“SECRETARY OF LABOR,Complainant,v.GENERAL MOTORS CORPORATION,ROCHESTER PRODUCTS DIVISION,Respondent.UNITED AUTOMOBILE, AEROSPACE &AGRICULTURAL IMPLEMENT WORKERSOF AMERICA, LOCAL 1097,Authorized EmployeeRepresentative.OSHRC Docket No. 80-5439_DECISION_Before: BUCKLEY, Chairman, and CLEARY, Commissioner.BY THE COMMISSION:This case is before the Occupational Safety and Health Review Commissionunder 29 U.S.C. ? 661(i), section 12(j) of the Occupational Safety andHealth Act of 1970, 29 U.S.C. ?? 651-678 (\”the Act\”). The Commission isan adjudicatory agency, independent of the Department of Labor and theOccupational Safety and Health Administration (\”OSHA\”). It wasestablished to resolve disputes arising out of enforcement actionsbrought by the Secretary of Labor under the Act and has no regulatoryfunctions. _See_ section 10(c) of the Act, 29 U.S.C. ? 659(c).A citation issued by OSHA alleged that General Motors Corporation (\”GM\”)violated an employee instruction standard and two trenching standards. At issue is whether Administrative Law Judge Foster Furcolo erred invacating the two trenching items and affirming the employee instructionitem. For the reasons set forth below, we conclude that GM violated oneof the trenching standards, but we are divided as to whether the otheralleged violations were proven.[[1]]_Item 2: Unshored Trench_Item 2 of the citation alleged that GM violated 29 C.F.R. ? 1926.652(c)by failing to slope or shore the sides of a trench dug in \”hard orcompact soil.\”[[2]] At the time of the alleged violation, a crew ofsecond-shift employees was preparing for the installation of a trough tocollect oil from machinery in a large manufacturing building. Using thecompany’s construction equipment, employees had broken through part ofthe concrete floor and dug an L-shaped trench. The leg of the trenchrunning from north to south was about 20 feet long, 7 feet wide, and 10to 12 feet deep, with a pipe and adjacent ladder at its north end. Theleg of the trench running from east to west was 38 feet long, 7 feetwide, and 8 to 10 feet deep. At the western end of the east-west leg,the soil sloped from the bottom of the trench to the floor level, and aladder was located along the slope.GM planned to shore the trench before installing the trough. Long steelrods called \”channels\” were lowered with ropes into the trench andplaced against the walls every two feet. After the channels werepounded into the bottom of the trench by the bucket of the backhoe,employees at the top edge of the trench slid plywood sheets down behindthe channels. Employees in the trench then nailed the sheets together. Millwrights at the top edge then tied back the channels and fastenedthem to the concrete floor with brackets.On the evening at issue, employees were shoring the north-south leg, andboth walls of the north end of that leg had been shored. The east-westleg was still completely unshored. Jesse DeVittorio and Al LoMonaco,two of GM’s carpenter-masons, were in the trench nailing the plywoodsheets together. LoMonaco told DeVittorio that it was time for a coffeebreak, and they proceeded to leave the trench by the same route thatthey had entered it-the slope at the far end of the east-west leg–so asnot to bother a pipe fitter and a welder who were working next to theladder in the shored north end of the north-south leg. DeVittoriofollowed LoMonaco around the corner to the east-west leg. By the timeLoMonaco had climbed up the slope, the unshored north wall of theeast-west leg near the corner had collapsed on DeVittorio.Following the accident, the worksite was inspected by an OSHA complianceofficer. The compliance officer did not take any soil samples orperform any test to analyze the soil. However, he and other witnessesfor the Secretary testified that the material in which the trench hadbeen dug was backfill composed of sand, gravel, and loose rocks. Theytestified that the backfill was more firm in some walls than in others. Richard Carpenter, GM’s superintendent of plant engineering, testifiedthat the soil was \”backfill material\” that was \”sandy clay.\”Judge Furcolo concluded that the Secretary failed to prove a violationof section 1926.652(c). He determined that \”[t]he soil was certainlynot the ‘hard or compact’ type alleged in the citation . . . . \” Hestated that amending the citation and complaint to allege a violation ofsection 1926.652(b)[[3]] was not justified by the evidence, which \”doesnot establish that the soil was ‘unstable’ or ‘soft’ or any otherclassification.\” He held that because the soil had not been analyzedthere was insufficient proof of a violation of any trenching standard. The judge stated that another reason for vacating the citation item wasthat GM \”was doing the shoring in timely fashion.\” The judge noted thatGM did not use the trench in its unshored condition or \”refuse torecognize\” that it was required to shore the trench.The Secretary argues on review that he made the requisite showing thatsection 1926.652(c) applies to GM’s trench. He contends that the recordshows that the soil was at best hard and compact, and that such ashowing is sufficient to establish the applicability of the standard. The Secretary further asserts that GM violated the standard in that itallowed its employees to be exposed to unshored areas of the trench andto work in the partially shored north end of the trench. GM argues onreview that Judge Furcolo’s conclusion that section 1926.652(c) was notviolated and his reasons therefor should be affirmed.We hold that the judge did err in vacating this item because it was notproved whether the soil was governed by section 1926.652(b) or bysection 1926.652(c). The trenching standards divide earth materialsinto categories, with trenches dug in each category requiring adifferent degree of protection. The greatest degree of protection byway of sloping or shoring is required for \”unstable or soft\” soil. Trenches dug in such soil are governed by section 1926.652(b). At theother extreme, trenches in \”Solid Rock, Shale or Cemented Sand andGravels\” need not be sloped or shored at all. _See_ Table P-1, appendedto section 1926.652. Between these types are trenches dug in \”hard orcompact\” soil, which are governed by section 1926.652(c). Suchtrenches, if more than five feet deep, must be sloped above thefive-foot level or shored. _E.g_., _CCI, Inc_., 80 OSAHRC 127\/D4, 9 BNAOSHC 1169, 1981 CCH OSHD ? 25,091 (No. 76-1228, 1980), _aff’d_, 688 F.2d88 (10th Cir. 1982). Although the shoring requirements for trenches dugin hard, compact soil are less demanding than for trenches dug in soft,sandy, or filled soil, both sections require unsloped trenches to beshored. _See_ Table P-2, appended to section 1926.652. It is not thesubject of dispute that the trench in this case was substantially morethan five feet deep and that most of its walls were not sloped. It isclear from the record that GM knew that it was required to shore orslope the walls of the trench and that it had elected to shore thetrench walls due to the worksite conditions.GM’s argument that the Secretary failed to prove the applicability ofsection 1926.652(c) therefore reduces to the argument that it shouldhave been cited under the more stringent provision of section1926.652(b) instead. However, under the circumstances of this case,there is no difference in the requirement of the two standards: bothrequire that the trench walls be shored. As the Secretary points out,he gave GM the benefit of the doubt by citing under subsection (c)rather than subsection (b) because subsection (c) requires lessprotection. Thus, if there was a defect in the citation, it tended tobenefit GM and does not constitute grounds to vacate the citation. Weconclude therefore that the judge erred in vacating the citation forthat reason.GM also argues that, even if the standard applies, it was not inviolation because the employees in the trench were there for the purposeof installing the shoring required to comply with the standard. Thecompany contends that a violation of the standard only occurs if thereis \”needless exposure\” of employees to the unshored trench walls.We agree with GM’s argument that an employer cannot be found inviolation of the standard based merely on the presence in the trench ofemployees installing the shoring required by the standard. As GMcorrectly states, the question is whether employee presence in thetrench is needless. In this case, four employees were in thenorth-south leg immediately before the accident. A pipe fitter and awelder were working in the shored portion at the north end of the leg. The other two employees were nailing together the plywood sheets thatformed part of the shoring system. Inasmuch as the employees in thenorth-south leg were either working in a part of the trench that hadalready been shored or were engaged in installing the shoring in thatleg, GM did not violate the standard in the north-south leg.The east-west leg, however, was completely unshored, and GM did not takeany steps to keep the employees out of that leg. Moreover, at the westend of that leg was a dirt slope along which ran a ladder that employeesused to enter and leave the trench. The presence of the slope and laddermade it reasonably predictable that employees would use the east-westleg to gain access to their work area in the north-south leg, and indoing so they would be exposed to the unshored walls of the east-westleg. Because GM did not limit employee access to the trench so as toeliminate the unnecessary exposure of employees to the unshored walls,GM did violate the standard with respect to the east-west leg. _FloydS. Pike Electrical Contractor, Inc_., 77 OSAHRC 26\/B11, 5 BNA OSHC 1088,1977-78 CCH OSHD ? 21,584 (No. 12398, 1977), _aff’d_, 576 F.2d 72 (5thCir. 1978).We reject GM’s argument that the citation should be vacated because theaccident resulted from employee disobedience to instructions to remainout of the unshored parts of the trench. The proper inquiry is not thecause of the accident, but whether GM violated the standard as alleged. _See_ _Champlin Petroleum Co. v. OSHRC_, 593 F.2d 637, 642 (5th Cir.1979) (Act is designed to achieve abatement of hazardous conditions, notfix blame for particular injury). The finding of a violation is notbased on the occurrence of the accident but on the foreseeable exposureof GM’s employees to the unshored east-west leg of the trench. [[4]]The Commission therefore affirms the citation item alleging a violationof section 1926.652(c). The parties stipulated that DeVittorio’sinjuries were \”serious\” within the meaning of section 17(k) of the Act,29 U.S.C. ? 666(i). Based on that stipulation and on the obviousdanger presented by the unprotected walls of a trench 8 to 10 feet deep,the Commission finds a substantial probability that death or seriousharm could have resulted from the violation. We therefore conclude thatthe violation was \”serious.\” Having considered the penalty criteria setforth in section 17(j) of the Act, 29 U.S.C. ? 666(i), we assess apenalty of $50 for the serious violation of section 1926.652(c)._Item 3: Additional Precautions_Item 3 of the citation alleges that GM violated section 1926.652(e),which requires additional precautions in trenches adjacent to backfilledexcavations or subject to vibrations from the operation ofmachinery.[[5]] Witnesses for both parties testified that the area inwhich the trench was dug consisted of backfill.There was also some testimony at the hearing that the trench wassubjected to vibrations. Two of GM’s employees–John Boushie, asecond-shift pipe fitter, and Anthony Davide, a first-shiftmillwright–testified that both the backhoe, which was located near theedge of the trench on a concrete slab, and another piece of equipmentcalled the \”in-line transfer machine,\” which was situated about 10 to 12feet away from the trench, vibrated when they were in operation. Theemployees did not say, however, how much the machines vibrated. JamesConlon, the Secretary’s expert witness, testified that when the backhoepounded the steel channels it transmitted vibrations into the soil thatcould extend for 5 feet from the channel. The backhoe had been drivingchannels just before the accident. When asked if there would bevibrations in the soil when the in-line transfer machine was inoperation, Conlon testified that it was possible. He stated, however,that \”[v]ibrations are difficult to predict,\” and he could not be surewhether the in- line transfer machine produced vibrations in the soilbecause he had not been at the worksite. Conlon further acknowledgedthat any opinion as to vibrations without having felt them is \”highlytheoretical\” and \”into the realm of speculation.\”The compliance officer testified that he did not measure nor did he knowhow much the machines vibrated. According to Carpenter, GM’ssuperintendent of plant engineering, the in-line transfer machine wasdesigned not to vibrate, and, even if it did, the vibrations would benegligible. He also testified that any vibrations from the in-linetransfer machine or the backhoe had \”no bearing\” on the collapse of thewalls of the east-west leg, for the vibrations were \”in the manner ofthousandths of an inch.\”Judge Furcolo vacated this item. Although he found that the soil in thearea was backfill,[[6]] he went on to conclude that a violation of thestandard was not proven because the Secretary did not establish that thetrench was \”subjected to vibrations from . . . the operation ofmachinery.\” Judge Furcolo determined that the word \”vibrations\” means\”vibrations sufficient to have some effect that might contribute to aslide or cave-in of any nearby excavation or trench.\” After reviewingthe testimony and noting the lack of evidence as to the degree of thevibration, he concluded that, even considering the evidence mostfavorable to the Secretary, there was no proof that the trench wassubjected to the alleged vibrations. He therefore vacated the citationitem.The Secretary argues on review that the judge misinterpreted section1926.652(e). He contends that the word \”or\” in the standard signifiesthat it applies in two distinct situations: where a trench is adjacentto backfilled soil, or where the trench is subjected to vibrations fromthe operation of machinery. According to the Secretary, he met hisburden of proof under the standard by establishing that the unshoredtrench was dug in backfill, regardless of whether the trench was alsosubject to vibrations. The Secretary also argues that, in any event,the trench was subjected to vibrations from the operation of machinery. GM contends on review that it was in the process of shoring the trench,and the Secretary failed to show what additional precautions were required.Chairman Buckley would affirm the judge’s disposition, although he woulddo so for reasons different than those stated by the judge. He notesthat section 1926.652(e) requires shoring or bracing _in addition to_precautions taken to comply with sections 1926.652(b) or 1926.652(c). In this case, GM had already shored part of the trench and was in theprocess of shoring the remainder. There is no evidence that GM’sshoring either was or would be, when completed, insufficient to protectemployees in the trench. On the contrary, Conlon, the Secretary’s ownexpert, testified that the shoring GM had been installing would havebeen adequate when completed. The Secretary’s allegation is based onthe same conditions that allegedly constitute a violation of section1926.652(c):the absence of any protection at all for portions of the trench walls. To establish a violation of section 1926.652(e), the Secretary wouldhave to prove that the shoring the employer was installing wasinadequate to protect against cave-ins from vibrating machinery or thepresence of backfill. The employer’s failure here to prevent exposureof employees to the hazard of a cave-in prior to completion of itsshoring does not establish that it also failed to take precautions inaddition to those required by section 1926.652(b) or (c). The Chairmantherefore concludes that the Secretary failed to prove that GM violatedsection 1926.652(e).Commissioner Cleary would affirm the citation item. He agrees with theSecretary’s argument that the plain language of section 1926.652(e)requires additional shoring or bracing under two alternativeconditions–where trenches are dug adjacent to backfilled areas _or_where trenches are subject to vibrations. _Cedar Construction Co_., 77OSAHRC 63\/A2, 5 BNA OSHC 1311, 1977-78 CCH OSHD ? 21,772 (No. 10929,1977), _aff’d_ 587 F.2d 1303 (D.C. Cir. 1978). He also finds itirrelevant that the required additional precautions would have beentaken some time in the future. Just as GM violated section 1926.652(c)because the required shoring was not in place when employees wereunnecessarily in unshored parts of the trench, GM violated section1926.652(e) because the trench was dug in backfill and lacked additionalprecautions. An employer’s failure to take _any_ precautions to protectemployees against the walls of a trench collapsing violates theemployer’s duty to take the additional precautions required by section1926.652(e) as well as the precautions required by section 1926.652(c). Although the requirements of sections 1926.652(c) and 1926.652(e) areclosely related, an employer is not unfairly burdened when the same orsimilar conditions are the subject of more than one citation item, for asingle action on the employer’s part may be all that is necessary toachieve compliance with the cited standards. _H.H. Hall ConstructionCo_., 81 OSAHRC 91\/D12 10 BNA OSHC 1042, 1981 CCH OSHD ? 25,712 (No.76-4765, 1981). Moreover, to the extent that the same or similarconduct may violate more than one standard, the Commission has thediscretion to assess a single, combined penalty for the violations. _Wright & Lopez, Inc_., 81 OSAHRC 92\/D10, 10 BNA OSHC 1108 ,1981 CCHOSHD ? 25,728 (No. 76-256, 1981); _H.H. Hall_, 10 BNA OSHC at 1049, 1981CCH OSHD at p. 32,059. Because the violation of section 1926.652(e)involves conduct similar to that of section 1926.652(c), CommissionerCleary would assess a combined penalty for the violations of sections1926.652(c) and (e).Under section 12(f) of the Act, 29 U.S.C. ? 661(e), official action canbe taken by the Commission with the affirmative vote of two members. The two Commission members disagree whether the judge erred in hisdisposition of this citation item. To resolve this impasse and topermit this case to proceed to a final resolution, the members haveagreed to affirm the judge’s decision vacating this item but accord itthe precedential value of an unreviewed judge’s decision. _See_ _LifeScience Products Co_., 77 OSAHRC 200\/A2, 6 BNA OSHC 1053, 1977-78 CCHOSHD ? 22,313 (No. 14910, 1977), _aff’d sub nom. Moore v. OSHRC_, 591F.2d 991 (4th Cir. 1979)._Item 1: Instruction of Employees_Item 1 of the citation alleged that GM violated section 1926.21(b)(2),which requires employers to instruct employees in the recognition andavoidance of unsafe conditions.[[7]] Judge Furcolo affirmed the item. He stated that the standard requires an employer to issue instructionsregardless of the knowledge or experience of its employees. The judgefound that \”[t]he witnesses who testified in substance that there wereno instructions were positive and definite in their testimony to thateffect while those who indicated the contrary were comparatively vagueand indefinite.\” For that reason, he concluded that GM did not give itsemployees instructions on trenching hazards and therefore failed tocomply with the standard. Judge Furcolo determined that the violationwas serious. He assessed a penalty of only $50 because \”it was notunreasonable for [GM] to believe its employees were familiar withtrenching hazards…\”The Commissioners disagree on the disposition of this item. Commissioner Cleary would adopt the judge’s decision and affirm thecitation item. He notes that employees Boushie, LoMonaco, Davide, andThomas Martin, a second-shift welder, testified that no GM supervisortold them not to go into an unshored trench or gave them oral or writteninstructions about the specific safety hazards involved in working inand around trenches. Those four employees also testified that they hadnot attended any safety meetings at GM during which trenching or shoringhad been discussed. Boushie, Martin, and Davide stated that they werenever told by any supervisor about OSHA’s trenching standards. Boushie,Martin, and LoMonaco testified that no supervisor, including their groupleader, instructed them to stay out of the east-west leg of the trench. Boushie testified that this was the first trench that he had worked inat GM. Martin stated that when he began work at GM in 1973 he was notgiven any safety booklets. When he was shown a booklet entitled \”SafetyProcedures and Instructions, Rochester Products\” at the hearing, hedeclared that he had never seen it before.Gary Murphy, GM’s supervisor for the second shift, and Nick Bianchi, thecrew’s \”group leader\” who directed the work, testified that there wereno formal safety meetings at GM regarding trenching hazards. Rather,informal discussions were held at which employees told their ideas aboutimproving working conditions. Murphy testified that he specificallyinstructed Bianchi, LoMonaco, and DeVittorio to remain out of theunprotected areas of the trench, and he never observed employees in suchareas when he visited the trench.In _C. Kaufman, Inc._, 78 OSAHRC 3\/C1, 6 BNA OSHC 1295, 1297, 1977-78CCH OSHD ? 22,481, p. 27,099 (No. 14249, 1978), the Commission statedthat it will usually accept an administrative law judge’s evaluation ofwitnesses’ credibility because the judge was the one who \”lived with thecase, heard the witnesses, and observed their demeanor.\” In this case,the judge based his finding that GM had not instructed employees inhazards associated with trenches on his conclusion that the employee whotestified that no such instructions were given were more credible thanGM’s supervisors, whose testimony he stated was vague and indefinite.Commissioner Cleary accepts Judge Furcolo’s credibility determinationand finds that GM did not instruct its employees regarding trenchinghazards.Moreover, even crediting the testimony of GM’s supervisors, what littleaction GM took to instruct its employees about trench hazards wasinsufficient under the standard. GM distributed its safety booklet tosome employees, but at least one employee, Martin, had never seen itbefore the hearing in this case. In any event, the booklet contained noinstructions on hazards involved in construction work in general, andtrenches in particular. The standard is not satisfied by instructionsthat fail to deal entirely with major hazards that employees face. _See_ _National Industrial Constructors, Inc. v. OSHRC_, 583 F.2d 1048(8th Cir. 1978) (section 1926.21(b)(2) requires more than a generalsafety program). Whatever safety meetings were held were informal andunstructured. Even if the testimony of Murphy that he gave on-the-jobwarnings to remain out of the unshored areas of the trench was to becredited, such warnings alone do not satisfy the cited standard. _Sawnee Electric Membership Corp_., 77 OSAHRC 24\/C10, 5 BNA OSHC 1059,1061, 1977-78 CCH OSHD ? 21,560, p. 25,873 (No. 10277, 1977)(Cleary,Commissioner, dissenting). Moreover, GM’s failure to give theinstructions required by the standard cannot be excused on the basisthat the employees were experienced. _See_ _Getty Oil Co. v. OSHRC_, 530F.2d 1143 (5th Cir. 1976). All employees, both experienced andinexperienced, are entitled to the Act’s protection.Chairman Buckley would vacate the citation item. The standard requiresthat employers instruct employees, but it does not specify the natureand extent of the required instructions. A violation of such a standardcannot be predicated upon a finding that an employer’s safety programcould have been improved. Rather, there must be a showing that theemployer breached a duty to give reasonable instructions. _H.C. NuttingCo. v. OSHRC_, 8 BNA OSHC 1241, 1242, 1980 CCH OSHD ? 24,548, p. 30,030(6th Cir. 1980); _Dravo Engineers and Constructors_, 84 OSAHRC __\/_, 11BNA OSHC 2010, 2011-12, 1984 CCH OSHD ? 26,930, p. 34,507 (No. 81-748,1984). In determining whether the instructions that an employer gavewere reasonable, the substance of the employer’s safety program is moreimportant than its form. _Jones & Laughlin Steel Corp_., 82 OSAHRC34\/A2, 10 BNA OSHC 1778, 1782, 1982 CCH OSHD ? 26,128, p. 32,887 (No.76-2636, 1982); _Texland Drilling Corp_., 80 OSAHRC 106\/C13, 9 BNA OSHC1023, 1026, 1980 CCH OSHD ? 24,954, p. 30,788 (No. 76-5307, 1980). Thestandard should not be interpreted to require employers to tell theiremployees what is obvious. _Butler Lime and Cement Co. v. OSHRC_, 658F.2d 544 (7th Cir. 1981). Employers can permissibly rely on the judgmentof experienced employees to perform their work in a safe and propermanner. _See_ _Davey Tree Expert Co_., 84 OSAHRC 11\/D11, 11 BNA OSHC1898, 1900, 1983-84 CCH OSHD ? 26,852, p. 34,400 (No. 77-2350, 1984);_Jones & Laughlin Steel Corp_., 10 BNA OSHC at 1783, 1982 CCH OSHD at p.32,888. Thus, section 1926.21(b)(2) requires a level of instructionappropriate to the circumstances.In Chairman Buckley’s view, the record shows that GM did give adequateinstructions in light of the experience and knowledge of the employeesdoing the work. Judge Furcolo found that it was reasonable for GM tobelieve that its employees were familiar with trenching hazards, andthat finding is supported by the record. Gary Murphy, the supervisorfor the second shift, testified that the crew was composed of skilledtradesmen, not general laborers, who had shored many trenches and knewwhat they were doing. The testimony of the employees shows that theyknew the hazards presented by unshored trenches. Boushie acknowledgedthat he was aware of the hazards of unshored trenches because he hadprior experience on construction jobs. Davide admitted that while hehad been an apprentice at GM his leader had instructed him to stay outof unshored trenches. LoMonaco was asked if he knew not to go into anunshored portion of a trench, and replied that he never went down intosuch an area.The record also shows that GM had an ongoing safety program. Safetybooklets were distributed to employees when first hired. Theinstructions in those booklets were supplemented by oral on-the-jobinstructions and informal safety meetings. Both Murphy and Bianchitestified that trenching hazards had been addressed during informalsafety meetings. Murphy and Bianchi also stated that they hadinstructed employees to stay out of the unshored portions of the trenchinvolved in this case. Considering the experience of the employees andtheir awareness of the hazards associated with trenches, ChairmanBuckley concludes that the instructions GM gave its employees concerningsuch hazards were reasonable and met the general requirement of section1926.21(b)(2).As noted above, section 12(f) of the Act, 29. U.S.C. ? 661(e), statesthat official action can be taken by the Commission with the affirmativevotes of two members. To resolve their impasse on this issue and topermit this case to proceed to a final resolution, the members haveagreed to affirm the judge’s decision on this citation item but accordit the precedential value of an unreviewed judge’s decision.In sum, the Commission affirms citation item 2 and assesses a $50penalty for the serious violation of section 1926.652(c). The membershave also agreed to affirm Judge Furcolo’s disposition of citation items1 and 3, alleging violations of sections 1926.21(b)(2) and 1926.652(e),but accord their decision on those two items no precedential value.FOR THE COMMISSIONRAY H. DARLING, JR.EXECUTIVE SECRETARYDATED: APR 26 1985————————————————————————FOOTNOTES:[[1]] As established by the Act, the Commission is composed of threemembers. Section 12(a), 29 U.S.C. ? 661(a). Currently, the Commissionhas two members as a result of a vacancy.[[2]] Section 1926.652(c) states:Sides of trenches in hard or compact soil, including embankments, shallbe shored or otherwise supported when the trench is more than 5 feet indepth and 8 feet or more in length. In lieu of shoring, the sides ofthe trench above the 5-foot level may be sloped to preclude collapse,but shall not be steeper than a 1-foot rise to each 1\/2-foot horizontal….[[3]] The standard provides:Sides of trenches in unstable or soft material, 5 feet or more in depth,shall be shored, sheeted, braced, sloped, or otherwise supported bymeans of sufficient strength to protect the employees working withinthem. See Tables P-1, P-2 (following paragraph (g) of this section).Appended to section 1926.652, and referred to by it, is Table P-1, whichprovides that trenches dug in solid rock, shale, or cemented sand andgravels need not be sloped.[[4]] The parties also dispute whether there was needless employeeexposure to ground collapse during the process of shoring. The partiesput on conflicting evidence as to whether workmen stood in thenorth-south leg of the trench to guide steel channels being pounded intothe trench floor by the backhoe. If employees did enter the unshoredleg for that purpose, that would constitute another basis for aviolation of this standard because GM conceded that this work could havebeen accomplished without employees in the trench. Inasmuch as employeeuse of the east-west leg for exiting clearly establishes a violation ofthe standard, we will not reach the close credibility questions raisedby this secondary dispute.[[5]] Section 1926.652(e) reads as follows:Additional precautions by way of shoring and bracing shall be taken toprevent slides or cave-ins when excavations or trenches are made inlocations adjacent to backfilled excavations, or where excavations aresubjected to vibrations from railroad or highway traffic, the operationof machinery, or any other source.[[6]] GM argues that Judge Furcolo erroneously found that the trench was\”adjacent to\” a backfilled area because it was within 10 to 30 feet ofsuch an area. Any such error was harmless. Statements earlier in thejudge’s decision to the effect that the area in which the trench was dugwas backfill are sufficient to establish that the trench was \”adjacentto\” backfill under section 1926.652(e). _J.D. Blum Construction Co_.,76 OSAHRC 58\/D14, 4 BNA OSHC 1255, 1976-77 CCH OSHD ? 20,735 (No. 3543,1976).[[7]] The standard provides:The employer shall instruct each employee in the recognition andavoidance of unsafe conditions and the regulations applicable to hiswork environment to control or eliminate any hazards or other exposureto illness or injury.”