as a method to minimize worker exposure to
hazardous air contaminants such as asbestos, crystalline silica, and
heavy metals (NIOSH, 1990, 1991, and 2004). Additionally, OSHA general
industry standards for asbestos, inorganic arsenic, lead, and cadmium
all specify that work surfaces are to be maintained as free as
practicable of accumulations of these contaminants (29 CFR
1910.1001(k)(1); 1910.1018(k)(1); 1910.1025(h)(1); 1910.1027(k)(1)).
Spills and sudden releases of material containing cadmium are to be
cleaned up as soon as possible (29 CFR 1910.1027(k)(2); and any spills
of asbestos-containing aqueous solutions or asbestos-containing waste
are to be cleaned up immediately (29 CFR 1910.1001, Appendix F
\[B\](7)).

Sludge contamination in the industrial wastewater treatment plant that
is or has been allowed to dry (and accumulate) can become airborne very
easily and might be a key source of beryllium exposure. Diligent
housekeeping limits the amount of beryllium dust on floors, equipment,
and other surfaces. OSHA visited a ferrous sand casting foundry that
performed a thorough cleaning as one part of a successful effort to
reduce exposure throughout the facility. Initially, general area samples
indicated that the background respirable silica level in the casting
cleaning department was 63 µg/m^3^. \[An employee who spent eight hours
in the area might experience this level of silica exposure by simply
breathing the air. If the employee also performed work that generated
silica dust, exposure from that source would be in addition to the 63
µg/m^3^ back ground level.\] Although the foundry made no physical
changes in the casting cleaning department, walls and dust accumulation
points in the area were vacuumed and washed. After the foundry-wide dust
control efforts, no silica was detected in the casting cleaning
department air and respirable dust levels were 60 to 80 percent lower
than the original level of 1.4 mg/m^3^ (OSHA SEP Inspection Report
303207518). This example demonstrates the extent to which worker
exposure results can be influenced by accumulated dust from poor
housekeeping practices.

Beryllium particles will not become airborne as readily when damp as
when they are dry. Wastewater treatment workers can limit their
exposures to beryllium by cleaning up spilled sludge while it is still
damp. The material should be contained or removed so that it does not
become a source of exposure when it dries. When wastewater treatment
workers encounter dry sludge residue, they can add moisture to help
minimize the release of dust. The moisture can be in the form of water
or other suitable substance.

Where dried sludge accumulations are prevalent, control efforts should
start with a professional level cleaning to remove beryllium-containing
sludge residue from rafters, walls, benches, and equipment. Irwin (2003)
reported on a foundry that reduced silica exposure levels in several job
categories from levels two or three times the current PEL to one-half
the PEL or lower. Among other modifications, "the foundry temporarily
shut down while the entire facility was thoroughly vacuumed and power
washed down to remove many years of accumulated crystalline
silica-containing dust." The down time was used to make other
modifications as well, such as completely renovating the sand-handling
system.

***Wastewater Treatment -- Conclusion:*** The median exposure level for
industrial wastewater treatment workers is approximately 0.1 μg/m^3^
therefore no additional controls are required to further reduce the
median exposure level. For those workers with higher exposure levels,
enhanced work practices are preliminarily estimated to achieve an
average exposure reduction of 32 percent; and, significant improvements
in the level of housekeeping through more effective and/or more frequent
cleaning might further reduce exposures by 60 to 80 percent. Either
additional control will reduce the median exposure level of wastewater
treatment workers below 0.1 μg/m^3^. A combination of the two controls
might reduce exposure levels to between 0.1 μg/m^3^ and 0.3 μg/m^3^ for
those wastewater treatment workers with the highest beryllium levels
(e.g., 1.0 μg/m^3^).

**3.3 PRODUCTION SUPPORT**

Table 3-2 shows that the median exposure level for production support
workers is 0.08 μg/m^3^ with a mean of 0.52 μg/m^3^ and a range of 0.02
μg/m^3^ to 22.71 μg/m^3^. These values represent a total of 810
full-shift PBZ total beryllium levels reported for workers categorized
in production support work groups. These workers include those involved
with (1) on-site scrap recycling (beryllium and copper); (2) maintenance
(production equipment, furnaces and furnace tools, molds and dies); (3)
research and development (R&D); and (4) quality assurance/quality
control/inspection (QA/QC/inspection).

The median exposure levels for all four work groups included in scrap
recycling exceed the lowest proposed PEL option of 0.1 μg/m^3^. The
median levels for these groups include 0.17 μg/m^3^ for the inventory
control center; 0.30 μg/m^3^ for resource recovery; 0.43 μg/m^3^ for
scrap reclamation; and 0.44 μg/m^3^ for leaching. The median exposure
levels for two of the three maintenance work groups also exceed 0.1
μg/m^3^. These groups include workers that maintain/service production
equipment (median exposure level of 0.11 μg/m^3^) and those that
rebuild/repair furnaces and the associated tools (median exposure level
of 0.53 μg/m^3^). Workers maintaining/repairing dies and casting molds
have a median exposure level of 0.05 μg/m^3^ as do the R&D and
QA/QC/inspection workers. Table 3-2 also shows that all workers included
in the production support job category have maximum exposure levels that
exceed 2 μg/m^3^. Maximum exposure levels exceeding 10 μg/m^3^ are
associated with QA/QC/inspection (13.72 μg/m^3^), rebuilding/repairing
furnaces and furnace tools (14.62 μg/m^3^), recycling/leaching (16.38
μg/m^3^), and maintaining/servicing process equipment (22.71 μg/m^3^).

As shown in Table 3-3, 58 percent of the full-shift PBZ total beryllium
exposure levels for workers classified in the production support job
category are less than or equal to the lowest proposed PEL option of 0.1
μg/m^3^. Forty-two percent of the exposure levels are greater than 0.1
μg/m^3^, 27 percent of the exposure levels are greater than 0.2 μg/m^3^,
and 10 percent of the exposure levels exceed 1 μg/m^3^.

***Scrap Recycling -- Inventory Control Center (ICC):*** The inventory
control center is located in a separate building and houses all the
beryllium alloy scrap material received internally and externally (from
Brush Wellman customers). Incoming containers of alloy scrap are
visually inspected and inventoried. Workers sort and identify the type
of scrap received at a partially enclosed and ventilated inspection
table; however, not all alloy scrap is physically handled and inspected.
These workers also operate powered industrial lift trucks and physically
retrieve alloy scrap generated by on-site operations. Worker exposure is
likely associated with the physical manipulation of contaminated scrap
(e.g., during inspection) and the high exposure jobs that ICC workers
come into contact with when they retrieve scrap alloy from on-site
operations.

***Inventory Control Center -- Additional Controls:*** As shown in Table
3-2, the median exposure result for inventory control workers is 0.17
µg/m^3^. Table 3-3 indicates that 19 percent of the full-shift PBZ total
beryllium exposure levels for ICC workers are less than or equal to the
lowest proposed PEL option of 0.1 μg/m^3^. Eighty-one percent of the
exposure levels are greater than 0.1 μg/m^3^, 37 percent of the exposure
levels are greater than 0.2 μg/m^3^, and six percent of the exposure
levels exceed 1 μg/m^3^. Additional controls will be required to reduce
operator exposures. Based on the available information, these additional
controls include:

-   Enhancing the housekeeping program to reduce the level of
    contamination and migration within the workplace. Reportedly, the
    facility did not have a well-documented and enforced housekeeping
    schedule in 1999. As previously discussed (wastewater treatment
    workers), significant improvements in the level of housekeeping
    through more effective and/or more frequent cleaning might further
    reduce exposures by 60 to 80 percent.

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-   Covering containers of dusty scrap (such as slab mill chips)
    especially during material handling activities.

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-   Using industrial lift trucks equipped with properly enclosed,
    sealed, and ventilated operator cabs (i.e., no leaks, positive
    pressure, and effective air filtration). Direct reading instruments
    show that fine particle (0.3 μm size) concentrations inside the
    operator cab can be reduced by an average of 96 percent when cabs
    are clean, sealed (effective door gaskets and no cracks or holes),
    and have a properly designed, installed, and maintained filtration
    and pressurization system (Cecala et al., 2005). With two full-shift
    area samples and direct-reading measurements with real-time
    light-scattering aerosol monitors, NIOSH investigators reported
    respirable dust exposure reductions of 97 and 98 percent,
    respectively, inside a modified ballast regulator cab (NIOSH, 2001).

Since the 1999 baseline exposure monitoring, housekeeping has been
improved in the ICC area. Wet floor sweepers are used to clean the
floors on a daily basis to reduce the level of dust generated by
material handling activities (i.e., fork truck traffic) and containers
of dusty scrap are kept covered.

***Inventory Control Center -- Conclusion:*** Covering containers of
dusty scrap and enhanced housekeeping might substantially reduce the
level of dustiness in the ICC work area and achieve a median exposure
level comparable to or less than the lowest proposed PEL option of 0.1
µg/m^3^. These controls together with the use of properly enclosed,
sealed, and ventilated lift trucks might reduce the exposures of all ICC
workers below 0.1 µg/m^3^.

***Scrap Recycling -- Scrap Reclamation:*** Scrap reclamation workers
receive high beryllium scrap chips (from internal and external sources)
that are degreased, magnetically screened for iron removal, sorted,
inspected, and containerized for reuse internally. Existing exposure
controls include the use of a walk-in exhaust hood for degreasing, an
enclosed magnetic separator, an enclosed/ventilated glove box for
sorting and inspecting processed scrap, and engineered drum breaks
(designed internally) that capture residual material released during
drum connection and disconnection to/from the process. Worker exposures
might be primarily associated with opening (cracking) containers and
connecting/disconnecting containers (make-break connections) to/from the
process (e.g., during drum filling operations). During drum filling,
leakage can occur at material entry connection points presumably due to
alignment problems and/or the design of the valve system. Operator skill
and/or work practice variability appear to play a role in the
misalignment issues. Other sources of exposure include sample collection
(i.e., at each step in the process a sample is collected for a quality
check); and nearby high exposure operations (i.e., the pebble plant and
vacuum casting).

***Scrap Reclamation -- Additional Controls:*** As shown in Table 3-2,
the median exposure level for scrap reclamation workers is 0.43 μg/m^3^.
Table 3-3 indicates that 11 percent of the full-shift PBZ total
beryllium exposure levels for scrap reclamation workers are less than or
equal to the lowest proposed PEL option of 0.1 μg/m^3^. Eighty-nine
percent of the exposure levels are greater than 0.1 μg/m^3^, 81 percent
of the exposure levels are greater than 0.2 μg/m^3^, and 31 percent of
the exposure levels exceed 1 μg/m^3^. Additional controls are required
to reduce worker exposure. Based on the available information, these
additional controls include:

-   Improving work practices through operator training, work practice
    modifications, and/or better enforcement/supervision to minimize
    potential exposures associated with opening/sealing containers and
    material transfer operations (make-break connections). Reportedly,
    there is a proper sequence of events that must occur during
    make-break operations (Kent, 2005). Workers might not realize that
    following a certain sequence of steps makes a difference in their
    beryllium exposure. As discussed previously, work practice
    improvements might be expected to achieve an average exposure
    reduction of 32 percent when work practice issues primarily
    contribute to operator exposure.

-   Installing a fail-safe drum break system to prevent fugitive
    emissions at container connection points during material transfer
    operations or fully enclosing the engineered drum breaks. Potential
    problems with the existing drum break system also include material
    retained inside valves and tubing, perhaps due to surface roughness;
    and, the inability to see or otherwise determine if all the material
    transfer has occurred.

> Pharmaceutical quality packing head systems are used for
> filling/weighing operations involving high-hazard powders. Packing
> head systems provide a sealed connection between the filling device
> and the container for dust-free transfer of product. Vented and
> extraction type sealing heads are available for applications where
> container pressure must be avoided. Packing heads used in conjunction
> with laminar flow containment booths (containment isolator) further
> ensure operator safety during container filling. Or, as an
> alternative, containment booths can be used as secondary containment
> between two vessels during make-break operations. Typical applications
> for powder containment booths include large scale dispensing,
> weighing, and product sampling. (Absolute Control Systems, Inc., 2004;
> Hosokawa Micron Group, 2005). Additionally, customized double
> butterfly valves can be fabricated for applications where gas and
> dust-tight dosing and discharging of bulk materials is required in
> addition to stringent emission and leakage. Reportedly, pharmaceutical
> quality high containment powder and granule handling systems can
> achieve dust control exposure levels of 0.1 µg/m^3^ or less (Hosokawa
> Micron Group, 2005).

[]{.mark}

-   Eliminating or reducing the exposures associated with sample
    collection through engineering enhancements. A beryllium alloy plant
    used five automatic Isolok™ solid material samplers in their
    calcining and reduction operation to sample fresh beryllium oxide
    from the calciner and storage bins, flue dust, blended material, and
    finished product (four percent beryllium-copper alloy). The
    pneumatic samplers operate on a positive displacement, closed
    collection principle. A fixed amount of solid sample is withdrawn
    with each stroke of the single moving plunger. The extracted sample
    falls into a closed sample container (plastic collection bottle)
    that is manually removed on a periodic basis and carried to the
    laboratory for analysis. A new collection container is manually
    attached to the sampler for the next sampling cycle. In addition to
    the automatic samplers, the plant also utilized a negative pressure
    isolation/enclosure chamber for the beryllium oxide storage bin and
    the calciner operation. To evaluate the solid material sampling
    operations, NIOSH investigators collected area air samples over five
    shifts at 13 locations in the calcining and reduction area. The
    average beryllium concentrations ranged from 0.1 µg/m^3^ to 1.06
    µg/m^3^. NIOSH investigators concluded that the design of the
    automatic solid material samplers significantly contributed to low
    worker exposures (NIOSH, 1982; 1983). Further reductions in exposure
    can be achieved by incorporating Isolok solid material samplers
    with pharmaceutical quality glove boxes to control exposures
    associated with removing and capping sample collection containers
    (Sentry Equipment Corporation, 2005).

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-   Enhancing the exhaust ventilation in the scrap reclamation area. The
    facility enhanced the ventilation throughout the operation by
    doubling the exhaust flow. Information regarding the exposure
    reduction that was achieved with this engineering modification is
    not available to ERG. However, Kent suggests that ventilation
    enhancements alone might achieve an exposure reduction of 20 to 50
    percent. Enhanced engineering and work practice controls together
    typically might be expected to reduce exposure by two to three times
    (Kent, 2005).

\[During the 1999 baseline exposure monitoring, the scrap reclamation
operation included an additional step that has since been
decommissioned. This step was termed the float sink operation. After
scrap chips were degreased and magnetically screened, they were
processed in an enclosed tank of bromochloromethane. Recovered beryllium
floated to the surface of the bath, was skimmed off the top, and then
dried on a drying tray in an exhaust hood. Information regarding the
potential impact that this operation had on worker exposure is not
available to ERG.\]

***Scrap Reclamation -- Conclusion:*** Based on the available
information, ERG preliminarily estimates that an exposure reduction of
50 percent (resulting in a median exposure level of approximately 0.22
μg/m^3^) might be achieved through a combination of ventilation and work
practice improvements in the scrap reclamation area. Additional
reductions in exposure are expected with engineering improvements during
sample collection and material transfer operations. Implementing the use
of automatic solid material samplers (or other equally effective
engineering intervention) either individually or in combination with
high containment glove boxes is expected to significantly reduce
operator exposures associated with sampling. Pharmaceutical quality
powder handling, transfer, and filling systems are likely to achieve a
greater level of exposure control than enhanced work practices alone and
reportedly can achieve dust control levels of 0.1 µg/m^3^ or less. ERG
therefore finds that a median exposure level comparable to the lowest
proposed PEL option might be achieved through the use of enhanced
ventilation and work practices, pharmaceutical quality high containment
powder handling/transfer systems, and solid material samplers equipped
with glove boxes.

***Scrap Recycling -- Leaching:*** Leaching is a sensitive chemical
cleaning process for scrap beryllium chips and powders that uses acids
to remove contaminants that cannot be physically or magnetically
separated from the scrap material. The cleaning occurs in enclosed and
ventilated tanks. After leaching there is a screening (sizing)/washing
step (that takes place inside an exhaust hood) where workers manually
screen the (wet) material with rakes while standing outside the hood.
Screened material is dried, transported to a hopper, and then
containerized in drums. Worker exposure is likely to be primarily
associated with material loading/unloading at the beginning and end of
the process and perhaps with manual screening/sizing (i.e., the hood
and/or work practices). Product loading and unloading is usually
performed with engineered drum breaks under LEV. The drum breaks have
different designs depending on whether they have been designed for chip
or powder applications. Chip drum breaks are prone to leakage due to
misalignment as noted in scrap reclamation. Powder drum breaks are prone
to leakage when the receiving container is removed from the material
transfer feed pipe. Although the connection point has local exhaust
ventilation, operators need to tape the opening to the receiving
container to prevent unnecessary exposure when removing the receiving
container from the transfer feed pipe. Additionally, operator exposure
might be affected by material variability, i.e., scrap material getting
stuck during transfer operations and requiring operator intervention to
dislodge it.

***Leaching -- Additional Controls:*** As shown in Table 3-2, the median
exposure level for leaching is 0.44 μg/m^3^. Table 3-3 indicates that 17
percent of the full-shift PBZ total beryllium exposure levels for
leaching workers are less than or equal to the lowest proposed PEL
option of 0.1 μg/m^3^. Eighty-three percent of the exposure levels are
greater than 0.1 μg/m^3^ and 0.2 μg/m^3^ (i.e., there are no exposure
levels greater than 0.1 μg/m^3^ and less than or equal to 0.2 μg/m^3^),
and 33 percent of the exposure levels exceed 1 μg/m^3^. Additional
controls are required to reduce worker exposure. Based on the available
information, these additional controls include:

-   Improving work practices through operator training, work practice
    modifications, and/or better enforcement/supervision to minimize
    potential exposures associated with raking (screening/washing step)
    and material transfer operations (e.g., make-break connections).
    Reportedly, there is a proper sequence of events that must occur
    during make-break operations. Workers might not realize that
    following a certain sequence of steps makes a difference in their
    beryllium exposure. As discussed previously, work practice
    improvements might be expected to achieve an average exposure
    reduction of 32 percent when work practice issues primarily
    contribute to operator exposure.

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-   Installing a fail-safe drum break system to prevent fugitive
    emissions at container connection points during material transfer
    operations or fully enclosing the engineered drum breaks. Potential
    problems with the existing drum break system also include material
    retained inside valves and tubing, perhaps due to surface roughness;
    and, the inability to see or otherwise determine if all the material
    transfer has occurred.

> Pharmaceutical quality packing head systems are used for
> filling/weighing operations involving high-hazard powders. Packing
> head systems provide a sealed connection between the filling device
> and the container for dust-free transfer of product. Vented and
> extraction type sealing heads are available for applications where
> container pressure must be avoided. Packing heads used in conjunction
> with laminar flow containment booths (containment isolator) further
> ensure operator safety during container filling. Or, as an
> alternative, containment booths can be used as secondary containment
> between two vessels during make-break operations. Typical applications
> for powder containment booths include large scale dispensing,
> weighing, and product sampling. (Absolute Control Systems, Inc., 2004;
> Hosokawa Micron Group, 2005). Additionally, customized double
> butterfly valves can be fabricated for applications where gas and
> dust-tight dosing and discharging of bulk materials is required in
> addition to stringent emission and leakage. Reportedly, pharmaceutical
> quality high containment powder and granule handling systems achieve
> dust control exposure levels of 0.1 µg/m^3^ or less (Hosokawa Micron
> Group, 2005).

-   Investigating the adequacy of the LEV for screening/washing. An LEV
    system designed in accordance with ACGIH criteria would be expected
    to significantly reduce worker exposures associated with the
    screening/washing step should the existing system be found to be
    less than optimal.

***Leaching -- Conclusion:*** Work practice improvements are estimated
to achieve an average exposure reduction of 32 percent resulting in a
median exposure level of approximately 0.3 μg/m^3^ for those workers
whose exposure is primarily attributed to work practice issues.
Additional reductions in exposure are expected with engineering
improvements during material transfer operations. Pharmaceutical quality
powder handling, transfer and filling systems are likely to achieve a
greater level of exposure control than enhanced work practices alone and
reportedly can achieve dust control levels of 0.1 µg/m^3^ or less. ERG
therefore finds that a median exposure level comparable to the lowest
proposed PEL option might be achieved through the use of enhanced work
practices and LEV, and pharmaceutical quality high containment powder
handling/transfer systems.

***Scrap Recycling -- Resource Recovery:*** Resource recovery operations
involve the recycling of scrap beryllium and copper from drosses and
other waste streams. Drosses and collector fines from alloy melting and
casting operations are received in 55-gallon drums, opened in an exhaust
hood/drum tilter, loaded into a ventilated elevator and transferred to
an enclosed and ventilated dross mill where the material is processed
into a wet slurry of beryllium and copper. From the dross mill, the wet
slurry is transferred through enclosed piping to ventilated slurry tanks
equipped with flip top hatches. In the slurry tanks, pH is adjusted and
chemical additions are made. Process upsets occurred in the past due to
the exothermic nature of the chemical reactions but are now well
controlled through the use of anti-foaming agents and automated chemical
additions (i.e., acids are now metered in). After chemical processing,
the scrap material is processed in an enclosed centrifuge yielding
semisolids containing beryllium and a liquid decant primarily containing
copper. The semisolids are piped to an enclosed filter press, manually
collected in containers, and then shipped to an off-site location for
additional processing. The liquid decant is piped to copper recovery
operations (electrowinning) located in a separate building. Worker
exposures might be associated primarily with drum unloading and to a
lesser extent with chemical process upsets. During drum unloading, the
LEV inside the hydraulic drum tilter created a significant amount of
turbulence that resulted in excessive beryllium contamination on the
inside of the access door. To avoid significant exposure, workers needed
to open the access door very slowly. The facility corrected this problem
by installing an access hole for a water hose in the door of the drum
tilter. Now the inside of the tilter/hood and the drum are thoroughly
wet down with water before the access door is opened and the empty drum
is removed. ERG preliminarily estimates that this engineering
modification reduced worker exposures by 20 to 50 percent. The impact
that process upsets have on worker exposure is not known. ERG therefore
estimates that process upsets account for at least 10 percent of worker
exposure.

***Resource Recovery -- Additional Controls:*** As indicated in Table
3-2, the median exposure result for resource recovery workers is 0.30
μg/m^3^. Table 3-3 indicates that 11 percent of the full-shift PBZ total
beryllium exposure levels for resource recovery workers are less than or
equal to the lowest proposed PEL option of 0.1 μg/m^3^. Eighty-nine
percent of the exposure levels are greater than 0.1 μg/m^3^, 62 percent
of the exposure levels are greater than 0.2 μg/m^3^, and 26 percent of
the exposure levels exceed 1 μg/m^3^. Additional controls are required
to reduce worker exposure. Based on the available information, these
additional controls might include:

-   Reducing worker exposures associated with drum unloading by
    thoroughly wetting down the inside of the drum tilter/hood and the
    empty drum prior to opening the access door; and,

-   Preventing process upsets through the use of automated chemical
    additions and anti-foaming additives.

\[Some of the higher exposure levels reported for resource recovery
workers in 1999 might have been associated with an unventilated copper
recovery task associated with electrowinning. This operation involved
the plating of scrap copper (potentially contaminated with beryllium)
onto collection plates and the subsequent manual removal of the copper
from the plates by chipping. This operation has since been modified by
plating directly onto a copper plate and eliminating the need to
manually remove recovered copper. Information regarding the exposure
reduction achieved with this modification is not available to ERG.\]

***Resource Recovery -- Conclusion:*** ERG preliminarily estimates that
the exposures of resource recovery operators have been reduced by 20 to
50 percent through the introduction of effective wet control methods
during drum unloading. The use of antifoaming agents and automated
chemical additions has likely further reduced exposures by at least 10
percent. Together these additional controls might reduce median
exposures to the lowest PEL options; i.e., 0.1 μg/m^3^ and 0.2 μg/m^3^.

***Maintenance -- Production Equipment:*** Workers that maintain
production and production-related equipment are exposed to beryllium
when they disturb work surfaces and equipment that are contaminated with
beryllium. The greater the surface contamination, the greater the
potential exposure these workers might receive. Two examples of
production equipment with significant contamination that maintenance
workers must service and repair include the air cleaning devices (e.g.,
the dust collectors) and the furnaces (e.g., the furnace hydraulic
systems). Workers have both portable and central HEPA-filtered
ventilation units with flexible ducts and hoods available for their use
during maintenance activities. Since these units are operator controlled
and adjusted, operator work practices might be a factor in the higher
exposure levels reported for production maintenance workers.
Specifically, workers need to use the LEV and they need to use it
correctly. Additionally, the portable HEPA-filtered ventilation units
are not fireproof and might be problematic for hot work activities such
as welding and grinding.

***Maintenance (production equipment) -- Additional Controls:*** As
shown in Table 3-2, the median exposure level for production equipment
maintenance workers is 0.11 μg/m^3^. Table 3-3 indicates that 47 percent
of the full-shift PBZ total beryllium exposure levels for production
maintenance workers are less than or equal to the lowest proposed PEL
option of 0.1 μg/m^3^. Fifty-three percent of the exposure levels are
greater than 0.1 μg/m^3^, 32 percent of the exposure levels are greater
than 0.2 μg/m ^3^, and 14 percent of the exposure levels exceed 1
μg/m^3^. Additional controls are required to reduce worker exposure.
Based on the available information, these additional controls include:

-   Decontaminating (or enhancing the decontamination of) production
    equipment prior to service or maintenance to remove as much
    contamination as possible (e.g., HEPA vacuuming to remove gross
    surface contamination and then wet wiping).

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-   Improving work practices associated with the use and positioning of
    portable HEPA-filtered ventilation units through operator training,
    work practice modifications, and/or better enforcement/supervision.
    As discussed previously, work practice improvements might be
    expected to achieve an average exposure reduction of 32 percent when
    work practice issues primarily contribute to operator exposure.

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-   Investigating the effectiveness of the LEV. An LEV system designed
    in accordance with ACGIH criteria would be expected to significantly
    reduce worker exposures associated with equipment maintenance should
    the existing system be found to be less than optimal. Possible
    improvements might include changing or modifying hood design and/or
    increasing exhaust flow.

***Maintenance (production equipment) -- Conclusion:*** Work practice
enhancements that incorporate effective equipment decontamination and
the appropriate use of HEPA-filtered ventilation units might achieve an
exposure reduction of 32 percent resulting in a median exposure level
below the lowest proposed PEL option of 0.1 µg/m^3^.

***Maintenance -- Furnace and Tools:*** The frequency with which
furnaces require rebuilding can vary from two weeks to two months and
depends on the type of furnace and the number of heat cycles it has been
operated. For example, in the New Cast Shop, furnaces require rebuilding
about every 30 to 60-heat cycles and may operate for four heat cycles
per day. Because of the approximately 40 furnaces located at the Brush
Wellman Elmore, Ohio facility, furnace rebuilding is done on a daily
basis. Although some repairs are done in place, most furnaces are not
rebuilt in place. For repair-in-place, maintenance workers rely on the
furnace LEV for exposure control. All other furnaces are moved to a
segregated rebuilding control room equipped with several bays for
working on multiple furnaces simultaneously. Depending on the type and
size of the furnace, the refractory lining may either be hydraulically
extracted or removed using manual demolition methods (i.e.,
jackhammers). For example, large induction furnace linings (that are
about eight feet long and five feet in diameter) are removed by
hydraulically extracting the lining using a "pusher." The lining is then
transferred to the furnace rebuild room where maintenance workers
(furnace rebuilders) equipped with appropriate personal protective
equipment and respirators use jackhammers to break the lining into
smaller pieces. Occasionally large linings crack inside the furnace
during removal. When this occurs, furnace rebuilders may need to enter
the furnace to remove the residual lining with jackhammers. Other large
furnaces, such as the Whiting arc furnace, do not have a quick lining
removal feature. Workers must enter this furnace and manually demolish
the refractory lining. The linings in smaller furnaces are approximately
three to four feet deep and are not hydraulically extracted. Furnace
rebuilders working from above (i.e., the top of the furnace) manually
break up smaller linings.

The furnace rebuild room is ventilated (about one air change per minute)
and maintenance workers have high exhaust flow LEV hose drops
(approximately 10,000 cfm) and HEPA vacuums (central and portable
diesel-powered) available for use during rebuilding activities.
Additionally, wet methods are reportedly used during demolition
activities. Worker exposures are primarily associated with two
activities: (1) cleaning contaminated furnaces prior to rebuilding and
(2) the mechanical generation of beryllium aerosols during repair and
reconditioning activities (e.g., the manual demolition of furnace
linings). Demolition activities probably contribute most to worker
exposures (about 90 percent) whereas cleaning activities may account for
about 10 percent of total exposure. In the past, workers reportedly were
not properly decontaminating furnaces prior to rebuilding.

In addition to furnaces, maintenance workers must also rebuild
contaminated furnace tools. These tools are fabricated in-house and
include furnace rub bars and dross rakes that are ten to twelve feet in
length. Maintenance workers cut off the contaminated sections of these
tools and weld new sections on. Cut-off saws, grinders, and welders are
used to repair these tools. Workers utilize operator-positioned LEV hose
drops (some with hoods and some without) during these repair activities.
Other exposure controls available to furnace maintenance workers include
the use of HEPA vacuum systems (central and portable) and wet methods
for cleaning work areas. Worker exposure during furnace tool maintenance
might be related to inappropriate work practices. For furnace tools, the
appropriate work practice includes following the established standard
operating procedure (i.e., cleaning off the end of the tool prior to
welding and welding inside an exhaust hood). Worker exposure can be
minimized if tools are cut and repaired following established work
practices.

***Maintenance (furnace and tools) -- Additional Controls:*** As shown
in Table 3-2, the median exposure level for furnace and tool maintenance
workers is 0.53 μg/m^3^. Table 3-3 indicates that ten percent of the
full-shift PBZ total beryllium exposure levels for furnace and tool
repair workers are less than or equal to the lowest proposed PEL option
of 0.1 μg/m^3^. Ninety percent of the exposure levels are greater than
0.1 μg/m^3^, 81 percent of the exposure levels are greater than 0.2
μg/m^3^, and 33 percent of the exposure levels exceed 1 μg/m^3^.
Additional controls are required to reduce worker exposure. Based on the
available information, these additional controls include:

-   Improving work practices through operator training, work practice
    modifications, and/or better enforcement/supervision. For example,
    decontaminating (or enhancing the decontamination of) furnaces and
    tools prior to service or maintenance to remove as much
    contamination as possible (e.g., HEPA vacuuming to remove gross
    surface contamination and then wet wiping). As discussed previously,
    work practice improvements might be expected to achieve an average
    exposure reduction of 32 percent when work practice issues primarily
    contribute to operator exposure.

-   Cutting up and throwing out (or reclaiming) used furnace tools and
    making or buying new furnace tools.

-   Purchasing new furnaces (when needed) that feature extractable
    liners and/or retrofitting existing furnaces (if possible). Although
    this design feature does not completely eliminate the need for
    manual demolition, it might reduce exposures by up to one third when
    compared to refractory lining removal by 100 percent manual
    demolition (Kent, 2005). However, ERG is uncertain as to the overall
    exposure reduction that might be achieved with extractable linings
    because this feature appears to be furnace-specific; i.e., not all
    furnace types can be purchased or retrofitted with quick lining
    removal. Of the approximately 40 furnaces at the Brush Wellman
    Elmore facility, quick lining removal is utilized on four large
    induction furnaces.

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-   Using jackhammers equipped with a controlled water spray at the
    chisel point. Various studies have reported significant respirable
    quartz exposure reductions ranging from 70 to 98 percent when
    jackhammering with water-supplied jackhammers as compared to dry
    jackhammering (Zalk, 2000; NIOSH, 2003; Williams and Sam, 1999).
    Based on these findings, an additional exposure reduction might be
    possible with the use of water-supplied jackhammers during furnace
    rebuilding. However, ERG is uncertain as to whether exposure
    reductions ranging from 70 to 98 percent might be achieved because
    the lowest median respirable quartz reading reported during wet
    jackhammering is 30 μg/m^3^ (see Zalk, 2000). Therefore, using
    Kent's rule of thumb, ERG estimates that engineering control
    improvements, such as wet jackhammering, might be expected to reduce
    beryllium exposures by 20 to 50 percent. Enhanced engineering and
    work practice controls together typically might be expected to
    reduce exposures by two to three times (Kent, 2005).

> Zalk (2000) conducted a pilot study of a prototype water-supplied
> jackhammer and found that the modified tool resulted in significant
> respirable quartz exposure reductions when compared with dry
> jackhammering. The median reading obtained for two 90-pound jackhammer
> operators (two samples per operator) performing impact drilling
> outside in dry conditions was 300 μg/m^3^, compared with a median of
> less than the limit of detection of 70 μg/m^3^ obtained during wet
> jackhammering. This is an exposure reduction of at least 77 percent.
> An exposure reduction of 98 percent was obtained for workers
> performing wet jackhammering indoors in dry conditions. The median
> respirable quartz reading under dry conditions was 1,300 μg/m^3^,
> while wet methods resulted in a median of 30 μg/m^3^.[^2]
>
> NIOSH (2003) investigated a water spray dust control used by workers
> breaking concrete with 60 and 90-pound jackhammers. Using both a
> direct-reading (real-time) instrument and a high flow cyclone with
> filter media, NIOSH collected 10-minute readings with and without the
> water spray activated. Compared to uncontrolled concrete pavement
> breaking, PBZ respirable dust concentrations were between 72 and 90
> percent lower when the water spray was used. Specifically, the
> geometric mean for the filter air samples was reduced from 2.06
> mg/m^3^ with no controls to 0.55 mg/m^3^ with the water spray; and,
> for the real-time samples, the geometric mean was reduced from
> approximately 0.74 mg/m^3^ with no controls to about 0.08 mg/m^3^ with
> the water spray.
>
> Similarly, Williams and Sam (1999) report that a hand-held pneumatic
> chipper equipped with a water spray nozzle reduced worker exposure to
> respirable crystalline silica by 70 percent during concrete truck drum
> cleaning. Workers periodically spray the interior surface of the drum
> and have a continuous water spray directed at the chisel point during
> chipping. The water flow rate is operator adjusted and is described as
> a controlled mist that does not generate excess water (Sam, 2004).

***Maintenance (furnace and tools) -- Conclusion:*** Enhanced work
practices associated with equipment decontamination and tool maintenance
might result in an average exposure reduction of 32 percent where worker
exposures are primarily associated with work practice issues. \[Cutting
up and throwing out or reclaiming used furnace tools and making or
buying new furnace tools would be expected to significantly reduce
worker exposure associated with furnace tool maintenance.\] The use of
water-supplied jackhammers might further reduce worker exposure
associated with demolition activities by 20 to 50 percent. Together,
enhanced work practices and wet jackhammering may reduce the median
exposure of furnace maintenance workers by two to three times to
approximately 0.2 μg/m^3^. Additionally, furnaces should be purchased
and/or retrofitted with extractable linings, if possible. This feature
will further reduce worker exposures associated with furnace rebuilding.
However, an estimate of the overall exposure reduction that might be
achieved with extractable linings is problematic because not all furnace
types can be purchased or retrofitted with quick lining removal. To
reduce the median exposure level of furnace maintenance workers to the
lowest proposed PEL option, respiratory protection will be necessary.

**3.4** **COLD WORK**

Table 3-2 shows that the median exposure level for workers engaged in
cold operations is 0.08 μg/m^3^ with a mean of 0.32 μg/m^3^ and a range
of 0.04 μg/m^3^ to 24.89 μg/m^3^. These values represent a total of 606
full-shift PBZ total beryllium exposure levels reported for workers
categorized in cold operation work groups. These workers include those
involved in rolling, straightening, drawing, machining, and mix make-up.
Mix make-up operators prepare and charge furnaces with alloy melting
mixes that consist of scrap and prepared ingot.

The median exposure levels for rolling, straightening, and drawing do
not exceed the lowest proposed PEL option of 0.1 μg/m^3^. The median
exposure levels for these work groups are 0.05 μg/m^3^ for rolling and
drawing, and 0.06 μg/m^3^ for straightening. The median exposure levels
for mix make-up and the machining of billets and high content beryllium
exceed 0.1 μg/m^3^. The median levels for these groups are 0.24 μg/m^3^
for mix make-up, 0.13 μg/m^3^ for machining billets, and 0.17 μg/m^3^
for machining high content beryllium. Table 3-2 also shows that all
workers included in the cold work job category, except those involved in
drawing, have maximum exposure levels that exceed 1 μg/m^3^. The highest
maximum exposure levels are associated with machining operations and
range from 16.00 μg/m^3^ (alloys) to 24.89 μg/m^3^ (high content
beryllium).

As indicated in Table 3-3, 58 percent of the full-shift PBZ total
beryllium levels for workers classified in the cold work job category
are less than or equal to the lowest proposed PEL option of 0.1 μg/m^3^.
Forty-two percent of the exposure levels are greater than 0.1 μg/m^3^,
23 percent of the exposure levels are greater than 0.2 μg/m^3^, and five
percent of the levels exceed 1 μg/m^3^.

***Mix make-up (Old Cast Shop):*** Mix makeup operators prepare and
charge furnaces with alloy melting mixes. This activity involves the use
of material handling equipment such as industrial lift trucks and the
transfer of bulk material between charge tubs and furnaces. Furnace
charges are prepared in ventilated mix stations and loaded into tubs
where they are charged in the furnaces through a pneumatically operated
cart (Kent et al, 2001). Mix make-up operators work in a wide-open area
in close proximity to the alloy melting and casting operations. A
partial enclosure equipped with a slot hood is used to control exposure
at the mix station in the Old Cast Shop (floor weigh-scale location). In
the New Cast Shop, mix make-up is incorporated into the furnace
operator's job and a sub-grade ventilated pit is used as a mixing
station. Other exposure controls for this activity include the use of
HEPA vacuum systems (central and portable) and wet methods for workplace
cleaning. Worker exposure is primarily associated with adjacent
contaminant-producing operations (i.e., melting and casting) and the
handling of dusty scrap in the Old Cast Shop. \[The New Cast Shop uses
master alloy, pure copper rod, and very clean scrap for furnace
charges.\] The exposure breakdown between nearby melting and casting
operations and the handling of dusty scrap is not known. Based on
discussions with industry experts, ERG estimates that nearby melting and
casting operations might account for up to 70 percent of mix make-up
operator exposure.

***Mix-Makeup -- Additional Controls:*** As indicated in Table 3-2, the
median exposure level of mix make-up workers is 0.24 μg/m^3^. Table 3-3
indicates that 27 percent of the full-shift PBZ total beryllium exposure
levels for mix make-up operators are less than or equal to the lowest
proposed PEL option of 0.1 μg/m^3^. Seventy-three percent of the
exposure levels are greater than 0.1 μg/m^3^, 55 percent of the exposure
levels are greater than 0.2 μg/m^3^, and 12 percent of the levels exceed
1 μg/m^3^. Additional controls are required to reduce worker exposure.
Based on the available information, these additional controls include:

-   Enhancing mix make-up work practices through operator training, work
    practice modifications, and/or better enforcement/supervision. For
    example, ensuring that charge carts containing dusty scrap in the
    Old Cast Shop are covered and cleaning dusty scrap (e.g. scrap
    furnace ingots) before using it in furnace charges. Controlled
    cleaning of dusty scrap will reduce mix make-up operators' exposures
    when preparing furnace charges. Note that any wet methods employed
    for cleaning would need to be followed by a thorough drying step to
    eliminate moisture prior to charging into the melting furnace. As
    discussed previously, work practice improvements might be expected
    to achieve an average exposure reduction of 32 percent when work
    practice issues primarily contribute to operator exposure.

-   Reducing the level of exposure associated with the adjacent melting
    and casting operations (e.g., isolating furnace decks and dross
    handling will minimize the distribution of beryllium contamination
    in adjacent operations such as mix make-up).

***Mix Make-up -- Conclusion:*** Enhanced work practices and procedures
addressing the use of charge cart covers and controlled cleaning of
dusty scrap might achieve an exposure reduction of 32 percent resulting
in a median exposure level of 0.16 μg/m^3^ for mix make-up workers.
Additional reductions in exposure would be expected if exposures
associated with the adjacent melting and casting operations could be
reduced.

***Machining:*** Machining involves the use of metal forming equipment
to machine and/or fabricate beryllium-containing parts or shapes.
Machining may be done manually or with the use of precision computer
numerically controlled (CNC) equipment. Activities included with
machining might include milling, turning, cutting, grinding, drilling,
deburring, sawing, swaging, slitting, sanding, and tool grinding and
other forms of tool maintenance. Machining might be conducted with no
engineering controls, wet (with flood coolant) or dry, with or without
LEV, and with or without equipment enclosures. The controls utilized
depend on the beryllium content of the parts or shapes being machined
and the type of machining being performed (i.e., beryllium particle size
and generation rate). For example, high content beryllium is machined
wet or dry, typically with LEV (low volume/high velocity (LVHV) source
capture). If machining is performed wet, the machining equipment might
also be enclosed to contain the coolant. Beryllium alloys are typically
machined wet, but without LEV or machine enclosures. Worker exposures
are associated with numerous factors including working in close
proximity to high exposure activities (melting and casting); work
practice issues such as improper positioning of LVHV source capture
exhaust ducts; opening machine enclosures during machining and/or too
soon after machining; inadequate management/containment of
beryllium-contaminated coolant, and lack of LEV and/or machine
enclosures.

As previously stated, higher median exposure levels are associated with
the machining of alloy billets (0.13 µg/m^3^) and high content beryllium
parts and shapes (0.17 µg/m^3^). Billets are rough alloy castings that
are machined to smooth out the surface of the casting and remove
imperfections. Table 3-3 indicates that 42 percent of the exposure
levels for workers machining alloy billets are less than or equal to the
lowest proposed PEL option of 0.1 μg/m^3^. Fifty-eight percent of the
exposure levels are greater than 0.1 μg/m^3^, 26 percent of the exposure
levels are greater than 0.2 μg/m^3^, and approximately seven percent of
the exposure levels exceed 1 μg/m^3^. Workers machining alloy billets
work in close proximity to the melting and casting operations and their
exposures might be predominately associated with this co-location issue.
Table 3-3 also shows that 41 percent of the exposure levels reported for
workers machining high content beryllium are less than or equal to the
lowest proposed PEL option of 0.1 μg/m^3^. Fifty-nine percent of the
exposure levels are greater than 0.1 μg/m^3^, 41 percent of the exposure
levels are greater than 0.2 μg/m^3^, and ten percent of the exposure
levels are greater than 1 μg/m^3^.

***Machining -- Additional Controls:*** Additional controls are required
to further reduce machining exposures. Based on the available
information, these additional controls include the following:

-   Reducing co-location exposures by isolating alloy machining
    operations (billet preparation) from nearby high exposure activities
    associated with melting and casting. It might be possible to build a
    floor to ceiling wall to isolate the alloy machining operations. The
    use of overhead cranes will be problematic and the building and
    processes will likely have to be redesigned. Information regarding
    the exposure reduction that might be achieved by isolating billet
    preparation from melting and casting is not known. Based on
    discussions with industry experts, ERG estimates that exposure
    levels of 0.2 μg/m^3^ might be achievable (Corbett, 2004).

-   Improving work practices associated with machining through operator
    training, work practice modifications, and/or better
    enforcement/supervision (e.g., proper positioning of source capture
    exhaust ducts and coolant management).

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-   Adding total machine enclosures to wet machining operations. In an
    investigation of exposure to cobalt during wet grinding of hard
    metal blades, Linnainmaa (1995) observed that full-shift PBZ
    exposures were reduced 50 to 91 percent when two semiautomatic
    grinding machines with splash guards (minimally enclosed) were fully
    enclosed. Exposures before enclosing the machines ranged from six to
    33 μg/m^3^ (n = 21 samples); after fully enclosing the grinding
    machines exposures were 3 μg/m^3^ (n = 3 samples). ERG is uncertain
    as to the overall beryllium exposure reduction that might be
    achieved with total machine enclosures because the number of samples
    collected after fully enclosing the grinding machines is small in
    comparison to before and the exposure level achieved is greater than
    the PEL options. ERG therefore estimates a maximum beryllium
    exposure reduction of 50 percent through the addition of total
    machine enclosures.

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-   Adding LEV or enhancing existing LEV.

-   Fully enclosing and ventilating machining operations. As previously
    discussed in ERG's commentary on the precision machining sector, the
    median full-shift PBZ exposure level for machinists at ERG Site 1 is
    less than 0.02 µg/m^3^ (limit of detection) with a mean of 0.035
    µg/m^3^ and a range of less than 0.02 µg/m^3^ (limit of detection)
    to 0.11 µg/m^3^. All machining operations at ERG Site 1 are fully
    enclosed, sealed, and ventilated.

-   Interlocking the doors of fully enclosed and ventilated machine
    enclosures with the machining cycle such that the enclosure cannot
    be opened during the machining cycle and the operator has to wait a
    designated period of time at the completion of the cycle (e.g., one
    to two minutes to allow for sufficient exhausting of the enclosure)
    before the door can be opened to retrieve the machined part.

For additional discussion of the controls associated with machining, the
reader is referred to ERG's commentary on the precision machining
sector.

***Machining -- Conclusion:*** Nearly all workers whose exposures are
primarily associated with machining (as opposed to working in close
proximity to a high exposure activity) can achieve beryllium exposure
levels of 0.1 μg/m^3^ or less through a combination of engineering and
work practice controls. Reductions in exposure can be achieved through
the implementation or modification and enhancement of LEV, machine
enclosures, and/or work practices. This finding is based on ERG's
commentary on the precision machining sector. For those machining
workers whose exposure is primarily due to working in close proximity to
the melting and casting area, isolating machining activities from
melting and casting operations is estimated to result in exposure levels
of approximately 0.2 µg/m^3^. Additional reductions in exposure
comparable to the lowest proposed PEL option are expected through the
use of engineering controls such as total machine enclosures.

**3.5 HOT WORK**

As shown in Table 3-2, the median exposure level for workers engaged in
hot-type operations is 0.06 μg/m^3^ with a mean of 0.12 μg/m^3^ and a
range of 0.01 μg/m^3^ to 2.21 μg/m^3^. These values represent a total of
297 full-shift PBZ total beryllium levels reported for workers
categorized in hot work work groups. These workers include those
involved with hot forming (hot rolling and extruding), annealing (heat
treatment in gas-fired furnaces), and welding. Pickling and vapor
degreasing work groups are also included in this job category because
these operations are conducted at elevated process temperatures.

The median exposure levels for four out of the five work groups included
in this job category are less than the lowest proposed PEL option of 0.1
μg/m^3^. These groups include pickling and degreasing, both with a
median exposure level of 0.05 μg/m^3^; hot rolling and extrusion, with a
median exposure level of 0.06 μg/m^3^; and annealing, with a median
exposure level of 0.08 μg/m^3^. Welding is the only work group included
in the hot work job category with a median exposure level greater than
0.1 μg/m^3^. The median exposure level for welding is 0.33 μg/m^3^.
Table 3-2 also shows that all workers included in the hot work job
category have maximum exposure levels that exceed 0.2 μg/m^3^. The
highest maximum exposure levels are associated with welding (2.21
μg/m^3^) and hot rolling/extrusion (0.56 μg/m^3^).

Table 3-3 indicates that 69 percent of the full-shift PBZ exposure
levels for workers classified in the hot work job category are less than
or equal to the lowest proposed PEL option of 0.1 μg/m^3^. Thirty-one
percent of the exposure levels for these workers are greater than 0.1
μg/m^3^, 12 percent of the exposure levels are greater than 0.2 μg/m^3^,
and less than one percent (reported as zero percent) of the exposure
levels exceed 1 μg/m^3^.

***Welding:*** Sheets of alloy strip are rolled from billets as single
coils on the hot mill. Smaller coils produced at the old hot mill are
welded together to produce full (longer-length) coils. The ends of the
coils are butt-welded together on an automated weld line with a TIG
(tungsten inert gas) welder. An operator equipped with a welding helmet
stands near the operation to monitor the process. Exposure controls
include the use of LEV with a slot-type exhaust hood at the welding
point-of-operation. Additionally, the coils are wetted with process
water (low-pressure water spray) to help reduce the generation of
beryllium oxide surface contamination both before and after welding
(i.e., before uncoiling the strip for welding and after the welded strip
has been re-coiled). Worker exposure might be associated with numerous
factors including the effectiveness of the LEV and surface wetting in
controlling operator exposure to welding fumes and beryllium oxide
surface contamination on the hot milled coils. Note that this welding
operation is no longer performed at the Elmore facility.

***Welding -- Additional Controls:*** As shown in Table 3-2, the median
exposure level for weld line operators is 0.33µg/m^3^. Table 3-3
indicates that all (100 percent) of the full-shift PBZ total beryllium
exposure levels reported for these workers are greater than the lowest
proposed PEL option of 0.1 μg/m^3^. Seventy-three percent of the
exposure levels are greater than 0.2 μg/m^3^, and six percent of the
exposure levels exceed 1 μg/m^3^. Additional controls are required to
further reduce worker exposure. Based on the available information,
these additional controls include:

-   Improving the effectiveness of surface wetting by more thoroughly
    wetting the coils with process water before and after welding or,
    using an alternative (or an additive to process water) that might
    better contain the surface contamination (beryllium oxide) on the
    coils. Note that most of the exposure associated with the weld line
    is due to handling and manipulating the coils (Kent, 2005).

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-   Enhancing the effectiveness of the LEV (e.g., balancing the exhaust
    flow with the shield gas). Reportedly the welding task itself can be
    performed without operator exposures if the LEV is balanced with the
    shield gas (Kent, 2005). As previously discussed, enhanced
    engineering and work practice controls together typically might be
    expected to reduce exposures by two to three times (Kent, 2005).
    Using this rule of thumb, beryllium exposures associated with the
    weld line might be reduced to median levels ranging between 0.1
    μg/m^3^ and 0.2 μg/m^3^ through enhanced LEV and wetting of the
    coils.

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-   Pickling the coils before welding. Pickling the coils before welding
    will achieve the greatest reduction in oxide-related exposures,
    perhaps by an order of magnitude (Kent, 2005).

***Welding -- Conclusion:*** Improved work practices (i.e., better
wetting of the coils) and LEV together might reduce the exposure of weld
line workers to median levels comparable with the lowest PEL options.
Nearly all workers might achieve exposure levels comparable to the
lowest PEL options if the coils are pickled prior to welding. This
particular TIG welding operation is no longer performed at the Elmore
facility therefore no additional controls are required at this time.

**3.6 POWDERING**

Table 3-2 shows that the median exposure level for powdering workers is
0.37 μg/m^3^ with a mean of 0.82 μg/m^3^ and a range of 0.06 μg/m^3^ to
11.52 μg/m^3^. These values represent a total of 72 full-shift PBZ
exposure levels reported for workers categorized in powdering work
groups. Powdering workers are involved in beryllium powder making or
handling activities including impact grinding, compact
loading/sintering, and near-net-shape (NNS) fabrication.

The median exposure levels for all three work groups included in the
powdering job category exceed the lowest proposed PEL option of 0.1
μg/m^3^. The median levels for these work groups include 0.59 μg/m^3^
for impact grinding; 0.22 μg/m^3^ for compact loading/sintering; and
0.41 μg/m^3^ for NNS processing.

As shown in Table 3-3, 11 percent of the full-shift PBZ total beryllium
levels for workers classified in the powdering job category are less
than or equal to the lowest proposed PEL option of 0.1 μg/m^3^.
Eighty-nine percent of the exposure levels are greater than 0.1 μg/m^3^,
71 percent of the exposure levels are greater than 0.2 μg/m^3^, and 21
percent of the exposure levels exceed 1 μg/m^3^.

***Impact Grinding:*** Impact grinding is a beryllium powder making
operation. Vacuum cast billets are prepared for machining, loaded into
lathes, and milled into chips. The beryllium chips are vacuum-conveyed
into collection containers and subsequently loaded into an impact
grinding (powder generating) operation. During impact grinding,
beryllium chips are injected into a high-speed air stream and impacted
against a beryllium target to generate beryllium powder. The beryllium
powder is sized, collected in containers, and then transferred to "all
white" powder blenders for mixing. The powder containers are manually
loaded and unloaded into/from the blending mill. The blended powder
containers are then transferred to the compact loading operation for
subsequent processing. The primary source of exposure is associated with
fugitive emissions when connecting/disconnecting chip and
powder-containing drums from the process (presumably due to work
practice issues and/or the design of the valve system). To a much lesser
extent, ductwork leaks in the impact grinding conveyance system (i.e.,
beryllium particles are abrasive) contribute to worker exposure.

Exposure controls for these activities include the use of LEV during
billet preparation (exhaust hood) and machining (LVHV source capture);
engineered powder drum breaks when loading/unloading drums at impact
grinding and powder blending work stations; the use of an enclosed
control room to isolate the operator; and painting surfaces white to
more easily identify (gray) beryllium powder contamination. No open
handling of beryllium powder occurs. Additionally, workers involved with
powdering activities have HEPA vacuum systems and a commercial wet
sweeper available for workplace cleaning.

***Impact Grinding -- Additional Controls:*** As indicated in Table 3-2,
the median exposure level for impact grinding is 0.59 μg/m^3^. Table 3-3
indicates that 19 percent of the full-shift PBZ exposure levels for
workers involved in the impact grinding operation are less than or equal
to the lowest proposed PEL option of 0.1 μg/m^3^. Eighty-one percent of
the exposure levels are greater than 0.1 μg/m^3^, 77 percent of the
exposure levels are greater than 0.2 μg/m^3^, and 31 percent of the
exposure levels exceed 1 μg/m^3^. Additional controls are required to
further reduce worker exposure. Based on the available information,
these additional controls include:

-   Improving work practices associated with make-break connections
    through operator training, work practice modifications, and/or
    better enforcement/supervision. Reportedly, there is a proper
    sequence of events that must occur during make-break powder transfer
    operations. Workers might not realize that following a certain
    sequence of steps makes a difference in their beryllium exposure. As
    previously discussed (decontamination workers), ERG assumes that
    enhanced work practices might achieve an average exposure reduction
    of 32 percent. Such an exposure reduction will reduce the median
    exposure level of impact grinding workers to 0.4 μg/m^3^.

-   Installing a fail-safe drum break system to prevent fugitive
    emissions at connection points during material transfer operations
    or fully enclosing the engineered drum breaks. Potential problems
    with the existing drum break system also include material retained
    inside valves and tubing, perhaps due to surface roughness; and, the
    inability to see or otherwise determine if all of the material
    transfer has occurred.

> Pharmaceutical quality packing head systems are used for
> filling/weighing operations involving high-hazard powders. Packing
> head systems provide a sealed connection between the filling device
> and the container for dust-free transfer of product. Vented and
> extraction type sealing heads are available for applications where
> container pressure must be avoided. Packing heads used in conjunction
> with laminar flow containment booths (containment isolator) further
> ensure operator safety during container filling. Or, as an
> alternative, containment booths can be used as secondary containment
> between two vessels during make-break operations. Typical applications
> for powder containment booths include large scale dispensing,
> weighing, and product sampling. (Absolute Control Systems, Inc., 2004;
> Hosokawa Micron Group, 2005). Additionally, customized double
> butterfly valves can be fabricated for applications where gas and
> dust-tight dosing and discharging of bulk materials is required in
> addition to stringent emission and leakage. Reportedly, pharmaceutical
> quality high containment powder and granule handling systems achieve
> dust control exposure levels of 0.1 µg/m^3^ or less (Hosokawa Micron
> Group, 2005).

-   Enhancing the preventive maintenance program for the impact grinder
    to prevent conveyance system leaks. Eliminating the potential for
    process-related leaks will help to further reduce operator exposure.
    The impact that process-related leaks have on operator exposure on
    any given day is reported to be very small (approximately one
    percent).

***Impact Grinding -- Conclusion:*** Enhanced work practices might
achieve an average exposure reduction of 32 percent resulting in a
median exposure level of 0.40 µg/m^3^ for impact grinding operators.
Pharmaceutical quality powder transfer and packaging systems would be
expected to achieve a greater level of exposure control than enhanced
work practices alone and reportedly can achieve dust control levels of
0.1 µg/m^3^ or less. Based on this information, ERG finds that nearly
all impact grinding workers might be able to achieve exposure levels
comparable to the lowest PEL options through the use of pharmaceutical
quality high containment powder handling systems.

***Compact Loading/Sintering:*** During compact loading, workers load
and cap vertically oriented cylindrical graphite dies with beryllium
powder. The dies are placed in a tall loading hood (approximately 15 to
20 feet tall) equipped with back and side-draft exhaust ventilation and
are top-loaded with beryllium powder received from the impact grinding
operation. Containers of powder are connected to the top of the compact
loading hood using engineered powder drum breaks to connect/disconnect
containers from the process. A worker is located inside the hood to
physically observe the loading process (with a flash light) in an effort
to prevent overloading of the die and a subsequent powder spill. During
loading, the beryllium powder is vibratorily packed (shaken and
compacted as much as possible). The loaded die is capped with a graphite
plug, removed from the loading hood, and transferred to a below ground
sintering furnace. During the sintering process, the powder is
consolidated into a billet in an inert environment using heat and
pressure. The finished billet is removed from the die (pushed out with a
hydraulic ram) in a die-stripping hood that is also equipped with
back-draft exhaust ventilation. The primary source of worker exposure is
associated with two activitiesinstalling/removing containers of powder
from the compact loading hood and die loading.

***Compact Loading/Sintering -- Additional Controls:*** As shown in
Table 3-2, the median exposure level for compact loading/sintering is
0.22 μg/m^3^. Table 3-3 indicates that 16 percent of the full-shift PBZ
exposure levels for workers involved in compact loading and sintering
are less than or equal to the lowest proposed PEL option of 0.1 μg/m^3^.
Eighty-four percent of the exposure levels are greater than 0.1 μg/m^3^,
52 percent of the exposure levels are greater than 0.2 μg/m^3^, and 26
percent of the exposure levels exceed 1 μg/m^3^. Additional controls are
required to further reduce worker exposure. Based on the available
information, these additional controls include:

-   Engineering controls to prevent powder overflows during die filling
    and workers from having to enter the loading hood to observe the
    process (e.g., through remote viewing or powder filling mechanisms
    with a weigh scale or timer function to prevent powder overflows).
    Powder filling/weighing systems with packing heads and containment
    booths that are engineered for use in the pharmaceutical industry
    might be applicable to the die filling operation as a means to
    prevent die overloading and powder spills. Reportedly, these high
    containment powder handling systems achieve dust control exposure
    levels of 0.1 µg/m^3^ or less (Hosokawa Micron Group, 2005). At a
    minimum, remote viewing could be used as an alternative to locating
    a worker inside the hood to physically observe the loading process
    with a flashlight. The exposure contribution due to die filling is
    not known; ERG therefore assumes that this task might account for 50
    percent of worker exposure.

-   Improving work practices through operator training, work practice
    modifications, and/or better enforcement/supervision to minimize
    exposure associated with the installation and removal of
    powder-containing drums from the compact loading hood. Reportedly,
    there is a proper sequence of events that must occur during
    make-break operations. Workers might not realize that following a
    certain sequence of steps makes a difference in their beryllium
    exposure. As previously discussed (decontamination workers), ERG
    assumes that enhanced work practices might achieve an average
    exposure reduction of 32 percent.

-   Installing a fail-safe drum break system to prevent fugitive
    emissions at connection points during material transfer or fully
    enclosing engineered drum breaks. Potential problems with the
    existing drum break system might also include material retained
    inside valves and tubing, perhaps due to surface roughness; and, the
    inability to see or otherwise determine if all the material transfer
    has occurred. Pharmaceutical quality packing head systems are used
    for filling/weighing operations involving high-hazard powders.
    Packing head systems provide a sealed connection between the filling
    device and the container for dust-free transfer of product. Vented
    and extraction type sealing heads are available for applications
    where container pressure must be avoided. Packing heads used in
    conjunction with laminar flow containment booths (containment
    isolator) further ensure operator safety during container filling.
    Or, as an alternative, containment booths can be used as secondary
    containment between two vessels during make-break operations.
    Typical applications for powder containment booths include large
    scale dispensing, weighing, and product sampling. (Absolute Control
    Systems, Inc., 2004; Hosokawa Micron Group, 2005). Additionally,
    customized double butterfly valves can be fabricated for
    applications where gas and dust-tight dosing and discharging of bulk
    materials is required in addition to stringent emission and leakage.
    Reportedly, pharmaceutical quality high containment powder and
    granule handling systems achieve dust control exposure levels of 0.1
    µg/m^3^ or less (Hosokawa Micron Group, 2005).

***Compact Loading/Sintering -- Conclusion:*** An exposure reduction of
50 percent might be achieved through the installation of remote viewing
(or another equally effective engineering control) so that workers do
not need to enter the die loading hood to observe die filling. This
exposure reduction will result in a median exposure level of 0.11
µg/m^3^. Additionally, enhanced work practices associated with drum
breaks might further reduce exposures by an average of 32 percent.
Pharmaceutical quality powder transfer, handling, and filling/weighing
systems would be expected to achieve a greater level of control than
enhanced work practices alone and reportedly can achieve dust control
levels of 0.1 µg/m^3^ or less. Based on this information, ERG finds that
nearly all impact grinding workers might be able to achieve exposure
levels comparable to the lowest PEL options through the combined use of
remote viewing and pharmaceutical quality high containment powder
handling systems.

***NNS Fabrication:*** NNS (near-net-shape) refers to a process where
the amount of beryllium scrap generated by the fabrication of beryllium
parts or shapes is minimized. Beryllium powder is loaded into dies and
consolidated into preformed shapes with one or more techniques involving
heat and/or pressure (cold and hot isostatic pressing). After
consolidation, the dies are unloaded using different techniques
depending on the type of die (rubber, steel or copper). Rubber dies are
used for cold isostatic pressing and steel and copper dies are used for
hot isostatic pressing. Steel and copper dies have seams that are
manually welded.

Powder loading is conducted in a separate room inside ventilated glove
box-type enclosures (glove hood) equipped with central vacuum drops
(inside) for cleaning. Containers of powder are connected/disconnected
to the top of the glove hood using engineered powder drum breaks.
Operators load and clean the dies by vacuuming/wet wiping, and then
remove them from the glove hoods. The powder loading room is under
negative pressure to minimize the potential for contaminating adjacent
spaces. In addition, when exiting the NNS fabrication area, workers must
step on a tack mat and pass through an air wash chamber.

Dies are unloaded differently depending on the type of die. Rubber dies
are cut open inside an exhaust hood. Steel and copper dies are loaded
into a nitric acid bath and dissolved. The acid tank is located in a
separate room and is equipped with an exhausted partial enclosure open
at the top/face for loading purposes. Reportedly, a significant amount
of nitrogen oxides are generated depending on the number of dies in the
tank, but is contained by the process LEV.

Worker exposure to beryllium during NNS fabrication is primarily
associated with fugitive emissions when (1) opening glove hoods to
remove loaded dies and (2) connecting/disconnecting product containers
from the glove hoods (presumably due to work practice issues and/or the
design of the valve system). Near-net-shape fabrication workers also
manually weld steel and copper die seams. However, the metal dies are
new (i.e., the metal dies are dissolved away in a nitric acid bath and
do not get reused) and are not expected to be associated with operator
exposure.

***NNS -- Additional Controls:*** As shown in Table 3-2, the median
exposure level for NNS operators is 0.41 μg/m^3^. Table 3-3 indicates
that all (100 percent) of the full-shift PBZ exposure levels for workers
involved with NNS fabrication are greater than the lowest proposed PEL
option of 0.1 μg/m^3^. Seventy-eight percent of the exposure levels are
greater than 0.2 μg/m^3^, and eight percent of the exposure levels
exceed 1 μg/m^3^. Additional controls are required to further reduce
worker exposure. Based on the available information, these additional
controls include:

-   Improving work practices through operator training, work practice
    modifications, and/or better enforcement/supervision to minimize
    exposures associated with NNS fabrication. Examples include:
    enhancing cleaning practices regarding the dies and/or the interior
    surfaces of the glove hoods (e.g., doing a better job of
    washing/wiping down the interior of the glove hood before removing
    dies); waiting longer to open the glove hood after die filling; and
    following the proper sequence of events that must occur during
    make-break operations. As previously discussed (decontamination
    workers), ERG assumes that enhanced work practices might achieve an
    average exposure reduction of 32 percent where work practice issues
    primarily contribute to operator exposure.

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-   Enhancing glove hood ventilation and/or effectiveness. Glove hood
    design criteria for high toxicity and radioactive materials are
    specified by the American Conference of Governmental Industrial
    Hygienists (ACGIH, 2001). The existing glove hood should be
    evaluated to determine if it meets the recommended design criteria
    or requires modification (e.g., increased ventilation and/or
    enhanced hood design). Additionally, total isolation technologies
    employed by the pharmaceutical industry for highly hazardous
    materials (such as half-suit isolators, glove boxes, and automated
    technologies for removing containers/packages of hazardous powders
    from the isolators) would be expected to provide a significant
    reduction in employee exposure associated with the die loading
    operation. Pharmaceutical quality powder transfer, handling, and
    filling/weighing systems reportedly can achieve dust control levels
    of 0.1 µg/m^3^ or less (Hosokawa Micron Group, 2005).

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-   Installing a fail-safe drum break system to prevent fugitive
    emissions at connection points during material transfer or fully
    enclosing engineered drum breaks. Potential problems with the
    existing drum break system might also include material retained
    inside valves and tubing, perhaps due to surface roughness; and, the
    inability to see or otherwise determine if all the material transfer
    has occurred. Pharmaceutical quality packing head systems are used
    for filling/weighing operations involving high-hazard powders.
    Packing head systems provide a sealed connection between the filling
    device and the container for dust-free transfer of product. Vented
    and extraction type sealing heads are available for applications
    where container pressure must be avoided. Packing heads used in
    conjunction with laminar flow containment booths (containment
    isolator) further ensure operator safety during container filling.
    Or, as an alternative, containment booths can be used as secondary
    containment between two vessels during make-break operations.
    Typical applications for powder containment booths include large
    scale dispensing, weighing, and product sampling. (Absolute Control
    Systems, Inc., 2004; Hosokawa Micron Group, 2005). Additionally,
    customized double butterfly valves can be fabricated for
    applications where gas and dust-tight dosing and discharging of bulk
    materials is required in addition to stringent emission and leakage.
    Reportedly, pharmaceutical quality high containment powder and
    granule handling systems achieve dust control exposure levels of 0.1
    µg/m^3^ or less (Hosokawa Micron Group, 2005).

***NNS -- Conclusion:*** Enhanced work practices alone might achieve an
average exposure reduction of 32 percent resulting in a median exposure
level of 0.28 µg/m^3^ for NNS operators. Improving the effectiveness of
the glove hood by ensuring compliance with ACGIH design criteria for
high toxicity and radioactive materials could significantly reduce
operator exposures if it is determined that the hood's performance is
less than optimal. Enhanced work practices and LEV together are
estimated to further reduce exposures by two to three times resulting in
median exposure levels comparable to the lowest PEL option.
Additionally, pharmaceutical quality powder transfer, handling, and
filling/weighing systems would be expected to achieve a greater level of
control than enhanced work practices alone and reportedly can achieve
dust control levels of 0.1 µg/m^3^ or less. Based on this information,
ERG finds that nearly all NNS fabrication workers might be able to
achieve exposure levels comparable to the lowest PEL options through the
combined use of enhanced work practices and pharmaceutical quality high
containment powder handling systems.

**3.7 CHEMICAL OPERATIONS**

Table 3-2 indicates that the median exposure level for chemical
operation workers is 0.47 μg/m^3^ with a mean of 1.02 μg/m^3^ and a
range of 0.05 μg/m^3^ to 9.64 μg/m^3^. These values represent a total of
20 full-shift PBZ total beryllium exposure levels reported for workers
categorized in chemical operation work groups. These workers include
only those involved with the production of beryllium sulfate salt
(primary beryllium oxide production process). Manufacturing operations
involving the conversion of beryllium hydroxide to ammonium beryllium
fluoride (ABF) were in operation during the 1999 baseline exposure
monitoring, but have since been decommissioned and will not be discussed
further.

***Beryllium Sulfate Salt:*** In the primary beryllium oxide production
process, high-purity beryllium sulfate salts are produced by dissolving
beryllium hydroxide in sulfuric acid, filtering the solution to removed
insoluble materials/impurities, and then concentrating the resulting
filtrate through evaporation/cooling.

The beryllium sulfate salt manufacturing process is almost entirely
enclosed and isolated from workers (i.e., chemical additions and mixing
is automated and enclosed) except at the process entry and exit points.
At the process entry point, operators load drums of beryllium hydroxide
into a barrel tilter inside an enclosed and ventilated feed station.
After the beryllium hydroxide is loaded into the process, the operator
cleans/rinses the empty drums with water inside the enclosure before
removal. At the process exit point, the material is separated and sized
by an automated wet screening step and then drops into drums at a
filling station equipped with LEV (collar-type LEV hood on drums during
filling). After the drums are filled, the operator installs and seals
the drum lids and removes and transfers the drums to the beryllium oxide
furnaces using a lift truck equipped with a barrel grabber.

Operator exposure is primarily attributable to (1) work practice issues
associated with unloading and cleaning drums at the process entry point
and (2) drum filling/over-filling at the process exit point. Working in
close proximity to a high exposure operation (i.e., the wet plant) that
has since been decommissioned has also been a major source of exposure.
The exposure reduction due to the decommissioned wet plant is not known;
however, an industry expert estimates that exposures might have been
reduced by as much as 50 percent (Kent, 2005). If this is the case,
decommissioning the wet plant might have reduced the median exposure
level to approximately 0.24 μg/m^3^.

***Beryllium Sulfate Salt -- Additional Controls:*** As shown in Table
3-2, the median exposure level for beryllium sulfate salt workers is
0.47 μg/m^3^. Table 3-3 indicates that only five percent of the
full-shift PBZ total beryllium exposure levels for beryllium sulfate
workers are less than or equal to the lowest proposed PEL option of 0.1
μg/m^3^. Ninety-five percent of the exposure levels exceed 0.1 μg/m^3^,
85 percent of the exposure levels are greater than 0.2 μg/m^3^, and 15
percent of the exposure levels exceed 1 μg/m^3^. Additional controls are
required to further reduce worker exposure. Based on the available
information, these additional controls include:

-   Improved work practices associated with drum rinsing and filling
    through operator training, work practice modifications, and/or
    better enforcement/supervision (e.g., enhance the level of cleaning
    achieved during manual drum rinsing/cleaning in the raw material
    feed station; and improve the ability to determine when drum filling
    is complete.) As discussed previously, work practice improvements
    might be expected to achieve an average exposure reduction of 32
    percent where work practice issues primarily contribute to operator
    exposure.

-   Enhanced engineering controls for (1) drum unloading and rinsing in
    the raw material feed station and (2) drum filling/weighing at the
    process exit to reduce exposures associated with drum filling and
    prevent drum overflows (e.g., interlocked product containers with a
    weigh scale or timer function to prevent drum overflows).

> Pharmaceutical quality dust free tipping booths are designed for
> handling highly hazardous powders and granules and reportedly can
> achieve dust control levels of 0.1 µg/m^3^ or less. Total operator
> protection is assured with automatic container lifting/tipping, high
> visibility viewpoints and glove port access. A modular design allows
> application customization for the handling of a wide variety of
> containers. Empty container disposal and cleaning systems can be
> incorporated into the tipping and discharge systems. (Hosokawa Micron
> Group, 2005).
>
> Pharmaceutical quality packing head systems are used for
> filling/weighing operations involving high-hazard powders. Packing
> head systems provide a sealed connection between the filling device
> and the container for dust-free transfer of product. Vented and
> extraction type sealing heads are available for applications where
> container pressure must be avoided. Packing heads used in conjunction
> with laminar flow containment booths (containment isolator) further
> ensure operator safety during container filling. Or, as an
> alternative, containment booths can be used as secondary containment
> between two vessels during make-break operations. Typical applications
> for powder containment booths include large scale dispensing,
> weighing, and product sampling. (Absolute Control Systems, Inc., 2004;
> Hosokawa Micron Group, 2005). Additionally, customized double
> butterfly valves can be fabricated for applications where gas and
> dust-tight dosing and discharging of bulk materials is required in
> addition to stringent emission and leakage. Reportedly, pharmaceutical
> quality high containment powder and granule handling systems achieve
> dust control exposure levels of 0.1 µg/m^3^ or less (Hosokawa Micron
> Group, 2005

***Beryllium Sulfate Salt -- Conclusion:*** Decommissioning the nearby
wet plant might have reduced the median exposure level of beryllium
sulfate salt workers by 50 percent to approximately 0.24 μg/m^3^.
Improved work practices might further reduce exposures by approximately
32 percent resulting in a median exposure level of 0.16 µg/m3. Enhanced
engineering controls, especially for drum filling operations (e.g.,
laminar flow high containment booths), are likely to achieve a greater
level of exposure control than improved work practices alone.
Reportedly, pharmaceutical quality powder/granule handling systems can
achieve dust control levels of 0.1 µg/m^3^ or less. Based on this
information, ERG finds that nearly all beryllium sulfate salt workers
might be able to achieve exposure levels comparable to the lowest PEL
option by decommissioning (or isolating) the wet plant and through the
use of pharmaceutical quality high containment powder/granule handling
systems.

**3.8 FURNACE OPERATIONS**

As indicated in Table 3-2, the median exposure level for furnace
operations workers is 0.68 μg/m^3^ with a mean of 3.80 μg/m^3^ and a
range of 0.05 μg/m^3^ to 254.23 μg/m^3^. These values represent a total
of 172 full-shift PBZ total beryllium exposure levels reported for
workers categorized in furnace operations work groups. These workers
include those involved with alloy, high beryllium, and beryllium oxide
furnace operations. Furnace operations involving the manufacture of
beryllium pebbles from beryllium fluoride (fluoride and reduction
furnaces) were in operation during the 1999 baseline exposure
monitoring, but have since been decommissioned and will not be discussed
further.

The median exposure levels for the individual furnace operations range
from 0.27 μg/m^3^ (beryllium oxide) to 5.56 μg/m^3^ (high beryllium
atomization). Table 3-2 also shows that all workers in the furnace
operations job category have maximum exposure levels that exceed 2
μg/m^3^. The highest exposure levels are reported for alloy induction
(48.07 μg/m^3^) and high beryllium atomization (254.23 μg/m^3^) furnace
operations.

Table 3-3 indicates that only five percent of the full-shift PBZ total
beryllium exposure levels reported for furnace operations are less than
or equal to the lowest proposed PEL option of 0.1 μg/m^3^. Ninety-five
percent of the exposure levels are greater than 0.1 μg/m^3^, 83 percent
of the exposure levels are greater than 0.2 μg/m^3^, and 32 percent of
the exposure levels exceed 1 μg/m^3^.

***Alloy Arc Furnace:*** The alloy arc furnace operations produce a cast
four percent copper-beryllium master alloy that is subsequently
re-melted and diluted with other metals to form alloys with a reduced
percentage of beryllium that are cast, hot rolled, and otherwise
fabricated (NIOSH, 1972). These activities include the production of
beryllium pellets and furnace operations. Beryllium hydroxide is rotary
calcined to create beryllium oxide. Feed material consisting of
beryllium oxide, carbon, and ventilation fines, is mixed and pelletized
to create beryllium pellets. Copper and beryllium pellets (following
sampling) are then charged remotely into the arc furnace. After
charging, the furnace is tapped into a transfer ladle and dross is
removed. The metal is allowed to cool, degassed with nitrogen lances,
and then poured into an ingot conveyor machine that generates 50-pound
ingots. The pelletizing and furnace operations are fully enclosed and
ventilated by a 40,000 cubic feet per minute dust collection system.
(Kent et al, 2001).

The pelletizer's work tasks include monitoring feed material bin levels,
unplugging storage bins, and ensuring proper operation of the calcining
and pelletizing systems. Furnace operators weigh the raw copper, dump
55-gallon drums of beryllium hydroxide into the drum washing station,
charge and tap the furnace, remove and recycle dross, add furnace
electrodes, and cast ingots (Kent et al, 2001).

The arc furnace is charged through a computer-controlled closed system
and is completely covered with a ventilated enclosure (furnace/room
hood). An enclosed and ventilated operator control booth is available
and upon leaving the furnace area workers must step onto a tack mat and
pass through an air wash chamber. Reportedly, the work tasks associated
with the highest potential exposure include preparing the pelletizer
feed material and sampling pellets (Kent et al, 2001). Operator
interaction with the furnace is also a possible source of exposure. For
example, furnace operators manipulate long tools (approximately ten feet
long) that they slide in and partially out of the furnace. Operator
movement and positioning with respect to access openings in the furnace
hood and contaminated tools might be a factor associated with potential
exposure. Additionally, the pelletizing and arc furnace operations are
integrated with each other. Beryllium contamination and migration
associated with the pelletizing operation might be a factor in the
exposure of the arc furnace operator and vice versa. Other sources of
exposure include electrode replacement (not conducted on a regular
basis) and process-related leaks associated with the calciner (e.g.,
gasket/seal failures). Process equipment leaks and fugitive emissions
might account for up to 40 percent of worker exposure (Kent, 2005).

***Alloy Arc Furnace -- Additional Controls:*** As shown in Table 3-2,
the median exposure level for alloy arc furnace operators is 0.95
μg/m^3^. Table 3-3 indicates that all (100 percent) of the full-shift
PBZ total beryllium exposure levels for arc furnace operations are
greater than the lowest proposed PEL option of 0.1 μg/m^3^. Ninety-seven
percent of the exposure levels are greater than 0.2 μg/m^3^, and 44
percent of the exposure levels exceed 1 μg/m^3^. Additional controls are
required to further reduce worker exposure. Based on the available
information, these additional controls include:

-   Improving work practices to minimize potential exposures associated
    with the arc furnace operation (rubbing/skimming, tapping, casting,
    drum loading). Work practice improvements might include additional
    employee training, better enforcement of existing procedures, and/or
    the development of new or revised procedures to better control
    workplace exposures. For example, arc furnace operators could lower
    their beryllium exposures by waiting until their tools have cooled
    (and are not fuming) before withdrawing them from the furnace.
    During casting, workers need to skim dross from the ingot mold and
    carefully place it in the appropriate collection containers. If
    workers handle the scale in a careless and sloppy manner, they
    increase the level of contamination in the work area and their
    exposure to beryllium. Additionally, the oxide scale is a gel-like
    material and workers reportedly do not always place it into the
    collection container. As discussed previously, work practice
    improvements might be expected to achieve an average exposure
    reduction of 32 percent where work practice issues primarily
    contribute to operator exposure. Such a reduction in exposure will
    result in a median exposure level of approximately 0.65 μg/m^3^.

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-   Improving engineering controls for pellet and oxide sampling
    (pelletizer operator only). For example, creating a small opening
    (or some other type of engineering intervention) for workers to
    sample pellets as opposed to opening the pelletizer access door. A
    beryllium alloy plant used five automatic Isolok™ solid material
    samplers in their calcining and reduction operation to sample fresh
    beryllium oxide from the calciner and storage bins, flue dust,
    blended material, and finished product (four percent
    beryllium-copper alloy). The pneumatic samplers operate on a
    positive displacement, closed collection principle. A fixed amount
    of solid sample is withdrawn with each stroke of the single moving
    plunger. The extracted sample falls into a closed sample container
    (plastic collection bottle) that is manually removed on a periodic
    basis and carried to the laboratory for analysis. A new collection
    container is manually attached to the sampler for the next sampling
    cycle. In addition to the automatic samplers, the plant also
    utilized a negative pressure isolation/enclosure chamber for the
    beryllium oxide storage bin and the calciner operation. To evaluate
    the solid material sampling operations, NIOSH investigators
    collected area air samples over five shifts at 13 locations in the
    calcining and reduction area. The average beryllium concentrations
    ranged from 0.1 µg/m^3^ to 1.06 µg/m^3^. NIOSH investigators
    concluded that the design of the automatic solid material samplers
    significantly contributed to low worker exposures (NIOSH, 1982;
    1983).

-   Enhancing the preventive maintenance program for the calciner and
    other process equipment to prevent process-related leaks. Reducing
    the number or magnitude of process-related leaks will reduce
    fugitive emissions and contribute to lower worker exposures.

***Alloy Arc Furnace -- Conclusion:*** For those exposures primarily
attributed to work practice issues, work practice enhancements might
achieve an average exposure reduction of 32 percent resulting in a
median exposure level of 0.65 µg/m^3^ for arc furnace workers.
Implementing the use of automatic solid material samplers (or other
equally effective engineering intervention) is expected to reduce
(perhaps significantly) operator exposures associated with pellet/oxide
sampling. As previously discussed, improved work practices and
engineering controls together might reduce exposures by two to three
times resulting in median exposure levels ranging from 0.32 µg/m^3^ to
0.48 µg/m^3^. Additional exposure reductions, by as much as 40 percent,
might be achieved by improving the preventive maintenance program for
the calciner and other process equipment to reduce process-related leaks
and fugitive emissions. Such a reduction might further reduce exposures
to median levels ranging from 0.2 µg/m^3^ to 0.3 µg/m^3^. To achieve a
median level comparable to the lowest PEL option, respiratory protection
will be necessary.

***Alloy Induction Furnaces:*** The induction furnace melting and
casting operations produce beryllium alloys containing a lower
percentage of beryllium (0.1% to 2%). Furnace charges are prepared in
mix stations, placed in tubs, and charged in the furnaces through
pneumatically controlled carts. After the charge has melted, the furnace
walls are rubbed to remove buildup, dross is skimmed off the surface,
and the heat is degassed and cast into water-cooled molds (Kent et al,
2001).

Two workers operate each furnace: a deck worker and a floor worker.
Tasks conducted by the deck worker with potential exposure include
charging, rubbing, skimming, degassing, and changing full dross barrels.
Tasks performed by the floor worker include setting up the mold;
heating, placing, and cleaning the tundish; and pouring the furnace. The
tasks associated with the most significant exposures are reported to be
rubbing and skimming, changing full dross barrels, and cleaning the
tundish (Kent et al, 2001; Kent, 2005). Dross-related tasks present the
greatest exposure potential (perhaps as much as 70 percent of worker
exposure) because the beryllium content of dross is 16 percent (Kent,
2005). Dross formation is minimized, but not eliminated, by melting
under inert gas (e.g., inert gas blanketing with liquid argon) or by
melting in air with a graphite cover or blanket. The percent reduction
in dross formation achieved with these techniques is not available to
ERG. However, inert gas or molten metal blanketing technologies
developed by one company reportedly reduce dross/slag formation by up to
50 percent (Air Products, 2005).

Operator control booths equipped with air conditioning and HEPA air
filters are installed near the furnaces (for furnace and casting
operators) and custom-designed LEV hoods and/or enclosures are used to
control worker exposure at furnace openings. Tool holders and integrated
dross chute/collection systems have LEV as well as tundish cleaning
activities. In addition, workers exiting the melting and casting area in
the "New Cast Shop" must clean their work shoes with a foot cleaner and
pass through a HEPA-filtered air shower.

***Alloy Induction Furnaces -- Additional Controls:*** As shown in Table
3-2, the median exposure level for alloy induction furnace workers is
0.50 μg/m^3^. Table 3-3 indicates that only five percent of the
full-shift PBZ total beryllium exposure levels reported for these
workers are less than (or equal to) the lowest proposed PEL option of
0.1 μg/m^3^. Ninety-five percent of the exposure levels are greater than
0.1 μg/m^3^, 82 percent of the exposure levels are greater than 0.2
μg/m^3^, and 23 percent of the exposure levels exceed 1 μg/m^3^.
Additional controls are required to further reduce worker exposure.
Based on the available information, these additional controls include:

-   Enhancing work practices through operator training, work practice
    modifications, and/or better enforcement/supervision. For
    example, (1) during drossing in the Old Cast Shop operators can
    overfill the dross tray. When the overfilled tray is tipped into the
    dross barrel, the dross chute LEV can be overwhelmed by excessive
    fumes causing increased worker exposure. (2) When removing rub bars
    from the furnace, operators need to lay the tools on the furnace
    deck to allow the fuming parts to cool near the furnace LEV before
    placing the tools in the ventilated holder. (3) After casting,
    furnace operators need to clean the tundish and furnace pour spout
    and carefully place "cleanings" in the appropriate collection
    containers. If operators handle the cleanings in a careless and
    sloppy manner, they increase the level of contamination in the work
    area and their exposure to beryllium. As discussed previously, work
    practice improvements might be expected to achieve an average
    exposure reduction of 32 percent where work practice issues
    primarily contribute to operator exposure.

-   Enhancing and/or installing LEV where appropriate. Potential
    examples in the Old Cast Shop include the following: (1) modifying
    the dross chute LEV to accommodate the extremes during filling of
    the dross barrel; (2) ensuring adequate LEV throughout drossing
    (reportedly there is a short period of time with inadequate LEV when
    the filled dross tray is tipped into the dross barrel); and (3)
    using LEV while mechanically removing (i.e., prying/chipping)
    solidified dross and metal from the tundish. Improved LEV and work
    practices together typically can be expected to reduce exposures by
    two to three times (Kent, 2005). Such an exposure reduction will
    result in median exposures ranging from 0.17 μg/m^3^ to 0.25
    μg/m^3^.

-   Evaluating the current use of graphite and inert gas blankets to
    determine if additional reductions in dross formation are feasible.
    Additional reductions in dross formation will contribute to lower
    worker exposure. However, ERG is not able to estimate an exposure
    reduction that might be achieved because the effectiveness of the
    current techniques is not available.

-   Automating (partially or fully) the drossing operation to eliminate
    manual skimming, rubbing, and changing of the dross barrel. The
    feasibility of mechanically removing dross and deposits on furnace
    walls needs to be investigated. Several induction furnace
    manufacturers contacted by ERG suggest that it is possible to
    automate dross removal and retrofit existing furnaces; however, the
    costs associated with such automation for each furnace would be
    considerable (Pillar, 2005; Inductotherm, 2005; ABB, 2005). Furnace
    manufacturers will not develop the technology unless there is a
    demand for it. One furnace manufacturer is creating partial
    automation for dross removal from iron and aluminum furnaces for
    some of its customers (ABB, 2005). The automation process is costly
    because the scrapers and dross removal equipment have to vary
    according to the type, size, and height of the furnace.
    Additionally, scrapers made from steel alloys that are used for
    aluminum furnaces could not be used for beryllium alloys. Beryllium
    alloys require higher melting temperatures, therefore more expensive
    material, such as titanium, would have to be used so that the blades
    of the scrapers can withstand the higher temperatures without
    melting.

> Removing slag deposits on furnace walls is a very "sensitive" task
> requiring the correct amount of hand pressure during rubbing and
> scraping of the furnace lining after casting. If done incorrectly, the
> refractory lining could be damaged (cracked) possibly resulting in
> superheated molten metal and/or a furnace explosion during subsequent
> melting cycles. Furnace manufacturers suggest that employers might be
> reluctant to allow modifications to furnace designs because of
> concerns that dross removal features might impact the safety of
> furnaces. Although automated dross removal (i.e., skimming dross off
> the surface of molten metal) appears possible, manual rubbing of
> furnace walls is likely more efficient than mechanical removal and may
> be preferred due to safety concerns (Pillar, 2005; Inductotherm, 2005;
> ABB, 2005; AFS, 2005).

***Alloy Induction Furnaces -- Conclusion:*** For those exposures
primarily attributed to work practice issues, work practice enhancements
might achieve an average exposure reduction of 32 percent resulting in a
median exposure level of 0.34 µg/m^3^ for alloy induction furnace
operators. Enhanced work practices and LEV together might reduce
exposures two to three times resulting in median exposures ranging from
0.17 µg/m^3^ to 0.25 µg/m^3^. To achieve a median exposure level
comparable to the lowest PEL option, the available information indicates
that respiratory protection will be necessary.

Eliminating manual skimming, rubbing, and barrel changing by automating
the drossing process would be expected to achieve the most significant
exposure reduction (perhaps by as much as 70 percent). However, the
feasibility of automated/mechanical drossing for alloy induction
furnaces has not been determined at this time. Additional reductions in
exposure through reduced dross formation might also be possible;
however, as with automated drossing, ERG lacks adequate information to
estimate an exposure reduction.

***High Beryllium Vacuum Casting:*** Vacuum casting is a furnace
operation designed to produce feedstock (vacuum-cast billets) for
powder-making operations (National Materials Advisory Board, 1989).
Beryllium feed material (e.g., reclaimed chips and scrap) is
vacuum-melted inside a tilt-pour induction furnace and poured into
graphite molds to produce round billets that are approximately three to
four feet in length. The billets are manually cleaned (pressure washed)
and prepared inside an exhaust hood and then transferred to the
powder-making operation. Likely sources of exposure include charge
make-up (the charge is prepared inside a hood that the operator enters),
and cleaning/preparing billets for powder making.

***High Beryllium Vacuum Casting -- Additional Controls:*** As shown in
Table 3-2, the median exposure level for high beryllium vacuum casting
operators is 0.31 μg/m^3^. Table 3-3 indicates that all (100 percent) of
the full-shift PBZ total beryllium exposure levels for vacuum casting
workers are greater than the lowest proposed PEL option of 0.1 μg/m^3^.
Sixty-six percent of the exposure levels are greater than 0.2 μg/m^3^,
and 33 percent of the exposure levels exceed 1 μg/m^3^. Additional
controls are required to further reduce worker exposure. Based on the
available information, these additional controls include:

-   Isolating the operator from the charge make-up hood (i.e., the
    operator does not enter and work inside the hood) and the charge
    make-up activity from the rest of the operation. This additional
    control likely can be achieved by automating/isolating some aspects
    of the operation and more effective LEV (enhanced through additional
    exhaust flow and/or better hood design). Additionally,
    pharmaceutical quality high containment isolator systems for powder
    and granule handling would be expected to provide significant dust
    control, reportedly to dust control levels of 0.1 μg/m^3^ or less
    (Hosokawa Micron Group, 2005). The exposure contribution due to the
    charge make-up process is not known. ERG therefore estimates that
    charge make-up might account for 50 percent of worker exposure.
    Given this assumption, significantly reducing worker exposure by
    redesigning the charge make-up process might result in a median
    exposure level of approximately 0.16 μg/m^3^.

-   Performing a task analysis to identify which tasks associated with
    billet preparation contribute most to worker exposure (about seven
    different tasks are associated with billet preparation) and
    implementing work practice improvements and LEV
    changes/modifications to further reduce worker exposure. For
    example, the effectiveness of the billet preparation hood could be
    enhanced through additional exhaust flow and/or better hood design.
    An LEV system meeting ACGIH design criteria would be expected to
    achieve a significant reduction in exposure (assuming that the
    existing billet preparation hood is not effective enough in
    controlling operator exposure). As discussed previously, work
    practice and LEV improvements combined typically can be expected to
    reduce exposures by two to three times (Kent, 2005). Such a
    reduction will further reduce exposures to median levels ranging
    from 0.05 μg/m^3^ to 0.08 μg/m^3^.

***High Beryllium Vacuum Casting -- Conclusion:*** Redesigning the
charge make-up process is expected to reduce the median exposure level
of vacuum casting workers to approximately 0.16 μg/m^3^. Work practice
and LEV improvements for billet preparation may further reduce exposures
to median levels less than the lowest PEL option should a need for such
improvements be identified. Given the uncertainty associated with the
need for additional controls for billet preparation, ERG finds that
respiratory protection may be necessary to achieve a median exposure
level comparable to the lowest PEL option.

***High Beryllium Atomization:*** Atomization is a furnace operation
where the final product is aluminum-beryllium or beryllium powder.
Appropriate feed material (e.g., aluminum, beryllium scrap, and virgin
materials) is vacuum-melted in a small furnace (approximately eight to
ten inches in diameter and 18 to 24 inches in length). The furnace melt
is introduced into an argon air stream under high pressure and the
molten metal is obliterated into small particles that fall into a
collection cone at the base of the atomizer. Worker exposure is
primarily associated with powder breaks when removing filled collection
containers at the base of the atomizer. There also are a number of other
factors that might affect exposure. The atomizer operator prepares the
charge and charges the furnace by physically picking up the charge
material and manually placing it in the furnace. This operation was done
without LEV during the 1999 baseline exposure monitoring. The operator
performs rubbing and skimming; and also cleans the atomizer collection
cone and a ceramic tundish inside the furnace that directs the molten
metal to the atomizer jets. The tundish is manually cleaned (e.g., by
chipping with a bar) between pours. It is cleaned in place inside the
furnace chamber which is under negative pressure. The chipped material
is removed from the furnace chamber, placed in a ventilated chute and
drops into a collection drum. Information regarding the potential
exposure associated with this task is not available.

The atomizer collection cone is cleaned infrequently (about once a year)
and is also under negative pressure. It is large enough that the
operator can physically get his head/torso inside and is cleaned by
vacuuming and scraping the sides down. Potential exposure is associated
with this cleaning task because the operator can place his head inside
the cone; however, no information is available regarding the exposure
associated with this task.

After the 1999 baseline exposure monitoring, several engineering changes
were made to the atomization operation. These exposure control changes
included the following: (1) replacing the bag house collector with a
larger capacity HEPA-filtered collector; (2) replacing the ventilation
ductwork with correctly sized ductwork for maximum effectiveness; (3)
installing a HEPA-filtered make-up air unit (laminar flow design); (4)
modifying the powder collection system to reduce the number of drum
breaks (by using larger collection containers); (5) enclosing the
furnace/tundish access area with a box-like Plexiglas enclosure (with
access door) to better contain beryllium contamination and migration;
and (6) installing LEV over/around the furnace charging area.
Reportedly, a total exposure reduction of approximately two to three
times was achieved with these additional controls (Kent, 2005). ERG
estimates that such a reduction lowered the median exposure to levels
ranging from 1.8 to 2.78 µg/m^3^.

***High Beryllium Atomization -- Additional Controls:*** As shown in
Table 3-2, the median exposure level for atomization operators is 5.56
μg/m^3^. Table 3-3 indicates that all (100 percent) of the full-shift
PBZ total beryllium exposure levels for these workers are greater than
0.5 μg/m^3^ and 69 percent of the exposure levels exceed 1 μg/m^3^.
Additional controls are required to further reduce worker exposure.
Based on the available information, these additional controls include:

-   Performing a task analysis to identify work methods associated with
    atomization (e.g., charge make-up, rubbing/skimming, and make/break
    connections) that contribute most to worker exposure and
    implementing work practice improvements to further reduce worker
    exposure. For example, there is a proper sequence of events that
    must occur during make-break connections. Workers might not realize
    that following a certain sequence of steps makes a difference in
    their beryllium exposure. Work practice improvements might include
    additional employee training, better enforcement of existing
    procedures, and/or the development of new or revised procedures to
    better control workplace exposures. As discussed previously, work
    practice improvements might be expected to achieve an average
    exposure reduction of 32 percent where work practice issues
    primarily contribute to operator exposure. Such a reduction will
    reduce the median exposure to levels ranging from 1.2 μg/m^3^ to 1.9
    μg/m^3^.

-   Re-evaluating worker exposure associated with powder breaks and
    removing filled collection containers at the base of the atomizer.
    If still elevated, install a fail-safe drum break system to prevent
    fugitive emissions at the collection container connection point at
    the base of the atomizer or fully enclose the powder drum break
    (e.g., with a high containment isolation booth). Potential problems
    with the existing drum break system also may include material
    retained inside valves and tubing, perhaps due to surface roughness;
    and, the inability to see or other wise determine if all the
    material transfer has occurred.

> Pharmaceutical quality packing head systems are used for
> filling/weighing operations involving high-hazard powders. Packing
> head systems provide a sealed connection between the filling device
> and the container for dust-free transfer of product. Vented and
> extraction type sealing heads are available for applications where
> container pressure must be avoided. Packing heads used in conjunction
> with laminar flow containment booths (containment isolator) further
> ensure operator safety during container filling. Or, as an
> alternative, containment booths can be used as secondary containment
> between two vessels during make-break operations. Typical applications
> for powder containment booths include large scale dispensing,
> weighing, and product sampling. (Absolute Control Systems, Inc., 2004;
> Hosokawa Micron Group, 2005). Additionally, customized double
> butterfly valves can be fabricated for applications where gas and
> dust-tight dosing and discharging of bulk materials is required in
> addition to stringent emission and leakage. Reportedly, pharmaceutical
> quality high containment powder and granule handling systems achieve
> dust control exposure levels of 0.1 µg/m^3^ or less (Hosokawa Micron
> Group, 2005).

***High Beryllium Atomization -- Conclusion:*** Additional controls
implemented after the 1999 baseline exposure monitoring reduced operator
exposure by two to three times. Median exposure levels are currently
estimated to range from 1.8 µg/m^3^ to 2.78 µg/m^3^. Worker exposure is
attributed to make-break powder connections and work practice issues.
Work practice improvements might achieve an average exposure reduction
of 32 percent resulting in median exposure levels ranging from 1.2
μg/m^3^ to 1.9 μg/m^3^. A pharmaceutical quality high containment powder
transfer (filling/weighing) system would be expected to achieve a
significant reduction in exposure assuming that worker exposure is
primarily associated with powder breaks when removing filled collection
containers at the base of the atomizer. Reportedly dust control levels
of 0.1 µg/m^3^ or less can be achieved. Given the available information,
ERG finds that median exposure levels comparable to the lowest PEL
option are achievable.

***Beryllium Oxide Furnace:*** Wet-screened beryllium sulfate salt is
calcined in hearth furnaces to produce beryllium oxide powders. The
furnaces have top-ventilated, full enclosures at the loading/unloading
point that consist of removable metal wall panels. To load the furnaces,
operators remove one of the front wall panels from the enclosure, empty
drums of wet beryllium sulfate salt into large rectangular refractory
containers with a lift truck equipped with a barrel grabber, and then
load the containers into the furnace chamber. The refractory containers
are thick walled (approximately one foot thick), about 10 feet wide and
20 feet long, and are positioned on a roller track that leads into the
furnace chamber. The furnace chamber is under negative pressure and is
accessed through a set of doors. Although the furnace has LEV, bake-out
emissions are released into the workplace and significantly affect
worker exposure. After the furnace is loaded and closed, operators
reinstall the removable wall panel. The beryllium sulfate salt gets
fired in the furnace for several days and is transformed into a
fluidized bed of beryllium oxide powder. After a cooling period
(approximately one day), the operators again remove a front wall panel
from the enclosure and manually vacuum-convey and screen (size) the
beryllium oxide powder to collection containers. The beryllium oxide
powder inside the vacuum-conveyance system is enclosed and isolated from
the operator and the product collection containers are located in a
ventilated hood. To vacuum-convey the beryllium oxide powder, operators
use a long vacuum wand that is about ten feet long.

Key sources of operator exposure include work practices and/or
engineering controls associated with the following: charging the furnace
with beryllium sulfate salt; empty drum handling and cleaning; manually
vacuum-conveying the beryllium oxide powder to collection containers;
filling/overfilling the collection containers; and changing out product
drums. For example, during furnace charging and vacuum filling
operations, workers should never have more than one panel removed from
the furnace enclosure. Removing more than one panel can affect the
exhaust flow within the enclosure. Additionally, during container
filling the vacuum wand gets contaminated and contributes to worker
exposure if it is pulled too far out. To reduce the potential for
exposure workers need to leave the wand inside the ventilated enclosure.

The exposure breakdown by activity is not known. Exposures associated
with furnace charging and bake-out emissions are estimated to account
for 50 percent of worker exposure. Fifteen percent of this exposure
might be attributed to furnace charging and empty drum handling and
cleaning with bake-out emissions responsible for the remainder (about 35
percent). The other 50 percent of worker exposure is estimated to be due
to filling and changing out product collection containers (Kent, 2005).

***Beryllium Oxide Furnace -- Additional Controls:*** As shown in Table
3-2, the median exposure level of beryllium oxide furnace operators is
0.27 μg/m^3^. Table 3-3 indicated that 20 percent of the full-shift PBZ
total beryllium exposure levels for these workers are less than or equal
to the lowest proposed PEL option of 0.1 μg/m^3^. Eighty percent of the
exposure levels are greater than 0.1 μg/m^3^, 60 percent of the exposure
levels are greater than 0.2 μg/m^3^, and 33 percent of the exposure
levels exceed 1 μg/m^3^. Additional controls are required to further
reduce worker exposure. Based on the available information, these
additional controls include:

-   Performing a task analysis to identify work methods that contribute
    most to worker exposure and implementing work practice improvements
    to further reduce exposure. For example, during furnace charging and
    vacuum filling workers should never have more than one panel removed
    from the furnace enclosure. Removing more than one panel can
    adversely affect the exhaust flow within the enclosure.
    Additionally, during container filling the vacuum wand gets
    contaminated and contributes to worker exposure if it is pulled too
    far out. To reduce the potential for exposure workers need to leave
    the wand inside the ventilated enclosure. Work practice improvements
    might include additional employee training, better enforcement of
    existing procedures, and/or the development of new or revised
    procedures to better control workplace exposures. As discussed
    previously, work practice improvements might be expected to achieve
    an average exposure reduction of 32 percent where work practice
    issues primarily contribute to operator exposure. Such an exposure
    reduction will lower the median exposure level of beryllium oxide
    furnace workers to approximately 0.18 μg/m^3^.

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-   Increasing the effectiveness of the exhaust ventilation in the
    paneled furnace enclosure by replacing/fixing damaged wall panels
    and/or increasing the exhaust flow. The exposure reduction that
    might be achieved with this improvement is not known but estimated
    to be ten percent (Kent, 2005).

-   Enhancing engineering controls associated with filling and changing
    out product collection containers (estimated to account for 50
    percent of worker exposure). For example, high hazard laminar flow
    powder booths (containment isolator) with integrated weighing
    systems can reduce operator exposure associated with drum filling
    operations. Pharmaceutical quality packing head systems used in
    conjunction with laminar flow booths can be used to further ensure
    operator safety during container filling. Packing head systems
    provide a sealed connection between the filling device and the
    container for dust-free transfer of product. Vented and extraction
    type sealing heads are available for applications where container
    pressure must be avoided. Reportedly, pharmaceutical quality high
    containment powder handling systems achieve dust control exposure
    levels of 0.1 µg/m^3^ or less (Hosokawa Micron Group, 2005).

-   Enhancing/installing engineered controls for furnace charging and
    empty drum handling and cleaning (estimated to account for 15
    percent of worker exposure). Pharmaceutical quality dust free
    tipping booths are designed for handling highly hazardous powders
    and granules. Total operator protection is assured with automatic
    container lifting/tipping, high visibility viewpoints and glove port
    access. A modular design allows application customization for the
    handling of a wide variety of containers. Empty container disposal
    and cleaning systems can be incorporated into the tipping and
    discharge systems. Reportedly, pharmaceutical quality high
    containment powder and granule handling systems achieve dust control
    levels of 0.1 µg/m^3^ or less (Hosokawa Micron Group, 2005).

-   Eliminating furnace bake-out emissions (perhaps by
    sealing/ventilating furnace openings and/or redesigning the furnace
    doors). The estimated exposure reduction that might be achieved with
    this engineering control is 35 percent. However, ERG lacks adequate
    information regarding the source(s) of the emissions and whether
    engineering improvements are feasible. Reportedly the beryllium
    oxide furnaces date back to the nineteen-fifties.

***Beryllium Oxide Furnace -- Conclusion:*** Based on the available
information, enhanced work practices and increased exhaust ventilation
in the paneled furnace enclosure together are estimated to reduce worker
exposure by approximately 42 percent. Such a reduction will result in a
median exposure level of 0.16 µg/m^3^ for beryllium oxide furnace
operators. Pharmaceutical quality engineering controls for product
container filling/weighing and changing are estimated to further reduce
the median exposure to the lowest proposed PEL option.

# REFERENCES

ABB, 2005. Telephone conversation between Raymond Gilli, ABB USA,
Norwalk, Connecticut

and Eastern Research Group, Inc. January 14.

Absolute Control Systems, Inc, 2004. Absolute Control Systems, Inc. web
site

[http://www.absolutecontrolsys.com](http://www.absolutecontrolsys.com/).
Accessed December 9, 2004.

AFS, 2005. Telephone conversation between Fred Kohloff, American Foundry
Society, Health

> and Safety Committee, Schaumburg, Illinois and Eastern Research Group,
> Inc. January 14.

Air Products, 2005. Rapidfire MMB -- Molten Metal Blanketing. Air
Products and Chemicals,

Inc., Allentown, PA. Information available online at
[http://www.airproducts.com](http://www.airproducts.com/).

Accessed February 25.

Brush Wellman, 2004. Individual full-shift personal breathing zone
(lapel-type) exposure

levels collected by Brush Wellman in 1999 at their Elmore, Ohio facility
were

provided to ERG in August 2004. Brush Wellman, Inc., Cleveland, Ohio.

Brush Wellman. 2002. Brush Wellman web site.
[http://www.beminc.com/web/bpdweb.nsf/]{.underline} Accessed March 1,
2002

Brush Wellman. Not dated. Beryllium metal matrix composite avionic
materials. Brush Wellman, Inc., Elmore, OH.

Cant, S.M., and L.A. Legendre, 1982. Assessment of Occupational Exposure
to Arsenic,

Copper, and Lead in a Western Copper Smelter. American Industrial
Hygiene

Association Journal 43(4): 223-226.

Cecala, A.B., J.A. Organiscak, J.A. Zimmer, W.A. Heitbrink, E.S. Moyer,
M. Schmitz, E.

Ahrenholtz, C.C. Coppock, and E.H. Andrews, 2005. Reducing Enclosed Cab
Drill

Operator's Respirable Dust Exposure with Effective Filtration and
Pressurization

Techniques. Journal of Occupational and Environmental Hygiene (2):
54-63. January.

Corbett, 2004. Personal discussions between Marc L. Corbett (consultant)
and Eastern Research

Group, Inc. August.

Cunningham, L. 2000. Telephone conversation between Larry Cunningham of
the USGS and ERG, Inc., April 25, 2000.

Cunningham, L. 1999b. Beryllium. In U.S. Geological Survey Metal Prices
in the United States Through 1998.

Cunningham, L. 1997. Beryllium. U.S. Geological SurveyCMinerals
InformationC1997.

Facility A-1. 2000. Telephone conversation between Facility A-1 and ERG,
Inc., January 23.

Facility B-1. 2000. Telephone conversation between Facility B-1 and,
ERG, Inc., February 8.

Facility C-1. 2000. Telephone conversation between Facility C-1 and ERG,
Inc., February 8.

Facility D-1. 2000. Telephone conversation between Facility D-1 and ERG,
Inc., January 27.

Facility F-1. 2000. Telephone conversation between Facility F-1 and ERG,
Inc., February 8.

Facility F-2. 2000. Personal communication between Facility F-2 and ERG,
Inc. Feb.9.

Facility G-1. 2000. Telephone conversation between Facility G-1 and ERG,
Inc., February 8.

Facility H-1. 2000. Telephone conversation between Facility H-1 and ERG,
Inc., January 26 and February 14.

Facility I-1. 2000. Telephone conversation between Facility I-1 and ERG,
Inc., January 26 and 28.

Facility J-1. 2000. Telephone conversation between Facility J-1 and ERG,
Inc., January 27.

Facility K-1. 2000. Telephone conversation between Facility K-1 and ERG,
Inc., January 27.

Facility L-1. 2000. Telephone conversation between Facility L-1 and ERG,
Inc., January 28.

Facility M-1. 2000. Telephone conversation between Facility M-1 and ERG,
Inc., January 27.

Facility N-1. 2000. Telephone conversation between Facility N-1 and ERG,
Inc., February 8.

Facility O-1. 2000. Telephone conversation between Facility O-1 and ERG,
Inc., February 8.

Harris, Carl. 2000. Telephone conversation between Lynn Knight of ERG,
and Carl Harris, Director of Human Relations, NGK Metals, Level, PA.
January 21.

Harris, Carl. 2002. Telephone conversation between John Eyraud of ERG,
and Carl Harris, Director of Human Relations, NGK Metals, Level, PA.
February 21.

Hosokawa Micron Group, 2005. Telephone conversation between ERG and a
technical

representative from Hosokawa Micron Powder Systems, Summit, New Jersey.
January

13\. Product information is available at the following web sites

<http://www.hosokawa.com/web/Stott/> and
[http://www.hosokawa.com](http://www.hosokawa.com/).

Inductotherm, 2005. Telephone conversation between Charles Vivian,
Inductotherm Group,

Rancocas, New Jersey and Eastern Research Group, Inc. January 13.

Irwin, 2003. Overexposure to Crystalline Silica in a Foundry Operation,
OSHA Compliance

Issues Column, R.E. Fairfax, Column Editor. Applied Occupational and
Environmental

Hygiene 18(1):18-21. January.

Kent, M.S., T.G. Robins, and A.K. Madl, 2001. Is Total Mass or Mass of
Alveolar-Deposited

Airborne Particles of Beryllium a Better Predictor of the Prevalence of
Disease? A

Preliminary Study of a Beryllium Processing Facility. Applied
Occupational and

Environmental Hygiene 16(5): 539-558.

Kent, 2005. Telephone conversation between ERG and Michael S. Kent, CIH,
CSP, Director

Environmental, Health and Safety, Brush Wellman Inc., Elmore, Ohio.
January 5.

Kreiss, K., M. Kroz, B. Zhen, H. Wiedermann, and B. Barna, 1997. Risks
of Beryllium Metal Disease Related to Work Processes at a Metal, Alloy,
and Oxide Production Plant. Occupational and Environmental Medicine. Vol
54, pp 605-612.

Linnainmaa, M.T., 1995. Control of Exposure to Cobalt During Grinding of
Hard Metal Blades.

Applied Occupational and Environmental Hygiene 10(8): 692-697. August.

Maples, T.W., J.A. Jacoby, D.E. Johnson, G.L. Ter Haar, and F.M.
Buckingham, 1982.

Effectiveness of Employee Training and Motivation Programs in Reducing
Exposure to

Inorganic Lead and Lead Alkyls. American Industrial Hygiene Association
Journal

43(9): 692-694.

McCawley, M. 2000. Air and Surface Sampling for Beryllium. Presentation
by the National Institute for Occupational Safety and Health to the
Occupational Safety and Health Administration. Washington, D.C. October.

National Materials Advisory Board. 1989. Beryllium Metal Supply Options.
NMAB Report No.

452\. Washington, D.C.: National Academy Press \[limited distribution
document available

from Defense Technical Information Center\].

NIOSH, 1989. National occupational exposure survey (NOES). Cincinnati,
OH, U.S. Department of Health and Human Services, Public Health Service,
Center for Disease Control, National Institute for Occupational Safety
and Health.

NIOSH, 1972. Industrial Hygiene Survey of the Brush Wellman Plant, June
12-16, 1972 and August 21-25, 1972. Report No. IWS-37.11/NTIS No.
PB82100686. Environmental Investigations Branch, Division of Field
Studies and Clinical Investigations, National Institute for Occupational
Safety and Health, Cincinnati, Ohio.

NIOSH, 1977. NIOSH Testimony to the Department of Labor, Occupational
Safety and Health Administration, Public Hearing on the Occupational
Standard for Beryllium. Statement of Edward J. Baier, Deputy Director,
National Institute for Occupational Safety and Health, Center for
Disease Control, U.S. Department of Health, Education, and Welfare.
August 19.

NIOSH, 1982. Preliminary Survey Report: Solid Material Sampling
Operations at Cabot

Berylco Beryllium Alloy Plant, Level Pennsylvania. National Institute
for Occupational

Safety and Health, Division of Physical Sciences and Engineering,
Engineering Control

Technology Branch, Cincinnati, Ohio. Report No. ECTB 113-14a. June 10.

NIOSH, 1983. Indepth Survey Report: Solid Material Sampling Operations
at Cabot Berylco Beryllium Alloy Plant, Level Pennsylvania. National
Institute for Occupational Safety and Health, Division of Physical
Sciences and Engineering, Engineering Control Technology Branch,
Cincinnati, Ohio. Report No. ECTB 113-14b. March.

NIOSH, 1990. Health Hazard Evaluation Report No. 89-270. Harrisburg
Steam Generation Facility, Harrisburg, Pennsylvania. Department of
Health and Human Services, Centers for Disease Control and Prevention,
National Institute for Occupational Safety and Health, Hazard
Evaluations and Technical Assistance Branch, Division of Surveillance,
Hazard Evaluations, and Field Studies, Cincinnati, Ohio. HETA
89-270-2080. November.

NIOSH, 1991. Health Hazard Evaluation Report No. 90-361. Seville
Centrifugal Bronze, Inc., Seville, Ohio. Department of Health and Human
Services, Centers for Disease Control and Prevention, National Institute
for Occupational Safety and Health, Hazard Evaluations and Technical
Assistance Branch, Division of Surveillance, Hazard Evaluations, and
Field Studies, Cincinnati, Ohio. HETA 91-0093-2126. July.

NIOSH, 2001. Health Hazard Evaluation Report: 92-0311, CSX
Transportation, Inc.,

Cincinnati, Ohio: National Institute for Occupational safety and Health.
January.

NIOSH, 2003. In-Depth Survey Report of Control of Respirable Dust and
Crystalline Silica from Breaking Concrete with a Jackhammer. U.S.
Department of Health and Human Services, Centers for Disease Control and
Prevention, National Institute for Occupational Safety and Health,
Division of Applied Research and Technology, Engineering and Physical
Hazards Branch, Cincinnati, Ohio. Report No. EPHB 282-11a February.

NIOSH, 2004. Health Hazard Evaluation Report No. 2003-0114-2924. Felker
Brothers Corporation, Marshfield, Wisconsin. Department of Health and
Human Services, Centers for Disease Control and Prevention, National
Institute for Occupational Safety and Health, Hazard Evaluations and
Technical Assistance Branch, Division of Surveillance, Hazard
Evaluations, and Field Studies, Cincinnati, Ohio. January.

OSHA, H005C-6-9-5-3. U.S. Department of Labor. Occupational Safety and
Health Administration. Beryllium Docket No. H005C. Exhibit No. 6-9-5-3.
Document Title: Attachment 2.1. Primary Beryllium Manufacturing and
Processing Facility. Docket ID No. 1570194. Comments received in
response to Federal Register of November 26, 2002. Available on-line at
<http://dockets.osha.gov/search/documentDetails.asp?udi=1570179&usr=B>

OSHA SEP Inspection Report 303207518. OSHA Special Emphasis Program
(SEP) Inspection

Report 303207518.

Parsonage, T. 1994. Thermal/system performance of a lightweight
beryllium composite heat sink for advanced electronic packaging.
Presentation at Seventh International SAMPE Electronics Conference. June
20 to 23.

Pharmaceutical Manufacturer A, 2004. Telephone conversation between ERG
and

Pharmaceutical Manufacturer A. December 2.

Pillar, 2005. Telephone conversation between Brian Brazinski, Pillar
Induction Company, LLC,

Brookfield, Wisconsin and Eastern Research Group, Inc. January 13.

Sam, 2004. Telephone conversation between Kwasi Sam, Illinois Department
of Commerce and

Community Affairs (Illinois On-Site Consultation Program) and ERG.
October 8.

Sentry Equipment Corporation, 2005. Telephone conversations between ERG
and a sales

representative at Sentry Equipment Corporation, Oconomowoc, Wisconsin.
February 18

and 22. See also
[http://www.bristolequipment.com](http://www.bristolequipment.com/)

Sussell, A., C. Hart, D. Wild, and K. Ashley, 1999. An Evaluation of
Worker Lead Exposures

and Cleaning Effectiveness During Removal of Deteriorated Lead-Based
Paint. Applied

Occupational and Industrial Hygiene 14: 177-185.

Thomas Register of American Manufacturers. 2000. Internet site search
under beryllium oxide.

[http://www3.thomasregister.com/.]{.underline}

29 CFR 1910.1001, Appendix F\[B\](7). Asbestos Standard - Appendix F.
Work Practices and

Engineering Controls for Automotive Brake and Clutch Inspection,
Disassembly, Repair

and Assembly. U.S. Department of Labor, Occupational Safety and Health

Administration, Washington, DC.

29 CFR 1910.1001(k)(1). Asbestos Standard -- Housekeeping. U.S.
Department of Labor,

Occupational Safety and Health Administration, Washington, DC.

29 CFR 1910.1018(k)(1). Inorganic Arsenic Standard -- Housekeeping. U.S.
Department of

Labor, Occupational Safety and Health Administration, Washington, DC.

29 CFR 1910.1025(h)(1). Lead Standard -- Housekeeping. U.S. Department
of Labor,

Occupational Safety and Health Administration, Washington, DC.

29 CFR 1910.1027(k)(1). Cadmium Standard -- Housekeeping. U.S.
Department of Labor,

Occupational Safety and Health Administration, Washington, DC.

U.S. Bureau of the Census. 1999a. 1997 Economic Census, Manufacturing
Industry Series. U.S. Government Printing Office. Washington, DC.

U.S. DHHS. 1993. Toxicological Profile for Beryllium. U.S. Department of
Health and Human Services. Public Health Service. Agency for Toxic
Substances and Disease Registry. Washington, DC.

Westbrook, D. 1996. Occupational exposure to beryllium. Fundamentals of
Industrial Hygiene.

FPMD-664. November 14.

Williams, D.R. and K. Sam, 1999. Illinois Ready-Mixed Concrete
Association Industrial Hygiene Study: October 1997 through June 1999.
Illinois Department of Commerce and Community Affairs, Illinois On-Site
Consultation Program, 100 West Randolph Street, Chicago, Illinois.
\[Unpublished Data\]

Zalk, D., 2000. Exposure Assessment Strategy for the Reduction of
Airborne Silica During Jackhammering Activities. Presented at the
American Industrial Hygiene Conference and Exposition, Orlando, Florida.
May 20-25, 2000.

[^1]: Kreiss et al. do not explicitly state that the Brush Wellman
    Elmore plant is the subject of their paper. Brush Wellman, however,
    explicitly acknowledges this fact on its Web site. Brush Wellman,
    Inc., \<http://www.befacts.com/timeline/nineties.html\>. Accessed
    April 25, 2000.

[^2]: Note that for the purpose of evaluating exposure with and without
    the control, these readings represent actual sampling times (rather
    than calculated 8-hour time-weighted averages), and were based on
    short sample durations ranging from 54 to 186 minutes, during which
    the workers used jackhammers continuously (Zalk, 2001).