               IN THE SUPREME COURT OF IOWA
                           No. 142 / 05-0740

                         Filed February 16, 2007

INSITUFORM TECHNOLOGIES, INC.,

      Appellant,

vs.

EMPLOYMENT APPEAL BOARD, a Unit
of the Department of Inspections and
Appeals, and LABOR COMMISSIONER,

      Appellees.


      On review from the Iowa Court of Appeals.



      Appeal from the Iowa District Court for Polk County, Karen A.

Romano, Judge.



      The employer, employment appeal board, and labor commissioner

appeal from a district court ruling on a petition for judicial review.

DECISION OF COURT OF APPEALS VACATED; DISTRICT COURT

JUDGMENT REVERSED AND CASE REMANDED.



      Mark A. Lies II and James L. Curtis of Seyfarth Shaw, LLP, Chicago,

Illinois, and Joan M. Fletcher of Dickinson, Mackaman, Tyler & Hagen,

P.C., Des Moines, for appellant.



      Rick Autry, Des Moines, and Gail Sheridan-Lucht, Des Moines, for

appellees.
                                       2

WIGGINS, Justice.

      The sewer-relining accident causing the Iowa occupational safety and

health (IOSH) bureau to cite Insituform Technologies, Inc. for nine serious

violations and eleven willful violations of the IOSH standards is the same

accident described in City of Des Moines v. Employment Appeal Board, 722

N.W.2d 183, 187-88 (Iowa 2006). As a result of that accident, two people

died and five people were seriously injured. The IOSH bureau proposed

$38,250 in penalties for the nine serious violations and $770,000 in

penalties for the eleven willful violations for a total of $808,250 in penalties.

      Insituform filed a notice of contest to the citation and the matter was

transferred to the employment appeal board (Board). The Board assigned

the matter to an administrative law judge (ALJ) for a hearing. The ALJ

applied the general industry permit-required confined spaces standards, as

found in 29 C.F.R. section 1910.146. He affirmed most of the penalties, but

modified, dismissed, and combined some of the others. The ALJ reduced

the penalties from $808,250 to $158,000.

      Insituform appealed the decision of the ALJ to the Board. The Board

adopted the ALJ’s findings of fact and the ALJ’s determination that the

general industry permit-required confined spaces standards rather than the

construction employment standards applied to the work done by Insituform.

The Board disagreed with the ALJ’s dismissal of some violations and his

reduction of the penalties. The Board reinstated all but one of the serious

violations and all but one of the willful violations and assessed a total

penalty of $733,750.

      Insituform filed a petition for judicial review.      The district court

affirmed the Board’s decision applying the general industry permit-required

confined spaces standards rather than the construction employment
                                     3

standards. However, the district court reinstated the ALJ’s assessment and

grouping of the violations and penalties. The total penalty assessed against

Insituform by the district court was $158,000.

      Insituform, the Board, and the commissioner appealed the decision of

the district court. We transferred the case to the court of appeals. Relying

on its decision in City of Des Moines v. Employment Appeal Board, No.

04-1763, 2006 WL 127955, at *4-*5 (Iowa Ct. App. Jan. 19, 2006), the court

of appeals held the general industry permit-required confined spaces

standards were not applicable. The court of appeals then dismissed all but

two of the serious violations and all of the willful violations because the

commissioner based these violations on the general industry permit-

required confined spaces standards. The court of appeals affirmed the

district court’s combination of the penalties for the remaining serious

violations reducing the total penalty to $4500.

      The Board and the commissioner sought further review, which we

granted.

      I. Issues.

      There are four issues on appeal: (1) whether the Board erred in

applying the general industry permit-required confined spaces standards to

the work done by Insituform; (2) whether the application of these standards

is constitutional; (3) whether substantial evidence supports the Board’s

determination that Insituform violated the standards; and (4) whether the

district court erred in combining the civil penalties assessed by the Board.

      II. Scope of Review.

      The Iowa Administrative Procedure Act governs a district court’s

review of administrative action. IBP, Inc. v. Harpole, 621 N.W.2d 410, 414

(Iowa 2001) (citing Iowa Code § 17A.19(8)). When reviewing the decision of
                                            4

the district court’s judicial review ruling, we determine if we would reach

the same result as the district court in our application of the Iowa

Administrative Procedure Act. City of Des Moines, 722 N.W.2d at 189-90.

If a decision of the agency is incorrect under a ground specified in the Act,

and a party’s substantial rights have been prejudiced, the district court may

reverse or modify an agency’s decision. Iowa Code § 17A.19(10) (2001). As

we discuss each issue raised on appeal, we will note the applicable scope of

review.

       III. Analysis.

       A. Whether the Board erred in applying the general industry permit-

required confined spaces standards to the work done by Insituform. Because

the legislature gave the labor commissioner the authority to interpret the

IOSH standards, we will only reverse the agency’s interpretation of its

standards if it is “irrational, illogical, or wholly unjustified.” City of Des

Moines, 722 N.W.2d at 193-94 (citing Iowa Code §§ 17A.19(10)(l), (11)(c)).

       In City of Des Moines, we agreed with the Board’s interpretation that

in order to determine whether the general industry permit-required confined

spaces standards or the construction employment standards apply, the

Board must determine, on a case-by-case basis, whether the task being

performed is maintenance or repair. 1 Id. at 194. If the Board determines
the task is maintenance, then the general industry permit-required confined

spaces standards apply. Id. If the Board determines the task is repair, then

the construction employment standards apply. Id. We also stated, “[i]f the

question is close as to whether the work constitutes repair or maintenance,

the agency should apply the standards that provide more protection to the

       1The  general industry permit-required confined spaces standards are contained in
29 C.F.R. section 1910.146, as incorporated into Iowa law by Iowa Administrative Code rule
875—10.20. The construction employment standards are contained in 29 C.F.R. part
1926, as incorporated into Iowa law by Iowa Administrative Code rule 875—26.1.
                                     5

employees, depending on the hazard.” Id. In the present case, the ALJ

found the general industry permit-required confined spaces standards

applied to the sewer-relining project, and interpreted these standards using

the same analysis as we did in City of Des Moines. The Board adopted these

findings as its own. Because the ALJ, and hence the Board, employed the

proper analysis to interpret the applicable standards, the Board’s

interpretation was not irrational, illogical, or wholly unjustifiable.

Accordingly, we will not reverse the Board’s interpretation.

      As a case-by-case analysis of the facts is necessary to determine

whether the work being performed is maintenance or repair, it is necessary

for us to determine if substantial evidence supports the Board’s analysis

and finding that the work done in the sewer was maintenance.               If

substantial evidence supports the Board’s findings, these findings are

binding on us. United Fire & Cas. Co. v. St. Paul Fire & Marine Ins. Co., 677

N.W.2d 755, 759 (Iowa 2004).

      In City of Des Moines, we held substantial evidence supported the

Board’s decision that the work done by Insituform on the sewer project was

maintenance; therefore, the general industry permit-required confined

spaces standards were applicable to that work. City of Des Moines, 722

N.W.2d at 194-95. The record in this case contains substantially the same

evidence as was introduced in City of Des Moines. Consequently, for the

reasons stated in City of Des Moines, we find substantial evidence exists in

this record to affirm the Board’s decision that the work done by Insituform

on the sewer project is governed by the IOSH general industry permit-

required confined spaces standards.

      B. Whether the application of the general industry permit-required

confined spaces standards is constitutional.      When a party raises a
                                      6

constitutional issue in an appeal of agency action, our review is de novo.

ABC Disposal Sys., Inc. v. Dep’t of Natural Res., 681 N.W.2d 596, 605 (Iowa

2004). Thus, we apply a de novo review to Insituform’s claim that the

Board’s application of the general industry permit-required confined spaces

standards is unconstitutional.

      Insituform claims the commissioner failed to provide fair warning and

“prior clear regulatory guidance to Insituform and others” indicating when

an employer is subject to the specific requirements of the general industry

permit-required confined spaces standards. Insituform states because of

this lack of fair warning and the vagueness contained in the standards, the

commissioner’s application of the general industry permit-required confined

spaces standards to Insituform violates the Due Process Clause of both the

United States Constitution and the Iowa constitution.

      Due process requires that “no person shall be deprived of life, liberty,

or property, without due process of law.” Iowa Const. art. I, § 9; U.S. Const.

amends. V, XIV, § 1. Both the federal and state Due Process Clauses

prohibit vague statutes. State v. Todd, 468 N.W.2d 462, 465 (Iowa 1991). A

civil statute is unconstitutionally vague when the language of the statute

fails to convey a definite warning of the proscribed conduct. ABC Disposal

Sys., Inc., 681 N.W.2d at 605. A statute is not unconstitutionally vague if

its meaning can be ascertained by reference to “generally accepted and

common meaning of words used, or by reference to the dictionary, related or

similar statutes, the common law, or previous judicial constructions.” Id.

“To avoid a rule from unduly restricting the regulation of certain matters, a

certain degree of indefiniteness is necessary.” Id. Finally, “[t]here is a

presumption of constitutionality and a litigant can only rebut this
                                      7

presumption by ‘negating every reasonable basis on which the statute can

be sustained.’ ” Id. (citation omitted).

      Insituform argues it was unable to identify with “ ‘ascertainable

certainty’ that the Commissioner expected it to conform to the more detailed

requirements of the general industry confined spaces standards.” The

commissioner argues, as this court found in City of Des Moines, Insituform

was not engaged in the construction of new sewers, but rather was

participating in a sewer-relining project. Therefore, our court concluded

Insituform was doing maintenance work.

      As we discussed in City of Des Moines, a 1995 OSHA instruction and

a 1996 standard interpretation specifically explained sewer relining is

covered by the general industry permit-required confined spaces standards.

See City of Des Moines, 722 N.W.2d at 190-92.          The instruction and

standard interpretation gave Insituform fair warning of the applicability of

the general industry permit-required confined spaces standards to sewer-

relining projects.

      There is additional evidence in the record supporting that Insituform

had fair warning and was on notice the general industry permit-required

confined spaces standards applied to the sewer-relining project. First,

Insituform used the general industry permit-required confined spaces

standards to formulate its safety manual policies. Second, the J.J. Keller

employee handbook used by Insituform to train its employees specifically

lists “sewers” as an example of a confined space. See Ohio Cast Prod., Inc. v.

Occupational Safety & Health Review Comm'n, 246 F.3d 791, 798-99 (6th

Cir. 2001) (finding industry practice is significant in determining whether a

fair warning was given to an employer). Third, Insituform’s safety handbook

specifically lists 29 C.F.R. section 1910.146 and appendices A, B, and C to
                                      8

29 C.F.R. section 1910.146 as guidance documents.           Appendix C lists

“sewer entry” as an example of a permit-required confined space. 29 C.F.R.

§ 1910.146 app. C. As the area safety manager for Insituform, Herbert

Young, testified 29 C.F.R. section 1910.146 “addresses the best practice for

entering sewers.” Fourth, the City of Des Moines described the project as a

sewer-relining project in its notice to bidders and notice of public hearing.

Fifth, while at the site, Insituform employees filled out “confined space entry

permits” attempting conformity with 29 C.F.R. section 1910.146(e)(1).

Sixth, after the fatal accident, Insituform issued seven written warnings to

its employees who were on site that day for violation of Insituform’s

“confined space entry policy,” which was formulated by Insituform under 29

C.F.R. section 1910.146.

      Finally, Insituform argues because the district court in City of Des

Moines found the general industry permit-required confined spaces

standards did not apply to the sewer project while the district court in this

case found the general industry permit-required confined spaces standards

did apply, the application of these standards is unconstitutionally vague.

We disagree.    Merely because two different officials applying the same

factors reach a different interpretation of a statute does not render that

statute unconstitutionally vague. See State v. Holway, 644 N.W.2d 624,

629 (S.D. 2002) (stating “[a] law is not rendered unconstitutionally vague

merely because the decision of one official applying the factors is different

from that of another official applying those same factors”).

      Accordingly, Insituform’s claim that the commissioner failed to

provide fair warning and “prior clear regulatory guidance to Insituform and

others” indicating when an employer is subject to the specific requirement

of the general industry permit-required confined spaces standards is
                                     9

unfounded.    Therefore, the Board’s application of these standards to

Insituform’s sewer-relining project is constitutional.

      C. Whether substantial evidence supports the Board’s decision as to

Insituform’s violation of the standards. If our review of the record reveals

substantial evidence supports the Board’s findings as to the violations, the

findings are binding on us. United Fire & Cas. Co., 677 N.W.2d at 759.

“[This court’s] inquiry is whether the evidence supports the findings made

by the agency, not whether the evidence may support a different finding.”

City of Des Moines, 722 N.W.2d at 195.

      The Iowa Code authorizes the commissioner to adopt and promulgate

occupational safety and health standards that the United States secretary of

labor adopted and promulgated as permanent standards.            Iowa Code

§ 88.5(1)(a). Pursuant to this authority, the commissioner adopted the

federal respiratory protection standards found at 29 C.F.R. section

1910.134 and the federal permit-required confined spaces standards found

at 29 C.F.R. section 1910.146. See Iowa Admin. Code rs. 875—26.1, 10.20.

Accordingly, all citations issued by the IOSH bureau to Insituform are for
violations of the federal OSHA standards.

      1. Does substantial evidence support the violation of the standards as

found by the Board in citation one? In citation one, the commissioner alleged

Insituform committed nine serious violations. The Board found Insituform

only committed eight serious violations. If substantial evidence supports a

violation of the standard, we will then determine if substantial evidence

supports the Board’s determination that the violations were serious

violations as defined under the Code.

      a. Citation one, item one. The Board found Insituform committed a

serious violation by not establishing and implementing worksite-specific
                                        10

written standard operating procedures governing the selection and use of

respirators, violating 29 C.F.R. section 1910.134(c)(1). The standard states:

      (c) This paragraph requires the employer to develop and
      implement a written respiratory protection program with
      required worksite-specific procedures and elements for
      required respirator use. The program must be administered by
      a suitably trained program administrator. In addition, certain
      program elements may be required for voluntary use to prevent
      potential hazards associated with the use of the respirator.

      (1) In any workplace where respirators are necessary to protect
      the health of the employee or whenever respirators are required
      by the employer, the employer shall establish and implement a
      written respiratory protection program with worksite-specific
      procedures. The program shall be updated as necessary to
      reflect those changes in workplace conditions that affect
      respirator use. The employer shall include in the program the
      following provisions of this section, as applicable:

      (i) Procedures for selecting respirators for use in the
      workplace;

      (ii) Medical evaluations     of    employees   required       to   use
      respirators;

      (iii) Fit testing procedures for tight-fitting respirators;

      (iv) Procedures for proper use of respirators in routine and
      reasonably foreseeable emergency situations;

      (v) Procedures and schedules for cleaning, disinfecting,
      storing, inspecting, repairing, discarding, and otherwise
      maintaining respirators;

      (vi) Procedures to ensure adequate air quality, quantity, and
      flow of breathing air for atmosphere-supplying respirators;

      (vii) Training of employees in the respiratory hazards to which
      they are potentially exposed during routine and emergency
      situations;

      (viii) Training of employees in the proper use of respirators,
      including putting on and removing them, any limitations on
      their use, and their maintenance; and

      (ix) Procedures for regularly evaluating the effectiveness of the
      program.
                                     11

29 C.F.R. § 1910.134(c)(1). Substantial evidence supports the Board’s

finding that Insituform violated this standard.

      Chapter ten of Insituform’s safety manual contained a written

program that governed the selection and use of respirators. Insituform

wrote its respiratory protection program in accordance with 29 C.F.R.

section 1910.134. However, Insituform did not implement this plan. James

Johnson, a laborer for Insituform, testified workers never used respirators

on the job site. When he was asked to explain his answer, he testified, “just

never.” John Walkenhorst, also a laborer for Insituform, testified on the day

of the accident no one was wearing a respirator. Further, Bill Bull, the crew

leader, testified he was not familiar with Insituform’s safety manual and the

manual was not a part of any Insituform safety training.

      b. Citation one, item three. The Board found Insituform committed a

serious violation by failing to fit test atmosphere-supplying respirators and

tight-fitting powered air-purifying respirators by performing quantitative or

qualitative fit-testing in the negative pressure mode, violating 29 C.F.R.

section 1910.134(f)(8).

      After the accident, Bull entered the sewer to remove the sewer plug

while wearing a respirator he was not fit-tested for or trained to wear. Bull

entered the sewer at the request of the Des Moines fire department in what

was an emergency situation. According to Bull, if he did not release the

plug in the sewer, the job site could not be shut down.

      The standard specifically states:

      (f) This paragraph requires that, before an employee may be
      required to use any respirator with a negative or positive
      pressure tight-fitting facepiece, the employee must be fit tested
      with the same make, model, style, and size of respirator that
      will be used.

      ...
                                     12
      (8) Fit testing of tight-fitting atmosphere-supplying respirators
      and tight-fitting powered air-purifying respirators shall be
      accomplished by performing quantitative or qualitative fit
      testing in the negative pressure mode, regardless of the mode
      of operation (negative or positive pressure) that is used for
      respiratory protection.

29 C.F.R. § 1910.134(f)(8).

      There is no exception in the standard for emergency entry into a

permit-required confined space. Factually, a properly-fitted respirator is

probably more important in an emergency to protect the rescuer from the

same danger encountered by the victim being rescued.              Therefore,

substantial evidence supports the Board’s finding that Insituform violated

29 C.F.R. section 1910.134(f)(8).

      c. Citation one, item four. The Board found Insituform committed a

serious violation by not informing exposed employees of the existence and

location of and the danger posed by the permit-required confined space by

posting danger signs or by any other equally effective means of notification,

violating 29 C.F.R. section 1910.146(c)(2). The standard states:

      (c) General requirements.

      ...

      (2) If the workplace contains permit spaces, the employer shall
      inform exposed employees, by posting danger signs or by any
      other equally effective means, of the existence and location of
      and the danger posed by the permit spaces.

      Note: A sign reading “DANGER--PERMIT-REQUIRED
      CONFINED SPACE, DO NOT ENTER” or using other similar
      language would satisfy the requirement for a sign.

29 C.F.R. § 1926.146(c)(2). Substantial evidence supports the Board’s

finding that Insituform violated this standard.

      Kent Broz, a foreman, testified he thought when the sewer was

plugged there was no need to be concerned about air quality because there

was no airflow from the sewer. Johnson testified he thought the use of
                                     13

blowers was enough to protect him from the dangerous environment. This

type of thinking indicates the employees thought the sewer was not a

permit-required confined space when the sewer was plugged.

      Bull also testified it was not his job to ensure the safety of the

employees on the job. He opined safety on the job was each worker’s

individual responsibility. Although there were signs posted on the job site

stating “Danger Keep Out,” there were no signs posted relating to warnings

about the dangers of working in the permit-required confined space.

      d. Citation one, item five. The Board found Insituform committed a

serious violation by failing to obtain any available information from the City

of Des Moines, its host employer, regarding permit space hazards and entry

operations, violating 29 C.F.R. section 1910.146(c)(9)(i).     The standard

states:

      (c) General requirements.

      ...

      (9)    In addition to complying with the permit space
      requirements that apply to all employers, each contractor who
      is retained to perform permit space entry operations shall:

      (i) Obtain any available information regarding permit space
      hazards and entry operations from the host employer.

29 C.F.R. § 1910.146(c)(9)(i). The record contains substantial evidence to

support the Board’s finding that Insituform violated this standard.

      The City of Des Moines had a safety program in place regarding

permit space hazards and entry operations. No evidence was submitted

showing Insituform obtained this information from the city before beginning

work on the sewer project. According to the commissioner’s expert, Verne

Brown, there was no communication between the City of Des Moines and
                                     14

Insituform regarding the city’s permit-required confined spaces operating

and safety procedures.

      e. Citation one, item six. The Board found Insituform committed a

serious violation by not informing its host employer, the City of Des Moines,

of the permit-required confined spaces program it would follow and of any

hazards confronted or created in the confined space through either a

debriefing or during entry operation, violating 29 C.F.R. section

1910.146(c)(9)(iii). The standard states:

      (c) General requirements.

      ...

      (9) In addition to complying with the permit space
      requirements that apply to all employers, each contractor who
      is retained to perform permit space entry operations shall:

      ...

      (iii) Inform the host employer of the permit space program that
      the contractor will follow and of any hazards confronted or
      created in permit spaces, either through a debriefing or during
      the entry operation.

29 C.F.R. § 1910.146(c)(9)(iii). The record contains substantial evidence to

support the Board’s finding that Insituform violated this standard.

      Insituform did not inform the City of Des Moines of its permit space

program. Both Brown and Iowa department of labor investigator Kenneth

Clausen were unable to find any evidence of communication between the

City of Des Moines and Insituform on these matters. The importance of this

communication is illustrated by the testimony of a Des Moines fire

department captain, Larry VanBaale. VanBaale testified his department

was never notified the sewer project was a permit-required confined space.

VanBaale further testified if he had been aware the sewer project was a

permit-required confined space he:
                                    15
      would immediately let [his] crew know that we had possible - -
      we had people working in confined space that we could be
      called to that day. We would go refresh ourselves on the SOPs
      and touch base on our proper quality - - proper entry
      techniques.

      f. Citation one, item seven. The Board found Insituform committed a

serious violation by allowing its employees to enter and work in the permit-

required confined space before Insituform prepared an entry permit,

violating 29 C.F.R. section 1910.146(e)(1). This standard states: “[b]efore

entry is authorized, the employer shall document the completion of

measures required by paragraph (d)(3) of this section by preparing an entry

permit.” 29 C.F.R. § 1910.146(e)(1). Substantial evidence supports the

Board’s finding that Insituform violated this standard.

      During the three-month period Insituform worked on the sewer, its

employees entered the sewer almost every day. However, confined space

permits were only filled out sporadically. During the entire three-month

period, only two entry permits can be accounted for and were entered into

evidence.   Walkenhorst testified he was never taught when to use the

confined space entry permit. Johnson testified he knew that a confined

space entry permit was required to enter the sewer, and although these

permits were “technically” required every day, permits were only filled out

sporadically. James Coffey, a laborer, similarly testified he knew of the

permit system, but permits were rarely used. He testified he filled out one

permit, even though he entered the sewer nearly every day.

      g. Citation one, item eight. The Board found Insituform committed a

serious violation because it did not provide its employees with training to

adequately acquire the understanding, knowledge, and skills necessary for

the safe performance of the duties of the permit-required confined spaces

standards, violating 29 C.F.R. section 1910.146(g)(1). This standard states:
                                     16

“[t]he employer shall provide training so that all employees whose work is

regulated by this section acquire the understanding, knowledge, and skills

necessary for the safe performance of the duties assigned under this

section.” 29 C.F.R. § 1910.146(g)(1). Substantial evidence supports the

Board’s finding that Insituform violated this standard.

      Although Insituform provided its employees some training, Insituform

squeezed a two- or three-day training session into one day. One worker

testified, when trained on the air monitoring devices, he never actually saw

the device, but was just provided an explanation on how to use it. The

record also supports Bull did not recognize Insituform’s safety manual. He

further testified even though he was a crew leader, he felt it was not his job

to ensure the safety of others. Additionally, Broz thought if a sewer was

plugged there was no need to worry about the atmospheric conditions.

Furthermore, the workers did not wear respirators, harnesses, or safety

equipment other than work boots and possibly hard hats.

      h. Citation one, item nine. The Board found Insituform committed a

serious violation because Insituform employees were allowed to enter and

work in the sewer access pit and sewer conduit without a chest or full-body

harness with a retrieval line properly attached, violating 29 C.F.R. section

1910.146(k)(3)(i). This standard states:

      (k) Rescue and emergency services.

      ...

      (3) To facilitate non-entry rescue, retrieval systems or methods
      shall be used whenever an authorized entrant enters a permit
      space, unless the retrieval equipment would increase the
      overall risk of entry or would not contribute to the rescue of the
      entrant.      Retrieval systems shall meet the following
      requirements.

      (i) Each authorized entrant shall use a chest or full body
      harness, with a retrieval line attached at the center of the
                                     17
      entrant’s back near shoulder level, above the entrant’s head, or
      at another point which the employer can establish presents a
      profile small enough for the successful removal of the entrant.
      Wristlets may be used in lieu of the chest or full body harness
      if the employer can demonstrate that the use of a chest or full
      body harness is infeasible or creates a greater hazard and that
      the use of wristlets is the safest and most effective alternative.

29 C.F.R. § 1910.146(k)(3)(i). Substantial evidence supports the Board’s

finding that Insituform violated this standard.

      The testimony of five Insituform employees confirms the employees

did not wear harnesses at the job site. Further, VanBaale testified none of

the men who had succumbed to the gases were wearing harnesses.

      2. Does substantial evidence support that the violations found by the

Board and affirmed by this court in citation one are serious violations? The

Code defines a serious violation. Iowa Code § 88.14(11). It provides:

      a serious violation shall be deemed to exist in a place of
      employment if there is a substantial probability that death or
      serious physical harm could result from a condition which
      exists, or from one or more practices, means, methods,
      operations, or processes which have been adopted or are in
      use, in such place of employment unless the employer did not,
      and could not with the exercise of reasonable diligence, know
      of the presence of the violation.

Id.

      The record confirms that entering a permit-required confined space,

such as this sewer, is fraught with hazards. These hazards include toxic

and flammable substances.       Many of these hazardous substances are

contained in the atmosphere and are not detectable by the human sense of

smell. Additionally, non-toxic conditions in a confined space can be deadly.

If fumes overcome a worker causing the worker to fall into a shallow puddle

of water, the puddle may contain enough water to cause the worker to

drown.
                                     18

      Considering the hazards a worker may face while in a permit-required

confined space, together with the purpose of each standard, Insituform’s

violation of each standard in citation one creates a substantial probability

that death or serious physical harm could result from the violation.

Therefore, substantial evidence exists to affirm the Board’s decision that the

eight violations it found under citation one are serious violations.

      3. Does substantial evidence support the violation of the standards as

found by the Board in citation two? In citation two, the commissioner alleged

Insituform committed eleven willful violations. The Board found Insituform

only committed ten willful violations. As with our analysis of the serious

violations, we will first determine whether substantial evidence supports a

violation of the standard. If substantial evidence supports a violation of a

standard, we will then determine if substantial evidence supports the

Board’s findings that the violations were willful violations under the Code.

      a. Citation two, item one. The Board found Insituform committed a

willful violation because Insituform did not implement the measures

necessary to prevent unauthorized entry in a permit-required confined

space, violating 29 C.F.R. section 1910.146(d)(1). This standard states:

“[u]nder the permit space program required by paragraph (c)(4) of this

section, the employer shall:    (1) Implement the measures necessary to

prevent unauthorized entry.”     29 C.F.R. § 1910.146(d)(1).     Substantial

evidence supports the Board’s finding that Insituform violated this

standard.

      According to Insituform’s safety manual the on-site superintendent,

foreman, and/or safety engineer are to control the unauthorized entry into a

permit-required confined space. Unauthorized entry would include entering

the space contrary to a written plan implemented under the provisions of
                                      19

the   permit-required   confined    spaces   standards.      See 29     C.F.R.

§ 1910.146(c)(4) (requiring the employer to “develop and implement a

written permit space program that complies with this section”).

      The record does not contain any evidence to show the on-site

superintendent, foreman, and/or safety engineer controlled entry into the

sewer.   Broz testified he did not know as the foreman it was his

responsibility to test the sewer for potential hazards and make the

determination whether to upgrade or downgrade the use of the personal

protective equipment. Further, Broz testified he thought when the sewer

work area was plugged there was no need for concern about air quality

because there was no airflow from the sewer. Finally, the record reveals

Broz received no training as a foreman. If the foreman did not know what

to look for before authorizing entry into the sewer, he could not control the

unauthorized entry into the sewer.

      b. Citation two, item two. The Board found Insituform committed a

willful violation by not adequately identifying and evaluating the hazards of

the job before allowing its employees to enter the sewer, violating 29 C.F.R.

section 1910.146(d)(2). This standard states: “[u]nder the permit space

program required by paragraph (c)(4) of this section, the employer shall: . . .

(2) Identify and evaluate the hazards of permit spaces before employees

enter them.” 29 C.F.R. § 1910.146(d)(2). Substantial evidence supports the

Board’s finding that Insituform violated this standard.

      The record supports that Insituform did not perform air monitoring as

required under this standard and by Insituform’s safety manual. Unsafe

atmospheric conditions are known hazards of sewer work. John Marich,

Insituform’s area vice president, testified when he went to retrieve the air

monitor the day after the accident, the air monitor was not in use.
                                     20

Additionally, the crew leader stated he did not “mess with air monitoring,”

that was for the crew to do.      Insituform’s safety manual requires air

monitoring before entry into a permit-required confined space.

      c. Citation two, item three. The Board found Insituform committed a

willful violation by not implementing the means, procedures, and practices

necessary for safe permit space entry operation when it did not ventilate the

space to eliminate hazards and did not verify the conditions in the space

were acceptable for entry, violating 29 C.F.R. section 1910.146(d)(3). This

standard states:

      (d) Under the permit space program required by paragraph
      (c)(4) of this section, the employer shall:

      ...

      (3) Develop and implement the means, procedures, and
      practices necessary for safe permit space entry operations,
      including, but not limited to, the following:

      (i) Specifying acceptable entry conditions;

      (ii) Providing each authorized entrant or that employee’s
      authorized representative with the opportunity to observe any
      monitoring or testing of permit spaces;

      (iii) Isolating the permit space;

      (iv) Purging, inerting, flushing, or ventilating the permit space
      as necessary to eliminate or control atmospheric hazards;

      (v) Providing pedestrian, vehicle, or other barriers as necessary
      to protect entrants from external hazards; and

      (vi) Verifying that conditions in the permit space are
      acceptable for entry throughout the duration of an authorized
      entry.

29 C.F.R. § 1910.146(d)(3). Substantial evidence supports the Board’s

finding that Insituform violated this standard.

      The record supports that on the day of the accident the sucker fan

and blower were not used to ventilate the area. Johnson and Walkenhorst
                                     21

testified on the day of the accident the jetter (a piece of ventilating

machinery) also was not used. Bull testified on the day of the accident the

air compressor would not start. No air monitoring was done on the day of

the accident. On other workdays, air monitoring was done intermittently at

best.

        d. Citation two, item four. The Board found Insituform committed a

willful violation because it failed to provide equipment to test and monitor

the atmospheric conditions and ensure that its employees used these

devices, violating 29 C.F.R. section 1910.146(d)(4)(i). This standard states:

        (d) Under the permit space program required by paragraph
        (c)(4) of this section, the employer shall:

        ...

        (4) Provide the following equipment (specified in paragraphs
        (d)(4)(i) through (d)(4)(ix) of this section) at no cost to
        employees, maintain that equipment properly, and ensure that
        employees use that equipment properly:

        (i) Testing and monitoring equipment needed to comply with
        paragraph (d)(5) of this section.

29 C.F.R. § 1910.146(d)(4)(i). Substantial evidence supports the Board’s

finding that Insituform violated this standard.
        Insituform employees worked in the permit-required confined space

without the equipment necessary to monitor the atmospheric conditions.

Employees testified they did not monitor the air every day.        Although

trained on air monitoring, a worker stated it “wasn’t like [air monitoring

was] demanded to be done every time.” Coffey, Walkenhorst, and Broz all

testified there was no air monitoring done on the day of the accident, and

indicated on other workdays, air monitoring was done intermittently at best.

VanBaale testified during the rescue he did not observe any air monitoring

devices. Bull admitted on the day of the accident no air monitoring was
                                     22

done. Insituform’s safety manual requires it to provide its employees with

equipment to test and monitor the atmospheric conditions.

      e. Citation two, item five. The Board found Insituform committed a

willful violation because it failed to provide ventilating equipment needed to

obtain acceptable entry conditions and ensure that its employees used the

equipment, violating 29 C.F.R. section 1910.146(d)(4)(ii). This standard

states:

      (d) Under the permit space program required by paragraph
      (c)(4) of this section, the employer shall:

      ...

      (4) Provide the following equipment (specified in paragraphs
      (d)(4)(i) through (d)(4)(ix) of this section) at no cost to
      employees, maintain that equipment properly, and ensure that
      employees use that equipment properly:

      ...

      (ii) Ventilating equipment needed to obtain acceptable entry
      conditions.

29 C.F.R. § 1910.146(d)(4)(ii). Substantial evidence supports the Board’s

finding that Insituform violated this standard.

      As previously mentioned, on the day of the accident neither the

sucker fan, the blower, nor the jetter were used to ventilate the area. Bull

testified on the day of the accident the air compressor would not start.

Ensuring that its employees used the ventilating equipment needed to

obtain acceptable entry conditions, as required by this standard, is also a

procedure required by Insituform’s safety manual.
      f. Citation two, item six. The Board found Insituform committed a

willful violation because it failed to provide personal protective equipment,

such as air or self-contained breathing apparatus and ensure that its
                                      23

employees    used    the    equipment,      violating   29   C.F.R.   section

1910.146(d)(4)(iv). This standard states:

      (d) Under the permit space program required by paragraph
      (c)(4) of this section, the employer shall:

      ...

      (4) Provide the following equipment (specified in paragraphs
      (d)(4)(i) through (d)(4)(ix) of this section) at no cost to
      employees, maintain that equipment properly, and ensure that
      employees use that equipment properly:

      ...

      (iv) Personal protective equipment insofar as feasible
      engineering and work practice controls do not adequately
      protect employees.

29 C.F.R. § 1910.126(d)(4)(iv). Substantial evidence supports the Board’s

finding that Insituform violated this standard.

      Five Insituform employees testified they were not wearing respirators

on the day of the accident and many of those employees indicated they

never wore respirators on the job site. The crew leader testified he did not

believe it was his responsibility to ensure that his workers were wearing

their respirators. Further, two workers on the site failed Insituform’s tests

on respirator usage. The record indicates either this was not communicated

to the supervisors at the job site or if the job site supervisor inquired, he

ignored the workers’ failure of the respirator tests and allowed them to work

regardless of the workers’ failure.

      g. Citation two, item seven. The Board found Insituform committed a

willful violation because it failed to provide equipment, such as ladders,

needed for safe ingress and egress by authorized entrants, violating 29

C.F.R. section 1910.146(d)(4)(vii). This standard states:

      (d) Under the permit space program required by paragraph
      (c)(4) of this section, the employer shall:
                                     24
      ...

      (4) Provide the following equipment (specified in paragraphs
      (d)(4)(i) through (d)(4)(ix) of this section) at no cost to
      employees, maintain that equipment properly, and ensure that
      employees use that equipment properly:

      ...

      (vii) Equipment, such as ladders, needed for safe ingress and
      egress by authorized entrants.

29 C.F.R. § 1910.146(d)(4)(vii). Substantial evidence supports the Board’s

finding that Insituform violated this standard.
      Johnson testified on the day of the accident he “leaped from the

concrete platform into the water” of the sewer. Coffey testified the ladder

leading to the sewer did not reach the ground and in order to reach the floor

of the sewer a worker had to jump from the ladder. VanBaale described the

distance from the ladder to the ground as between six and seven feet.

Walkenhorst recalled in order to get back onto the ladder you “had to prop

your hand up on the lid and just hoist yourself up.”        He recalled the

distance between the sewer floor and the ladder, the distance a worker had

to hoist himself up, as five feet. Another employee also testified the ladder

did not reach the ground. Insituform’s safety manual specifically required
ladders or other needed equipment to allow for “ingress and/or egress.”

      h. Citation two, item eight. The Board found Insituform committed a

willful violation by allowing employees to work in the sewer without

continuously monitoring the atmosphere and performing pre-entry testing,

violating 29 C.F.R. section 1910.146(d)(5)(i). This standard states:

      (d) Under the permit space program required by paragraph
      (c)(4) of this section, the employer shall:

      ...

      (5) Evaluate permit space conditions as follows when entry
      operations are conducted:
                                      25
      (i) Test conditions in the permit space to determine if
      acceptable entry conditions exist before entry is authorized to
      begin, except that, if isolation of the space is infeasible because
      the space is large or is part of a continuous system (such as a
      sewer), pre-entry testing shall be performed to the extent
      feasible before entry is authorized and, if entry is authorized,
      entry conditions shall be continuously monitored in the areas
      where authorized entrants are working.

29 C.F.R. § 1910.146(d)(5)(i). Substantial evidence supports the Board’s

finding that Insituform violated this standard.

      As previously noted, Johnson and Coffey testified on the day of the

accident there was no air monitor on site. The crew leader stated he did not

“mess with air monitoring” because that was for the crew to do. Insituform

workers regularly entered the sewer without air monitoring.          Even the

foreman had the misunderstanding that if the sewer was plugged, there was

no need to worry about chemicals in the sewer air. Insituform’s safety

manual specifically requires air monitoring before entry into a confined

space.
      i. Citation two, item ten. The Board found Insituform committed a

willful violation because it failed to identify and designate persons with

proper training to perform safety monitoring, violating 29 C.F.R. section
1910.146(d)(8). This standard states:

      (d) Under the permit space program required by paragraph
      (c)(4) of this section, the employer shall:

      ...

      (8) Designate the persons who are to have active roles (as, for
      example, authorized entrants, attendants, entry supervisors, or
      persons who test or monitor the atmosphere in a permit space)
      in entry operations, identify the duties of each such employee,
      and provide each such employee with the training required by
      paragraph (g) of this section.

29 C.F.R. § 1910.146(d)(8). Substantial evidence supports the Board’s

finding that Insituform violated this standard.
                                     26

      Training provided to Insituform’s supervisors and employees,

regarding entry, testing and monitoring, ventilating, and standby rescue

was not effective. A chain of command is provided by Insituform’s safety

manual. However, the workers at the sewer project did not follow or were

not aware of this chain of command. As mentioned earlier, Bull could not

even identify Insituform’s safety manual. Additionally, Insituform never

provided those in supervisory positions, such as Broz, training to know or

understand their duties or the chain of command structure.

      j. Citation two, item eleven. The Board found Insituform committed a

willful violation because its employees were allowed to enter and work in the

sewer without the protection provided by implementing a system for the

preparation, issuance, use, and cancellation of the required entry permits,

violating 29 C.F.R. section 1910.146(d)(10). This standard states:

      (d) Under the permit space program required by paragraph
      (c)(4) of this section, the employer shall:

      ...

      (10) Develop and implement a system for the preparation,
      issuance, use, and cancellation of entry permits as required by
      this section.

29 C.F.R. § 1910.146(d)(10). Substantial evidence supports the Board’s

finding that Insituform violated this standard.

      Insituform exposed its employees and supervisors to hazards that

would have been identified by the implementation of an entry permit

system. Even though Insituform employees entered the sewer almost every

day, confined space permits were only used sporadically. During the three-

month period Insituform employees worked on the sewer, only two entry

permits can be accounted for and were entered into evidence. Walkenhorst

testified he was never taught when to use the confined space entry permit.
                                      27

Johnson testified he knew a confined space permit was required to enter the

sewer, however, he only recalled permits being filled out sporadically.

Coffey similarly testified he knew of the permit system, but the permits were

rarely filled out. He recalls only filling out one permit, even though he

entered the sewer nearly every day.        Insituform’s safety manual had

procedures to implement a permit system to provide the necessary

protection to employees who entered the sewer.

      4. Does substantial evidence support that the violations found by the

Board and affirmed by this court in citation two are willful violations? The

Code does not contain a definition of a willful violation.       However, in

creating a civil penalty for a willful violation, the Code provides:

      Any employer who willfully or repeatedly violates the
      requirements of section 88.4, any standard, rule, or order
      adopted or issued pursuant to section 88.5, or rules adopted
      pursuant to this chapter, may be assessed a civil penalty of not
      more than seventy thousand dollars for each violation, but not
      less than five thousand dollars for each willful violation.

Iowa Code § 88.14(1). To determine what constitutes a willful violation, we

must interpret section 88.14(1).
      The interpretation of a statute is always a matter of law for this court.

City of Marion v. Iowa Dep’t of Revenue & Fin., 643 N.W.2d 205, 206 (Iowa

2002). Nevertheless, we are required to give appropriate deference to the

agency’s interpretation in certain situations.     Iowa Code § 17A.19(11).

Although the legislature gave the labor commissioner the authority to

promulgate Iowa’s occupational safety and health standards under section

88.5, the legislature did not vest the interpretation of “willful” under the

penalty provision with the commissioner or the Board. Accordingly, we

apply a correction-of-errors-at-law standard of review in interpreting the

statute. Id. § 17A.19(10)(c).
                                      28

      A willful violation is committed by an “employer who willfully . . .

violates . . . any standard [or] rule . . . adopted or issued pursuant to

section 88.5.” Id. § 88.14(1). We have previously interpreted a willful

violation “exists when the violation is committed with intentional disregard

of, or plain indifference to, the requirements of the regulation.” IBP, Inc. v.

Iowa Employment Appeal Bd., 604 N.W.2d 307, 321 (Iowa 1999). More than

mere negligence on the part of the employer is required to support a willful

violation. Id. The difference between a serious and willful violation of a

workplace safety standard is analogous to the difference between negligence

and recklessness in tort law. Id. Our interpretation is consistent with other

courts interpreting the federal Occupational Safety and Health Act. See

Ensign-Bickford Co. v. Occupational Safety & Health Review Comm’n, 717

F.2d 1419, 1422 (D.C. Cir. 1983) (stating “[a]lthough the Act does not define

the term ‘willful,’ courts have unanimously held that a willful violation of

the Act constitutes ‘an act done voluntarily with either an intentional

disregard of, or plain indifference to, the Act’s requirements’ ” (citation

omitted)).

      Insituform asks us to require actual knowledge of a violation and

specific evidence of that knowledge in every case in order to prove

willfulness.   To do so would be inconsistent with our interpretation of

willful. Our interpretation requires an intentional disregard or a plain

indifference to the requirements of our IOSH standards.            Under our

interpretation, “a plain indifference” is an alternative to “intentional

disregard.” Furthermore, a plain indifference without direct evidence that

the employer knew of each individual violation allows the finder of fact to

infer willfulness from that evidence. A.E. Staley Mfg. Co. v. Sec’y of Labor,
                                     29

295 F.3d 1341, 1350-51 (D.C. Cir. 2002). Accordingly, we will not require

proof of knowledge to establish a violation was willful.

      Applying our interpretation of the willful standard, we find

substantial evidence supports a finding that Insituform’s ten violations in

citation two are willful violations. Insituform’s safety manual contains an

entire chapter on confined spaces. It specifically references work in sewers.

The manual has detailed instructions on how to comply with the general

industry permit-required confined spaces standards. The manual shows

Insituform not only knew the permit-required confined spaces standards

existed, but also that it knew of the standard’s requirements.

      In spite of this knowledge, Insituform consistently failed to comply

with these standards throughout the entire time it worked on the sewer

project. One of Insituform’s on-site supervisors testified he never saw the

safety manual. The evidence supports a finding that ventilation equipment,

air monitors, personal protection equipment, and a proper ladder were not

present or properly used throughout the time Insituform’s employees were

working on the sewer. Employees were consistently allowed to enter the

sewer without first testing the atmospheric conditions in the sewer and

without implementing a system for the preparation, issuance, use, and

cancellation of the required entry permits. The ten violations the Board

found to exist under citation two were not one-time violations due to

inadvertence. The record demonstrates Insituform made no effort to comply

with its safety manual and the ten standards it violated in citation two.

This total indifference allows the Board to infer willfulness from the

evidence. Id.

      Therefore, we affirm the Board’s decision finding that Insituform

committed ten willful violations under citation two.
                                       30

      D. Whether the district court erred in combining the civil penalties

assessed by the Board. In its order, the Board fined Insituform $4500 for

each serious violation and $70,000 for each willful violation. The order

assessed a total penalty of $733,750. The total penalty assessed in the

order does not add up to the total amount of the individual fines assessed

in the order. This discrepancy is due to the order stating the fine for the

serious violation in citation one, item three is $4500, while the body of the

opinion reinstates the penalty in the citation of $2250. For our purposes,

we will assume the fine for the serious violation in citation one, item three is

$2250.

      On appeal to the district court, the court combined the penalties for

separate violations and lowered the total penalty to $158,000. The district

court combined the penalties on the theory that some of the separate

violations were duplicate violations because each of the separate violations

could be cured by a single act of abatement.

      The Code provides for each willful violation the employer “may be

assessed a civil penalty of not more than seventy thousand dollars for each

violation, but not less than five thousand dollars.” Iowa Code § 88.14(1).

For serious violations, the Code provides an employer “shall be assessed a

civil penalty up to seven thousand dollars for each such violation.” Id.

§ 88.14(2). The legislature left the determination of the appropriate penalty

for willful and serious violations to the Board. Id § 88.7(a). Accordingly, we

will give appropriate deference to the Board’s assessment of a penalty and

reverse the Board’s decision if it is based on an irrational, illogical, or wholly

unjustifiable application of law to the facts. Id. §§ 17A.19(10)(m), (11)(c).

      The penalty provisions of the federal Occupational Safety and Health

Act for willful and serious violations contain the same language as the Iowa
                                     31

penalty provisions.    Compare 29 U.S.C. § 666(a), (b), with Iowa Code

§ 88.14(1), (2). An early case decided by the federal occupational safety and

health review commission held when separate violations can be cured by a

single abatement, only one penalty should be assessed for the violations.

Sec’y of Labor v. Stimson Contracting Co., 5 O.S.H. Cas. (BNA) 1176, 1178

(Mar. 28, 1977).    A subsequent federal occupational safety and health

review commission decision overruled Stimson. Sec’y of Labor v. H.H. Hall

Constr. Co., 10 O.S.H. Cas. (BNA) 1042, 1046 (Oct. 7, 1981). In overruling

Stimson the commission stated:

      We have reconsidered Stimson and overrule it to the extent that
      it requires the Commission to vacate a citation or an item of a
      citation on the grounds that one violation is included within
      another cited violation. Although a worksite condition may
      violate more than one standard, section 5(a)(2) of the Act
      requires an employer to comply with all standards applicable to
      a hazardous condition even though the abatement
      requirements of two applicable standards may be satisfied by
      compliance with the more comprehensive standard. Thus,
      there is no unfair burden imposed on an employer when the
      same or closely related conditions are the subject of more than
      one citation item and a single action may bring an employer
      into compliance with the cited standards. However, the
      Commission has wide discretion in the assessment of penalties
      for distinct but potentially overlapping violations and it is
      appropriate to assess a single penalty for overlapping violations
      as the Commission has done in the past. Despite the fact that
      the violations alleged in this case, operation of heavy
      equipment near an excavation and improper support of trench
      walls, result in the same general hazard—collapse or cave-in—
      the conditions giving rise to the violations are separate and
      distinct. Accordingly, we conclude that Hall’s simultaneous
      noncompliance with two standards is not necessarily
      duplicative.

Id. (internal citations omitted).

      The federal courts have embraced this concept and recognized it is

discretionary on the commission as to whether to group multiple violations

and assess a single penalty. Dakota Underground, Inc. v. Sec’y of Labor, 200
                                      32

F.3d 564, 569 (8th Cir. 2000). We agree with the federal courts that the

Board has wide discretion in the assessment of penalties for distinct but

potentially overlapping violations of the standards.
      Under our standard of review, we cannot say the Board’s failure to
combine the penalties is an irrational, illogical, or wholly unjustifiable
application of law to the facts. The record clearly establishes Insituform
violated each standard as alleged by the commissioner. The Board has a
right to assess a penalty for each violation to deter conduct, to protect the
public from violations, and to punish the violator for its actions. Under
these circumstances, we will not disturb the assessment of the civil
penalties by the Board.
      IV. Disposition.
      Because the general industry permit-required confined spaces
standards apply to the work being done by Insituform’s employees, the
application of these standards is constitutional, substantial evidence
supports the Board’s decision, and the Board’s assessment of the civil
penalties was not an irrational, illogical, or wholly unjustifiable application
of law to the facts, we vacate the decision of the court of appeals, reverse
the judgment of the district court, and remand the case to the district court
to enter an order affirming the decision of the Board.
      DECISION OF COURT OF APPEALS VACATED; DISTRICT COURT
JUDGMENT REVERSED AND CASE REMANDED.
      All justices concur except Hecht and Appel, JJ., who take no part.
