1

Filed 9/25/23 Granite Construction Co. v. Occupational Safety and Health Appeals Bd. CA3

NOT TO BE PUBLISHED

California Rules of Court, rule 8.1115(a), prohibits courts and parties from citing or relying on opinions not certified for 

publication or ordered published, except as specified by rule 8.1115(b). This opinion has not been certified for publication

or ordered published for purposes of rule 8.1115.

IN THE COURT OF APPEAL OF THE STATE OF CALIFORNIA

THIRD APPELLATE DISTRICT

(Sacramento)

----

GRANITE CONSTRUCTION COMPANY, 

GRANITE INDUSTRIAL, INC.,

Plaintiff and Appellant,

v.

OCCUPATIONAL SAFETY AND HEALTH 

APPEALS BOARD,

Defendant and Respondent;

DEPARTMENT OF INDUSTRIAL RELATIONS, 

DIVISION OF OCCUPATIONAL SAFETY AND 

HEALTH,

Real Party in Interest and Respondent.

C096704

(Super. Ct. No. 34-2021-

80003634-CU-WM-GDS)

The Department of Industrial Relations, Division of Occupational Safety and 

Health (the Division) is a state agency authorized to issue citations to employers for 

workplace safety violations. In this case, it issued a citation to Granite Construction 
2

Company/Granite Industrial, Inc. (Granite Construction) for allegedly violating three 

regulations relevant here. It alleged Granite Construction violated one regulation because 

it required its employees to wear masks without first providing a medical evaluation to 

determine their fitness to wear them. And it alleged the company violated two other 

regulations because it exposed its employees to dust containing a harmful fungus—

namely, Coccidioides, the fungus that causes Valley fever—and failed to implement 

adequate measures to limit this exposure.

After Granite Construction disputed these allegations, an administrative law judge 

(ALJ) rejected the Division’s claims. The ALJ reasoned that no credible evidence 

showed that Granite Construction required its employees to wear masks and no reliable 

evidence showed that Coccidioides was present at the worksite. But after the Division 

petitioned for reconsideration, the Occupational Safety and Health Appeals Board (the 

Board) reversed on these issues and ruled for the Division. The trial court later denied 

Granite Construction’s petition for writ of administrative mandate seeking to set aside the 

Board’s decision. 

On appeal from the trial court, we reverse. We agree with Granite Construction’s

claim that insufficient evidence shows its employees were exposed to Coccidioides. But 

we reject its additional claim that it allowed (rather than required) its employees to wear 

masks, finding sufficient evidence supports the Board’s contrary ruling on this point. We 

will direct the trial court to enter a new judgment granting Granite Construction’s petition 

in part.

BACKGROUND

I

Factual Background

Much of the information about Valley fever in the record comes from government 

publications. One example is a Department of Industrial Relations webpage on Valley 

fever. According to the webpage, Valley fever is a potentially fatal disease caused by the 
3

fungus Coccidioides.

1

 The webpage states that Coccidioides lives in the top two to 12 

inches of soil in many parts of the state and can become airborne (and cause illness to 

those exposed) when this soil is disturbed. It adds that “[w]hile the fungal spores are 

more likely to be present in the soils of the Central Valley, they may also be present in 

other areas of California.” A map included in the webpage shows eight counties with 

annual Valley fever rates over 10 per 100,000 residents and many more with rates 

between 1 and 10 per 100,000 residents. Those with higher rates are Fresno, Kern, 

Kings, Madera, Merced, San Luis Obispo, Tulare, and, most relevant here, Monterey. A 

separate publication, from the Centers for Disease Control and Prevention (CDC), 

describes Coccidioides as “endemic in the southwestern United States, including 

California.”

The California Flats Solar Project is a large solar power plant built on part of a 

former cattle ranch in the southeastern corner of Monterey County. Before the project’s 

installation, and as a condition of project approval, the Monterey County Planning 

Department required the project applicant to take several measures intended to prevent 

the potential spread of Valley fever. These measures included requiring the project 

applicant to prepare a Valley fever management plan that, among other things, would 

have specific measures to reduce the potential for exposure to Valley fever; to implement 

additional dust suppression measures under certain windy or hot conditions; and to 

develop an educational handout about Valley fever for on-site workers and nearby 

residents. The Monterey County Planning Department also required the primary project 

1 The webpage states that Valley fever is caused by the fungus Coccidioides immitis, 

though other sources say Valley fever is actually caused by both Coccidioides immitis

and Coccidioides posadasii, with the former being the primary pathogen in California. 

We will use the term Coccidioides to refer to both Coccidioides immitis and Coccidioides 

posadasii.
4

contractor to prepare and implement a worker training program about Valley fever before 

any grading activity.

Consistent with these requirements, the owner of the project site created a Valley 

fever fact sheet, a Valley fever training program, and a Valley fever management plan for 

the project. The project general contractor, in turn, created a safety plan that identified 

Valley fever as a potential risk and described methods for mitigating this risk, noting, for 

instance, that workers can stop working if concerned about the potential presence of 

Coccidioides and request a filtering facepiece respirator. Granite Construction, one of the 

project subcontractors, also discussed Valley fever in safety instructions to its employees. 

It noted, for example, the potential risk of Valley fever and instructed its employees to 

“use mask if needed.” It also prepared a form (called a Job Hazard Analysis) that 

mentioned dust as a potential hazard from the use of a compactor and, as a control, 

instructed employees to keep material wet with an onsite water truck and, when dust is 

present, “[a]pply N95 dust mask”—a mask designed to block at least 95 percent of very 

small (0.3 micron) particles. It further mentioned dust as a potential hazard from 

backfilling and, as a control, instructed employees to keep distance to avoid dust from 

backfilling, apply water with an onsite water truck, and “[u]se N95 dust mask if 

necessary.” According to two of Granite Construction’s employees (Kayne Goff and 

Omar Cervantes), moreover, Granite Construction directed its employees to wear N95 

masks when it was dusty.

In May 2017, the Division began an inspection of the project worksite, which 

ultimately centered on the potential exposure of Granite Construction’s employees to 

Coccidioides. During their site visits, Division staff did not wear respiratory protection

to prevent their own potential exposure to Coccidioides. Nor did they test the site for 

Coccidioides, though staff assumed that tests were available to determine the presence of 

the fungus. No evidence in the record shows that any Granite Construction employee 
5

contracted Valley fever. Nor does any testimony show that any person who visited the 

worksite contracted Valley fever.

II

Procedural Background

Several months after the inspection, the Division issued a citation to Granite 

Construction. (See Lab. Code, § 6317 [discussing the Division’s authority to issue 

citations].) It alleged three violations relevant here. First, it alleged Granite Construction 

required its employees to wear respirators without first providing a medical evaluation to 

determine their fitness to wear a respirator, in violation of California Code of 

Regulations, title 8, section 5144, subdivision (e)(1) (section 5144(e)(1)).2 Second, it 

alleged the company failed to implement proper procedures to prevent exposure to 

Coccidioides during dust-generating activities and while working in dusty, windy 

environments, in violation of section 1509, subdivision (a). And third, it alleged the 

company failed to require its employees to wear respirators “when effective engineering 

controls were not feasible, or while they were being instituted, to protect against exposure 

to harmful dust contaminated with coccidioides fungal (Valley Fever) spores during . . . 

dust-generating activities and while working in dusty windy environments,” in violation 

of section 5144, subdivision (a)(1) (section 5144(a)(1)).

Granite Construction disputed these allegations, and, following briefing and a 

hearing, an ALJ rejected the Division’s claims. (See Lab. Code, § 6600 et seq. 

[describing the administrative process for appealing a Division citation].) Rejecting the 

alleged violation of section 5144(e)(1), the ALJ found no credible evidence that Granite 

Construction required its employees to wear respirators, finding respirator use to instead 

be voluntary. And rejecting the alleged violations of sections 1509 and 5144(a)(1), the 

2 Further undesignated regulation references are to title 8 of the California Code of 

Regulations.
6

ALJ found no reliable evidence that Granite Construction exposed its employees to 

Coccidioides, explaining that although the fungus is present in parts of Monterey County, 

no reliable evidence showed it was present at the worksite here. The ALJ added that no 

one contracted Valley fever during the six months before the Division’s citations, no one 

sampled for Coccidioides at the worksite, and no Division employee even showed a 

personal concern for the fungus during the inspections, as evidenced by their not wearing 

respirators. The ALJ concluded that the presence of Coccidioides could not merely be 

assumed. And even if Coccidioides was assumed to be present, the ALJ found the 

Division’s allegations would still fall short. That was because Granite Construction took 

adequate measures to prevent exposure to Coccidioides and the Division did not prove, in 

any event, that any respirator would have been effective to filter out Coccidioides.

After the Division petitioned for reconsideration, the Board reversed the ALJ’s 

decision on these issues. Starting with section 5144(a)(1), the Board found Granite 

Construction exposed its employees to harmful dust (here, dust contaminated with 

Coccidioides), failed to use accepted engineering control measures as far as feasible to 

prevent exposure, and failed to require respirators when appropriate, instead “deci[ding] 

to leave virtually unlimited discretion regarding mask usage to employees.” The Board 

concluded that Granite Construction violated section 5144(a)(1) as a result. It also found 

Granite Construction violated section 1509, subdivision (a) for similar reasons, reasoning 

that it exposed its employees to Coccidioides and failed to impose adequate measures to 

protect its employees. Lastly, it found the company violated section 5144(e)(1). 

Appearing to backtrack from its finding that Granite Construction “deci[ded] to leave 

virtually unlimited discretion regarding mask usage to employees,” the Board now found 

Granite Construction “had a rule requiring employees to wear or use the masks under 

dusty or windy conditions.” And because Granite Construction never evaluated its 

employees’ fitness to wear these required masks, the Board found it consequently 

violated section 5144(e)(1).
7

Granite Construction afterward filed a petition for writ of administrative mandate 

in the trial court, seeking to have the court set aside the Board’s decision. But the court 

found none of Granite Construction’s arguments persuasive and denied the petition.

Granite Construction timely appealed.

DISCUSSION

I

Scope of Review

The scope of our review, like the trial court’s, is limited. (See Lusardi 

Construction Co. v. California Occupational Safety & Health Appeals Bd. (1991) 1 

Cal.App.4th 639, 643 [“Our function on appeal is the same as that of the trial court in 

ruling on the petition for the writ”].) Per Labor Code section 6629, our review “shall not 

be extended further than to determine, based upon the entire record which shall be 

certified by the appeals board, whether: [¶] (a) The appeals board acted without or in 

excess of its powers. [¶] (b) The order or decision was procured by fraud. [¶] (c) The 

order or decision was unreasonable. [¶] (d) The order or decision was not supported by 

substantial evidence. [¶] (e) If findings of fact are made, such findings of fact support 

the order or decision under review.”

In evaluating whether the Board’s decision was supported by substantial evidence, 

“[w]e view the evidence in a light most favorable to the Board’s decision, drawing all 

reasonable inferences and resolving all conflicts in the evidence in favor of the decision.” 

(Teichert Construction v. California Occupational Safety & Health Appeals Bd. (2006) 

140 Cal.App.4th 883, 888.) Under this standard, we will uphold the Board’s decision if 

the record contains sufficient evidence that is reasonable, credible, and of solid value to 

allow a reasonable person to reach the challenged decision. (People v. Barnwell (2007) 

41 Cal.4th 1038, 1052 [describing substantial evidence standard].) 
8

II

Section 5144(a)(1)

Granite Construction first challenges the Board’s finding that it violated section 

5144(a)(1)—a finding, again, that was largely premised on the Board’s conclusion that 

the company exposed its employees to Coccidioides. Granite Construction contends the 

Board lacks authority to regulate exposure to Coccidioides and, even if it has this 

authority, it could not find a violation of section 5144(a)(1) on the facts of this case, in 

part because no evidence showed Coccidioides was present at the worksite here. We 

agree with its latter argument.

Section 5144(a)(1) states: “In the control of those occupational diseases caused 

by breathing air contaminated with harmful dusts, fogs, fumes, mists, gases, smokes, 

sprays, or vapors, the primary objective shall be to prevent atmospheric contamination. 

This shall be accomplished as far as feasible by accepted engineering control measures 

(for example, enclosure or confinement of the operation, general and local ventilation, 

and substitution of less toxic materials). When effective engineering controls are not 

feasible, or while they are being instituted, appropriate respirators shall be used pursuant 

to this section.” 

The Board has interpreted section 5144(a)(1) to require the Division to show four 

things to establish a violation: (1) the Division’s citation concerned an atmospheric 

contaminant covered under section 5144(a)(1) (e.g., harmful dusts), (2) one or more of 

the employer’s employees were exposed to that contaminant, (3) the employer failed to 

use accepted engineering control measures as far as feasible to prevent atmospheric 

contamination, and (4) when effective engineering controls were not feasible to prevent 

atmospheric contamination, or while being instituted, appropriate respirators were not 

used. Because no party disputes this interpretation, we accept for purposes here that 

these are the applicable elements to establish a violation of section 5144(a)(1).
9

Our focus here is on the second of these elements—that is, the one concerning 

employee exposure to an atmospheric contaminant covered under section 5144(a)(1). 

Over the years, the Board has discussed two competing standards for evaluating whether 

an employee has been exposed to an atmospheric contaminant within the meaning of this 

regulation. It established the first standard—the “harmful exposure” standard—decades 

ago. Under this standard, the Division must show “ ‘[a]n exposure to dusts, fumes, mists, 

vapors, or gases . . . [o]f such a nature by inhalation as to result in, or have a probability 

to result in, injury, illness, disease, impairment, or loss of function.’ ” (Papich 

Construction Co., Inc. (Cal. OSHA, Mar. 26, 2021, No. 1236440) 2021 CA OSHA 

App.Bd. Lexis 23, *13, *18.) Evaluating an alleged harmful exposure in a 1978 decision, 

the Board found the Division could not establish a violation unless it showed actual 

exposure to some harmful dust, fume, mist, vapor, or gas. (Interior Contractors (Cal. 

OSHA, Apr. 7, 1978, No. 75-R3D1-1214) 1978 CA OSHA App.Bd. Lexis 40.) Although 

in that case, the Division argued workers had been exposed to dust containing asbestos, 

the Board found “there [wa]s a total absence of any evidence that the workers were 

exposed to any specific level of asbestos fibers, only an assumption that they were 

exposed to some unknown level of dust that likely contained asbestos.” (Id. at pp. *2-

*3.) “Such evidence,” the Board concluded, “is not sufficient to sustain an alleged 

violation of [section] 5144(a).” (Id. at p. *3.) 

The Board has since suggested that an alternative standard—the “zone of danger” 

standard—might be more appropriate in evaluating alleged violations of section 

5144(a)(1). (Papich Construction Co., Inc., supra, 2021 CA OSHA App.Bd. Lexis 23 at 

p. *13.) Under this alternative standard, the Division must show either “that the 

employees have been or are in the zone of danger” or “ ‘that it is reasonably predictable 

by operational necessity or otherwise, including inadvertence, that employees have been, 

are, or will be in the zone of danger.’ ” (Ibid.) The Board has generally applied this 

standard in contexts involving regulations other than section 5144. It first appears to 
10

have done so in 2003, finding an employer exposed its employees to a zone of danger 

when it had on its premises a torch and welding machine lacking required safety 

protections. (Benicia Foundry & Iron Works, Inc. (Cal. OSHA, Apr. 24, 2003, No. 00-

R2D2-2976 through 2984, 2986, 2987) 2003 CA OSHA App.Bd. Lexis 43, *59-*61.) 

Although the employer argued the Division needed to show that its employees actually 

used this machine, the Board found persuasive the rationale that it should be able to 

require the abatement of dangerous conditions “ ‘upon a showing that a condition exists 

at a worksite in violation of a safety standard and the hazard posed by the violation is 

accessible to employees . . . or that the hazard otherwise may pose dangers to employees 

that may be described in functional rather than spatial terms.’ ” (Id. at pp. *54-*57.) 

To date, the Division has yet to decide which of these two standards—the 

“harmful exposure” standard or the “zone of danger” standard—is the appropriate one in 

cases involving alleged violations of section 5144(a)(1). It has instead, in each case it has 

considered these standards, found it unnecessary to decide between the two standards 

because it concluded that both favor the same result. (See Papich Construction Co., Inc.,

supra, 2021 CA OSHA App.Bd. Lexis 23 at pp. *13.) In its decision here, for example, 

the Board noted that the “harmful exposure” standard is the one it has applied in past 

decisions involving section 5144(a)(1). But at the same time, it noted it might have 

reason to “overrule” this approach and apply the “zone of danger” standard—which it 

characterized as its “typical exposure analysis.” In the end, though, the Board wrote that 

it “need not resolve the issue at this juncture as the issue is not dispositive and employee 

exposure exists under either of the mentioned standards.” 

We too need not resolve here which of these standards, if any, is best. We instead 

accept for purposes here that one of these standards applies—which no party disputes—

and conclude that under either standard, the Board’s finding that employees were 

exposed to dusts containing Coccidioides lacks evidentiary support. In other words, no 

matter the standard used, and no matter how generously we view the evidence, the 
11

evidence does not support the Board’s finding that the Division established the second 

element for the alleged violation of section 5144(a)(1). (See Lab. Code, § 6629, subd. 

(d).)

We start with the “harmful exposure” standard. The Board concluded this 

standard was satisfied here because “inhalation of the cocci spores will result in, or has a 

probability to result in, injury, illness, disease, impairment, or loss of function.” But 

under the relevant standard, the Division had to show more than that Coccidioides can be 

harmful if inhaled; it also had to show that Granite Construction’s employees were 

exposed to this fungus. After all, the “harmful exposure” standard requires “ ‘[a]n 

exposure’ ” to a harmful substance, not simply an evaluation of a harmful substance that 

may or may not have been present. (Papich Construction Co., Inc., supra, 2021 CA 

OSHA App.Bd. Lexis 23 at p. *18.) And as the ALJ noted here (before the Board 

reversed his decision), the record is void of evidence showing any employee was exposed 

to “even one cocci spore during the six months prior to issuance of the citation.”

We turn next to the “zone of danger” standard. In its decision, the Board 

suggested the worksite here was a “zone of danger” because Coccidioides exists and is 

endemic in Monterey County, Monterey County has taken steps to reduce the spread of 

Valley fever through mitigation measures covering the worksite, and Granite 

Construction itself had informed its employees about Valley fever and described methods 

for limiting dust exposure. But those considerations only show that the worksite was a 

potential zone of danger, not an actual zone of danger. And according to the Board’s 

own description of the “zone of danger” standard, the standard requires an actual zone of 

danger. In the Board’s words, the “zone of danger is that area surrounding the violative 

condition that presents the danger to employees that the standard is intended to prevent,”

not the area that might present a danger to employees. (Benicia Foundry & Iron Works, 

Inc., supra, 2003 CA OSHA App.Bd. Lexis 43 at p. *54, italics added.) 
12

Here, however, nothing we have found in the record shows that any part of the 

worksite “present[ed] [a] danger to employees.” The CDC, to be sure, has said 

Coccidioides is endemic in California. But that does not mean that the fungus is present 

everywhere in the state (or for that matter, everywhere in Monterey County)—which 

even Division staff conceded. The Department of Industrial Relations, moreover, has 

indicated that Monterey County and seven other counties have relatively high rates of 

Valley fever, with rates over 10 per 100,000 people. But that does not mean that 

Coccidioides was present (or even likely present) at the worksite here. Nor does it even 

show a meaningful probability that the fungus was present. And although Monterey 

County and even Granite Construction demonstrated concerns about Valley fever and 

took steps to limit potential exposure, that too does not show that Coccidioides was 

actually present. All this evidence instead only shows, with no degree of certainty, that 

the worksite might have presented a danger to employees because Coccidioides might 

have been present in the soil. That, however, is insufficient to support the Board’s 

finding that the worksite was in fact a zone of danger. (People v. Davis (2013) 57 Cal.4th 

353, 360 [“ ‘ “A finding of fact must be an inference drawn from evidence rather than . . . 

a mere speculation as to probabilities without evidence” ’ ”].) Neither of the Board’s 

offered standards, then, favor its finding that “one or more of [Granite Construction’s] 

employees were exposed to harmful dusts”—which again, per the Board’s own 

interpretation, is one of the required elements to establish a violation of section 

5144(a)(1).

Nor are we persuaded to find differently by the Division’s and the Board’s 

arguments on appeal. Before turning to their arguments, however, we note what they do 

not argue. Neither the Board nor the Division argues that the Division’s showing 

satisfied the “harmful exposure” standard. They never even acknowledge Granite 

Construction’s argument concerning the Division’s failure to meet this standard, 

appearing to concede the issue. That in itself is arguably fatal to their position, for 
13

according to the Board in its decision here, the “harmful exposure” standard has yet to be 

overruled and so remains the applicable standard in cases involving section 5144(a)(1). 

(See also Papich Construction Co., Inc., supra, 2021 CA OSHA App.Bd. Lexis 23 at p. 

*13 [“the Board has historically held ‘harmful exposure’ is the actual required inquiry”].) 

But even setting that aside, we find the Board’s and the Division’s arguments—all 

of which concern the “zone of danger” standard—unpersuasive. The Board, to start, 

follows a similar approach it followed in the administrative proceedings in discussing the 

“zone of danger” standard. It argues the “worksite constitutes ‘a zone of danger’ ” 

because Coccidioides is endemic in Monterey County, “[e]veryone involved in the . . . 

project” acknowledged the risk of Valley fever, and dust-generating activities (like those 

Granite Construction performed) increase the likelihood of exposure to Coccidioides. 

Those considerations, as noted, show that the worksite was a potential zone of danger, 

with Coccidioides potentially present. But again, the relevant standard is not focused on 

exposure or access to a potential zone of danger; it is instead focused on a zone of danger 

in fact—and the evidence fails to establish the existence of such a zone here. Monterey 

County, as covered, might have relatively high rates of Valley fever. And regulatory 

agencies might, for that reason, have cause to encourage employers like Granite 

Construction to require their outdoor workers to wear masks as a preventive measure, 

even if the presence of Coccidioides is not confirmed. But that does not mean that the 

worksite here was a zone of danger because of the presence of Coccidioides—a fungus 

that we can, at most, only speculate was present. 

The Board next, taking a different approach, asserts Granite Construction forfeited 

its challenge to the sufficiency of the evidence. That is so, it argues, because Granite 

Construction provided only a one-sided account of the relevant facts. (See Rayii v. 

Gatica (2013) 218 Cal.App.4th 1402, 1408 [an appellant “who cites and discusses only 

evidence in [his or her] favor fails to demonstrate any error and waives the contention 

that the evidence is insufficient to support the judgment”].) But the Board never 
14

discusses the facts that Granite Construction allegedly failed to cover. It instead vaguely 

states that Granite Construction “cites minimal evidence, and only where that evidence 

might, out of context, support its position.” Unpersuaded by this showing, we reject the 

Board’s claim of forfeiture. 

The Division, in turn, argues its evidence satisfied the “zone of danger” standard 

and then says the “zone of danger here is exposure to cocci spores.” But the zone of 

danger is a physical place, not an experience. And to the extent the Division believes 

Granite Construction’s employees were exposed to Coccidioides, it cites nothing in the 

record to support this claim. Although, in its statement of facts, it claims “the health 

department found that there were confirmed cases of Valley fever from employees 

working at the jobsite,” it never backs up this claim. It instead cites an article discussing 

Valley fever at two solar power facilities in San Luis Obispo County, not Monterey 

County. And although the Division further asserts that the CDC confirmed seven cases 

of Valley fever “among workers constructing the California Flats Solar Project,” the 

article it cites never specifically or directly mentions the California Flats Solar Project but 

instead discusses an undisclosed solar farm in Monterey County. Nor, as far as we can 

find in our review of the transcript, did the Division ever present evidence showing the 

article concerned this project; it instead simply described it as “a CDC publication on a 

study of Valley Fever outbreak among workers constructing a solar power farm in 

Monterey County.” The Division may nonetheless speculate that Coccidioides was 

present at the worksite here, but speculation is not substantial evidence. (People v. Davis, 

supra, 57 Cal.4th at p. 360.) 

The Division also contends it is too difficult to test for the presence of 

Coccidioides and so suggests we must simply presume the fungus was present, with the 

burden then shifted on to Granite Construction to prove the negative—that Coccidioides

was not present. It adds that workplace safety laws should be construed broadly under 

our Supreme Court’s precedent. (See Carmona v. Division of Industrial Safety (1975) 13 
15

Cal.3d 303, 312 [work safety laws in the Labor Code should be construed broadly].) But 

it cites nothing to show that testing for Coccidioides is, as it claims, difficult; and after 

reviewing the record, we find that its own expert assumed that a test existed to test for the 

presence of Coccidioides in the soil. The Division, moreover, cites no authority creating 

an exception to the “harmful exposure” and “zone of danger” standards in these types of 

circumstances. Again, the “harmful exposure” standard requires “[a]n exposure,” not an 

exposure except when it is difficult to prove an exposure. And the “zone of danger” 

standard requires an area that presents a danger to employees, not an area that presents a 

danger except when it is difficult to prove the danger.

In sum, we find the Board’s conclusion that Granite Construction violated section 

5144(a)(1) was not supported by substantial evidence. Neither of the Board’s offered 

standards for evaluating employee exposure under section 5144(a)(1) are satisfied when a 

harmful contaminant is only, at most, speculatively present. Nor, considering section 

5144(a)(1)’s plain language, can we say that its requirements clearly apply in these types 

of circumstances. Perhaps in the future, the Board may adopt a broader interpretation of 

section 5144(a)(1) that involves neither the “zone of danger” standard nor the “harmful 

exposure” standard. (See Henning v. Industrial Welfare Com. (1988) 46 Cal.3d 1262, 

1269 [an agency generally may change its interpretation of a statute]; but see FCC v. Fox 

Television Stations, Inc. (2012) 567 U.S. 239, 253-254 [when an agency changes its 

interpretation, “regulated parties should know what is required of them so they may act 

accordingly” before the agency starts imposing penalties].) But that is not an issue before 

us today. And applying the Board’s existing standards for interpreting section 

5144(a)(1), we conclude that its finding that employees were exposed to dust containing 

Coccidioides lacks evidentiary support.3

3 Because we find the Board’s decision is not supported by substantial evidence, we need 

not address Granite Construction’s other arguments for challenging the finding that it 
16

III

Section 1509, subdivision (a)

Granite Construction also challenges the Board’s finding that it violated section 

1509, subdivision (a)—which was tied to the Board’s finding that it violated section 

5144(a)(1). We agree.

Section 1509, subdivision (a) states: “Every employer shall establish, implement 

and maintain an effective Injury and Illness Prevention Program in accordance with 

section 3203 of the General Industry Safety Orders.” Section 3203, in turn, as relevant 

here, states: “[E]very employer shall establish, implement and maintain an effective 

Injury and Illness Prevention Program (Program)” that, at a minimum, includes “methods 

and/or procedures for correcting unsafe or unhealthy conditions, work practices and work 

procedures in a timely manner based on the severity of the hazard: [¶] (A) When 

observed or discovered; and, [¶] (B) When an imminent hazard exists which cannot be 

immediately abated without endangering employee(s) and/or property, remove all 

exposed personnel from the area except those necessary to correct the existing 

condition.” (§ 3203, subd. (a)(6).) 

In its citation here, the Division alleged Granite Construction violated section 

1509, subdivision (a) because it did not implement proper practices to protect its 

employees from dust containing Coccidioides. The Board agreed, relying on its finding 

that “employees were exposed to hazards associated with Valley Fever.” As covered 

violated section 5144(a)(1). These include its arguments that (1) the Board has no 

authority to regulate exposure to Coccidioides; (2) the Board should have dismissed the 

Division’s citation because the company complied with a new statute requiring 

companies to provide Valley fever awareness training under certain circumstances; (3) 

Coccidioides is not an atmospheric contaminant within the meaning of section 

5144(a)(1), because a contaminant is a material that is foreign to the environment and 

Coccidioides is native to the environment; (4) it implemented sufficient controls to limit 

exposure to any harmful dust even without masks; and (5) even if it violated section 

5144(a)(1), the violation should not have been deemed a serious violation.
17

above, however, we conclude that the Board’s finding that “employees were exposed to 

hazards associated with Valley Fever” lacks evidentiary support. (See Lab. Code, § 

6629, subd. (d).)4

IV

Section 5144(e)(1)

Lastly, Granite Construction challenges the Board’s finding that it violated section 

5144(e)(1)—a provision that requires employers to “provide a medical evaluation to 

determine the employee’s ability to use a respirator, before the employee is . . . required 

to use the respirator in the workplace.” Granite Construction argues section 5144(e)(1) is 

inapplicable because it never required its employees to use masks. It then, challenging 

the Board’s contrary finding, asserts the Board wrongly credited the testimony of Goff 

after the ALJ found him not credible, says Goff’s and Cervantes’s poor memories weaken 

their credibility, and contends its employees signed paperwork showing that the masks it 

provided (i.e., the N95 masks) were for voluntary use only. 

We reject its argument. Even setting aside Goff’s testimony, we find the record 

contains sufficient evidence to show that Granite Construction required its employees to 

wear masks.5 Cervantes testified that he was a Granite Construction employee in 2017 

and worked at the California Flats Solar Project site. He also testified that Granite 

Construction required its employees to wear masks when it was dusty. That was not a 

suggestion or advice; it was a “rule.” Cervantes added that when supervisors saw 

employees without masks, they told them to put on their masks. Consistent with 

4 Having resolved Granite Construction’s claim on this ground, we need not address its 

additional argument that it implemented effective practices to prevent exposure to 

Coccidioides. Nor need we address its argument that even if it failed to do so, its 

violation should not have been found to be a serious violation.

5 We assume, for purposes here, that an N95 mask is a “respirator” within the meaning 

of section 5144(e)(1)—something that Granite Construction has not disputed.
18

Cervantes’s testimony, moreover, Granite Construction’s Job Hazard Analysis mentioned 

dust as a potential hazard for certain activities and instructed employees to “[a]pply N95 

dust mask if dust around work area is present” and “[u]se N95 dust mask if necessary.”

Considering this evidence, we find substantial evidence supports the Board’s 

finding that Granite Construction required its employees to wear masks—at least when it 

was perceived to be dusty. (People v. Barnwell, supra, 41 Cal.4th at p. 1052 [the 

testimony of a single witness can constitute substantial evidence].) Although Granite 

Construction, in a footnote, quotes the ALJ as saying that “Goff’s and Cervantes’ poor 

memories weaken their credibility,” it ultimately only discusses details allegedly showing 

Goff’s poor memory, with nothing showing the same for Cervantes. (See Jumaane v. 

City of Los Angeles (2015) 241 Cal.App.4th 1390, 1406 [courts “may disregard any 

claims when no reference [to the record] is furnished”]; see also Holden v. City of San 

Diego (2019) 43 Cal.App.5th 404, 419-420 [courts need not address arguments made in 

footnotes].) And although Granite Construction claims its employees signed paperwork 

showing that the masks provided were for voluntary use only, all it cites in support are 

two unsigned documents. It cites nothing showing that any employee signed these 

documents. And even if its employees had signed these documents, that would not 

necessarily be enough to counter Cervantes’s testimony, for “[e]ven when there is a 

significant amount of countervailing evidence, the testimony of a single witness that 

satisfies the [substantial evidence] standard is sufficient to uphold the finding.” 

(Barnwell, at p. 1052.) 
19

DISPOSITION

The judgment is reversed. The trial court is instructed to enter a new judgment 

partly granting Granite Construction’s petition, consistent with this opinion. Granite 

Construction is entitled to recover its costs on appeal. (Cal. Rules of Court, rule 

8.278(a).)

 /s/

BOULWARE EURIE, J.

We concur:

 /s/

RENNER, Acting P. J.

 /s/

KRAUSE, J.