In each of these consolidated cases, the plaintiff appeals from a decision of the Workers’ Compensation Appeal Board (WCAB) which denied disability benefits for injuries suffered as a result of a fall while performing job tasks on their respective employer’s premises. Each claimant sought this Court’s leave to appeal, but the applications were denied. On application for leave to appeal to the Supreme Court, the causes were remanded to this Court for consideration as on leave granted. 417 Mich 851 (1982).
Plaintiff Larry McClain suffered injuries when he became dizzy and fell on November 2, 1976, while working on the assembly line at Chrysler’s Lynch Road Assembly Plant in Detroit. His job was to attach nuts and bolts to sway bars that came along the conveyor belt and involved considerable stooping and bending. On the date of his *726injury, he arrived at the plant approximately one-half hour before his shift began and walked around the plant, including the welding, painting and upholstering shops.
Although he "felt good” when he arrived at work, he began to feel tired and dizzy when he started working. He called his supervisor after 15 or 20 minutes of work and asked to be relieved. The supervisor told him to walk around to see if he felt better. He took three steps and fainted, striking his head on the floor and sustaining serious injuries to his chin, jaw and teeth. Plaintiff testified to the presence of fumes in some of the shops which he passed through before starting his shift and stated he had never previously had any problem with dizziness and had no serious health problems.
The hearing referee denied benefits, finding that plaintiff suffered an "idiopathic” fall and that he had failed to establish a "causative thread” between employment and the injury. On appeal the WCAB affirmed, finding as a matter of fact that plaintiff had failed to sustain his burden of proof in establishing that the fall was work related. Because the plaintiff failed to show that the injury arose out of his employment, the board denied benefits.
Plaintiff Carol Ann Gapinski sustained injuries when she became dizzy and fell on September 13, 1977, while working as a molding machine operator at the plant of defendant Mayfair Plastics. Plaintiff testified that, on the date of her injury, she was approximately four months pregnant and "felt really good” when she came to work. She began feeling dizzy while working, stepped off a piece of cardboard approximately 1/2 inch thick which she had been standing on and fell straight back, striking her head on a concrete floor. A fan *727next to her work station was knocked over in connection with her fall. She testified she had never had dizzy spells before, including during a prior pregnancy.
As a result of the fall, plaintiff sustained head injuries which led to a partial hearing loss in one ear and a "constant ringing sound”. From that point forward, she continued having dizzy spells which occurred less frequently as time passed. Although no one witnessed the fall, plaintiff’s supervisor heard the noise and found her unconscious, lying approximately six feet from her molding machine. Deposition testimony of her treating physician established the physical injuries sustained. He could offer no opinion, however, as to the cause of the fall because he testified he had no knowledge of what had occurred.
The hearing referee determined plaintiff was entitled to disability benefits for a period until she went on pregnancy leave. Both sides appealed, and the WCAB reversed the finding relying on Ledbetter v Michigan Carton Co, 74 Mich App 330; 253 NW2d 753 (1977). The board held that plaintiff was not entitled to any benefits because her proofs did not relate her dizziness with her employment. It concluded that her fall was of unknown cause or origin.
The central issue presented in these cases is whether the plaintiffs sustained their burden of proof in establishing that the unexplained falls arose out of their employment. Michigan workers’ compensation law provides: "An employee, who receives a personal injury arising out of and in the course of employment by an employer who is subject to this act at the time of the injury, shall be paid compensation as provided in this act.” MCL 418.301; MSA 17.237(301).
Workers’ compensation claimants carry the bur*728den of proving causation by a preponderance of the evidence. "In all successful worker’s compensation cases, the claimant must establish by a preponderance of the evidence both a personal injury and a relationship between the injury and the workplace.” Miklik v Michigan Special Machine Co, 415 Mich 364, 367; 329 NW2d 713 (1982). See, also, Young v K Mart Corp, 123 Mich App 789; 333 NW2d 359 (1983).
In McClain, the WCAB concluded that "[pjroofs submitted on this record do not sustain his burden of proof that his loss of consciousness and fall were in any way related to his work. We so find as fact”. In Gapinski, the WCAB found that "[plaintiff’s proofs have not related her dizziness with her work”.
Findings of fact in workers’ compensation cases will not be set aside in the absence of fraud if there is evidence in the record to support such findings. Const 1963, art 6, § 28; MCL 418.861; MSA 17.237(861). A review of the record in each of these cases persuades us that the WCAB’s findings of fact should not be set aside since the evidence (or lack of it) allows a conclusion that each plaintiff failed to sustain his or her burden of proof regarding causation.
In each case, the claimant presented no expert testimony concerning causation. The WCAB was free to reject McClain’s speculation that his fall may have been caused by his reaction to fumes or by repeated bending required to perform his job. Likewise, the WCAB was free to refuse to rely on Gapinski’s speculation that she may have been made dizzy from fumes emanating from her machine or that her work station and conditions constituted substantial employment contribution to the injury.
This Court will, however, reverse where the *729WCAB has operated within the wrong legal framework or has employed incorrect legal standards in reaching its decision. Koschay v Barnett Pontiac, Inc, 386 Mich 223; 191 NW2d 334 (1971); Schaefer v Williamston Community Schools, 117 Mich App 26; 323 NW2d 577 (1982). Both plaintiffs claim that the employer has the burden of proving that the fall is idiopathic where the plaintiff establishes that the injury arises out of an employment setting characterized as a positional or neutral risk. They rely principally on the case of Whetro v Awkerman, 383 Mich 235; 174 NW2d 783 (1970), in support of this proposition. In Whetro, plaintiff was injured when a tornado destroyed the residence in which he was working for his employer. The Supreme Court affirmed the award of benefits, holding that Michigan law did not require the establishment of a proximately causal connection between the employment and the injury.
McClain argues that the requisite causal connection is shown by the chronological sequence in which his injuries occurred. As an alternative, McClain argues that his case involves a neutral risk, and thus is compensable under Whetro because the employment was the occasion of the injury.
Gapinski argues that, under Whetro, a prima facie case of compensability is made out when the following elements are established by the plaintiff’s proofs: (1) that the plaintiff sustained a personal injury; (2) that the employment was the occasion of that personal injury; and (3) that the plaintiff is disabled as a result of that personal injury. The positional or neutral risk doctrine relied on by plaintiffs is discussed by Professor Larson as follows:
"An increasing number of courts are beginning to *730make awards whenever the injury occurred because the employment required the claimant to occupy what turned out to be a place of danger. A few frankly state that causal connection is sufficiently established whenever it brings claimant to the position where he is injured. Unexplained falls and deaths occurring in the course of employment are generally held compensable, sometimes on the strength of a presumption, either judicial or statutory, that injury or death occurring in the course of employment also arises out of the employment in the absence of evidence to the contrary.” 1 Larson, Workmens’ Compensation Law, § 10.00.
We are not persuaded that Michigan has adopted a rule requiring compensation to be paid simply because the injury occurred at the workplace, where the nature of the cause is unknown. The Whetro Court ruled that compensation should be paid if the employment is the occasion of the injury, even though not the proximate cause. This does not mean, however, that all "neutral risk” injuries are necessarily compensable.
Professor Larson indicates that risks are classified as neutral for one of two reasons: (1) the nature of the risk may be known, but may be associated neither with the employment nor the employee personally; (2) the nature of the cause of harm may be simply unknown, such as an unexplained fall in the course of employment. Larson, supra, § 10.30. The tornado-caused injury in Whetro falls in the first category and is thus compensable, but there is no decision allowing compensation for injuries falling in the second category.
In Ledbetter, the Court affirmed the denial of benefits to the widow of a worker who collapsed at work and fell to the concrete floor, suffering a fractured skull and massive acute subdural hematoma. In reaching that decision, the Court stated as follows:
*731"We do not believe the sole fact that the decedent’s fall occurred on the employer’s premises justifies an award of dependency benefits to his widow.” 74 Mich App 334.
"In personal risk cases, including idiopathic fall situations, the sole fact that the injury occurred on the employer’s premises does not supply enough of a connection between the employment and the injury. Unless some showing can be made that the location of the fall aggravated or increased the injury, compensation benefits should be denied.” 74 Mich App 335-336.
McClain argues that Ledbetter is distinguishable because it involved a personal risk situation as opposed to the claimed neutral risk presented here. Gapinski claims that the factual background in her case prohibits the application of Ledbetter because her work environment increased the risk of her injury.
As noted above, findings of fact by the WCAB shall not be set aside if they are supported by evidence on the record. The claims of the plaintiffs regarding the facts and circumstances surrounding their falls were presented to the WCAB. The WCAB found contrary to the plaintiffs’ assertions, and we shall not alter those findings of fact because the record in each case supports the findings made by the WCAB.
It is also important to note that the Legislature has created a statutory presumption that certain injuries can arise "in the course of’ one’s employment. MCL 418.301(3); MSA 17.237(301X3). There is no corresponding statutory presumption for the "arising out of’ requirements of the statute. We are not prepared to conclude that the occurrence of an injury on the employer’s premises in the course of employment establishes a prima facie showing that the injury arose out of the employ*732ment, thus changing the burden of going forward with the evidence to the defendant.
In our opinion, the WCAB properly applied the legal standard requiring proof of work-relatedness by a preponderance of the evidence. We do not find that the WCAB erred by failing to devise a more specific standard relating to idiopathic falls. Plaintiffs’ arguments for compensation for injuries of unknown causal relationship to their employment have merit, but are not a recognized theory in this state.
Affirmed.