SENCO PRODUCTS, INC.

OSHRC Docket No. 79-3291

Occupational Safety and Health Review Commission

October 29, 1982

[*1]

Before: ROWLAND, Chairman; CLEARY and COTTINE, Commissioners.

COUNSEL:

Council for Regional Litigation, Office of the Solicitor, USDOL

William S. Kloepfer, Associate Regional Solicitor, USDOL

John M. Kunst, Jr. and Kent W. Seifried, for the employer

OPINION:

DECISION

BY THE COMMISSION:

This case is before the Commission for review under section 12(j), 29 U.S.C. 661(i), of the Occupational Safety and Health Act of 1970, 29 U.S.C. 651-678 ("the Act"). Before a hearing on the merits, Administrative Law Judge George Taylor granted Respondent's ("Senco") motion to dismiss, holding that the standard under which Senco was cited had been improperly promulgated. We reverse Judge Taylor's decision and remand for further proceedings consistent with this decision.

I

In May 1979, a compliance officer of the Occupational Safety and Health Administration ("OSHA") inspected the Senco workplace. As a result of the inspection, the Secretary of Labor ("Secretary") issued a citation alleging that several Senco employees were exposed to a mixture of methyl ethyl ketone, xylene and acetone at levels that exceeded the applicable limit for a mixture of these air contaminants specified in 29 C.F.R. 1910.1000(d)(2)(i). [*2] n1

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n1 29 C.F.R. 1910.1000(d)(2)(i) provides:

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.

* * *

(d) Computation formulae:

* * *

(2)(i) In case of a mixture of air contaminants an employer shall compute the equivalent exposure as follows:

Em = (C[1] / L[1] + C[2] / L[2]) + . . . (C[n] / L[n])

Where:

Em is the equivalent exposure for the mixture.

C is the concentration of a particular contaminant.

L is the exposure limit for that contaminant, from table Z-1, Z-2, or Z-3.

The value of Em shall not exceed unity (1).

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The history of section 1910.1000 is crucial to an understanding of this case. The Secretary promulgated section 1910.1000, originally codified at 1910.93, pursuant to section 6(a) of the Act. n2 Section 1910.1000 was based on an established Federal standard, 41 C.F.R. 50-204.50, promulgated under the Walsh-Healey [*3] Public Contracts Act (41 U.S.C. 35-45). See 29 C.F.R. 1910.1499; see also 36 Fed. Reg. 10523 (May 29, 1971). The Walsh-Healey standard, section 50-204.50, n3 referred to the pamphlet entitled "Threshold Limit Values ("TLV") of Airborne Contaminants for 1968" of the American Conference of Governmental Industrial Hygienists ("ACGIH"). The OSHA standard promulgated May 29, 1971 was very similar to the Walsh-Healey standard's references to the ACGIH pamphlet, except that the OSHA standard referred to the 1970 ACGIH TLVs rather than the 1968 ACGIH TLV's. Moreover, unlike the Walsh-Healey standard's reference to the ACGIH pamphlet, the OSHA standard explicitly set forth the substances listed in the ACGIH booklet and the TLVs for these substances. The TLVs were those listed in the 1970 ACGIH booklet rather than the 1968 version.

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n2 Section 6(a) provides, in pertinent part, that:

Without regard to chapter 5 of Title 5 or to other subsections of this section, the Secretary shall, as soon as practicable during the period . . . ending two years after [the effective date of the Act] . . . by rule promulgate as an occupational safety or healthe standard any national consensus standard, and any established Federal standard, unless he determines that the promulgation of such a standard would not result in improved safety or health for specifically designated employees. . . .

According to section 3(10) of the Act, an established Federal standard is "any operative occupational safety and health standard established by an agency . . . or contained in any Act of Congress. . . ."

n3 The pertinent portions of section 50-204.50 are quoted in the text infra.

[*4]

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Neither the Walsh-Healey standard nor the May OSHA standard specifically referred to the mixtures provision contained in an appendix to the ACGIH table of TLVs. n4 In August 1971, the Secretary repromulgated section 1910.1000 after revision "in the interest of greater intelligibility and accuracy." n5 This repromulgated standard did not refer to any ACGIH publication but instead contained tables listing specific substances and their TLVs. Most of the TLVs were taken from the 1968 ACGIH table. Additionally, the repromulgated standard now explicitly set forth the mixtures provisions pertinent to this case. The new mixtures section provided,

An employee's exposure to any material listed in table G-1 . . . shall be limited in accordance with the requirements of the following paragraphs of this section.

* * *

(d) Computation formulae:

* * *

(2)(i) In case of a mixture of air contaminants an employer shall compute the equivalent exposure as follows:

Em = C[1] / L[1] + C[2] / L[2] + . . . C[n] / L[n]

Where:

Em is the equivalent exposure for the mixture.

C is the concentration of a particular [*5] contaminant.

L is the exposure limit for that particular contaminant, from table Z-1, Z-2, or Z-3.

The value of Em shall not exceed unity (1).

(Emphasis added)

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n4 The mixtures provision in the appendices of both the 1968 and 1970 ACGIH pamphlets stated:

When two or more hazardous substances are present, their combined effect, rather than that of either individually, should be given primary consideration. In the absence of information to the contrary, the effects of the different hazards should be considered as additive. That is, if the sum of the following fractions,

C1 / T1 + C2 / T2 + -- CN / Tn

exceeds unity, then the threshold limit of the mixture should be considered as being exceeded. . . .

Exceptions to the above rule may be made when there is good reason to believe that the chief effects of the different substances are not in fact additive, but independent as when purely local effects on different organs of the body are produced by the various components of the mixture. In such cases the threshold limit ordinarily is exceeded only when at least one member of the series

(C1 / T1 + or + C2 / T2 etc.)

itself has a value exceeding unity. . . .

(Emphasis added)

n5 See 36 Fed. Reg. 15101 (Aug. 13, 1971).

[*6]

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II

In promulgating standards under section 6(a) of the Act, the Secretary was not required to adopt the the source standards verbatim but he was not empowered to make substantive changes from the source standards. George C. Christopher & Sons, 82 OSAHRC   , 10 BNA OSHC 1436, 1443, 1982 CCH OSHD P25,956 at p. 32,531 (No. 76-647, 1982). Senco argues that the mixtures provision under which it was cited was not a part of the Walsh-Healey standard, section 50-204.50, and therefore its inclusion in section 1910.1000 represents a substantive change from the source standard.

Senco also asserts that the standard is invalid if its source is considered to be the ACGTH document. The company contends that the ACGIH document is not an established federal standard or national consensus standard and therefore could not have been validly adopted under section 6(a) of the Act. Senco also contends that there are substantive differences between the mixtures provision in section 1910.1000 and the ACGIH document. The OSHA mixtures provision, unlike the corresponding provision in the ACGIH document, is mandatory [*7] rather than advisory, and it also omits a specific exception for non-additive substances contained in the ACGIH mixtures provision. These changes, according to Senco, are substantive because they place different and more stringent obligations upon employers.

The Secretary contends that the source of section 1910.1000 was the Walsh-Healey standard and that the alterations made to the standard were insubstantial. The Walsh-Healey standard and the current standard essentially impose the same obligations on the employer. In making this contention, the Secretary points to several cases, including Deering Milliken, Inc., 78 OSAHRC 101/A2, 6 BNA OSHC 2143, 1978 CCH OSHD P23,191 (No. 12597, 1978), aff'd, 630 F.2d 1094 (5th Cir. 1980), in which the courts and the Commission have found certain changes in source standards to be insubstantial. n6

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n6 We reject the Secretary's argument that Senco may not challenge the procedural validity of an OSHA standard in an enforcement proceeding. In Rockwell International Corp., 81 OSAHRC 118/A2, 9 BNA OSHC 1092, 1980 CCH OSHD P24,979 (No. 12470, 1980), the Commission held that the employer can raise such a challenge. We adhere to that holding. See George C. Christopher & Sons, supra.

[*8]

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III

In granting Senco's motion to dismisse, Judge Taylor held that the source of the mixtures provision was the ACGIH document and concluded that the mandatory nature of the mixtures provision in section 1910.1000 represented a substantive change from the advisory nature of the corresponding provision in the ACGIH document. However, we conclude that the source of section 1910.1000 was the Walsh-Healey standard, not the ACGIH document. See Chlorine Institute v. OSHA, 613 F.2d 120 (5th Cir. 1980). The May promulgation explicitly stated that the basis for the OSHA air contaminant standard was an earlier Walsh-Healey standard. See 36 Fed. Reg. 10523. In the explanation to the August repromulgation, OSHA did not say it was based on the Walsh-Healey Act, but the stated purpose was to clarify the earlier standard. Also, 29 C.F.R. 1910.99 set forth the source standard for 1910.93 and continued to identify the source as 41 C.F.R. 50-204.50. See 29 C.F.R. 1910.1499. Therefore, the basis of the repromulgated standard remained the Walsh-Healey standard.

While it is clear that the Walsh-Healey [*9] standard is the basis of the current OSHA standard, it is less clear what the original Walsh-Healey standard contained. Senco argues that the OSHA standard is invalid because it contains a mixtures provision which is not explicitly contained in the Walsh-Healey standard.

The Walsh-Healey standard, section 50-204.50, provides:

Exposures by inhalation, ingestion, skin absorption, or contact to any material or substance (i) at a concentration above those specified in the 'Threshold Limit Values of Airborne Contaminants for 1968' of the American Conference of Government Industrial Hygienists . . . shall be avoided.

The booklet, "Threshold Limit Values of Airborne Contaminants for 1968," contains several appendices, one of which contains a mixtures provision similar to the one contained in the OSHA standard. Essentially, Senco argues that when the Walsh-Healey standard and the original May 1971 OSHA standard referred to the ACGIH pamphlet, they incorporated only the body, and not the appendices of the pamphlet.

However, we conclude that the Walsh-Healey standard incorporated the mixtures provision. The Walsh-Healey standard incorporated "concentration[s] above those specified in [*10] the 'Threshold Limit Values of Airborne Contaminants for 1968." Accordingly, the Walsh-Healey standard incorporated any limits on airborne concentrations appearing anywhere in the ACGIH document. Logically, reference to the "concentrations" in the pamphlet would include the computation methods set forth in the appendix, including the mixtures provision that describes the method of calculating TLVs when confronted with the common problem of exposures to multiple air contaminants. In fact, the ACGIH Committee in the preamble to the 1968 ACGIH document refers to the mixtures provision as a method for "developing threshould limit values for mixtures." The ACGIH formula is commonly used to calculate the limits for mixtures, and the TLVs make little or no sense when applied to many real life industrial situations without the proper methods to calculate the TLVs of mixtures. 3 F.Patty, Industrial Hygiene and Toxicology, 235-6. Finally, throughout the introductory notes of the ACGIH pamphlet general reference is made to the appendices. This indicates that the appendices are an integral part of the pamphlet.

Assuming that the mixtures provision has been incorporated, Senco still [*11] contends that the standard is invalid because the language of the present standard's mixtures provision is mandatory while the mixtures provision in the source standard is merely advisory.

The Commission has found, in some instances, that changing advisory language to mandatory language is a substantive change. See Kennecott Copper Corp., 76 OSAHRC 81/A2, 4 BNA OSHC 1400, 1976-77 CCH OSHD P20,860 (No. 5958, 1976), aff'd, 577 F.2d 1113 (10th Cir. 1977). However, Senco's argument incorrectly assumes that the source of the OSHA standard is the ACGIH pamphlet. The source of the OSHA standard is the Walsh-Healey standard and both of these standards are mandatory. The Walsh-Healey standard states, "Exposures . . . to any material or substance . . . at a concentration above those specified in [the ACGIH document] . . . shall be avoided. . . ." (Emphasis added.) As the Fifth Circuit in Deering Milliken v. Marshall, 630 F.2d 1094 (5th Cir. 1980), observed:

Whether the Threshold Limit Values mandated by Walsh-Healey were only advisory when originally established by the American Conference of Governmental Industrial Hygienists . . . is irrelevant; Walsh-Healey incorporated [*12] those values as mandatory exposure limits, and maintenance of their mandatory character through promulgation of section 1910.1000 was not a modification of the pre-existing Walsh-Healey standard.

630 F.2d at 1102.

The analysis that the court used in Deering Milliken v. Marshall, supra, applies to this case. The Walsh-Healey standard incorporated any concentrations included in the appendices of the pamphlet by reference. Just as the Walsh-Healey standard transformed the advisory TLVs to mandatory TLVs, the Walsh-Healey standard transformed the advisory ACGIH mixtures formula to a mandatory one. When the OSHA standard was promulgated with a mandatory mixtures formula, this was not a change from its Walsh-Healey source standard.

IV

The final question in this case is whether the OSHA standard is invalid because it does not include the explicit exception for nonadditive substances found in the mixtures formula which was part of the Walsh-Healey standard. See note 4 supra.

For a period of two years following the effective date of the Act, the Secretary was authorized to summarily adopt established federal standards and national consensus standards as occupational [*13] safety and health standards. Section 6(a), 29 U.S.C. 655(a). Any substantive modification of a source standard requires the use of the rulemaking procedures set forth in section 6(b). The original Walsh-Healey standard, by adopting the ACGIH and its appendices, allowed for exceptions from the general rule that substances are additive when "there is good reason to believe that the chief effects of the different substances are not in fact additive." Therefore, section 1910.1000(d)(2)(i), adopted under section 6(a), is unenforceable to the extent it modified the substantive requirements of its source standard by imposing on an employer a duty to treat all toxic substances as additive. See Diebold, Inc. v. Marshall, 586 F.2d 1327, 1332 & n.6 (6th Cir. 1978).

However, we are unable to determine on the record in this case whether Senco's substantive duties are in any way affected by the Secretary's deletion of the exception for nonadditive mixtures. See Market Street Railway Co. v. Railroad Comm., 324 U.S. 548, 562 (1945), cited in Daniel Int'l Corp. v. OSHRC, 656 F.2d 925, 930 & n.9 (4th Cir. 1981). Nothing in the record indicates whether methyl ethyl ketone, [*14] xylene and acetone are in fact additive or not additive. If the cited substances are nonadditive, the cited subsection may not validly be applied. However, if Senco's compliance responsibilities are not altered, the standard may be validly applied. Senco cannot profit from the Secretary's failure to adopt an exception to a standar's requirements when it could not claim benefit of the exception even if adopted.

Accordingly, the judge's order granting Senco's motion to dismiss is set aside. The case is remanded to the chief judge n7 for further proceedings consistent with this opinion.

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n7 Judge Taylor is no longer with the Commission.

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DISSENTBY: ROWLAND

DISSENT:

ROWLAND, Chairman, dissenting:

I dissent from the majority's decision to remand this matter for further proceedings. In my view, the Walsh-Healey standard at 41 C.F.R. 50-204.50, on which the OSHA standard now published at 29 C.F.R. 1910.1000 is based, cannot reasonably be construed to include the mixtures provision appearing in the appendix to the ACGIH publication. [*15] Even assuming the Walsh-Healey standard can be so interpreted, the Secretary impermissibly changed the substance of the ACGIH mixtures provision by deleting language regarding non-additive substances when he promulgated the OSHA standard at issue in this case. Finally, the majority errs in concluding that despite the Secretary's deletion of that language, the standard is still enforceable as to substances which are additive, since that conclusion in effect rewrites the Secretary's standard.

As the majority notes, the Walsh-Healey standard prohibited exposure to "any material or substance" at a concentration in excess of that specified in the ACGIH publication. 41 C.F.R. 50-204.50 (emphasis added). That standard, however, also prohibits exposures to concentration above those set forth in two specifically designated tables, Table I and Table II. n1 The latter table is essentially the same as a listing entitled "Mineral Dusts" which appears in the ACGIH document and lists concerntrations for certain silica compounds, graphite, and nuisance particulates. n2

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n1 The full text of 41 C.F.R. 50-204.50(a)(1) as follows:

Exposures by inhalation, ingestion, skin absorption, or contact to any material or substance (i) at concentration above those specified in the "Threshold Limit Values of Airborne Contaminants for 1968" of the American Conference of Governmental Industrial Hygienists, except for the ANSI Standards listed in Table I of this section and except for the values of mineral dusts listed in Table II of this section, and (ii) concentrations above those specified in Tables I and II of this section, shall be avoided, or protective equipment shall be provided and used.

n2 Table I has no counterpart in the ACGIH document.

[*16]

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As the majority opinion indicates, the mixtures provision as it appears in the ACGIH publication applies only to worksites having at least two toxic air contaminants and requires that the employer consider the cumulative rather than individual effect of those substances. That is, the mixtures provision is a special provision under which a hazard may exist even if the concentration of each substance involved does not exceed the level prescribed for that substance by the ACGIH. The Walsh-Healey standard, however, gives no indication that it is intended to include such situations. Rather, it expressly refers the employer only to the concentrations specified by the ACGIH. In my view, the reasonable employer who reads this language together with the standard's references to the concentrations for individual substances as enumerated in certain tables would conclude that the purpose of the standard is to protect employees from exposure to such substances at levels above those expressly prescribed in the ACGIH booklet. Furthermore, the standard states that the employer is required to prevent exposure to [*17] "any" material or substance above the concentration specified. In view of the absence of any mention of mixtures of more than one substance or of the posssible cumulative effect of mixtures, an employer could not reasonably be said to understand that his duty extends to detecting and eliminating hazardous exposures to combinations of toxic substances when no substance individually exceeds the concentration prescribed by the ACGIH for that substance. As I have previously stated, standards cannot be construed to mean what the drafters might have intended but did not adequately express. Rather, employers must have fair notice of the obligations imposed by such standards. E.g., Bethlehem Steel Corp., 82 OSAHRC 19/C8, 10 BNA OSHC 1470, 1474, 1982 CCH OSHD P25,982 at 32,594 (No. 79-310, 1982) (concurring opinion).

The conclusion that the Walsh-Healey standard does not include the mixtures provision of the ACGIH publication is supported rather than weakened by the preamble to that publication on which the majority relies. Considering that the cumulative effects of mixtures of air contaminants may well have a significant effect on the health of employees, the ACGIH was [*18] aware that strict application of the threshold limit values prescribed for individual substances would not necessarily protect employees, and it so specifically stated. n3 Therefore, the Secretary was on notice that the ACGIH did not consider the concentrations othwerwise specified to be adequate in the case of mixtures of more than one substance. The Secretary clearly had the opportunity to provide in the Walsh-Healey standard for the specific circumstances presented by mixtures of air contaminants as did the ACGIH, but failed to do so.

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n3 According the ACGIH preamble, "[s]pecial consideration should be given also to the application of [threshold limit] values in assessing the health hazards which may be associated with exposure to mixtures of two or more substances."

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Finally, the subsequent history of the air contaminant standard suggests that even the Secretary had doubts as to whether he had in fact adopted the mixtures provision under Walsh-Healey. As the majority observes, when the Secretary first promulgated [*19] an air contaminant standard under OSHA in May, 1971, he essentially used the language that appeared in the Walsh-Healey standard. Thus the original OSHA standard, like the Walsh-Healey standard, contained no references to mixtures of substances or to the cumulative effect of such mixtures. When the standard was repromulgated in its present form in August, 1971 its wording was extensively changed. The Secretary deleted any mention of the ACGIH publication and, for the first time, expressly included a mixtures provision. Since the Secretary largely abandoned the wording as it had appeared in the earlier OSHA standard and preceding Walsh-Healey standard, and since the changes were ostensibly to improve the "accuracy" of the OSHA standard, one could reasonably conclude that the Secretary's intention was to conform his standard more closely to the provisions of the ACGIH document. Accordingly, it would appear that the Secretary's adoption at this time of a mixtures provisions is an implicit recognition that when he had first sought to implement the ACGIH document in the Walsh-Healey standard he had not included the mixtures provision appearing therein. As the majority observes, the [*20] Secretary is not permitted under 29 U.S.C. 655(a) to modify the substantive requirements of OSHA source standards.

In any event, regardless whether the mixtures provision of the ACGIH publication may properly be considered to have been incorporated in the original Walsh-Healey standard, the Secretary's subsequent OSHA standard at issue in this case is invalid because it deletes language regarding the application of the mixtures provision to combinations of substances which do not have cumulative or additive effect. The deletion constitutes an impermissible substantive change in the language of the Secretary's source standard. n4

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n4 In view of my conclusion that the standard is invalid for this reason, I need not consider as does the majority whether the standard is also invalid for the reason that the mixtures provision as it appeared in the ACGIH publication was only advisory rather than mandatory.

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As indicated above, the purpose of the mixtures provision as set forth in the ACGIH publication is to account for [*21] those situations in which, due to the additive or cumulative effect of several substances, strict application of the threshold limit values prescribed individually for those substances would not be adequate to protect employees. Accordingly, the ACGIH publication expressly provides that the mixtures formula is not to be applied to combinations of substances which do not in fact have an additive or cumulative effect. As the majority itself correctly concludes, the Secretary acted improperly in modifying his source standard so as to make the mixtures provision applicable to non-additive as well as additive situations.

The majority errs, however, in holding that the standard is nevertheless valid if the combination of substances involved in this case has an additive effect and in remanding for litigation of that question. The standard as adopted by the Secretary n5 draws no distinction between additive and non-additive situations. Rather, it mandates application of the mixtures formula in all cases where different air contaminants exist in combination. The majority's action, therefore, requires that the parties litigate a matter which is not an element of the cited standard and [*22] to which that standard is not directed. n6 By so doing, the majority rewrites the Secretary's standard. The effect of their result in this case is to insert into the Secretary's standard a limitation on the use of the mixtures formula which the Secretary himself deleted from the ACGIH publication when he promulgated the OSHA standard at issue here. Such action, for the purpose of saving the Secretary's standard from invalidity, is clearly contrary to the Commission's function under the Act as an impartial adjudicator. The Commission does not have regulatory authority and is not empowered to write into standards provisions which the Secretary did not adopt. See Mobil Oil Corp., 82 OSAHRC    , 10 BNA OSHC 1905, 1931-32, 1982 CCH OSHD P26,187 at 33,044-45 (No. 77-4386, 1982) (dissenting opinion); Shenango Co., 82 OSAHRC    , 10 BNA OSHC 1613, 1982 CCH OSHD P26,051 (No. 78-4723, 1982) (dissenting opinion).

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n5 See note 1 of the lead opinion.

n6 The majority's reliance on Market Street Ry. v. Railroad Comm'n, 324 U.S. 548 (1945) is misplaced. As the court noted in Daniel Int'l Corp. v. OSHRC, 656 F.2d 925, 930 n.9 (4th Cir. 1981), that case concerned issues of procedural due process which did not substantially affect the rights of the parties. As I have explained above, in the case now before us the Secretary's deletion of language which had appeared in the ACGIH publication resulted in a substantial alteration of the employer's duty. As the court in Daniel itself recognized, substantive modifications in the requirements of source standards adopted as OSHA standards under 29 U.S.C. 655(a) are inherently prejudicial because they effectively deny employers the right to comment on the standards. Id. at 930 & n.10.

[*23]

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Since the Walsh-Healey source standard did not incorporate the ACGIH mixtures provision and since in any event the OSHA standard substantively modified the terms of the ACGIH provision, I would vacate the citation in this case.