Bunge Corporation

Plain-English summary

OSHA cited three Bunge grain-handling facilities under the mineral-dust provisions of 29 C.F.R. § 1910.1000. The Commission held that Table Z-3 applies only to mineral dusts and did not cover organic soybean or grain dust under its inert-or-nuisance-dust listing. It also rejected the alternative crystalline-quartz allegation because the same mineral-dust table did not give fair notice that its formulas applied to predominantly organic grain dust containing small amounts of quartz. The Commission found the silica formula difficult to interpret and unsupported by any common industry understanding or clear source material. It therefore vacated all cited items and alternative allegations in the three consolidated dockets.

Decision snapshot

• Cited standard(s): 29 C.F.R. §§ 1910.1000(c) and 1910.1000(e)
• Outcome: Nuisance-dust and crystalline-silica allegations vacated in all three dockets.
• Key point: A mineral-dust table did not give grain handlers fair notice that it regulated organic grain dust or small quartz content within that dust.

Full text (OSHRC public release)

Docket No. 77-1622_78-0838_78-2213

SECRETARY OF LABOR,

Complainant,

v.

BUNGE CORPORATION,

Respondent.

OIL, CHEMICAL AND ATOMIC WORKERS

INTERNATIONAL UNION AND ITS LOCAL 4-447,

Authorized Employee

Representative

(Docket No. 77-1622).

OSHRC Docket Nos. 77-1622, 78-0838 & 78-2213

DECISION

Before:  BUCKLEY, Chairman; RADER and WALL, Commissioners.

BY THE COMMISSION:

These three consolidated cases are before the Occupational Safety and Health
Review Commission under 29 U.S.C. � 661(i), section 12(j) of the Occupational Safety and
Health Act of 1970, 29 U.S.C. �� 651-678 ("the Act").  The Commission is
an adjudicatory agency, independent of the Department of Labor and the Occupational Safety
and Health Administration ("OSHA").  It was established to resolve disputes
arising out of enforcement actions brought by the Secretary of Labor under the Act and has
no regulatory functions.  See section 10(c) of the Act, 29 U.S.C. � 659(c).

The three cases have been consolidated on review under Commission Rule 9, 29
C.F.R. � 2200.9. because they involve common parties and common questions of law and
fact.  Bunge Corporation ("Bunge") is one of the largest employers within
the international grain-handling industry.  As a result of separate inspections of
its facilities in Destrehan, Louisiana (Docket No. 77-1622), Galveston, Texas (No.
78-0838), and Osceola, Arkansas (No. 78-2213), Bunge was issued citations alleging
violations of the inert or nuisance dust provision of the mineral dust standard at all
three of these workplaces.[[1]]  The principal issue on review is whether
Administrative Law Judge David G. Oringer erred in vacating these citations on the ground
that the inert or nuisance dust provision does not apply to grain dust.  Also on
review, in Docket No. 77-1622, are the judge's finding of a violation of the crystalline
quartz silica provision of the mineral dust standards[[2]] and the judge's rejection of
various procedural defenses.[[3]]

We conclude that neither the inert or nuisance dust provision nor the crystalline
quartz silica provision of the mineral dust standard can be applied to regulate employee
exposure to grain dust.  On this ground, we vacate each of the citation items on
review.  In light of our disposition, we need not reach the procedural issues raised
by Bunge in Docket No. 77-1622.

I

A

On March 4, 1977, OSHA began an inspection of Bunge's marine terminal grain
elevator at its export port facility in Destrehan, Louisiana.  The citation at issue
in Docket No. 77-1622 is based on three air contaminant samples taken by industrial
hygienist ("IH") William D. Gribble during that inspection.  Two total dust
samples and one respirable dust sample were obtained on April 27.[[4]]  The record
establishes, and the parties agree, that the dust collected in these samples was soybean
dust, which is a type of grain dust.[[5]]

As a result of its inspection, OSHA issued a citation to Bunge alleging violations of 29
C.F.R. �� 1910.1000 (c) and (e).  See note 1 supra .  The citation
alleged that employees on the fourth floor bin deck and on the shipping gallery were
exposed on April 27 to levels of dust that exceeded the mineral dust standard's
permissible exposure limits for respirable inert or nuisance dust and for total inert or
nuisance dust.[[6]]  The citation further alleged that Bunge failed to determine and
implement feasible administrative or engineering controls to reduce those dust levels
within permissible limits.

Bunge contested the citation and, in its notice of contest, requested an informal
conference with OSHA.  At this conference, Bunge argued that the inert or nuisance
dust provision does not apply to the cited conditions because Table Z-3 applies only to
mineral dusts, and grain dust is not a mineral dust.  OSHA's representatives
indicated that they would take Bunge's contentions under advisement.

Two days later, the Secretary obtained an extension of time to file the complaint
in Docket No. 77-1622.  This additional time was used for two purposes--to obtain a
laboratory analysis of the three dust samples collected on April 27 and to consult with
OSHA's national office on the legal and policy questions raised by Bunge about the scope
of the standard.

On June 20, the Bunge air contaminant samples were transmitted from OSHA's New
Orleans Area Office to OSHA's testing laboratory in Salt Lake City.  The lab was
asked to determine if there was any mineral content in the samples.  Three separate
analyses were conducted for this purpose.  On June 27, lab chemist Willard C. Dixon
conducted a petrographic analysis, which is essentially no more than a visual examination
through a microscope using polarized light.  Dixon saw only organic materials in the
three samples.  He saw no particles of crystalline quartz silica or any other
mineral.  He reported to his supervisor that his analysis "yielded 100% soybean
dust."

On July 8, lab chemist John C. Germ conducted an x-ray diffraction analysis on the
samples.  The purpose of this far more sophisticated analysis was to determine
whether two specific substances--crystalline quartz silica and cristobalite--were present
in the samples.  Based on his analysis, Germ concluded that the samples did not
contain cristobalite, but did contain crystalline quartz silica.  The quartz content
of each sample was calculated to be less than 5% by weight of all the dust collected.
 On July 11, Germ reported his results to the New Orleans Area Office.  Using
these results, IH Gribble computed the PEL's for crystalline quartz silica at Bunge's
workplace and concluded that these PEL's had been exceeded.[[7]]

During the same time period that the Secretary's representatives were awaiting the results
of the laboratory analysis, they also sought to resolve Bunge's contention that the inert
or nuisance dust provision of the mineral dust standard does not apply to soybean dust.
Initially, this question was presented to OSHA's Regional Office in Dallas, which in turn
sought a determination at the national level. Thus, on June 30, a memorandum ("the
Holder memo") was sent from an official in the Dallas Regional Office (Holder) to the
Office of Field Coordination, a branch of the national OSHA office.  The national
office was informed that the question of whether the inert or nuisance dust provision
applies to soybean dust had been raised as an issue in a contested case.  It was also
informed of a "telephone discussion with Herbert Stokinger of the A.C.G.I.H. TLV
Committee who agrees that only those substances containing mineral dust should be cited
under Table Z-3."[[8]]

On July 13, the OSHA national office responded by sending a memorandum ("the
Wilson-Tice memo") from the Deputy Director for Federal Compliance and State Programs
(Wilson) to the Dallas Regional Administrator (Tice). The OSHA Deputy Director concluded
that vegetable and animal dusts are not covered under Table Z-3 because they are not
"mineral dusts." In particular, the memorandum stated, "[s]oybean dust is a
vegetable dust and should not be cited under Table Z-3 of 29 CFR 1910.1000."[[9]]

On July 26, shortly after the New Orleans Area Office had received both lab
chemist Germ's report on the quartz content of the three samples and the Wilson-Tice memo
on the inapplicability of the cited provision, the Secretary's counsel filed the delayed
complaint in Docket No. 77-1622.  The complaint continued to allege noncompliance
with the mineral dust standard based on Bunge's failure to implement feasible
administrative or engineering controls to reduce excessive dust levels within permissible
limits. The complaint also continued to base the charge of excessive dust levels on the
three air contaminant samples that were taken on the fourth floor bin deck and the
shipping gallery on April 27.  However, the Secretary sought to amend the citation
through the complaint to allege that the permissible exposure limits that were exceeded on
that date were the PEL's for crystalline quarts silica rather than the PEL's for inert or
nuisance dust.  Several weeks later, the Secretary moved to amend his pleadings so as
to allege in the alternative noncompliance with the inert or nuisance dust provision, with
the crystalline quartz silica provision, or with both provisions of the mineral dust
standard.  These motions to amend were granted despite Bunge's objections.
 Accordingly, Docket No. 77-1622 proceeded to a hearing on the merits of the two
alternative charges.

B

In his decision in Docket No. 77-1622, Judge Oringer vacated the allegation
that Bunge violated the inert or nuisance dust provision of the mineral dust standard, but
affirmed the alternative allegation that Bunge violated that same standard's crystalline
quartz silica provision.  He characterized the violation as nonserious, modified the
abatement requirement, and assessed a penalty of $100.

The judge concluded that the inert or nuisance dust provision cannot be applied to
regulate employee exposure to grain dust.  In effect, he entered alternate
holdings:  (a) the provision does not apply to grain dust because it applies only to
mineral dusts or (b) even if grain dust falls within the intended scope of the provision,
it cannot be enforced against grain handlers because it does not provide the
constitutionally required fair notice that it is applicable.  Concerning the scope of
the cited provision, the judge stated:

Patently Table Z-3 prohibits excess exposure of employees to mineral
dusts.  All of the substances listed in Table Z-3 are mineral despite the fact that
coal may have an organic base.  In this cause the only dusts collected were not
mineral dust, but soybean dust, an organic non-inert substance.

On review, the Secretary argues that the judge erred in vacating the inert or
nuisance dust allegation.  He argues that the inert or nuisance dust provision should
be applied to the cited facts based on the "plain meaning" of the term
"nuisance dust," the intent of the drafters as revealed in the history of the
provision's development, and the history of the provision's subsequent enforcement as a
limitation on both organic and mineral dusts.  In elaborating on his "plain
meaning" argument, the Secretary contends that the term "nuisance dust" has
generally and consistently been understood, both in the industrial hygiene profession and
in the grain-handling industry, to include vegetable as well as mineral dusts.

The Secretary further claims that his enforcement action is consistent with the
intent of the ACGIH, the drafters of the inert or nuisance dust TLV's.[[10]]  He
asserts that grain dust is biologically inert in that it normally does not result in
irreversible health effects such as scarring of the lungs.  He points to provisions
of two ACGIH-TLV's pamphlets that suggest that such biologically inert dusts are properly
classified as "inert or nuisance dust," regardless of whether they are vegetable
or mineral dusts.[[11]] Accordingly, the Secretary reasons, grain dusts are covered by the
OSHA mineral dust standard because they are covered under the source standard.

C

We conclude that the mineral dust standard applies only to mineral
dusts.  Because it is undisputed that soybean dust is not a mineral dust, neither of
the provisions allegedly violated by Bunge applies to the cited conditions. 
Accordingly, both of the alternative allegations in Docket No. 77-1622 must be vacated.

In determining the proper interpretation of the mineral dust standard, we look
primarily to the language of the standard.  "There is, of course, no more
persuasive evidence of the purpose of a statute than the words by which the legislature
undertook to give expression to its wishes."  Griffin v. Oceanic Contractors,
Inc ., 458 U.S. 564, 571 (1982), quoting United States v. American Trucking
Associations , 310 U.S. 534, 543 (1940).[[12]]  The standard requires employers to
limit the exposure of their employees within permissible exposure limits whenever the
employees are exposed "to any material listed in Table Z-3."  Table Z-3 is
captioned "Mineral Dusts" and includes, in addition to the PEL's for "inert
or nuisance dust" and "crystalline quartz silica," PEL's for two other
"polymorphs" of silica (cristobalite and tridymite), for amorphous silica
(including natural diatomaceous earth), for five specified silicates, for graphite, and
for coal dust.[[13]]  Bunge argues that the table is limited on its face to mineral
dust, and that all of the dusts listed in Table Z-3 are mineral dusts.  Although the
Secretary attempted to prove that Table Z-3 includes three dusts that are not mineral
dusts, the judge found against the Secretary on this factual issue, and we conclude that
his finding is supported by the record.[[14]]  We therefore adopt the judge's finding
that all of the materials in Table Z-3 are commonly understood to be minerals or mineral
dusts.  Moreover, the listing for "inert or nuisance dust" corroborates the
firm impression given by the table that organic substances are not included within it
because organic matter is not chemically inert.[[15]]  In short, the language of the
table, including its title, shows that it is limited to mineral dust.

The Secretary nevertheless urges that the phrase "inert or nuisance
dust" should, in contrast with the other dusts regulated by Table Z-3, be interpreted
in accordance with a "common understanding" by industrial hygienists and the
grain-handling industry that it includes vegetable dusts.  The Secretary apparently
would have us ignore the fact that the other provisions of the standard apply only to
mineral dusts.  However, we adhere to the principle that the provisions of a standard
should be interpreted in the context of the entire standard.  See State Highway
Commission of Missouri v. Volpe , 479 F.2d 1099, 1111-1112 (8th Cir. 1973) (a section
of a statute should not be read in isolation but rather in the context of the whole act).
  See generally , 2A Sutherland Statutory Construction �
46.05 (4th ed. 1984).

In any event, even if we consider the inert or nuisance dust provision in
isolation, we are not convinced that the term "inert or nuisance dust" has a
special meaning that is commonly understood within the industrial hygiene profession and
the grain-handling industry.  The Secretary's assertion of a common understanding in
the industrial hygiene profession is contradicted by the record evidence.  IH Gribble
and Dr. Richard testified in support of the Secretary's interpretation.  However, the
documentary evidence establishes that OSHA Deputy Director for Federal Compliance and
State Programs Wilson, OSHA Assistant Regional Administrator Holder, and "Herbert
Stokinger of the A.C.G.I.H. TLV Committee" all agreed with Bunge's interpretation.
 Thus, industrial hygienists obviously disagree on the meaning of the provision.

The record also contains no support for the assertion that the grain-handling
industry understands that grain dusts are included within the terms ''inert, or nuisance
dust."  Judging from the testimony of the witnesses, the term "nuisance
dust" appears to be meaningless to anyone who is not an industrial hygienist.
 As for the term "inert dust," it has two very distinct meanings rather
than a single, commonly understood meaning.  The record shows that industrial
hygienists are alone in their understanding that this term refers to biological inertness.
 The witnesses who were not industrial hygienists understood this term as referring
to chemical inertness and, thus, because grain dusts are not chemically inert, the
standard would apparently exclude rather than include them. Thus, the Secretary failed to
prove that there is any "common understanding" in the grain-handling industry of
the terms "inert or nuisance dust."  At most, the Secretary established an
awareness within the grain-handling industry of the publicity surrounding the Secretary's
attempts to regulate grain dust under the inert or nuisance dust provision of the mineral
dust standard.[[16]]  However, the Constitution requires fair notice of the
requirements of the law, not fair notice of an agency's enforcement position.

Moreover, adoption of the Secretary's interpretation of the inert or nuisance dust
provision would deprive the grain handlers of their due process right to fair notice of
the standard's requirements.  The Secretary's position conflicts with the principle
of regulatory construction that standards are not to be construed in a way that deprives
employers of fair notice.  See Diamond Roofing Co. v . OSHRC , 528
F.2d 645 (5th Cir. 1976).  Cf . Marshall v. Anaconda Co ., 596 F.2d 370
(9th Cir. 1979) (court rejects interpretation of � 1910.179 (b)(2) that raises
"serious question(s) regarding its validity").  As our discussion above
indicates, there is nothing in the mineral dust standard generally, or in the inert or
nuisance dust provision in particular, that places employers on notice that the standard
applies to grain dust.  On the contrary, the manner in which the Secretary adopted
the mineral dust standard deprived employers of any notice they might otherwise have been
given.

In the process of developing the mineral dust standard, the Secretary did not give
even indirect notice of an intent to govern vegetable dusts.  When the ACGIH adopted
its version of Table Z-3, it accompanied its listings with explanatory materials
indicating that at least one set of TLV's, for "'Inert' or Nuisance
Particulates," applied to both mineral and vegetable dusts.  See note 11 supra .
But when the Secretary incorporated these TLV's into 41 C.F.R. � 50-204.50, see note 10 supra ,
he did not incorporate the ACGIH's list of examples and its definitional sections.
 Moreover, when the Secretary later adopted the Walsh-Healey standard as an
established Federal standard under section 6(a) of the Act and repromulgated it as an OSHA
standard, he eliminated any reference to the ACGIH and its TLV's as the indirect source of
the OSHA standard.  As a result, there is absolutely nothing in the OSHA standard to
indicate that any of its provisions apply to organic dusts.  The mineral dust
standard contains no definition of the terms "inert or nuisance dust," no list
of examples, and no other clarifying information.[[17]]

The Secretary nevertheless maintains that we should construe the mineral dust
standard to effectuate the intent of the ACGIH. Deference to the intent of the ACGIH is
not proper here, however, because there was nothing to give the public notice that the
ACGIH's intent was carried over when the Secretary adopted the standard.  It is
axiomatic that OSHA standards must be interpreted in accordance with the natural and plain
meaning of their words; they cannot be construed to mean what the agency may have intended
but did not adequately express.  Diamond Roofing Co. v. OSHRC , 528 F.2d at

649.  See also Bechtel Power Corp. , 85 OSAHRC , 12 BNA OSHC
1509, 1511, 1985 CCH OSHD � 27,381 at p. 35,453 (No. 80-4764, 1985), appeal filed ,
No. 85-7661 (9th Cir. Nov. 27, 1985) (Commission cannot construe a standard "to mean
what it does not say").  Adoption of a strained interpretation of the mineral
dust standard, an interpretation that bears no reasonable relationship to the standard's
plain words, would not serve the purposes of the Act because the standard would not be
effective in guiding the conduct of employers.  See Bethlehem Steel Corp.
v. OSHRC , 573 F.2d 157, 161-162 (3d Cir. 1978); Diamond Roofing Co. v. OSHRC ,
528 F.2d at 650; Lisbon Contractors, Inc ., 84 OSAHRC, 11 BNA OSHC 1971, 1973-74,
1984 CCH OSHD � 26,924 at p. 34,500 (No. 80-97, 1984).  We therefore reject the
Secretary's interpretation of the mineral dust standard and interpret that standard in
accordance with its plain meaning.

II

A

As noted previously, in Docket No. 77-1622 the Secretary also alleged that
Bunge's failure to reduce airborne levels of soybean dust on the fourth floor bin deck and
the shipping gallery violated the crystalline quartz silica provision of the mineral dust
standard.   The judge affirmed this alternative allegation without expressly
discussing the scope of the crystalline quartz silica provision.  However, the judge
implicitly adopted the interpretation that was set forth in the testimony of IH Gribble
and Dr. Thomas A. Richard, the Secretary's two expert witnesses in the field of industrial
hygiene.

According to these witnesses, OSHA does not have a PEL for pure crystalline quartz
silica,[[18]] but rather, the PEL's established in Table Z-3 govern all silica-bearing
dusts, that is, any dust that includes crystalline quartz silica as one of its components.
Accordingly, these witnesses reasoned, the crystalline quartz silica provision applies to
the soybean dust at Bunge's workplace because that dust contained quartz.

The witnesses also testified that the PEL's for inert or nuisance dust and for
crystalline quartz silica are interrelated.  If the number 0 (representing dust with
no quartz in it) is inserted into the crystalline quartz silica formulas, the result is
the PEL's for inert or nuisance dust--15 mg/m3 for total dust and 5 mg/m3 for respirable
dust.  The formulas operate in such a manner as to create a sliding scale of PEL's
depending on the percentage of the total dust or the total respirable fraction of the dust
that is crystalline quartz silica.  In this way, the PEL's are lowered as the
percentage of the silica in the dust becomes higher.  The upper limit of the sliding
scale is the PEL for inert or nuisance dust (containing no quartz); the lower limit is the
PEL for pure quartz dust.

IH Gribble further illustrated the operation of the crystalline quartz silica
provision by describing how he arrived at his conclusion that the PEL's for crystalline
quartz silica at Bunge's workplace on April 27 had been exceeded.  As explained in
Part IA supra , approximately two months after Gribble obtained the three air
contaminant samples during his inspection of Bunge's grain elevator, the samples were
transmitted from OSHA's New Orleans Area Office to OSHA's testing laboratory in Salt Lake
City.  There, lab chemist John C. Germ conducted an x-ray diffraction analysis on the
samples.  Based on his analysis, Germ concluded that each sample contained
crystalline quartz silica.  The x-ray diffraction analysis also resulted in a
quantitative determination as to the amount of quartz in each of three samples.
 Specifically, Germ determined the amount of crystalline quartz silica as a
percentage of the total weight of the dust collected on the filter.  He recorded the
following quantitative results:

Filter 030 (shipping gallery, total dust)
        2.4% quartz

Filter 044 (bin deck, respirable dust)
           3.5% quartz

Filter 051 (bin deck, total dust)

4.6% quartz

At the hearing, Germ acknowledged that x-ray diffraction analysis should not be
used to analyze total dust samples.  On the standardized forms on which he had
recorded his analytical results, printed in such a manner that it cannot be overlooked,
was the following notation:

OSHA X-ray Si02 Procedure.  This X-ray analysis is accurate only for
respirable samples of (less than 10 micrograms) diameter. Nonrespirable samples should be
analyzed colorimetrically by P & CAM 106.

Shown this standardized notation, Germ did not deny that x-ray diffraction
analysis was considered by OSHA itself to be an inaccurate method of analyzing total dust
samples.[[19]]  Instead, he testified to the effect that he had relied on the results
of his analysis of the total dust samples only to corroborate the results of his analysis
of the respirable dust sample (filter 044).

Nevertheless, IH Gribble used these results to compute the PEL's for both
respirable crystalline quartz silica and total crystalline quartz silica at Bunge's
workplace on April 27.  First, Gribble looked to the two formulas in Table Z-3 that
are used to determine the PEL's for respirable crystalline quartz silica and for total
crystalline quartz silica.  According to the witness, the notations "%
Si02" and "% S202" (apparently a typographical error) refer to the
percentage by weight of the total dust collected (i.e., either all dust in the employee's
breathing zone or all respirable dust) that is crystalline quartz silica.  Here,
these were the figures supplied by lab chemist Germ, i.e., 2.4%, 3.5%, and 4.6%.
 Using these figures, Gribble calculated the controlling PEL'S.[[20]]  Gribble's
next step was to compare each employee's 8-hour time weighted average (TWA) exposure with
that employee's corresponding PEL. According to Gribble, the relevant exposure for
purposes of this comparison was the previously-determined 8-hour TWA exposure for either
all dust or all respirable dust in the employee's breathing zone, which in this case
measured the amounts of soybean dust (total or respirable) to which the three employees at
issue were exposed on April 27.  Upon making these comparisons, Gribble concluded
that in each instance the applicable PEL had been exceeded.[[21]]

In his decision, Judge Oringer credited the Secretary's evidence on the meaning of
the crystalline quartz silica provision and the percentage of quartz in the Bunge
samples.  He found that all three of the Bunge employees whose exposures were sampled
had been exposed to levels of quartz-bearing dust in excess of the mineral dust standard's
PEL's for total and respirable crystalline quartz silica.  He also found that Bunge
had failed to implement feasible engineering controls to reduce the dust levels within
permissible limits.  Accordingly, he sustained the Secretary's alternative charge
under the crystalline quartz silica provision of the mineral dust standard.

On review, Bunge argues that the judge erred in affirming the alleged violation of
the crystalline quartz silica provision.  Bunge suggests that the judge's
interpretation and application of this provision may have been erroneous.  In any
event, it contends that the provision cannot be interpreted and applied as the Secretary
and the judge have done without depriving grain handlers of their due process rights to
fair notice of the standard's requirements.

Bunge raises two fair notice issues in support of its claim that "this
virtually indecipherable regulation does not pass constitutional muster."  
First, it argues that the provision is unenforceably vague because the employer cannot
tell whether it is in compliance with the regulation.  Bunge notes Gribble's
testimony concerning his calculations of over-exposure and asserts that there is nothing
in the mineral dust standard or its crystalline quartz silica provision that gives notice
that the PEL, once calculated, should be compared with the 8-hour TWA exposure for all of
the dust collected in the sample, including both the organic and inorganic components of
the dust.

The second fair notice issue is related to st it
is error to treat it as nuisance dust when considering a [crystalline quartz] silica
violation."

B

We have already concluded that the mineral dust standard applies only to
mineral dusts.  Because it is undisputed that soybean dust is not a mineral dust, the
crystalline quartz silica provision of the mineral dust standard cannot be applied to the
cited conditions. Accordingly, this alternative allegation in Docket No. 77-1622 must also
be vacated.

In reaching this conclusion, we are guided by the principle that two related
provisions of single standard must be interpreted in the context of the standard as a
whole.  See State Highway Commission of Missouri v. Volpe ; 2A
Sutherland Statutory Construction � 46.05.  It would be inconsistent for us to
hold that the inert or nuisance dust provision does not apply to soybean dust, while the
crystalline quartz silica provision of the same table does apply to soybean dust.  
Bunge cites to the testimony of the Secretary's witnesses that the PEL's for inert or
nuisance dust and for crystalline quartz silica, as they are interpreted by the Secretary,
are in effect PEL's for nuisance dust containing quartz.  Therefore, since the PEL's
for inert or nuisance dust do not apply to soybean dust, the formulas for reducing those
PEL's when quartz is present in the dust also do not apply.

We find considerable merit in Bunge's analysis.  However, we also observe
another fundamental inconsistency in attempting to apply the crystalline quartz silica
provision to grain dust.  We vacate the nuisance dust allegation on ground that the
inert or nuisance dust PEL's are set forth in a table that applies only to mineral
dusts.  The crystalline quartz silica PEL's are included in the same table, Table
Z-3.  The mineral dust standard does not give fair notice that its inert or nuisance
dust provision applies to a dust that is predominantly organic.  We find the same
notice problem in applying a different provision of the same standard to the same dust.
Since Table Z-3 is limited in its coverage to mineral dusts, we conclude that none
of the provisions of the mineral dust standard can be applied to soybean dust.

We also agree with Bunge's argument that the Secretary's interpretation of the
crystalline quartz silica provision deprives grain handlers of their due process rights to
fair notice of the standard's requirements.  We note that, in contrast to the inert
or nuisance dust allegation, there is not even a claim by the Secretary of a common
understanding that the crystalline quartz silica PEL's are applicable to grain dust. 
Certainly, the Secretary cannot rely on any publicity surrounding his enforcement
position, for this appears to be the first and only effort to apply this provision to this
type of dust.[[22]]  In fact, we are unaware of any other enforcement action where
the Secretary sought to apply the crystalline quartz silica provision to a dust that was
not wholly, or at least predominantly, silica dust.  Nor is there any legislative
history to support the Secretary's interpretation of this provision.  The 1968
ACGIH-TLV's pamphlet, which is the source document, provides no more guidance on
the meaning and application of the crystalline quartz silica provision than does the OSHA
mineral dust standard itself.  Neither the standard, the source document, nor any
other written materials that we are aware of explains the Secretary's interpretation and
application of the provision.  Indeed, our only information on these matters is the
testimony of IH Gribble and Dr. Richard.

We are left then with the language of the standard, which Bunge correctly
characterizes as "virtually indecipherable."  The standard states that
"exposure to any material listed in Table Z-3" shall not exceed the PEL's
"given for that material in the table."  The "material" that is
listed is crystalline quartz silica and the table in which it is listed is captioned
"Mineral Dusts."  To begin with, we could not reasonably expect that an
employer looking through the Secretary's standards to find the PEL's for grain dust would
read the table and conclude that it had found the applicable PEL's.

Even if the employer made it over this initial hurdle, it would have considerable
difficulty in determining whether it had exceeded the PEL's.  It would have to guess
the meaning of the notations "% Si02" and "% S202 in the two formulas for
determining the PEL's.  Is one of them a typographical error or do they refer to two
different substances?  Do they refer to all silica in the sample or just the silica
that is crystalline quartz?  The employer would then have to decide whether to state
the percentages as whole numbers (as the witnesses did) or as their decimal equivalents
(as is more common in performing mathematical computations).   Finally, once the
employer calculated the PEL's, it would have to recognize that, contrary to the language
of the standard, those PEL's do not govern the amounts of total quartz or respirable
quartz in the air but rather the amounts of total dust or respirable dust, including both
the organic and inorganic components of the dust.  In view of these many
uncertainties and ambiguities, we conclude that a reasonable employer in the
grain-handling industry would not understand from reading the crystalline quartz silica
provision of the mineral dust standard that it is to be interpreted and applied in the
manner described by the Secretary's witnesses.  The provision as applied to the facts
of this case does not give fair notice of its requirements.[[23]]

III

The separate citations in Docket Nos. 78-0838 and 78-2213 allege violations
of 29 C.F.R. �� 1910.1000(c) and (e), based on the provision of section 1910.1000 that
has been referred to throughout this decision as "the inert or nuisance dust
provision" of the "mineral dust standard."  Neither case involves any
allegation under the crystalline quartz silica provision of the mineral dust
standard.[[24]]  No hearing has been held in either case.  Instead, the
Secretary and Bunge entered into stipulated settlement agreements.  The two
agreements are essentially identical.   The key provision of both agreements, as it
is stated in the agreement filed in Docket No. 78-0838, provides:

Whereas each of the parties herein have spent a substantial amount in the
preparation and trial of OSHRC Docket No. 77-1622 . . . ; and whereas the identical issue
is presented herein; the parties therefore stipulate and agree to be bound by the highest
decision rendered in OSHRC Docket No. 77-1622, whether by the Occupational Safety and
Health Review Commission, the United States Court of Appeals, or the United States Supreme
Court, so that if grain dust ultimately is held to be a nuisance dust . . . within the
meaning of . . . Table Z-3......, this matter shall be heard on the merits, and if grain
dust ultimately is not held to be a nuisance dust . . . . this matter shall be dismissed.

After issuing his decision in Docket No. 77-1622, Judge Oringer issued separate decisions
in Docket Nos. 78-0838 and 78-2213.  In both of these cases, he concluded that the
issues were ripe for decision.  Accordingly, he applied his holding in Docket No.
77-1622 and vacated the citation items in the two later cases on the ground that the inert
or nuisance dust provision does not apply to employee exposure to grain dust.  On
review, the Secretary argues, and Bunge agrees, that the judge acted prematurely in
vacating in citation items at issue in Docket Nos. 78-0838 and 78-2213.  The parties
contend that the judge erred in failing to wait for "the highest decision rendered in
OSHRC Docket No. 77-1622" within the meaning of their settlement agreements.

We disagree.  Judge Oringer acted properly in taking action to remove these
two cases from this docket.  In addition, the parties have not been prejudiced as a
result of the judge's action.  By deciding these three cases as a consolidated unit,
we have accomplished the result the parties sought to achieve through their settlement
agreement.  The inert or nuisance dust provision has been uniformly applied in all
three cases, and all three cases remain open if our decision is appealed.

Accordingly, we review the merits of the judge's rulings on the contested citation
items in Docket Nos. 78-0838 and 78-2213.  For the reasons stated previously, we
agree with the judge that the citation items must be vacated because inert or nuisance
dust provision of the mineral dust standard does not apply to employee exposure to grain
dust.

IV

In Docket No. 77-1622, the judge's decision is affirmed with respect to the
allegations under the inert or nuisance dust provision and reversed with respect to the
allegations under the crystalline quartz silica provision.  In Docket Nos. 78-0838
and 78-2213, the judge's decisions are affirmed.  All citation items at issue on
review in this consolidated proceeding, including alternative allegations, are vacated.

FOR THE COMMISSION

Ray H. Darling, Jr.

Executive Secretary

Dated:  April 22, 1986

The Administrative Law Judge decision in this matter is unavailable in this
format.  To obtain a copy of this document, please request one from our Public
Information Office by e-mail ( [email protected]
), telephone (202-606-5398), fax (202-606-5050), TTY (202-606-5386).

FOOTNOTES:

[[1]] The term "mineral dust standard" will be used throughout this
decision to refer to various related provisions of 29 C.F.R. �1910.1000 that, taken
together, require employers to implement protective measures whenever their employees are
exposed to mineral dust levels that exceed any of the permissible exposure limits
("PEL's") listed in Table Z-3 of �1910.1000.  "Inert or nuisance
dust" is one of the listed substances that is regulated under the mineral dust
standard.  The pertinent provisions of �1910.1000 are the following:

�1910.1000 Air contaminants.

An employee's exposure to any material listed in Table Z-1, Z-2, or Z-3 of this
section shall be limited in accordance with the requirements of the following paragraphs
of this section.

(c) Table Z-3:  An employee's exposure to any material listed in Table Z-3,
in any 8-hour work shift of a 40-hour work week, shall not exceed the 8-hour time weighted
average limit given for that material in the table.

TABLE Z-3 -- MINERAL DUSTS

Substance

Mg/M3

Inert or Nuisance Dust:

Respirable fraction ............5mg/M3

Total dust .........................15mg/M3

(e) To achieve compliance with paragraph (a) through (d) of this section, administrative
or engineering controls must first be determined and implemented whenever feasible.  
When such controls are not feasible to achieve full compliance, protective equipment or
any other protective measures shall be used to keep the exposure of employees to air
contaminants within the limits prescribed in this section. . . . Whenever respirators are
used, their use shall comply with � 1910.134.

[[2]] "Crystalline quartz silica" is another substance that is regulated
under the "mineral dust standard."  In addition to containing the PEL's for
"inert or nuisance dust," Table Z-3 of � 1910.1000 also sets forth the
following PEL's for "crystalline quartz silica":

TABLE Z-3 -- MINERAL DUSTS

Substance
*
Mg/M3

Silica:

Crystalline:

10 mg/M3

Quartz (respirable) .........
*
% SiO2 + 2

Quartz (total dust) ..........
*
30 mg/M3

% S2O2 [sic] + 2

[[3]] Bunge presents three challenges to the propriety of the Secretary's enforcement
procedures in Docket No. 77-1622.  First, it argues that, contrary to the
requirements of � 8(a)(2) of the Act, 29 U.S.C. � 657(a)(2), the underlying inspection
was not conducted "within reasonable limits and in a reasonable manner."  
More specifically, it contends that the inspection was unreasonable because the air
contaminant samples taken by the Secretary were obtained under conditions that were not
representative of the conditions that usually existed at its workplace.  Bunge also
argues that the judge erred in granting two motions by the Secretary to amend the
allegations of violation contained in the citation.  Finally, Bunge charges that,
during the period between the filing of its notice of contest and the beginning of the
hearing, the Secretary engaged in a series of misrepresentations and abuses of procedure
that in combination "subverted the Act's fundamental process."  According
to Bunge, the Secretary thereby deprived it of the administrative and procedural due
process guaranteed to it by law.

[[4]] Total dust samples collect all dust in the breathing zone, i.e., they are
"nonspecific."  Respirable dust samples are also "nonspecific" in
the sense of capturing any kind of particulate material in the air.  However, they
are designed to collect only respirable particles, which are 10 microns or less in
length.  This size separation occurs when a device called a "cyclone" is
used in conjunction with the sampling device.

[[5]] The samples were taken in the breathing zones of three Bunge employees.
  A sampling device containing a filter was placed on Lionel McZeal while he worked
on the shipping gallery.  The filter collected 5.81 mg of total dust.  Using
this figure in conjunction with other relevant data, IH Gribble calculated McZeal's 8-hour
time weighted average (TWA) exposure to be 8.06 mg/M3. McZeal's exposure was therefore
within the limits established for total inert or nuisance dust, that is, it was less than
the 15 mg/M3 PEL set forth in Table Z-3.  A second sampling device with a cyclone
attached so that only respirable dust would be collected was placed on Rickie Cure as he
worked on the fourth floor bin deck.  The filter collected 9.96 mg of respirable
dust.  Cure's 8-hour TWA exposure was calculated to be 12.14 mg/M3.  Thus,
Cure's exposure exceeded the 5 mg/M3 PEL for respirable inert or nuisance dust.  The
third sampling device was placed on Joseph Charles while he worked on the fourth floor bin
deck.  The filter collected 18.94 mg of dust (total dust).  The 8-hour TWA
exposure for Charles was calculated to be 26.05 mg/M3.  This exposure exceeded the 15
mg/M3 PEL for total inert or nuisance dust.

[[6]] The Secretary charged a violation of the mineral dust standard on the
shipping gallery based solely on the sampling of McZeal's exposure, which did not
establish a violation of the inert of nuisance dust provision of the cited standard.
  See note 5 supra .  There is no explanation in the record for this
anomaly.

[[7]] The third and final lab analysis was conducted several months later,
apparently for the purpose of reconciling the conflict between the first two analyses.
  On November 15, lab chemist Dixon conducted a second petrographic analysis on one
of the samples.  This analysis confirmed Germ's report that crystalline quartz silica
was present in the sample.  Dixon was unable to make a quantitative determination.
  At the hearing, Dixon testified that various treatments of the sample between June
27 and November 15 had removed almost all of the material on the filter "and just
about everything I saw at that point was quartz."  Dixon hypothesized that the
crystalline quartz silica he saw on November 15 had been in the sample all along, but that
he had been unable to see it on June 27 because of the "interference" of an
organic "coating."  In his opinion, when this coating was removed,
primarily through "chemical ashing" (treatment with phosphoric acid), he was
able to see the quartz and confirm its presence in the sample.

[[8]] The "A.C.G.I.H." is the American Conference of Governmental
Industrial Hygienists.  As discussed more fully infra , its "TLV
Committee" drafted the standard that was the indirect source of the mineral dust
standard.  It appears from the source document that "Herbert E. Stokinger,
Ph.D.," was the chairman of the committee that drafted the standard.  See Exh.
J-1 (for judicial notice) at page 26.  In addition, a second ACGIH publication
introduced into the record as Exh. J-2 (for judicial notice) lists "Herbert E.
Stokinger, Ph.D." as a member of the "1977 TLV Airborne Contaminants
Committee."  The record does not otherwise identify Stokinger or elaborate on
the telephone conversation with him.

[[9]] On February 2, 1978, approximately three weeks before the hearing in Docket
No. 77-1622, OSHA issued Program Directive #300-11, which expressly cancelled the July 13
Wilson-Tice memo.  In this document, which was signed by the same Deputy Director
Wilson, OSHA interpreted the Table Z-3 PEL's for inert or nuisance dust as applying to all
types of nuisance dust, both organic and mineral, and as specifically including soybean
dust.

[[10]] 29 C.F.R. � 1910.1499 identifies the source of � 1910.1000 (including the
mineral dust standard) as 41 C.F.R. � 50-204.50. This was a standard originally issued
under the Walsh-Healey Act and later adopted as an "established Federal
standard" under � 6(a), 29 U.S.C. � 655(a), of the Occupational Safety and Health
Act.  In turn, the Walsh-Healey standard was largely based on a non-governmental
consensus standard developed by the ACGIH (American Conference of Governmental Industrial
Hygienists).  In particular, the mineral dust PEL's established under 41 C.F.R. �
50-204.50 (and later published in Table Z-3 of � 1910.1000) were derived from an ACGIH
pamphlet titled Threshold Limit Values of Air-borne Contaminants (sic) for 1968: 
Recommended and Intended Values (hereafter " 1968 ACGIH-TLV's ").

We note that the terms "threshold limit value (TLV)" and
"permissible exposure limit (PEL)" are often used interchangeably. However,
there is a difference in their meaning.  As stated in the preface to the 1968
ACGIH-TLV's pamphlet, a TLV is an airborne concentration of a substance that
represents the level at "which it is believed that nearly all workers may be
repeatedly exposed, day after day, without adverse effect."  The nature of this
adverse effect "may differ from substance to substance; protection against impairment
of health may be the guiding factor for some, whereas reasonable freedom from irritation,
narcosis, nuisance or other forms of stress may dominate the basis for others."
  The TLV is "based on the available information from industrial experience,
from experimental human and animal studies, and when possible, from a combination of the
three."

Thus, "TLV" is an industrial hygienist's term and, as the ACGIH
explained, the limits "are intended for use in the field of industrial hygiene."
  In contrast, "PEL" is a legal term referring to a limit that may not be
exceeded or a limit that triggers certain legal obligations when it is exceeded.  
When the Secretary of Labor incorporated the TLV's developed by the ACGIH into his
occupational health standards, he thereby transformed the TLV's into legally enforceable
PEL's.

[[11]] The 1968 ACGIH-TLV's pamphlet refers to "'Inert' or Nuisance
Particulates" and sets forth a list of "Some 'Inert' or Nuisance
Particulates" in its appendix.  The list includes both organic and inorganic
substances and both mineral and vegetable dusts.  For example, four of the components
of grain dust are included on the list--calcium carbonate, cellulose, starch and sucrose.
However, neither grain dust generically nor any particular type of grain dust is included
on the list.  The pamphlet also contains a section in the preface that explains the
terms "'Inert' or Nuisance Particulates."  This section similarly refers to
both organic and inorganic substances as examples.  The Secretary also introduced
into the record the 1977 version of the ACGIH pamphlet, which was the most recent version
at the time of hearing.  That pamphlet similarly includes a list of particulates and
an explanatory section that indicate an intent to include organic dusts within the
coverage of the TLV's.

[[12]] The same rules of interpretation are applicable in interpreting both statutes and
administrative regulations, such as the Secretary's occupational safety and health
standards.  See , e.g ., Ohio-Sealy Mattress Mfg. Co ., 83 OSAHRC
27/C14, 11 BNA OSHC 1377, 1380-1381, 1983-84 CCH OSHD � 26,528, p. 33,805 (No. 79-5600,
1983).

[[13]] Lab chemist Dixon, who was accepted by the judge as an expert witness in
mineralogy, outlined the principal subcategories of silica.  The two basic types are
crystalline silica, which is commonly called "free silica," and amorphous
silica, which is not crystalline and therefore not classified scientifically as a mineral.
  Amorphous silica includes two subcategories--diatomaceous earth and dehydrated
silica gel.  Free silica exists as quartz (i.e., crystalline quartz silica),
tridymite, cristobalite, coesite and stishovite.  1 PATTY'S INDUS. HYGIENE &
TOXICOLOGY 185 (G.D. Clayton & F.E. Clayton 3d rev. ed. 1978)  Each of these
last-mentioned substances is a "polymorph" of free silica, that is, each is a
mineral that has the chemical formula "Si02".  Quartz is the most common of
these substances, not only in nature but also in occupational environments.

[[14]] Lab chemist Dixon stated that three of the substances listed in Table Z-3
are not classified scientifically as "minerals": amorphous silica because it is
not crystalline, Portland cement (a silicate) because it does not occur in nature, and
coal dust because coal is organic.  We assume that this testimony accurately
describes how a mineralogist would classify the substances.  Nevertheless, it is
clear on this record that all of the substances in Table Z-3 are considered to be
"mineral dusts" under the common usage of the term "mineral."  
Even the Secretary's witnesses admitted this fact.  For example, IH Gribble testified
that all of the Table Z-3 substances are mineral dusts with the exception of coal
dust.  Even coal, he conceded, is "termed by many to be a mineral because it's
mined from the ground."  Dr. Richard gave similar testimony.  With respect
to coal dust, he stated that coal is considered to be a "natural mineral
deposit" despite its organic composition.

[[15]] At the hearing, Dr. Thomas J. Culpepper, a witness for Bunge who was found
to be an expert in environmental analytical chemistry, testified that the term
"inert" to a chemist means nonreactive.  For this reason, he concluded that
organic dusts such as grain dusts would not be classified as inert or nuisance dusts.

[[16]] The Secretary introduced various exhibits, as well as the testimony of
industrial hygienist Gribble and Dr. Richard, showing that, prior to the instant citation
against Bunge, both federal and state officials had issued citations to several grain
handlers for dust levels exceeding the inert or nuisance dust PEL's.  The Secretary
also proved that his enforcement actions had been publicized both in trade journals and in
a magazine published by OSHA.  In his brief to the Commission, the Secretary cites
this evidence as proving that the term "nuisance dust" is commonly understood
within the grain-handling industry as including grain dust.  He cites no other
evidence in support of that proposition.

[[17]] We further observe that, even if an employer were aware of the standard's
ACGIH precursors, it would be very difficult for him to discover the intent of the ACGIH
in developing its TLV's for inert or nuisance dust.  At the hearing, IH Gribble
testified that it had been difficult for him--a professional industrial hygienist and a
member of the ACGIH--to obtain a copy of the 1968 pamphlet so that he could review the
ACGIH's explanatory sections.  Certainly today it would be even more difficult for an
employer engaged in grain handling to obtain a copy.  Under these circumstances, it
would be unreasonable to expect employers to refer to source materials, and especially
these ACGIH source materials, outside of the OSHA standard itself in order to give to the
standard's terms a meaning that is contrary to their commonly understood meaning.

[[18]] According to the witnesses, PEL's for pure crystalline quartz silica can be
determined by inserting the number 100 (representing 100% quartz) into the two formulas
set forth in the mineral dust standard.  See note 2 supra .

[[19]] Even if we were to conclude that the mineral dust standard applied to grain
dust containing silica, we could not sustain the citation with respect to the allegation
that total dust levels exceeded the PEL's for crystalline quartz silica, since those
allegations rest solely on Germs X-ray diffraction analysis of filters 030 and 051.

[[20]] Gribble further testified that the formulas refer to whole number
percentages rather than their decimal equivalents, e.g., 2.4 rather than .024.  Thus,
Gribble inserted the number 3.5 into the respirable dust formula to obtain a respirable
dust PEL of 1.81 mg/M3 for the fourth floor bin deck.  He inserted the numbers 2.4
and 4.6 into the total dust formula to obtain total dust PEL's of 6.82 mg/M3 and 4.54
mg/M3 for the shipping gallery and the fourth floor bin deck, respectively.

[[21]] At the hearing, Gribble in effect conceded that no charge should have been
made with respect to crystalline quartz silica on the shipping gallery.  Gribble
referred to guidelines set forth in an OSHA Industrial Hygiene Manual, although he did not
state which edition of the manual or which section he was referring to.  Under those
guidelines, as described by the witness, once he had determined the applicable PEL, he
should then have adjusted it by multiplying the PEL by the "statistical correction
factor."  This adjustment is made to take into account the possibility of error
in the collection of the sample and in the laboratory determination of the percentage of
crystalline quartz silica.  It accomplishes this goal by increasing the PEL to add in
a margin of error.  Gribble also testified that, for a total dust sample, the
statistical correction factor was 1.25.  Thus, the adjusted PEL for total crystalline
quartz silica on the shipping gallery was 8.5 mg/M3 (1.25 x 6.82).  Since Lionel
McZeal's 8-hour TWA exposure was only 8.06 mg/M3, exposure to excessive dust levels was
not established under the Secretary's internal guidelines.

[[22]] At the hearing, the Secretary's counsel stated that, to the best of his
knowledge, this was the first time a granary had ever been charged with a violation of
this provision.  In addition, the two lab chemists who analyzed the Bunge samples
indicated that they were probably the first grain dust samples the Salt Lake City testing
laboratory had ever analyzed for silica content.  While these chemists further
testified that similar analyses were conducted after the analysis of the Bunge samples, we
are unaware of any subsequent citation of a grain handler under the crystalline quartz
silica provision.

[[23]] Indeed, we are not persuaded that the Secretary's interpretation and
application of the crystalline quartz silica provision is consistent with the intent of
the ACGIH, which drafted the source TLV's.  Although IH Gribble and Dr. Richard gave
consistent testimony to the effect that the PEL's cover all silica-bearing dusts, neither
cited any document stating that the PEL's should be applied to predominantly organic dusts
such as grain dust.  There is certainly nothing in the ACGIH source document that
supports this conclusion.

More importantly, however, we are unable to conclude that application of the
crystalline quartz silica provision to grain dust would have the effect intended by the
ACGIH.  Based on the ACGIH's explanation of how it develops its TLV's, it appears
likely that the TLV's for crystalline quartz silica were primarily designed to protect
employees from fibrotic changes to the lung, including specifically the risk of
contracting silicosis.  Yet, the documentary evidence presented by the Secretary
suggests that it is virtually impossible to contract silicosis through exposure to grain
dust.

In particular, we note the epidemiological survey and research study admitted into
evidence as Secretary's Exhibit B.  Williams, Skoulas & Merriman, Exposure to
Grain Dust:  I.  A Survey of the Effects , 6 J. OCCUP. MED. 319 (Aug. 1964)
(hereafter Williams ).  Significantly, these researchers observed that, with
the exception of a single case reported in 1944, "there has been no report in the
literature supporting the possibility that free silica in grain dust might be a factor in
the resultant respiratory disease." Williams at p. 320.  Indeed, these
researchers unequivocally expressed their opinion that free silica is not a factor:

The dust analyses indicate that most of the free silica is in the soil fraction of
the dust.  It is known that lifetime exposure to the dust of desert sands does not
lead to the development of silicosis.  Likewise, there is no evidence that the free
silica in soil dust can produce the disease.  It is unlikely that the very small
amount of free silica in the organic fraction could produce silicosis.   Moreover,
the silica is closely bound physically to the organic material and there is none of the
crushing or grinding of silicious material which creates a silicosis hazard. 
Therefore . . . there is strong evidence against silica playing any role in the
respiratory disease associated with exposure to grain dust.  Williams at p. 326.
  In the absence of any reason to believe that the quartz within grain dust creates
any hazard whatsoever, we cannot conclude that the Secretary's interpretation of the
crystalline quartz silica provision serves the purpose intended by the ACGIH.

[[24]] Also at issue in Docket No. 78-2213 are alleged violations of two
subsections of 29 C.F.R.� 1910.134.  Because these requirements are incorporated by
reference into the mineral dust standard--specifically, the last sentence of
�1910.1000(e)--the parties agree that they can be applied to the cited working conditions
only if the inert or nuisance dust provision can be applied to those conditions.