(Slip Opinion)              OCTOBER TERM, 2013                                       1

                                       Syllabus

         NOTE: Where it is feasible, a syllabus (headnote) will be released, as is
       being done in connection with this case, at the time the opinion is issued.
       The syllabus constitutes no part of the opinion of the Court but has been
       prepared by the Reporter of Decisions for the convenience of the reader.
       See United States v. Detroit Timber & Lumber Co., 200 U. S. 321, 337.


SUPREME COURT OF THE UNITED STATES

                                       Syllabus

   SANDIFER ET AL. v. UNITED STATES STEEL CORP.

CERTIORARI TO THE UNITED STATES COURT OF APPEALS FOR
                THE SEVENTH CIRCUIT

  No. 12–417.      Argued November 4, 2013—Decided January 27, 2014
Petitioner Sandifer and others filed a putative collective action under
  the Fair Labor Standards Act of 1938, seeking backpay for time spent
  donning and doffing pieces of protective gear that they assert re-
  spondent United States Steel Corporation requires workers to wear
  because of hazards at its steel plants. U. S. Steel contends that this
  donning-and-doffing time, which would otherwise be compensable
  under the Act, is noncompensable under a provision of its collective-
  bargaining agreement with petitioners’ union. That provision’s valid-
  ity depends on 29 U. S. C. §203(o), which allows parties to collectively
  bargain over whether “time spent in changing clothes . . . at the be-
  ginning or end of each workday” must be compensated. The District
  Court granted U. S. Steel summary judgment in pertinent part, hold-
  ing that petitioners’ donning and doffing constituted “changing
  clothes” under §203(o). It also assumed that any time spent donning
  and doffing items that were not “clothes” was “de minimis” and hence
  noncompensable. The Seventh Circuit affirmed.
Held: The time petitioners spend donning and doffing their protective
 gear is not compensable by operation of §203(o). Pp. 3–15.
    (a) This Court initially construed compensability under the Fair
 Labor Standards Act expansively. See, e.g., Anderson v. Mt. Clemens
 Pottery Co., 328 U. S. 680. The Act was amended in 1949, however,
 to provide that the compensability of time spent “changing clothes or
 washing at the beginning or end of each workday” is a subject appro-
 priately committed to collective bargaining, §203(o). Whether peti-
 tioners’ donning and doffing qualifies as “changing clothes” depends
 on the meaning of that statutory phrase. Pp. 3–6.
    (b) The term “clothes,” which is otherwise undefined, is “interpret-
 ed as taking [its] ordinary, contemporary, common meaning.” Perrin
2            SANDIFER v. UNITED STATES STEEL CORP.

                                  Syllabus

    v. United States, 444 U. S. 37, 42. In dictionaries from the era of
    §203(o)’s enactment, “clothes” denotes items that are both designed
    and used to cover the body and are commonly regarded as articles of
    dress. Nothing in §203(o)’s text or context suggests anything other
    than this ordinary meaning. There is no basis for petitioners’ propo-
    sition that the unmodified term “clothes” somehow omits protective
    clothing. Section 203(o)’s exception applies only when the changing
    of clothes is “an integral and indispensable part of the principal activ-
    ities for which covered workmen are employed,” Steiner v. Mitchell,
    350 U. S. 247, 256, and thus otherwise compensable under the Act.
    See 29 U. S. C. §254(a). And protective gear is the only clothing that
    is integral and indispensable to the work of many occupations, such
    as butchers and longshoremen. Petitioners’ position is also incompat-
    ible with the historical context of §203(o)’s passage, contradicting
    contemporaneous Labor Department regulations and dictum in Stei-
    ner, see 350 U. S., at 248, 254–255. The interpretation adopted here
    leaves room for distinguishing between clothes and wearable items
    that are not clothes, such as some equipment and devices. The view
    of respondent and its amici that “clothes” encompasses the entire out-
    fit that one puts on to be ready for work is also devoid of any textual
    foundation. Pp. 6–10.
       (c) While the normal meaning of “changing clothes” connotes sub-
    stitution, “changing” also carried the meaning to “alter” at the time of
    §203(o)’s enactment. The broader statutory context makes plain that
    “time spent in changing clothes” includes time spent in altering
    dress. Whether one exchanges street clothes for work clothes or
    simply chooses to layer one over the other may be a matter of purely
    personal choice, and §203(o) should not be read to allow workers to
    opt into or out of its coverage at random or at will when another
    reading is textually permissible. Pp. 10–11.
       (d) Applying these principles here, it is evident that the donning
    and doffing in this case qualifies as “changing clothes” under §203(o).
    Of the 12 items at issue, only 3—safety glasses, earplugs, and a res-
    pirator—do not fit within the elaborated interpretation of “clothes.”
    Apparently concerned that federal judges would have to separate the
    minutes spent clothes-changing and washing from the minutes de-
    voted to other activities during the relevant period, some Courts of
    Appeals have invoked the doctrine de minimis non curat lex (the law
    does not take account of trifles). But that doctrine does not fit com-
    fortably within this statute, which is all about trifles. A more appro-
    priate way to proceed is for courts to ask whether the period at issue
    can, on the whole, be fairly characterized as “time spent in changing
    clothes or washing.” If an employee devotes the vast majority of that
    time to putting on and off equipment or other non-clothes items, the
                     Cite as: 571 U. S. ____ (2014)                     3

                                Syllabus

  entire period would not qualify as “time spent in changing clothes”
  under §203(o), even if some clothes items were also donned and
  doffed. But if the vast majority of the time is spent in donning and
  doffing “clothes” as defined here, the entire period qualifies, and the
  time spent putting on and off other items need not be subtracted.
  Here, the Seventh Circuit agreed with the District Court’s conclusion
  that the time spent donning and doffing safety glasses and earplugs
  was minimal. And this Court is disinclined to disturb the District
  Court’s additional factual finding, not addressed by the Seventh Cir-
  cuit, that the respirators were donned and doffed as needed during
  the normal workday and thus fell beyond §203(o)’s scope. Pp. 12–15.
678 F. 3d 590, affirmed.

  SCALIA, J., delivered the opinion of the Court, in which ROBERTS,
C. J., and KENNEDY, THOMAS, GINSBURG, BREYER, ALITO, and KAGAN,

JJ., joined, and in which SOTOMAYOR, J., joined except as to footnote 7. 

                         Cite as: 571 U. S. ____ (2014)                              1

                              Opinion of the Court

      NOTICE: This opinion is subject to formal revision before publication in the
      preliminary print of the United States Reports. Readers are requested to
      notify the Reporter of Decisions, Supreme Court of the United States, Wash-
      ington, D. C. 20543, of any typographical or other formal errors, in order
      that corrections may be made before the preliminary print goes to press.


SUPREME COURT OF THE UNITED STATES
                                    _________________

                                    No. 12–417
                                    _________________


CLIFTON SANDIFER, ET AL., PETITIONERS v. UNITED
         STATES STEEL CORPORATION
 ON WRIT OF CERTIORARI TO THE UNITED STATES COURT OF 

           APPEALS FOR THE SEVENTH CIRCUIT

                                [January 27, 2014]


  JUSTICE SCALIA delivered the opinion of the Court.*
  The question before us is the meaning of the phrase
“changing clothes” as it appears in the Fair Labor Stand-
ards Act of 1938, 52 Stat. 1060, as amended, 29 U. S. C.
§201 et seq. (2006 ed. and Supp. V).
              I. Facts and Procedural History
  Petitioner Clifton Sandifer, among others, filed suit
under the Fair Labor Standards Act against respondent
United States Steel Corporation in the District Court for
the Northern District of Indiana. The plaintiffs in this
putative collective action are a group of current or former
employees of respondent’s steelmaking facilities.1 As

——————
   * JUSTICE SOTOMAYOR joins this opinion except as to footnote 7.
   1 Petitioners filed this action under 29 U. S. C. §216(b), which estab-

lishes a cause of action that may be maintained “by any one or more
employees for and in behalf of himself or themselves and other employ-
ees similarly situated.” Pending resolution of the instant summary-
judgment dispute, a Magistrate Judge set aside a motion to certify the
suit as a collective action, see No. 2:07–CV–443 RM, 2009 WL 3430222,
*1, n. 1 (ND Ind., Oct. 15, 2009), but petitioners assert that their ranks
are about 800 strong.
2           SANDIFER v. UNITED STATES STEEL CORP.

                         Opinion of the Court

relevant here, they seek backpay for time spent donning
and doffing various pieces of protective gear. Petitioners
assert that respondent requires workers to wear all of the
items because of hazards regularly encountered in steel
plants.
   Petitioners point specifically to 12 of what they state are
the most common kinds of required protective gear: a
flame-retardant jacket, pair of pants, and hood; a hardhat;
a “snood”; “wristlets”; work gloves; leggings; “metatarsal”
boots; safety glasses; earplugs; and a respirator.2 At bot-
tom, petitioners want to be paid for the time they have
spent putting on and taking off those objects. In the ag-
gregate, the amount of time—and thus money—involved is
likely to be quite large. Because this donning-and-doffing
time would otherwise be compensable under the Act, U. S.
Steel’s contention of noncompensability stands or falls
upon the validity of a provision of its collective-bargaining
agreement with petitioners’ union, which says that this
time is noncompensable.3 The validity of that provision
depends, in turn, upon the applicability of 29 U. S. C.
§203(o) to the time at issue. That subsection allows par-
ties to decide, as part of a collective-bargaining agreement,
that “time spent in changing clothes . . . at the beginning
or end of each workday” is noncompensable.
   The District Court granted summary judgment in perti-
nent part to U. S. Steel, holding that donning and doffing
——————
    2 The
        opinions below include descriptions of some of the items. See
678 F. 3d 590, 592 (CA7 2012); 2009 WL 3430222, *2, *6. And the
opinion of the Court of Appeals provides a photograph of a male model
wearing the jacket, pants, hardhat, snood, gloves, boots, and glasses.
678 F. 3d, at 593.
  3 The District Court concluded that the collective-bargaining agree-

ment provided that the activities at issue here were noncompensable,
2009 WL 3430222, *10, and the Seventh Circuit upheld that conclusion,
678 F. 3d, at 595. That issue was not among the questions on which we
granted certiorari, and we take the import of the collective-bargaining
agreement to be a given.
                     Cite as: 571 U. S. ____ (2014)                    3

                          Opinion of the Court

the protective gear constituted “changing clothes” within
the meaning of §203(o). No. 2:07–CV–443 RM, 2009 WL
3430222, *4–*10 (ND Ind., Oct. 15, 2009). The District
Court further assumed that even if certain items—the
hardhat, glasses, and earplugs—were not “clothes,” the
time spent donning and doffing them was “de minimis”
and hence noncompensable. Id., at *6. The Court of
Appeals for the Seventh Circuit upheld those conclusions.
678 F. 3d 590, 593–595 (2012).4
  We granted certiorari, 568 U. S. ___ (2013), and now
affirm.
                    II. Legal Background
   The Fair Labor Standards Act, enacted in 1938, governs
minimum wages and maximum hours for non-exempt
“employees who in any workweek [are] engaged in com-
merce or in the production of goods for commerce, or [are]
employed in an enterprise engaged in commerce or in the
production of goods for commerce.” 29 U. S. C. §206(a)
(minimum wages); §207(a) (maximum hours); see §213
(exemptions). The Act provides that “employee” generally
means “any individual employed by an employer,”
§203(e)(1), and, in turn, provides that to “employ” is “to
suffer or permit to work,” §203(g).
   The Act did not, however, define the key terms “work”
and “workweek”—an omission that soon let loose a land-
slide of litigation. See IBP, Inc. v. Alvarez, 546 U. S. 21,
25–26 (2005). This Court gave those terms a broad read-
ing, culminating in its holding in Anderson v. Mt. Clemens
Pottery Co., 328 U. S. 680 (1946), that “the statutory
——————
  4 Petitioners also sought, inter alia, backpay for time spent traveling

between the locker rooms where they don and doff at least some of the
protective gear and their workstations. The District Court denied that
portion of respondent’s motion for summary judgment, 2009 WL
3430222, *11, and the Seventh Circuit reversed, 678 F. 3d, at 595–598.
That issue is not before this Court, so we express no opinion on it.
4        SANDIFER v. UNITED STATES STEEL CORP.

                     Opinion of the Court

workweek includes all time during which an employee is
necessarily required to be on the employer’s premises, on
duty or at a prescribed workplace.” Id., at 690–691. That
period, Anderson explained, encompassed time spent
“pursu[ing] certain preliminary activities after arriving
. . . , such as putting on aprons and overalls [and] remov-
ing shirts.” Id., at 692–693. “These activities,” the Court
declared, “are clearly work” under the Act. Id., at 693.
    Organized labor seized on the Court’s expansive con-
struction of compensability by filing what became known
as “portal” actions (a reference to the “portals” or entranc-
es to mines, at which workers put on their gear).
“PORTAL PAY SUITS EXCEED A BILLION,” announced
a newspaper headline in late 1946. N. Y. Times, Dec. 29,
1946, p. 1. Stating that the Fair Labor Standards Act
had been “interpreted judicially in disregard of long-
established customs, practices, and contracts between
employers and employees,” Congress responded by passing
the Portal-to-Portal Act of 1947, 61 Stat. 84, as amended,
29 U. S. C. §251 et seq. (2006 ed. and Supp. V). §251(a).
    The Portal-to-Portal Act limited the scope of employers’
liability in various ways. As relevant here, it excluded
from mandatorily compensable time
    “activities which are preliminary to or postliminary to
    [the] principal activity or activities [that an employee
    is employed to perform], which occur either prior to
    the time on any particular workday at which such
    employee commences, or subsequent to the time on
    any particular workday at which he ceases, such prin-
    cipal activity or activities.” 61 Stat. 87, 29 U. S. C.
    §254(a)(2).
   The Department of Labor promulgated a regulation
explaining that the Portal-to-Portal Act did not alter what
is known as the “continuous workday rule,” under which
compensable time comprises “the period between the
                  Cite as: 571 U. S. ____ (2014)              5

                      Opinion of the Court

commencement and completion on the same workday of an
employee’s principal activity or activities . . . [,] whether or
not the employee engages in work throughout all of that
period.” 12 Fed. Reg. 7658 (1947); 29 CFR §790.6(b)
(2013). Of particular importance to this case, a Labor
Department interpretive bulletin also specified that
whereas “changing clothes” and “washing up or shower-
ing” “would be considered ‘preliminary’ or ‘postliminary’
activities” when “performed outside the workday and . . .
under the conditions normally present,” those same activi-
ties “may in certain situations be so directly related to the
specific work the employee is employed to perform that
[they] would be regarded as an integral part of the em-
ployee’s ‘principal activity.’ ” 12 Fed. Reg. 7659, and n. 49;
29 CFR §790.7, and n. 49.
   In 1949, Congress amended the Fair Labor Standards
Act to address the conduct discussed in that interpretive
bulletin—changing clothes and washing—by adding the
provision presently at issue:
    “Hours Worked.—In determining for the purposes of
    [the minimum-wage and maximum-hours sections] of
    this title the hours for which an employee is em-
    ployed, there shall be excluded any time spent in
    changing clothes or washing at the beginning or end
    of each workday which was excluded from measured
    working time during the week involved by the express
    terms of or by custom or practice under a bona fide
    collective-bargaining agreement applicable to the par-
    ticular employee.” 63 Stat. 911, 29 U. S. C. §203(o).
Simply put, the statute provides that the compensability
of time spent changing clothes or washing is a subject
appropriately committed to collective bargaining.
  In Steiner v. Mitchell, 350 U. S. 247 (1956), the Court
echoed the Labor Department’s 1947 regulations by hold-
ing that “changing clothes and showering” can, under
6            SANDIFER v. UNITED STATES STEEL CORP.

                        Opinion of the Court

some circumstances, be considered “an integral and indis-
pensable part of the principal activities for which covered
workmen are employed,” reasoning that §203(o) “clear[ly]
impli[ed]” as much. Id., at 254–256. And in IBP, we
applied Steiner to treat as compensable the donning and
doffing of protective gear somewhat similar to that at
issue here, 546 U. S., at 30. We said that “any activity
that is ‘integral and indispensable’ to a ‘principal activity’
is itself a ‘principal activity’ ” under §254(a), id., at 37.
   As relevant to the question before us, U. S. Steel does
not dispute the Seventh Circuit’s conclusion that “[h]ad
the clothes-changing time in this case not been rendered
noncompensable pursuant to [§]203(o), it would have been
a principal activity.” 678 F. 3d, at 596. Petitioners, how-
ever, quarrel with the premise, arguing that the donning
and doffing of protective gear does not qualify as “chang-
ing clothes.”
                        III. Analysis
                        A. “Clothes”
   We begin by examining the meaning of the word
“clothes.”5 It is a “fundamental canon of statutory con-
struction” that, “unless otherwise defined, words will be
interpreted as taking their ordinary, contemporary, com-
mon meaning.” Perrin v. United States, 444 U. S. 37, 42
(1979).
   Dictionaries from the era of §203(o)’s enactment indicate
that “clothes” denotes items that are both designed and
used to cover the body and are commonly regarded as
articles of dress. See Webster’s New International Dic-
tionary of the English Language 507 (2d ed. 1950) (Web-
ster’s Second) (defining “clothes” as “[c]overing for the
——————
    5 Althoughthe Labor Department has construed §203(o) on a number
of occasions, the Government has expressly declined to ask us to defer
to those interpretations, which have vacillated considerably over the
years.
                 Cite as: 571 U. S. ____ (2014)            7

                     Opinion of the Court

human body; dress; vestments; vesture”); see also, e.g., 2
Oxford English Dictionary 524 (1933) (defining “clothes”
as “[c]overing for the person; wearing apparel; dress,
raiment, vesture”). That is what we hold to be the mean-
ing of the word as used in §203(o). Although a statute
may make “a departure from the natural and popular
acceptation of language,” Greenleaf v. Goodrich, 101 U. S.
278, 284–285 (1880) (citing Maillard v. Lawrence, 16 How.
251 (1854)), nothing in the text or context of §203(o) sug-
gests anything other than the ordinary meaning of
“clothes.”
   Petitioners argue that the word “clothes” is too indeter-
minate to be ascribed any general meaning but that,
whatever it includes, it necessarily excludes items de-
signed and used to protect against workplace hazards.
That position creates a distinction between “protection,”
on the one hand, and “decency or comfort,” on the other—a
distinction that petitioners appear to have derived from
Webster’s Second, which elaborates that “clothes” is “a
general term for whatever covering is worn, or is made to
be worn, for decency or comfort.” Webster’s Second 507
(emphasis added). But that definition does not exclude,
either explicitly or implicitly, items with a protective
function, since “protection” and “comfort” are not incom-
patible, and are often synonymous. A parasol protects
against the sun, enhancing the comfort of the bearer—just
as work gloves protect against scrapes and cuts, enhanc-
ing the comfort of the wearer. Petitioners further assert
that protective items of apparel are referred to as “cloth-
ing” rather than “clothes.” They point out that, when
introduced by the adjective “protective,” the noun “cloth-
ing” is used more commonly than “clothes.” That is true
enough, but it seems to us explained by euphonic prefer-
ence rather than difference in meaning. We see no basis
for the proposition that the unmodified term “clothes”
somehow omits protective clothing.
8         SANDIFER v. UNITED STATES STEEL CORP.

                      Opinion of the Court

   Petitioners’ proffered distinction, moreover, runs the risk
of reducing §203(o) to near nothingness. The statutory
compensation requirement to which §203(o) provides an
exception embraces the changing of clothes only when that
conduct constitutes “an integral and indispensable part of
the principal activities for which covered workmen are
employed.” Steiner, 350 U. S., at 256. But protective gear
is the only clothing that is integral and indispensable to
the work of factory workers, butchers, longshoremen, and
a host of other occupations. Petitioners’ definition of
“clothes” would largely limit the application of §203(o) to
what might be called workers’ costumes, worn by such
employees as waiters, doormen, and train conductors.
Petitioners insist that their definition excludes only items
with some specific work-hazard-related protective func-
tion, but that limitation essentially abandons the asser-
tion that clothes are for decency or comfort, leaving no
basis whatever for the distinction.
   Petitioners’ position is also incompatible with the histor-
ical context surrounding §203(o)’s passage, since it flatly
contradicts an illustration provided by the Labor Depart-
ment’s 1947 regulations to show how “changing clothes”
could be intimately related to a principal activity. See 29
CFR §790.7, and n. 49. Those regulations cited the situa-
tion in which “an employee in a chemical plant . . . cannot
perform his [job] without putting on certain clothes” and
specified that “[s]uch a situation may exist where the
changing of clothes on the employer’s premises is required
by law, by rules of the employer, or by the nature of the
work.” 12 Fed. Reg. 7660, and n. 65; 29 CFR §790.8(c),
and n. 65. And petitioners’ position contradicts this
Court’s only prior opinion purporting to interpret §203(o).
Steiner, announced less than a decade after the statute’s
passage, suggested in dictum that, were there a pertinent
provision of a collective-bargaining agreement, §203(o)
would have applied to the facts of that case—where work-
                     Cite as: 571 U. S. ____ (2014)                   9

                         Opinion of the Court

ers “ma[d]e extensive use of dangerously caustic and toxic
materials, and [we]re compelled by circumstances, includ-
ing vital considerations of health and hygiene, to change
clothes” on the job site. 350 U. S., at 248, 254–255.
  Petitioners contend that any attempt at a general defi-
nition of “clothes” will cast a net so vast as to capture all
manner of marginal things—from bandoliers to barrettes
to bandages. Yet even acknowledging that it may be
impossible to eliminate all vagueness when interpreting a
word as wide-ranging as “clothes,” petitioners’ fanciful
hypotheticals give us little pause. The statutory context
makes clear that the “clothes” referred to are items that
are integral to job performance; the donning and doffing of
other items would create no claim to compensation under
the Act, and hence no need for the §203(o) exception.
Moreover, even with respect to items that can be regarded
as integral to job performance, our definition does not
embrace the view, adopted by some Courts of Appeals,
that “clothes” means essentially anything worn on the
body—including accessories, tools, and so forth. See, e.g.,
Salazar v. Butterball, LLC, 644 F. 3d 1130, 1139–1140
(CA10 2011) (“clothes” are “items or garments worn by a
person” and include “knife holders”). The construction
we adopt today is considerably more contained. Many
accessories—necklaces and knapsacks, for instance—are not
“both designed and used to cover the body.” Nor are tools
“commonly regarded as articles of dress.” Our definition
leaves room for distinguishing between clothes and wear-
able items that are not clothes, such as some equipment
and devices.6
  Respondent and its amici, by contrast, give the term in
——————
   6 Petitioners and their amici insist that equipment can never be

clothes. While we do not believe that every wearable piece of equip-
ment qualifies—for example, a wristwatch—our construction of
“clothes” does not exclude all objects that could conceivably be charac-
terized as equipment.
10       SANDIFER v. UNITED STATES STEEL CORP.

                     Opinion of the Court

question a capacious construction, effectively echoing the
Courts of Appeals mentioned above.          On this view,
“clothes” encompasses the entire outfit that one puts on to
be ready for work. That interpretation is, to be sure, more
readily administrable, but it is even more devoid of a
textual foundation than petitioners’ offering. Congress
could have declared bargainable under §203(o) “time spent
in changing outfits,” or “time spent in putting on and off
all the items needed for work.” For better or worse, it used
the narrower word “clothes.” “The role of this Court is to
apply the statute as it is written—even if we think some
other approach might accord with good policy.” Burrage v.
United States, ante at 14 (internal quotation marks and
brackets omitted).
                          B. “Changing”
    Having settled upon the meaning of “clothes,” we must
now consider the meaning of “changing.” Petitioners
assert that when used with certain objects—such as “tire,”
“diaper,” or, indeed, “clothes”—the term “changing” connotes
substitution. That is undoubtedly true. See Webster’s
Second 448 (defining “change” as “to make substitution
of, for, or among, often among things of the same kind
. . . ; as, to change one’s clothes”). One would not normally
say he has changed clothes when he puts on an overcoat.
Petitioners conclude from this that items of protective gear
that are put on over the employee’s street clothes are not
covered by §203(o).
    We disagree. Although it is true that the normal mean-
ing of “changing clothes” connotes substitution, the phrase
is certainly able to have a different import. The term
“changing” carried two common meanings at the time of
§203(o)’s enactment: to “substitute” and to “alter.” See,
e.g., 2 Oxford English Dictionary 268 (defining “change,”
among other verb forms, as “to substitute another (or
others) for, replace by another (or others)” and “[t]o make
                     Cite as: 571 U. S. ____ (2014)                  11

                         Opinion of the Court

(a thing) other than it was; to render different, alter,
modify, transmute”). We think that despite the usual
meaning of “changing clothes,” the broader statutory
context makes it plain that “time spent in changing
clothes” includes time spent in altering dress.
  The object of §203(o) is to permit collective bargaining
over the compensability of clothes-changing time and to
promote the predictability achieved through mutually
beneficial negotiation. There can be little predictability,
and hence little meaningful negotiation, if “changing”
means only “substituting.” Whether one actually ex-
changes street clothes for work clothes or simply layers
garments atop one another after arriving on the job site is
often a matter of purely personal choice. That choice may
be influenced by such happenstances and vagaries as what
month it is, what styles are in vogue, what time the em-
ployee wakes up, what mode of transportation he uses,
and so on. As the Fourth Circuit has put it, if the statute
imposed a substitution requirement “compensation for
putting on a company-issued shirt might turn on some-
thing as trivial as whether the employee did or did not
take off the t-shirt he wore into work that day.” Sepulveda
v. Allen Family Foods, Inc., 591 F. 3d 209, 216 (2009).
Where another reading is textually permissible, §203(o)
should not be read to allow workers to opt into or out of its
coverage at random or at will.7

——————
  7 This Court has stated that “exemptions” in the Fair Labor Stand-

ards Act “are to be narrowly construed against the employers seeking to
assert them.” Arnold v. Ben Kanowsky, Inc., 361 U. S. 388, 392 (1960).
We need not disapprove that statement to resolve the present case.
The exemptions from the Act generally reside in §213, which is entitled
“Exemptions” and classifies certain kinds of workers as uncovered by
various provisions. Thus, in Christopher v. SmithKline Beecham Corp.,
567 U. S. ___, ___–___, n. 21 (2012) (slip op., at 19–20, n. 21), we de-
clared the narrow-construction principle inapplicable to a provision
appearing in §203, entitled “Definitions.”
12        SANDIFER v. UNITED STATES STEEL CORP.

                      Opinion of the Court

                        C. Application
  Applying the foregoing principles to the facts of this
case, we hold that petitioners’ donning and doffing of the
protective gear at issue qualifies as “changing clothes”
within the meaning of §203(o).
  Petitioners have pointed to 12 particular items: a flame-
retardant jacket, pair of pants, and hood; a hardhat; a
snood; wristlets; work gloves; leggings; metatarsal boots;
safety glasses; earplugs; and a respirator. The first nine
clearly fit within the interpretation of “clothes” elaborated
above: they are both designed and used to cover the body
and are commonly regarded as articles of dress. That
proposition is obvious with respect to the jacket, pants,
hood, and gloves. The hardhat is simply a type of hat.
The snood is basically a hood that also covers the neck and
upper shoulder area; on the ski slopes, one might call it a
“balaclava.” The wristlets are essentially detached shirt-
sleeves. The leggings look much like traditional legwarm-
ers, but with straps. And the metatarsal boots—more
commonly known as “steel-toed” boots—are just a special
kind of shoe.
  The remaining three items, by contrast, do not satisfy
our standard. Whereas glasses and earplugs may have a
covering function, we do not believe that they are commonly
regarded as articles of dress. And a respirator obviously
falls short on both grounds. The question is whether the
time devoted to the putting on and off of these items must
be deducted from the noncompensable time. If so, federal
judges must be assigned the task of separating the
minutes spent clothes-changing and washing from the
minutes devoted to other activities during the period in
question.
  Some Courts of Appeals, including the Court of Appeals
in this case, have sought to avoid, or at least mitigate, this
difficulty by invoking the doctrine de minimis non curat
lex (the law does not take account of trifles). This, they
                     Cite as: 571 U. S. ____ (2014)                   13

                          Opinion of the Court

hold, enables them to declare noncompensable a few
minutes actually spent on something other than clothes-
changing—to wit, donning and doffing non-clothes items.
    Although the roots of the de minimis doctrine stretch to
ancient soil, its application in the present context began
with Anderson. There, the Court declared that because
“[s]plit-second absurdities are not justified by the actuali-
ties of working conditions or by the policy of the Fair
Labor Standards Act,” such “trifles” as “a few seconds or
minutes of work beyond the scheduled working hours”
may be “disregarded.” 328 U. S., at 692. “We [thus] do not
. . . preclude the application of a de minimis rule.” Ibid.
    We doubt that the de minimis doctrine can properly be
applied to the present case. To be sure, Anderson included
“putting on aprons and overalls” and “removing shirts” as
activities to which “it is appropriate to apply a de minimis
doctrine.” Id., at 692–693. It said that, however, in the
context of determining what preliminary activities had to
be counted as part of the gross workweek under §207(a) of
the Fair Labor Standards Act.8 A de minimis doctrine
does not fit comfortably within the statute at issue here,
which, it can fairly be said, is all about trifles—the rela-
tively insignificant periods of time in which employees
wash up and put on various items of clothing needed for
their jobs. Or to put it in the context of the present case,
there is no more reason to disregard the minute or so
necessary to put on glasses, earplugs, and respirators,
than there is to regard the minute or so necessary to put
on a snood. If the statute in question requires courts to
——————
   8 We note, moreover, that even in that context, the current regula-

tions of the Labor Department apply a stricter de minimis standard
than Anderson expressed. They specify that “[a]n employer may not
arbitrarily fail to count as hours worked any part, however small, of the
employee’s fixed or regular working time or practically ascertainable
period of time he is regularly required to spend on duties assigned to
him.” 29 CFR §785.47.
14        SANDIFER v. UNITED STATES STEEL CORP.

                      Opinion of the Court

select among trifles, de minimis non curat lex is not Latin
for close enough for government work.
   That said, we nonetheless agree with the basic percep-
tion of the Courts of Appeals that it is most unlikely
Congress meant §203(o) to convert federal judges into
time-study professionals. That is especially so since the conse-
quence of dispensing with the intricate exercise of separat-
ing the minutes spent clothes-changing and washing from
the minutes devoted to other activities is not to prevent
compensation for the uncovered segments, but merely to
leave the issue of compensation to the process of collective
bargaining. We think it is possible to give the text of
§203(o) a meaning that avoids such relatively inconse-
quential judicial involvement in “a morass of difficult, fact-
specific determinations,” Sepulveda, 591 F. 3d, at 218.
   The forerunner of §203(o)—the Portal-to-Portal Act
provision whose interpretation by the Labor Department
prompted its enactment—focused narrowly on the activi-
ties involved: “activities which are preliminary to or
postliminary to [the employee’s] principal activity or activ-
ities.” §254(a)(2). Section 203(o), by contrast, is addressed
not to certain “activities,” but to “time spent” on certain
activities, viz., “changing clothes or washing.” Just as one
can speak of “spending the day skiing” even when less-
than-negligible portions of the day are spent having lunch
or drinking hot toddies, so also one can speak of “time
spent changing clothes and washing” when the vast pre-
ponderance of the period in question is devoted to those
activities. To be sure, such an imprecise and colloquial
usage will not ordinarily be attributed to a statutory text,
but for the reasons we have discussed we think that ap-
propriate here. The question for courts is whether the
period at issue can, on the whole, be fairly characterized as
“time spent in changing clothes or washing.” If an em-
ployee devotes the vast majority of the time in question to
putting on and off equipment or other non-clothes items
                 Cite as: 571 U. S. ____ (2014)                 15

                     Opinion of the Court

(perhaps a diver’s suit and tank) the entire period would
not qualify as “time spent in changing clothes” under
§203(o), even if some clothes items were donned and doffed
as well. But if the vast majority of the time is spent in
donning and doffing “clothes” as we have defined that
term, the entire period qualifies, and the time spent put-
ting on and off other items need not be subtracted.
  In the present case, the District Court stated that “the
time expended by each employee donning and doffing”
safety glasses and earplugs “is minimal,” 2009 WL
3430222, *6, a conclusion with which the Seventh Circuit
agreed, 678 F. 3d, at 593. As for respirators, the District
Court stated that they “are kept and put on as needed at
job locations,” 2009 WL 3430222, *2, which would render
the time spent donning and doffing them part of an em-
ployee’s normal workday and thus beyond the scope of
§203(o). The Seventh Circuit did not address respirators
at all, and we are not inclined to disturb the District
Court’s factual conclusion.
                      *    *     * 

  The judgment of the Court of Appeals is affirmed. 


                                                  It is so ordered.
