Rohan, J.
This is an appeal from a final decree awarding compensation to the husband , of the employee whose death was found to have resulted Arom a personal injury arising out of and in the course of her employment.
There was evidence that the employee on July 3, 1942, while at work walking along a passageway leading to a wash room, fell and struck her head against one of the trucks which were located on either side of the passageway, picked herself up and walked dizzily to a box upon which she sat holding on to her head on which there was an abrasion. She was taken to a hospital where she remained until July 24, 1942, when she was taken to a Boston hospital where she died on August 14, 1942. The record of the first hospital showed that the employee’s condition was diagnosed as “Cerebral hemorrhage (traumatic in origin),” and the record of the second hospital gave the diagnosis as “Intracranial hemorrhage probably from aneurysm or weak walled blood vessel with right hemplegia [sic], following head injury.” The death certificate stated the cause of death as “Pneumonia developed during hospitalization following cerebral lesion with symptoms following an accidental fall.” A witness who saw the employee fall testified that the employee slipped on a spot of water or oil. There was evidence that one of the nurses at the hospital removed a patch of oil from the employee’s right leg. The Industrial Accident Board adopted the findings of the single member and found that the employee’s death was due to a cerebral hemorrhage caused by slipping and falling, striking her head on a truck and suffering a physical injury which arose out of and in the course of her employment.
The principal contention of the insurer is that the employee’s fall did not result from a hazard of the employment.
The employee was acting in the course of her employment *361in going to the wash room for a pail of water. Sundine’s Case, 218 Mass. 1. Von Ette’s Case, 223 Mass. 56. Hughes’s Case, 274 Mass. 540. Nagle’s Case, 310 Mass. 193. The risk of falling against one of the trucks which flanked either side of the passageway was a risk that would be encountered by every employee whose duties brought her within the zone of this special danger. She would not have been exposed to this danger except for her employment, and the risk that she might accidentally fall against the truck was a hazard inherent in her employment. Dow’s Case, 231 Mass. 348. Hallett’s Case, 232 Mass. 49. Sullivan’s Case, 241 Mass. 9. Cusick’s Case, 260 Mass. 421. Holmes’s Case, 267 Mass. 307. Nagle’s Case, 310 Mass. 193. The fact that the board found, as it properly could upon the evidence, that she slipped upon the floor and in falling struck the truck only makes more clear the causal connection between the injury and the employment, Bagley’s Case, 256 Mass. 593; Sullivan’s Case, 265 Mass. 463, and distinguishes the case from Cinmino’s Case, 251 Mass. 158, and Rozek’s Case, 294 Mass. 205, upon which the insurer relies. These cases rest upon the principle that the fall of a workman upon a floor, which is not caused by the condition of the floor but is caused solely by his physical or mental condition which was not brought about by the strain of his employment, has not resulted in a compensable injury. Lander v. British United Shoe Machinery Co. Ltd. 26 B. W. C. C. 411. Hansen v. Turner Construction Co. 224 N. Y. 331.
The next contention of the insurer is that there was not sufficient evidence that the employee’s fall produced a cerebral hemorrhage. The insurer offered no medical testimony. The employee’s physician testified that in his opinion the fall caused a rupture of a blood vessel in the brain. He also testified that in the absence of an autopsy and with a history of weakened blood vessels his opinion would rest upon speculation and surmise, but it could be found that by speculation and surmise he meant that, after getting a history of an accident and making every possible examination of a patient who was unable to talk, he studied the facts and formulated an opinion. A reasoned conclusion *362derived from observed facts by one having special scientific knowledge cannot as matter of law be said not to rise any higher than a guess or speculation. Walker’s Case, 243 Mass. 224. Blanchard’s Case, 277 Mass. 413. Apart from the medical testimony, the hospital records and the death certificate amply warranted a finding that death from a cerebral hemorrhage followed a head injury. These records could be fairly construed as doing more than stating the sequence of events. They could be reasonably understood to mean that the hemorrhage was caused by the head injury. If one was told that death followed an accident he would ordinarily understand that death was caused by the accident. At least a trier of fact could properly come to that conclusion. Dunbar v. Ferrera Bros. Inc. 306 Mass. 90, 94. Taylor v. Metropolitan Street Railway, 183 S. W. 1129, 1132. Moreover, the statement on the death certificate that the cause of death was a cerebral lesion “following an accidental fall” was prima facie evidence of the facts., recorded and the insurer was not entitled to have the words just quoted struck out. G. L. (Ter. Ed.) c. 46, § 19. Shamlian v. Equitable Accident Co. 226 Mass. 67. Silva v. Fidelity & Casualty Co. 252 Mass. 328. Wolf’s Case, 285 Mass. 181. Dow v. United States Fidelity & Guaranty Co. 297 Mass. 34. Walcott v. Sumner, 308 Mass. 413. Lydon v. Boston Elevated Railway, 309 Mass. 205.
The diagnosis appearing in the hospital record that the employee was suffering from a “Cerebral hemorrhage (traumatic in origin) ” was a description of her physical condition and a part of the medical history of the case. It defined the nature and type of the hemorrhage. It was properly admitted in evidence. Leonard v. Boston Elevated Railway, 234 Mass. 480. Bilodeau v. Fitchburg & Leominster Street Railway, 236 Mass. 526. Clark v. Beacon Oil Co. 271 Mass. 27. There was, however, error in admitting that portion of one of the hospital records to the effect that the patient's husband had stated that she slipped upon a greasy floor. Inangelo v. Petterson, 236 Mass. 439. Kelley v. Jordan Marsh Co. 278 Mass. 101, 110, 111. Commonwealth v. Dawn, 302 Mass. 255, 261. But in view of the *363testimony of the eyewitness that the employee slipped upon a spot of water or oil and of the nurse that she removed an oil stain from the employee’s leg shortly after she was admitted to the hospital, the diagnosis of the employee’s condition as stated in the record of the first hospital, the description of her condition as contained in the record of the second hospital and the cause of death set forth in the death certificate, the error in the admission of evidence is too unsubstantial to constitute an adequate ground for the reversal of the final decree. Pigeon’s Case, 216 Mass. 51, 55. Beckles’s Case, 230 Mass. 272, 274. Sciola’s Case, 236 Mass. 407, 413. Fernald’s Case, 240 Mass. 567. Indrisano’s Case, 307 Mass. 520.
This is not a case where costs should be allowed under G. L. (Ter. Ed.) c. 152, § 14. See G. L. (Ter. Ed.) c. 152, § 11, as amended by St. 1939, c. 213.
Decree affirmed.