SECRETARY OF LABOR, Complainant, v. MORRISON-KNUDSEN, INC., Respondent. OSHRC Docket No. 80-0345 _DECISION_ Before: BUCKLEY, Chairman; WALL, Commissioner. BY THE COMMISSION: This case is before the Occupational Safety and Health Review Commission under 29 U.S.C. § 661(j), 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 issue is whether Morrison-Knudsen, Inc., violated the OSHA standard at 29 C.F.R. § 1926.52(a) because certain employees were not wearing equipment to protect against excessive noise.[[1]] Administrative Law Judge Barbara Hassenfeld vacated the item, finding that the Secretary had not proven that Morrison-Knudsen's employees lacked protection from excessive noise for a longer period of time than the standard permits. We affirm her decision. During 1979, Morrison-Knuden was a contractor for the construction of the Seabrook Nuclear Power Plant in New Hampshire. The company was responsible for the construction of two tunnels under Hampton Bay. To dig the tunnels, material was excavated using a large tunneling machine, or "mole." Railroad tracks ran through the sections of tunnel that had already been dug. Railroad cars running on tracks transported workers and equipment to the area in which the mole was working; they also transported moled rock away from the digging area. On October 30, 1979, an OSHA compliance officer inspected the worksite. Using a sound level meter, he measured noise levels of 96 to 106 dBA on the railway in a tunnel. On December 13, he returned to the worksite to measure the amount of noise to which employees were exposed. On that date, personal noise dosimeters were worn by six Morrison-Knudsen employees during their work shifts. The compliance officer also took sound level meter measurements at various locations on the worksite. Because the dosimeter readings showed excessive noise exposures and the compliance officer observed certain employees not wearing hearing protective equipment, the Secretary issued a citation alleging that Morrison-Knudsen violated section 1926.52(a). Section 1926.52 provides in part: § 1926.52 _Occupational noise exposure._ (a) Protection against the effects of noise exposure shall be provided when the sound levels exceed those shown in Table D-2 of this section when measured on the A-scale of a standard sound level meter at slow response. (b) When employees are subjected to sound levels exceeding those listed in Table D-2 of this section, feasible administrative or engineering controls shall be utilized. If such controls fail to reduce sound levels within the levels of the table, personal protective equipment as required in Subpart E, shall be provided and used to reduce sound levels within the levels of the table. (c) If the variations in noise level involve maxima at intervals of 1 second or less, it is to be considered continuous. (d)(1) In all cases where the sound levels exceed the values shown herein, a continuing, effective hearing conservation program shall be administered. TABLE D-2 -- PERMISSIBLE NOISE EXPOSURES Duration per day, hours Sound level dBA slow response 8 ..........................................90 6 ..........................................92 4 ..........................................95 3 ..........................................97 2 ..........................................100 1 1/2 ....................................102 1........................................... 105 1/2........................................ 110 1/4 or less.............................. 115 (2)(i) When the daily noise exposure is composed of two or more periods of noise exposure of different levels, their combined effect should be considered, rather than the individual effect of each. Exposure to different levels for various periods of time shall be computed according to the formula set forth in paragraph (d)(2)(ii) of this section. (ii)Fe=(T_1 /L_1 )+(T_2 /L_2 )+...+(T_n /L_n )where: Fe=The equivalent noise exposure factor. T=The period of noise exposure at any essentially constant level. L=The duration of the permissible noise exposure at the constant level (from Table D-2). If the value of Fe exceeds unity (1) the exposure exceeds permissible levels. The personal noise dosimeters that the compliance officer used to measure noise exposures are devices that continually measure sound levels and automatically apply the cumulation formula in section 1926.52(d)(2)(ii). The dosimeter calculates Fe, the equivalent noise exposure factor, and expresses the result of its calculation in terms of the percentage of the permitted noise exposure. A dosimeter reading of more than 100% means that Fe is greater than one, which in turn means that the permissible daily noise exposure has been exceeded. _See_ _generally_ _New England Container Co_., 84 OSAHRC 55/A2, 12 BNA OSHC 1368, 1371 n.7, 1984-85 CCH OSHD ¶ 27,148, pp. 35,045-46 n.7 (No. 78-1539, 1984). All six dosimeters that the compliance officer attached to Morrison-Knudsen employees yielded readings exceeding 100% during the employees' work shifts. However, Morrison-Knudsen provided personal hearing protection equipment to its employees, and most of the employees who were observed by the compliance officer were wearing the equipment, including four of the employees whose noise exposure was measured with dosimeters. The Secretary does not argue that the equipment was not adequate to protect those employees. Thus, the Secretary's allegation reduces to whether Morrison-Knudsen violated the standard with respect to the two employees who were observed to be without hearing protection. Those two employees were John Shields and Sterling Grondin. Both were motormen who drove locomotives back and forth through the tunnels to the moling area. The compliance officer placed a dosimeter on Shields at 2:34 p.m., immediately before the start of his shift, and removed it at 10:40 p.m., at the end of the shift. The dosimeter read 346% at the end of the shift, indicating that Shields received about three and one-half times the permissible dose of noise. Around 5:30, the compliance officer rode on the locomotive that Shields was operating and measured the noise with a sound level meter. With the locomotive stationary, he measured a noise level of 97 dBA. With locomotive moving down the track, the noise level was 104 to 105 dBA. Around 9:30, the compliance officer observed that Shields was not wearing hearing protection.[[2]] He again observed Shields without hearing protection at the end of the shift, as Shields was preparing to leave the tunnel. The compliance officer attached a dosimeter to Grondin at 2:32 p.m. and removed it at 11:15 p.m. It read 217%, indicating that Grondin received over twice the permissible noise dose. The compliance officer observed that Grondin was not wearing hearing protection when he removed the dosimeter. The compliance officer asked Grondin whether he wore hearing protection and, according to the compliance officer, Grondin replied that he did not because he likes to be able to hear the machinery. We conclude that this evidence is insufficient to prove that Morrison-Knudsen violated the standard. We first note that the standard does not require that protective equipment always be worn when noise levels are between 90 and 115 dBA. Table D-2 lists permissible times of exposure for this range of noises levels. For example, an employee who works for eight hours in an area where the noise level is 95 dBA may work for four hours without hearing protection and still comply with the standard by wearing protective equipment the remainder of the time. The dosimeter readings for Shields and Grondin show their cumulative noise exposure throughout the day but do not show for how long they were exposed to any particular noise level. Thus, the dosimeter readings do not show the length of time that Shields and Grondin were required by the standard to wear protective equipment. They show only that if Shields and Grondin never wore protective equipment at all during the sampling period, a violation of the standard occurred. Although sound level readings were also taken, the Secretary introduced no evidence that any particular level continued for a particular period of time. It is therefore not possible on this record to say that Shields and Grondin were required to wear protective equipment for any particular period of time. The record must therefore show that they were not wearing protective equipment for the entire time they wore noise dosimeters. All the record shows as to Shields is that the compliance officer observed him without protective equipment for at most four minutes during Shields' shift and momentarily at the end of the shift, as Shields was preparing to leave the tunnel. The Secretary would have us infer from this that Shields never wore protective equipment during his shift. We decline to draw such an inference. Personal hearing protection equipment--earplugs or earmuffs--is easily put on and removed, and some people find the equipment uncomfortable when worn constantly. Thus, an employee may well choose to wear the equipment during only part of the day. In particular, the employee may wear the equipment when the noise level is high when the noise level is high, at which times the need for the equipment is most obvious, and remove the equipment when the noise level is relatively low. Such a procedure is permitted by the standard, which allows the employee to be unprotected for some time at all noise levels below 115 dBA and for a relatively large percentage of an eight-hour workday at the lower range of the noise levels listed in Table D-2 of the standard. Thus, where the employer makes protective equipment available for employees' use, evidence that an employee did not wear such equipment for a few minutes during the day does not suggest that the employee never wore the equipment during the entire day. The preponderance of the evidence therefore does not support a finding that Shields was exposed to excessive noise levels while unprotected by personal protective equipment. The compliance officer observed Grondin without hearing protection only momentarily, at the end of Grondin's shift. For the reasons just stated, this observation does not prove Grondin failed to wear hearing protection during the entire day. The only evidence tending to show that Grondin did not wear protection during his entire shift is the compliance officer's testimony that he asked Grondin whether he wore hearing protection and that Grondin replied he did not because he liked to be able to hear the machinery. Morrison-Knudsen argues that we should not rely on this evidence because it is hearsay. We put to one side whether this evidence should be technically classified as hearsay. See Fed. R. Evid. 801(d)(2)(D) (out-of-court declarations by employees concerning matter within scope or employment classified as non-hearsay rather than exception to hearsay rule). Whether evidence should be classified as non-hearsay for the purpose of determining its admissibility bears little relation to its value to support the Secretary's case. We therefore note that even if this testimony might be classified as non-hearsay for the purpose of determining its admissibility, its weight must be determined after its hearsay nature is taken into account. Grondin's statement is an out-of-court declaration offered to prove the truth of the matter it contains. Its weight depends on such factors as whether the question was put to Grondin conversationally and answered casually without recognition of its import, as well as on Grondin's propensity to tell the truth, the compliance officer's ability to correctly appreciate Grondin's words, and his relaying them accurately to the administrative law judge. A declaration that is introduced through another's testimony inherently has less probative value than the delcarant's own testimony. When an out-of-court statement is introduced, the trier of fact has no opportunity to assess the credibility of the person who made the statement and must therefore allow for the possibility that the statement is exaggerated, incomplete, taken out of context, or even false. Also, neither the other party nor the judge has an opportunity to cross-examine the person who made the statement. The only person able to evaluate the statement's credibility is the person who heard the statement and is testifying to its contents. These considerations suggest that out-of-court statements cannot always be taken at face value. On its face, Grondin's statement tends to show that he did not wear hearing protection during the entire time he wore the dosimeter. However, other possibilities also suggest themselves. Even if Grondin had worn hearing protection for much of his shift, he may have felt he had done something wrong when he was observed by the compliance officer without hearing protection; therefore he may have thought it necessary to offer an excuse for not wearing the protection. Or, it is possible that Grondin spoke facetiously to the compliance officer when he said he did not wear hearing protection because he "likes to be able to hear the machinery." The compliance officer's only personal observation of Grondin's not wearing hearing protectors came at the end of Grondin's shift, after Grondin would probably have removed the hearing protectors if he had been wearing them, and thus is of little corroborative value. We also note that Judge Hassenfeld, who was in a somewhat better position to judge than we are, was evidently unimpressed with the compliance officer's testimony concerning Grondin. On balance, we think the compliance officer's testimony leaves substantial uncertainty over whether Grondin never wore hearing protection. We also note that the Secretary could have presented stronger evidence on the point. He could have attempted to definitively establish that Grondin did not wear hearing protection through discovery, such as a request for admission.[[3]] If unable to establish the point through discovery, he could have produced Grondin to testify. The Secretary bears the burden of proving a violation by the preponderance of the evidence. Like Judge Hassenfeld, we are not persuaded that he carried that burden here.[[4]] We conclude that the Secretary did not present sufficient evidence to meet his burden of proving that Shields and Grondin did not wear hearing protection on the day of the alleged violation. Accordingly, item 1A of the citation is vacated.[[5]] FOR THE COMMISSION Ray H. Darling, Jr. Executive Secretary Dated: March 3, 1987 ------------------------------------------------------------------------ SECRETARY OF LABOR, Complainant v. MORRISON-KNUDSEN COMPANY, Respondent OSHRC NO. 80-0345 Appearances: For Complainant, Albert H. Ross, Regional Solicitor U.S. Department of Labor For Respondent, Robert D. Moran, Esq. Moran & Chaplin _STATEMENT OF PROCEEDINGS:_ On December 28, 1979, Respondent was issued a Serious citation and a proposed penalty of $700.00. Respondent contested both. Trial was held for seven days in Boston, Massachusetts. The relevant regulations are: 1A. 29 C.F.R. 1926.52(a): Protection against the effects of noise exposure shall be provided when the sound levels exceed those shown in Table D-2 of this section when measured on the A-scale of a standard sound level meter at slow response. The citation alleges "Seabrook Station Tunnels--Employees were not wearing hearing protection such as motor men, car pass operators and others in the work area of the mole." 1B. 29 C.F.R. 1926.52(b): When employees are subjected to sound levels exceeding those listed in Table D-2 of this section, feasible administrative or engineering controls shall be utilized. If such controls fail to reduce sound levels within the levels of the table, personal protective equipment as required in Subpart F, shall be provided and used to reduce sound levels within the levels of the table. The citation alleges "Seabrook Station Tunnels--Motormen, brake men, mole operator, rock drillers, car pass operator." 1C. 29 C.F.R. 1926.52(d)(1) In all cases where the sound levels exceed the values shown herein, a continuing, effective hearing conservation program shall be administered. This regulation was substituted for 29 C.F.R. 1910.95(b)(3) by action allowed August 18, 1980. The citation alleges "Seabrook Station Tunnels--No audiometric testing for overexposed employees." _ISSUES AND JURISDICTION_: The Respondent engages in interstate commerce within the meaning of the Occupational Safety and Health Act of 1970. It did not contest the jurisdiction of the Commission over the instant matter; therefore, the Commission assumes that jurisdiction by law. The issues before the undersigned judge concern whether or not the Respondent violated the regulations as alleged. _EVIDENCE_ Mr. David C. May, a compliance officer for the United States Department of Labor, Occupational Safety and Health Administration (OSHA) was the Complainant's first witness. (Tr. 20) He is an industrial hygienist (Tr. 21) and he visited the Seabrook Power Station, Seabrook, New Hampshire, on October 30, 1979 (Tr. 24) and October 31, 1979 (Tr. 24) and inspected the tunnels. (Tr. 26) Mr. May took an elevator down into a cavern opening to get to the tunnels which were approximately two hundred fifty feet below the surface and about one mile long. (Tr. 26) On October 30, 1979, there was no moling (excavating), but Mr. May rode the locomotive out to the mole site. (Tr. 26-27) Upon his return on October 31, 1979, he continued his inspection. (Tr. 27) On that date, he conducted some screening gas tests and noise tests in both tunnels (Tr. 28). The mole was not operating at the time but the locomotive was. (Tr. 28). For the noise screening tests he used a Type Two General Radio sound level meter which gave him an instantaneous look at the noise level. (Tr. 29) He performed those tests to determine whether further sampling was needed on the trailing section of the mole. (Tr. 29-30) He informed the Respondent of his desire to take full shift samplings. (Tr. 31) He returned to the work site on November 30, 1979 (Tr. 31), took some samplings (Tr. 50), and arranged to return on December 4, 1979. The employee sampled on November 30, 1980, was not overexposed. (Tr. 50-51) Due to a fatality, the inspection was postponed until December 13, 1979. (Tr. 51-52) On the latter date, the sampling was of the second shift in Tunnel 173. (Tr. 52) After calibrating his dosimeters in the Respondent's (Mr. Jones') office, Mr. May requested employees from Tunnel 173 that included two locomotive drivers, a car pass operator, a mole operator, a rock driller and a brakeman (Tr. 53) so that he could obtain noise samples. (Tr. 65) He used two instruments to measure the noise exposure, i.e., a dosimeter which records the intensity and duration of noise as well as a General Radio Type 1 sound level meter, which gives instantaneous readings at any one spot as to how loud it is. (Tr. 65-66) The dosimeter records on the A scale and perceives noise similar to that of an ear whereas the sound level meter measures how loud noise is at certain frequences. (Tr. 65-66) On December 13, 1979, he attached dosimeters to a locomotive driver and a car pass operator in tunnel 173 by placing the instrument in the wearer's belt and running the wire up to the collar where the microphone was attached. (Tr.67) This procedure was used in order to get as close as possible to the employee's hearing zone. (Tr. 67) Mr. May also took readings with a hand sound level meter (Tr. 69, 76-77) while riding right behind the locomotive driver and obtained a decibel (DBA) reading of 105 which he opined was "fairly high". (Tr. 73, 77) The driver took about twelve round trips daily per shift, each one-way trip lasting approximately five minutes. (Tr. 73) Mr. May testified that the employee was not wearing hearing protection. (Tr. 76) He was primarily in tunnel 173 (Except for 1 employee tested in tunnel 174) during the full shift and made visual walk arounds, took sound level meter readings as well as gas and dust readings. (Tr. 101) He recorded results about once per hour. (Tr. 101) He testified to a dosimeter reading of 217 percent (Exhibit C-8) over a period of more than eight hours for the driver of a locomotive in tunnel 174 (Tr. 102-103), but admitted that there is a 30-32 percent error factor. (Tr. 103) He stated that an employer is not cited unless a reading is greater than 132 percent so as to allow for the margin of error. (Tr. 103) He sampled the brakeman, Warren Kimball (Exhibit C-10) and the results were 378.1 percent of the OSHA standard. (Tr. 115-117) On Exhibit C-12, he recorded a 250.3 percent exposure in 5 hours 24 minutes to Ronnie Deheitas, the mole operator in Tunnel 173. (Tr. 118, 127, 129, 135) On December 13th, he also sampled for about 5 hours Leo Paradis, the car pass operator in Tunnel 173 (Exhibit C-14) and recorded 150 percent of the OSHA standard (Tr. 137, 144, 146, 147). Exhibit C-16 showed 304.8 percent of the OSHA standard as a result of 8 hours of sampling on December 13th of John J. Shield's Jr., the motorman of Tunnel 173 (Tr. 150, 152). Exhibit C-18 recorded 999 percent for a 5 hour sampling on December 13th of George Demers, a rock driller in Tunnel 173. Mr. May testified that he observed Vic Allard, the walker (foreman) on the mole without hearing protection as well as an electrician and carpenter. (Tr. 105-107, 150, 152, 232, 240, 242, 257, 258 and Exhibit C-21). As a result of his inspection, Mr. May recommended that the over exposed employees have hearing protection, that feasible engineering controls and a hearing conservation program be instituted. (Tr. 268) He also recommended that a serious citation be issued because "noise induced hearing loss is a permanent loss of hearing, which cannot be recovered..." (Tr. 268) When looking at factors considered for proposed penalty he indicated that he found that the Respondent employed more than 100 people, did not have a previous history of prior violations within his area office, and showed a willingness to assure employees would wear hearing protection. (Tr. 271) Regarding item 1A of the serious citation, the personal protective equipment required by Mr. May was available on site so an abatement date of immediately was selected. (Tr. 275-276) As to Item 1B, he recommended a period of two months (Tr. 276-278) in order for the Respondent to submit its plan for abatement and another two months to furnish the preliminary surveys indicating which feasible engineering or administrative controls to use. (Tr. 278) Mr. May testified that he chose time frames based on his previous experience in noise cases. (Tr. 279) As to actual implementation of feasible administrative or engineering controls, he felt that six months from the time of the issuance of the citation would be reasonable, as it would be two months after the engineering reports were completed. (Tr. 279) He admitted that the latter date was difficult to pinpoint, acknowledging possible problems with contractors, etc. (Tr. 280, 282) He discussed enclosing the car pass operator's work station (Exhibit C-28) the hydraulic motor noise source and the costs of such enclosure. (Tr. 282, 283, 288) Mr. May testified that his research had indicated it would be technically feasible to place a booth around the car pass operator and that estimated cost would be $3,000.00 for two booths. (Tr. 289-290) As for the mole operator in tunnel 173, he indicated that a booth could be installed (Tr. 296-297, Exhibits C-25, C-26), and estimated the material cost per booth to be $1,900.00 (Tr. 298). He stated that a theoretical reduction of about 35 decibels was predicted for his proposal as regards to the mole operator. (Tr. 300) His testimony concerning noise reduction for the rock drillers indicated the use of mufflers, muffler jackets and/or dampening materials. (Tr. 301), and Exhibit C-33 was introduced to demonstrate feasibility of such controls for drills. (Tr. 307, 311) Exhibit C-34 depicts a locomotive at the site (Tr. 315) and Mr. May suggested installing a cab over where the operator and brakeman ride or enclosing the transmission. (Tr. 316-317) The cab should, according to the witness, be made from noise reduction materials (Tr. 316), and he didn't believe the operation of the locomotive would be obstructed by the cab but had no knowledge as to the effect of enclosing the transmission on the operation. (Tr. 317) The estimated cost of the enclosure would be $1,150.00 per locomotive. (Tr. 319) As to item 1C of the serious citation, which concerned the hearing conservation program he recommended thirty days for abatement and required a four point program including base line audiograms for over-exposed employees. (Tr. 320, 325, 326) The guidelines he used came from the Industrial Hygiene Field Operations Manual. (Tr. 322, Exhibit C-35) On cross examination, Mr. May admitted that all employees except those in booths or enclosures would have to wear hearing protection. (Tr. 383) He also testified that the type of hearing plugs he wore at the time of the inspection afforded him insulation of 30-40 decibels, according to the manufacturer and that there were ways to actually verify that. (Tr. 385) The cost of the plugs was about thirty cents per pair (Tr. 387), and they were effective in reducing the noise (Tr. 392) but that he was concerned that employees might not wear them daily or properly. (Tr. 391) He stated that they could become dirty from the environment so an employee might be tempted to throw them out after a day's use although they could be cleaned and reused. (Tr. 392-393). The proposed booths had at best a theoretical estimate of 35 decibel reduction, which was about the same protection afforded by the ear protectors he wore. (Tr. 384, 389) He had no information nor could he obtain any regarding the actual decibel reduction that would be obtained by the use of such booths. (Tr. 385, 386) As to commercially produced ear muffs, Mr. May indicated that the resultant reduction could be as much as 50 decibels, the cost would be about ten to fifteen dollars, and they would last for the duration of the project. (Tr. 395-396) He admitted that not only would they reduce noise to a greater degree than the proposed enclosure but that the cost would be considerably less. (Tr. 396, 398) While conducting his inspection, Mr. May wore a raincoat and work boots as the tunnels are wet with constant moisture in the air. (Tr. 402-403) His testimony indicated that the OSHA Industrial Hygienist Field Operations' Manual warned that the dosimeters would perform accurately as long as moisture does not condense or deposit on the microphone diaphragm. (Tr. 407) For the noise samplings, the microphone were placed on the six employees' collars but not covered by their raincoats. (Tr. 408, 415) Normally the best placement of the microphone would be the center of the shoulder in order to pick up noise coming up from behind, in front and to the side (Tr. 412); however, he placed the microphones on the collar in order to protect them from water dripping in the tunnel, which placement admittedly was not the optimum location. (Tr. 413) He testified that dosimeters don't record until the noise level is above 90 decibels (Tr. 760-764) and a 2 decibel margin of error is allowed (Tr. 963) If the diaphragm of the microphone got wet, it would lower the results (Tr. 967-968) and the fact that the site was 258 feet below sea level only meant a difference of 0.34 decibels (Tr. 973). Mr. May stated that out of the 330 Morrison-Knudsen employees at the site, he saw 3 without hearing protection on December 13, 1979 (Tr. 496-497). He made no inquiries as to whether or not the Respondent provided hearing protection, (Tr. 498-500); however, Mr. David stated to him that they were available in various locations. (Tr. 500-501). Mr. May's contention in citing the Respondent was that it did not insure that the employees wore them in high noise areas (Tr. 502-518) and he suggested that a person be responsible for that. (Tr. 504) He testified that the fact that some employees wore hearing protection and others did not indicated to him there were deficiencies in the safety program but admitted he didn't know about the program. (Tr. 518-520) The basis for his opinion that there was improper supervision rested solely on the fact that he saw Vic Allard, the walker supervisor, not wearing them (Tr. 521) Mr. May suggested periodic audiometric testing for overexposed employees. (Tr. 547, 555, 557-559) Mr. Jerry Antel, an engineering technician with the Mine Safety and Health Administration (Tr. 1041) renders assistance to the mining industry to reduce noise exposure (Tr. 1042). He analyzes a problem from the health and engineering aspects (Tr. 1042). His experience included evaluating a diesel locomotive similar to the one used at the Respondent's work site at the time of the inspection and found that the transmission was the primary noise source. (Tr. 1049) He stated that an enclosure was actually installed around the transmission with noise absorption materials resulting in about 8-10 decibel reduction which brought it within the allowable limits. (Tr. 1050, 1051, 1068) In order to know the actual absorption materials needed, tape recordings of the noise would have to be made. (Tr. 1094) Mr. Antel opined that the major source of noise for the drills used at the Respondent's site was the exhausting air and the attachment of a body muffler would achieve a 7-8 decibel reduction. According to him, there was no freezing encountered nor any significant drilling restriction from the body muffler. (Tr. 1331) Regarding the booths for the locomotives and car pass operator, Mr. Antel testified that the window could be slanted to be closer at the bottom then at the top (Tr. 1333) and it should be made of lucite. (Tr. 1335) Mr. Orville Jones, the senior safety supervisor for the Respondent at the site (Tr. 1122) testified that the built-in circulatory system would be destroyed if the car pass (Tr. 1181) or mole operator were enclosed (Tr. 1168-69), and that the use of air conditioning would not be possible due to the electrical capacity in the tunnel. (Tr. 1170-71) He cited visual problems due to mud and scratching of the enclosure (Tr. 1175) and clearance problems on the locomotives. (Tr. 1185, 1189, 1193, 1267, 1269). He complained of diminished efficiency if mufflers were put on the drills. (Tr. 1199). _DISCUSSION_ The Secretary of Labor bears the burden of proving the existence of a violation by a preponderance of the evidence. _Astra_ _Pharmaceutical Products, Inc._, 9 BNA OSHC 2126 (1981). In the case at hand, the Secretary must prove that administrative or engineering controls for reducing employee exposure are technically and economically feasible. _Secretary of Labor v. Continental_ _Can Company_, 4 OSHC 1541, 1548 (1976). The cost benefit test enunciated by the Commission appears to still be the law for noise cases, see _Continental Can Company_, _supra_, despite the United States Supreme Court decision in _American Textile_ _Manufacturers Institute Inc_. _et al v. Donovan et al_ (June 17, 1981) which ruled on the interpretation of Section 6(b)(5) of the Occupational Safety and Health Act (29 U.S.C. Section 655(b)(5). To determine whether something is technologically feasible, there must exist a type of control capable of producing a significant reduction in noise exposure in the Respondent's workplace and the Secretary must show that such technology could be adapted to the employer's workplace. _Secretary of Labor v. Samson Paper Bag Company, Inc._, 8 OSHC 1515 (1980). There is no duty on each employer to research and develop new technology, _American Iron and Steel Institute et al v. OSHA_, 6 OSHC 1451, 1461 (1978). A Respondent is only in violation of the standard if it fails to implement technological controls feasible at the time it was cited, see _Samson Paper Bag Company, Inc._, supra at 1519. "The standard provides that administrative or engineering controls shall be the preferred means of compliance, with personal protective equipment to be used if such controls are not "feasible" or if the controls that are feasible cannot achieve full compliance." _Samson Paper Bag Company, Inc_. supra at 1518, see also _Secretary of Labor v. Turner Corp_., 4 OSHC 1554, 1557 (1976). In the _Samson Paper Bag_ case, the employees were wearing earplugs capable of reducing noise exposure to within the permissible exposure levels. The use of personal protective devices which in fact reduce the noise exposure to within allowable limits can not excuse the employer from its responsibility to adhere to technological advances if they exist but use of the devices must be considered to determine whether the resultant harm will be serious or nonserious. In the instant case, the testimony is uncontroverted that such devices exist and are available and in use at the Respondent's workplace in issue; therefore, the harm that could result here is non-serious. The Respondent raises the issues of the proper use of the dosimeters and the time lapse of their use after sound level tests were taken. The testimony reveals that there were no sound level tests performed at the time the dosimeters were placed on the employees and the Respondent questions the reliability of the dosimeter readings because the compliance officer did not constantly watch the employees to know if the readings resulted from the particular work stations for which the Secretary wants engineering controls or from other locations. Furthermore, the Respondent raises the issue of readings taken for less than eight hours and refers to _Secretary of Labor v. Gannett Rochester Newspaper Corporation_ 9 OSHC 1590 (1981) to support his contention. In the latter case, dosimeters weren't used in conjunction with the sound level meters and the compliance officer failed to keep the employees under constant control. Certainly there are problems in this instant case for requiring engineering controls for the mole operators, car pass operators and locomotive drivers. In one instance, the compliance officer didn't even observe the employee at work. There are further problems that arise due to the lack of technological feasibility of the items proposed or "suggested" by the Secretary for those work stations. There was no evidence that indicated that such booths would be feasible or effective in the Respondent's workplace. The compliance officer had never before inspected such a tunnel and Mr. Antel's testimony on that point was tenuous. This can be distinguished however from Mr. Antel's testimony which referred to his experience with comparable use of similar drills and the availability of mufflers for those drills to reduce noise levels. His answers to problems that could arise from the use of mufflers certainly indicate they are technologically and economically feasible in the instant case, and the compliance officer's testimony for that violation is credible and reliable. The testimony adduced revealed that the noise levels to which the Respondent's rock drillers were exposed exceed the permissible levels and that the employer knew or with the exercise of reasonable diligence could have known those facts. The Secretary's testimony consisting of the compliance's officers observation of a few employees without hearing protection does not meet the burden of proof that those employees were exposed for the time required to any levels that exceed the requirements of Table D-2. The last part of the citation (Item 1C) concerns the hearing conservation program and the Respondent has raised the issue that the standard is constitutionally vague as it does not provide proper notice to the employer of what's required. The alleged violation of 29 C.F.R. 1926.52(d)(1) is identical to 29 C.F.R. 1910.95(b)(3) which standard was recently declared by the Seventh Circuit in _Kropp Forge Company v. Secretary of Labor and OSHRC_, 9 OSHC 2133, 2134, (August 14, 1981) to be unenforceably vague. The court stated that this was so because the standard did not provide "fair warning" of what is required or prohibited. The Seventh Circuit referred to the United States Supreme Court decision in _American Textile Manufacturers Institute Inc. v_. _Donovan_, _supra_ and reiterated the predicate for agency action". The _Kropp Forge_ case at 2135 noted that on January 16, 1981 OSHA removed the one-sentence standard at issue and replaced it with a new regulation which thus acknowledged that the elements required by the Secretary in _Kropp Forge_ were not previously included in the standard cited. This reasoning is completely applicable to the instant case; thus, 29 C.F.R. 1926.52(d)(1) must be found to be unenforceably vague. _FINDINGS OF FACT_ 1. Compliance Officer David C. May made a duly authorized and proper inspection of the Respondent in the instant case at the Seabrook Power Station, Seabrook, New Hampshire. 2. The Respondent is found to have been engaged in tunnel construction at the time of the inspection. 3. The Respondent is found to have contested Items 1A, 1B and 1C of the Serious citation. 4. The Respondent is found to be a large company. 5. At the rock drillers work stations, the said employees were exposed to noise levels exceeding those permitted by Table D-2. 6. The Respondent knew, or with the exercise or reasonable diligence could have known that the noise levels were excessive at the rock drillers' work stations. 7. Use of mufflers of drills for the violation of Item 1B is found to be required and to be economically and technologically feasible. _CONCLUSIONS OF LAW_ 1. At all times relevant herein, the Respondent has been engaged in a business affecting commerce within the meaning of Section 3 of the Occupational Safety and Health Act of 1970. 2. The Respondent was, at all times relevant hereto, subject to the requirements of the Occupational Safety and Health Act of 1970 and the Standards promulgated thereunder. 3. The Commission, at all times relevant hereto, has had jurisdiction of the parties and of the subject matter herein. 4. The Respondent did not fail to comply with 29 C.F.R. 1926.52(a). 5. The Respondent failed to comply with 29 C.F.R. 1926.52(b) in so far as it applies to the drills, the rock drillers and the utilizing of feasible engineering controls for the said drills, but it did not fail to comply with said standard as to the balance of the work stations and employees tested. 6. The Respondent's failure to comply with 29 C.F.R. 1926.52(b) is non-serious due to the employees' use of hearing protection. 7. The Respondent did not fail to comply with 29 C.F.R. 1926.52 (d)(1) as that standard is unenforceably vague. _ORDER_ 1. Serious citation, Item 1A is vacated. 2. Serious citation, Item 1B is affirmed as to the rock drillers and drills and no penalty is assessed. 3. Mufflers are required for the drills used at the Respondent's worksite as regards to Serious citation, Item 1B. 4. Serious citation, Item 1C is vacated. BARBARA L. HASSENFELD JUDGE, OSHRC Dated: January 7, 1982 Boston, Massachusetts FOOTNOTES: [[1]] The section 1926.52(a) allegation is contained in item 1A of a citation issued to Morrison-Knudsen by the Secretary of Labor. The Commission previously granted the Secretary's motion to withdraw item 1B of the citation, which alleged that Morrison-Knudsen failed to use feasible engineering or administrative controls to reduce noise levels. Also, the Secretary has not taken exception to the judge's decision to vacate item 1C, which alleged that the company failed to implement a hearing conservation program. [[2]] The compliance officer testified that Shields was not wearing hearing protection at 9:27, when he took a reading from the dosimeter Shields was wearing. The officer was somewhat equivocal about whether he observed Shields without hearing protection at 9:31, ultimately stating that Shields was not wearing the equipment "to the best of my recollection." The compliance officer's data sheet for Shields has an entry "No PPE [personal protective equipment]" for the 9:27 observation but does not have a similar entry for the 9:31 observation. The data sheet also does not indicate whether Shields was wearing protective equipment at the other times he was observed by the compliance officer. [[3]] At the time this case was tried, Commission Rule 52, 29 C.F.R. § 2200.52, permitted requests for admissions. The Commission's rules of procedure have since been amended, and requests for admissions are now addressed in Rule 54, 51 Fed. Reg. 32002, 32023 (Sept. 8, 1986) to be codified at 29 C.F.R. § 2200.54. [[4]] To prove that an employer violated a standard, the Secretary must show that the employer knew or could have known, with reasonable diligence, of the existence of the violation. Here, the Secretary would have to prove that Morrison-Knudsen had actual or constructive knowledge that employees exposed to excessive noise were not wearing hearing protection equipment. Because we conclude that the Secretary did not establish that Morrison-Knudsen's employees were not wearing the equipment for the required amount of time, we need not reach whether the company had the knowledge needed to find a violation. We note, however, that there is no evidence that Morrison-Knudsen had actual knowledge that Shields and Grondin were not wearing hearing protection. Moreover, of 75 to 100 employees working in the tunnel during the inspection, all but 2 or 3 were wearing hearing protection. The achievement of such a high degree of compliance is a strong indication that the company adequately communicated and enforced a work rule requiring that hearing protection equipment be worn and did not have constructive knowledge of the few instances of noncompliance. _See_ _I. T. O. Corp. of Ameriport_, 83 OSAHRC 35/C4, 11 BNA OSHC 1562, 1983 CCH OSHD ¶ 26,583 (No. 80-2369, 1983); _Daniel Construction Co. of Alabama_, 81 OSAHRC 71/A2, 9 BNA OSHC 2002, 1981 CCH OSHD ¶ 25,553 (No. 13874, 1981). [[5]] Because of our disposition, we do not reach the other issue raised by Morrison-Knudsen in arguing that the item should be vacated.