withstanding petitioner's challenge, the Board's conclusion that "the possibility of any disruption in patient care resulting from solicitation or distribution of literature is remote," St. John's Hospital & School of Nursing, Inc., 222 N. L. R. B., at 1151, as applied to petitioner's cafeteria, is fully supported by the record. The Board had before it evidence that patients' meals are provided in their rooms. A patient is not allowed to visit the cafeteria unless his doctor certifies that he is well enough to do so. Thus, patient use of the cafeteria is voluntary, random, and infrequent. It is of critical significance that only 1.56% of the cafeteria's patrons are patients. Patients who frequent the cafeteria would not expect to receive special attention or primary care there and any unusually sensitive to seeing union literature distributed or overhearing discussions about unionism, readily could avoid the cafeteria without interfering with the hospital's program of care. Especially telling is the fact that petitioner, under compulsion of the Massachusetts Labor Commission, permitted limited union solicitation in the cafeteria for a significant period, apparently without untoward effects, and that petitioner, who logically is in the best position to offer evidence on the point, was unable to introduce any evidence to show that solicitation or distribution was or would be harmful.19

There was also cogent evidence that petitioner itself recognized that at least some solicitation and distribution would not upset patients and undermine its function of providing quality medical care. It thus appears that petitioner's rule was more restrictive than necessary to avert that result.20

19 Cf. International Harvester Co. v. Ruckelshaus, 155 U. S. App. D. C. 411, 439, 478 F. 2d 615, 643 (1973).

20 Evidence that petitioner adopted a less restrictive approach to behavior in the cafeteria which would be at least as disquieting to patients as union solicitation further supports the Board's conclusion that the risk of harm to patients is not so great as to justify an unlimited restriction. Petitioner advised its professional staff of complaints voiced by patients and visitors

Petitioner had permitted use of the cafeteria for other types of solicitation, including fund drives, which, if not to be equated with union solicitation in terms of potential for generating controversy, at least indicates that the hospital regarded the cafeteria as sufficiently commodious to admit solicitation and distribution without disruption." While in other contexts, it has been recognized that organizational activity can result in behavior which, as petitioner argues and we agree, would be undesirable in the hospital's cafeteria,22 the Board has not foreclosed the hospital from imposing less restrictive means of regulating organizational activity more nearly directed toward the harm to be avoided.23

based on overheard clinical discussions about named patients in such places as the cafeteria line. Petitioner warned that the "effect [of this on patients] can be devastating . . .," App. 136, and that "[p]atients and visitors [have been] horrified to overhear-in . . . cafeteria lines. . what is to the engrossed clinician innocuous professional discussion." Id., at 138. This kind of discussion, far more unsettling than talk of wages and working conditions, was not banned from the cafeteria; rather, petitioner merely required staff to "restrict the voicing of your clinical discussions to include none other than your intended audience." Ibid.

21 Compare Goldblatt Bros., Inc., 77 N. L. R. B. 1262 (1948), in which, explaining its decision to uphold a ban on solicitation in a department store restaurant, the Board noted:

"[I]n some of the stores the restaurant consists of a counter, in which restaurant employees on duty, other employees off duty, union organizers, and customers are in close contact with each other. Under these circumstances, union solicitation in the restaurants is as apt to disrupt the Respondent's business as is such solicitation carried on in any other portion of the store in which customers are present." Id., at 1263–1264.

22 See, e. g., McDonald's Corp., 205 N. L. R. B., at 407 n. 18 (opinion of Administrative Law Judge) ("Some solicitation might result in a pleasant and informative chat between the employees on their nonwork time in working areas. On the other hand, it might lead to a bitter exchange of insults or worse . . e . . .").

23 For example, a rule forbidding any distribution to or solicitation of nonemployees would do much to prevent potentially upsetting literature from being read by patients. Petitioner, in fact, has such a rule, see supra,

The Board was, of course, free to draw an inference from these facts in light of its experience, the validity of which "depends upon the rationality between what is proved and what is inferred."" Republic Aviation, 324 U. S., at 805 (footnote omitted). It cannot fairly be said that the inference drawn by the Board regarding the likelihood of disruption of patient care in light of this evidence was irrational. Similarly, it is the Board upon whom the duty falls in the first instance to determine the relative strength of the conflicting interests and to balance their weight. As the Court noted in Hudgens v. NLRB, 424 U. S. 507, 522 (1976), “[t]he locus of [the] accommodation [between the legitimate interests of both] may fall at differing points along the spectrum depending on the nature and strength of the respective § 7 rights and private property rights asserted in any given context." Here, the employees' interests are at their strongest,

at 486-487, and it has not been shown that organizational activity by Schunior or anyone else actually resulted in distribution to nonemployees. This rule could be readily enforced at petitioner's hospital, moreover, since employees are required to wear name tags and many do-and since security guards monitor the cafeteria. Secondly, the Board may determine that a rule requiring face-to-face distribution rather than leaving literature on a table accessible to all is a justified accommodation of §7 rights with petitioner's legitimate desire to avoid having potentially upsetting literature read by patients.

24 The requirement that decisions be supported by evidence on the record "does not go beyond the necessity for the production of evidential facts, however, and compel evidence as to the results which may flow from such facts.... An administrative agency with power after hearings to determine on the evidence in adversary proceedings whether violations of statutory commands have occurred may infer within the limits of the inquiry from the proven facts such conclusions as reasonably may be based upon the facts proven. One of the purposes which lead to the creation of such boards is to have decisions based upon evidential facts under the particular statute made by experienced officials with an adequate appreciation of the complexities of the subject which is entrusted to their administration." Republic Aviation, 324 U. S., at 800. (Citations omitted.)

for unlike the interests involved in NLRB v. Babcock & Wilcox Co., 351 U. S., at 113, "[the] activity was carried on by employees already rightfully on the employer's property." Hudgens, 424 U. S., at 521-522, n. 10. "[T]he employer's management interests rather than his property interests [are] involved. . . This difference is 'one of substance.'" Ibid. (citations omitted).

On the other hand, in the context of health-care facilities, the importance of the employer's interest in protecting patients from disturbance cannot be gainsaid. While outside of the health-care context, the availability of alternative means of communication is not, with respect to employee organizational activity, a necessary inquiry, see Babcock & Wilcox, supra, at 112-113, it may be that the importance of the employer's interest here demands use of a more finely calibrated scale. For example, the availability of one part of a health-care facility for organizational activity might be regarded as a factor required to be considered in evaluating the permissibility of restrictions in other areas of the same facility. That consideration is inapposite here, however, where the only areas in which organizational rights are permitted is not conducive to their exercise. Moreover, the area in which organizational rights are sought here is a "natural gathering are [a]" for employees, 554 F. 2d, at 481, and one in which the risk of harm to patients is relatively low as compared to potential alternative locations within the facility. On the basis of the record before it, we cannot say that the Board, in evaluating the relative strength of the competing interests, failed to consider any factor appropriately to be taken into account. Cf. Babcock & Wilcox, supra.

D

Petitioner's argument that it is irrational to hold, as the Board has, on the one hand, that a rule prohibiting solicitation in the dining area of a public restaurant is lawful because

solicitation has the tendency to upset patrons,25 while one prohibiting like activity in a hospital's cafeteria is unlawful absent evidence that nonemployee patrons would be upset, on the other, has only superficial appeal. That argument wholly fails to consider that the Board concluded that these rules struck the appropriate balance between organizational and employer rights in the particular industry to which each is applicable. In the retail marketing and restaurant industries, the primary purpose of the operation is to serve customers, and this is done on the selling floor of a store or in the dining area of a restaurant. Employee solicitation in these areas, if disruptive, necessarily would directly and substantially interfere with the employer's business. On the other hand, it would be an unusual store or restaurant which did not have stockrooms, kitchens, and other nonpublic areas, and in those areas employee solicitation of nonworking employees must be permitted. In that context, the Board concluded that, on balance, employees' organizational interests do not outweigh the employer's interests in prohibiting solicitation on the selling floor.

In the hospital context the situation is quite different. The main function of the hospital is patient care and therapy and those functions are largely performed in areas such as operating rooms, patients' rooms, and patients' lounges. The Board does not prohibit rules forbidding organizational activity in these areas. On the other hand, a hospital cafeteria, 77% of whose patrons are employees, and which is a natural gathering place for employees, functions more as an employee-service area than a patient-care area. While it is true that the fact of access by visitors and patients renders the analogy to areas such as stockrooms in retail operations less than complete, it cannot be said that when the primary function and use of the cafeteria, the availability of alternative areas of the facility in which § 7 rights effectively could be exercised, and

25 See cases cited n. 11, supra.