WEISBERGER, J.

This is an employee's original petition brought under the Workers' Compensation Act whereby the employee sought benefits for loss of use and disfigurement of his upper right arm. The trial commissioner found that the employee had failed to prove by a fair preponderance of the credible evidence that he sustained any injury to his right arm arising out of and in the course of his employment. The employee appealed to the full commission which found that the employee was acting outside the scope of his employment when he sustained the injury. The case is before us on the employee's appeal from the decree of the full commission affirming the earlier decree rendered pursuant to the decision of the trial commissioner.

The facts are undisputed. The employee was engaged as a so-called "hot-box operator." There was an area on the premises of the employer known as the cafeteria in which several food and beverage vending machines were located for the use of the employees. A metal grate-type fence was installed in front of the machines to prevent thievery. The fence was not installed by the employer.

A caterer visited the employer's premises at 9 a.m. and at 12 noon each day to sell sandwiches and pastry to the employees on their break. At these times the fence was unlocked and opened allowing the employees to gain access to the various vending machines. The employee stated that at other times during the day when the fence was closed, the employees could use the vending machines by placing their arms through the opening in the grate. It was customary for the employees to use the machines in this manner. The employer was aware of this practice and did not prohibit the employees from making these purchases during the period when the grate was closed and locked.

On August 21, 1975, at approximately 8 a.m. at a time when the fence was closed, the employee approached the coffee machine and inserted two coins into the machine by reaching through the grate with his right hand. The employee stated at the hearing before the trial commissioner that the opening in the grate was just large enough to permit an arm to reach the machines, insert the coins and remove the coffee. One of the coins became wedged or stuck in the machine which prevented the machine from functioning properly. The employee testified he gave the machine a "whack" with his right hand and as he did, he struck the upper part of his right arm on the grate. Shortly thereafter, the arm began to swell. The employee showed his arm to his supervisor who sent the employee to the plant nurse. A large lump developed in the area of the biceps of the employee's right arm, but he was able to continue working and did not lose any time from work as a result of this incident.

The employee stated that the only restriction placed on the use of the machines was that employees were not allowed to remain in the vending machine area at times other than the permitted breaks. Once they had made their purchase, they were required to return to their work area.

An orthopedic surgeon testified that he examined the employee on November 11, 1976. The examination revealed the employee had a rupture of the biceps muscle of the right arm. It was the doctor's opinion that the employee had a permanent ten percent loss of use of the right upper extremity.

The full commission determined that the employee's injury was sustained during the course of employment but did not arise from employment because the employee's action in exerting force on the vending machine was unusual or remote from the customary practice. Consequently, the full commission determined that the employee was injured when acting outside the scope of employment, and denied benefits.

In reviewing this case we note that we have historically applied two distinct standards in reviewing decrees of the Workers' Compensation Commission awarding or denying benefits on the ground that the employee's injury did or did not arise out of and in the course of employment. In certain instances we have regarded the determination that an injury did or did not arise out of and in the course of employment as factual in nature and applied a limited review to determine whether the commission's conclusion was supported by competent legal evidence. See, e.g., Beauchesne v. David London Co., 118 R.I. 651, 375 A.2d 920 (1977); Knowlton v. Porter Trucking Co., 117 R.I. 28, 362 A.2d 131 (1976); San Antonio v. Al Izzi's Motor Sales, Inc., 110 R.I. 54, 290 A.2d 59 (1972); Chase v. General Electric Co., 83 R.I. 269, 115 A.2d 683 (1955); Remington v. Louttit Laundry Co., 77 R.I. 185, 74 A.2d 442 (1950); Johnson v. Rhode Island Contracting Co., 73 R.I. 238, 54 A.2d 412 (1947); Bride v. Cathedral Art Metal Co., 66 R.I. 331, 19 A.2d 317 (1941).

In other instances we have stated, as both parties contend in the present case, that the legal significance of undisputed facts is to be determined by this court. See, e.g., Lussier v. American Textile Co., 110 R.I. 299, 292 A.2d 226 (1972); Bergeron v. Kilnic Co., 108 R.I. 313, 274 A.2d 753 (1971); Corry v. Commissioned Officers' Mess, 78 R.I. 264, 81 A.2d 689 (1951); Lupoli v. Atlantic Tubing Co., 43 R.I. 299, 111 A. 766 (1920). In some of these cases we have accordingly substituted our judgment on the issue of whether an injury arose out of or in the course of employment. See, e.g., Bergeron; Corry, both supra.

Clearly, the standard in reviewing the commission's conclusion on whether an injury arose out of or in the course of employment should not depend on the existence of disputed facts. See Cardillo v. Liberty Mutual Insurance Co., 330 U.S. 469, 67 S.Ct. 801, 91 L.Ed. 1028 (1947); Young v. Henry M. Young, Inc., 56 A.D.2d 941, 392 N.Y.S.2d 502 (1977); cf. Clarke v. Rhode Island Electric Lighting Co., 16 R.I. 463, 17 A. 59 (1889) (negligence case); Weiner, The Civil Jury Trial and the Law-Fact Distinction, 54 Calif. L. Rev. 1867, 1880 (1966) (negligence). Fact-finding is clearly within the commission's province and we review only to determine if there is competent legal evidence supporting those findings. Veloso v. Lebanon Knitting Mills, Inc., 111 R.I. 41, 298 A.2d 804 (1973). Once the commission has found the facts it must conclude whether the employee's injury arose out of and in the course of employment, and our review of that conclusion rests upon the facts as found by the commission.

We are empowered under the Workers' Compensation statute to review a decree of the commission on the ground that it was procured by fraud or that the commission erred on questions of law or equity. G.L. 1956 (1968 Reenactment) § 28-35-30. Thus, our ability to review a decree of the commission denying benefits on the ground that the employee's injury did not arise out of the employment rests, at least analytically, on a characterization of that determination as a question of law or fact. Many eminent authorities have wrestled with the distinction between law and fact in the realm of administrative law with no discernible product. Indeed, John Dickinson noted in his frequently cited Administrative Justice and the Supremacy of Law, 55 (1927) that:

"In truth, the distinction between 'questions of law' and 'questions of fact' really gives little help in determining how far the courts will review; and for the good reason that there is no fixed distinction. They are not two mutually exclusive kinds of questions, based upon a difference of subject-matter. Matters of law grow downward into roots of fact, and matters of fact reach upward, without a break, into matters of law. The knife of policy alone effects an artificial cleavage at the point where the court chooses to draw the line between public interest and private right. It would seem that when the courts are unwilling to review, they are tempted to explain by the easy device of calling the question one of 'fact'; and when otherwise disposed, they say that it is a question of 'law.'"

See also Landis, The Administrative Process, 145 (1938); II Cooper, State Administrative Law, 665-66 (1965). In fact, the futility of drawing a distinction is viewed as a functional failure by one authority who has stated that:

"No two terms of legal science have rendered better service than "law" and "fact." They are basic assumptions irreducible minimums and the most comprehensive maximums at the same instant. They readily accommodate themselves to any meaning we desire to give them. In them and their kind a science of law finds its strength and durability. They are the creations of centuries. What judge has not found refuge in them. The man who could succeed in defining them would be a public enemy. They may torture the souls of language mechanicians who insist that all words and phrases must have a fixed content, but they and their flexibility are essential to the science which has to do with the control of men through the power to pass judgment on their conduct."

Green, Judge and Jury, 270-71 (1930). Professor Davis has concluded that in the field of administrative law the Supreme Court consciously abstains from discussion of the law-fact distinction to maintain discretion in selecting the appropriate standard of review — either the rational basis standard or the substitution of judgment standard. 4 Davis, Administrative Law, §§ 30.08; 30.14 (1958 Supp. 1970, 1976); See Judge Friendly's discussion in Pittston Stevedoring Corp. v. Dellaventura Corp., 544 F.2d 35 (2d Cir. 1976), aff'd sub nom. Northeast Marine Terminal Co. v. Caputo, 432 U.S. 249, 97 S.Ct. 2348, 53 L.Ed.2d 320 (1977).

The inability of courts and commentators to solve the law-fact puzzle has led these authorities to advocate a practical approach to allocating functions between the administrative body and appellate court. Davis states that a number of factors may affect a court's decision regarding the standard of review. Thus, factors such as the comparative qualifications of the agency and the courts, the quality of the particular agency and the extent of delegation of power to the agency have been considered. Davis, supra, §§ 30.09; 30.10; Jaffe, Judicial Review: Question of Law, 69 Harv. L. Rev. 239, 264 (1955).

We recognize that the Legislature delegated to the Workers' Compensation Commission the express authority to determine all compensation questions. Section 28-35-11. We, however, are empowered to review questions of law and are persuaded that the appropriate standard in reviewing the commission's decree in this case is analogous to that applied on an appellate court's direct review of a jury's verdict in a negligence case.

Negligence has been described as a mixed question of law and fact, Davis, supra, § 30.01 at 190; Bohlen, Mixed Questions of Law and Fact, 72 U. Pa. L. Rev. 111, 112 (1924); and as an application of a legal standard to a set of facts. Davis, supra, § 30.01 at 190; Morris, Law and Fact, 55 Harv. L. Rev. 1303, 1312-14 (1942); Smith v. Leuthner, 156 Conn. 422, 242 A.2d 728 (1968). Similarly, in determining whether an injury arose out of and in the course of employment the commission is applying a standard to a set of facts and this determination has been described as a mixed question of law and fact, Gallimore v. Marilyn's Shoes, 292 N.C. 399, 233 S.E.2d 529 (1977), as one of fact, Illinois Valley Irrigation, Inc. v. Industrial Commission, 66 Ill.2d 234, 362 N.E.2d 339 (1977); Deines v. Greer, 216 Kan. 548, 532 P.2d 1257 (1975); Pearl v. Associated Milk Producers, Inc., 581 P.2d 894 (Okla. 1978), and as one of fact, one of law, or a mixed question depending on the circumstances of each case. Gilbert v. Maheux, 391 A.2d 1203 (Me. 1978); Koschay v. Barnett Pontiac, Inc., 386 Mich. 223, 191 N.W.2d 334 (1971).

The dispute in labelling such questions as negligence and whether an injury arose out of and in the course of employment as fact or law produces a stalemate. Weiner, supra, 54 Calif. L. Rev. at 1874-75. Thus, commentators have continually resolved the law-fact distinction in negligence-type cases in terms of the functions of the judge and jury. See Davis, supra § 30.02 at 197-98; Weiner, supra at 1876-85; Stern, Review of Findings of Administrators, Judges and Juries: A Comparative Analysis, 58 Harv. L. Rev. 70, 109-11 (1944). In fact, one authority has stated that "the terms 'law' and 'fact' are merely short terms for the respective functions of judge and jury." Green, supra at 279.

In Rhode Island the general rule is that negligence is a question for the jury unless the facts warrant only one conclusion. Nelson v. Grilli, 117 R.I. 538, 368 A.2d 1234 (1977). Stated in another way "where the facts suggest only one reasonable inference, the trial justice may properly treat the question as a matter of law." Kennedy v. Providence Hockey Club, Inc., 119 R.I. 70, 77, 376 A.2d 329, 333 (1977) (review of a trial court's grant of defendant's motion for summary judgment). Garris v. Gloss, 111 R.I. 453, 303 A.2d 765 (1973) (appeal from grant of directed verdict for defendant); Waltz v. Aycrigg, 103 R.I. 109, 235 A.2d 338 (1967) (review of denial of defendant's motions for directed verdict and new trial).

Although the foregoing cases do not involve direct appellate review of jury verdicts on negligence issues, the standard applied in reviewing the various motions in those cases is identical to that applied by this court in Boss v. Providence Worcester Railroad, 15 R.I. 149, 1 A. 9 (1885). There the defendant petitioned this court to grant a new trial in a negligence action on the grounds that the verdict was against the weight of the evidence and that the damages awarded by the jury were excessive. In concluding that the negligence issue had properly been left to the jury, the court stated that:

"It is also equally well settled that the question as to whether or not the defendant in a given case is chargeable with negligence is ordinarily a question of fact to be determined by the jury, under proper instructions from the court as to what constitutes negligence. And the same is true with regard to contributory negligence on the part of the plaintiff. And although there are cases in which, the facts being undisputed, and being decisive of the case, it becomes the duty of the court to decide as matter of law upon the question of negligence, yet it is only in those cases where the question of fact is entirely free from doubt, and where only one conclusion can be fairly arrived at therefrom, that the court has the right to thus apply the law without the action of the jury." 15 R.I. at 154, 1 A. at 11-12.

We are convinced that a question of law is presented in reviewing whether an injury arose out of and in the course of employment when the facts, as found by the commission and supported by competent legal evidence, permit reasonable men to draw only one conclusion. This standard also comports with the well-established principle that on review we will not pass on witnesses' credibility or weigh evidence. Corey v. Hassenfeld Bros., 100 R.I. 483, 217 A.2d 82 (1966).

In the case at bar, the commission found that the employee sustained an injury during the course of his employment. The commission went on to determine that the "action of going to the cafeteria area to obtain a cup of coffee was for the petitioner's personal comfort or benefit, and under normal circumstances, any injury sustained in accomplishing this has been recognized as compensable." See, e.g., Boullier v. Samsan Co., 100 R.I. 676, 219 A.2d 133 (1966). The commission further found that the use of force by the employee to stimulate the machine either to return the coins deposited or to produce the liquid product for which he had paid was "remote or unusual from the customary or usual practice." The commission concluded that the employee was "acting outside the scope of his employment when he interjected the use of force on his own account into his method to retrieve the coin or to cause the vending machine to operate." We believe that having made the findings of fact regarding the employee's use of the machine, only one reasonable conclusion was open to the commission, and that a question of law was clearly presented.

Having determined that the employee was acting in the course of his employment in using the vending machine, and that any injury arising from normal use of the machine would have been compensable, the commission applied an incorrect standard in determining that his action in using force to stimulate the machine was remote or unusual, rendering his injury uncompensable.

We have steadfastly stated that an employee's injury is compensable if the particular facts of a case establish a causal connection or nexus between the injury and employment. Beauchesne, supra; Carvalho v. Decorative Fabrics Co., 117 R.I. 231, 366 A.2d 157 (1976). In Beauchesne we stated that:

"To find a nexus, we first attempt to determine if the injury occurred during the period of employment at a place where the employee might reasonably have been and while he was reasonably fulfilling the duties of his employment or doing something incidental thereto or to the conditions under which those duties were to be performed." 118 R.I. at 655, 375 A.2d at 922.

Accord, Di Libero v. Middlesex Construction Co., 63 R.I. 509, 9 A.2d 848 (1939). The existence of this nexus was reflected in the commission's statement that the injury would have been compensable if the employee had not "whacked" the machine. The delivery of the blow to the machine did not, however, render the injury uncompensable. We stated in D'Andrea v. Manpower, Inc., 105 R.I. 108, 249 A.2d 896 (1969), that where an employee performs a permitted act in an improper manner, injuries arising therefrom are compensable. Conversely, if he performs an act which is itself forbidden, compensation will be denied. In this case the employee's obtaining coffee was not in itself forbidden, even though the reflex action of the employee in striking the machine was ill-advised or improper. Therefore, an injury arising therefrom would still be compensable. The use of the improper method does not cause the act to cease to be one incidental to and arising out of the employment.

For the reasons stated, the employee's appeal is sustained, the decree appealed from is reversed, and the case is remanded to the Workers' Compensation Commission for entry of a decree consistent with this opinion.