Claimant Madison, a 60 year old logger of 32 years, was injured when a snag fell on him. After a hearing, an Industrial Commission referee found claimant to be an “odd lot” worker, concluding that he was totally and permanently disabled. The commission expressly adopted the referee’s findings of fact and conclusions of law and ordered payment of claimant’s disability benefits. Employer and surety appeal the commission’s decision on several grounds, including the referee’s refusal to allow the employer to supplement the record with certain post hearing evidence when the claimant was permitted to do so. We conclude that the commission erred in prohibiting the employer from timely taking the deposition of the witness Kerby. We reverse and remand for further proceedings.
I
The facts can be summarized as follows. Claimant Madison, a male timber worker, has lived in New Meadows, Idaho, his entire life, except for 2 1/2 years when he was in the armed forces. The chief industry in the area is logging. Claimant graduated from the local high school in 1942. He has no further formal education. Besides logging, his only work experience has been manual labor on cattle ranches. He received no applicable technical training while in the armed sérvices in the mid-1940’s.
Since beginning work with J.I. Morgan, Inc. (employer) in 1951, claimant has been a timber faller, a job involving falling trees, cutting off the limbs, and measuring and bucking the fallen timber into log lengths. Claimant’s work has been seasonal, consisting of 40-hour work weeks for approximately 6V2 months each year.
On October 28, 1983, the industrial accident relevant to these proceedings occurred. Claimant’s left knee, left hip, left arm, back, and right ulnar nerve were injured when a snag fell on him, striking him in the mid-back region and pinning him underneath. Dr. Bills, an orthopedic surgeon practicing in Ontario, Oregon, surgically set claimant’s hip.
Sometime prior to mid-April, 1984, when claimant’s condition had improved to the point that he might be re-employable, Dr. Bills reviewed written jobsite evaluations for three possible positions with employer. *142The evaluations came from Bill Jordan, a consultant for the Industrial Commission’s Rehabilitation Division. One evaluation was for the position of “landing man,” an individual who, working on relatively level ground, unhooks cables from logs and limbs them. Use of a 25-pound chain saw was required. At that time Dr- Bills approved that job for claimant “with modifications.” However, sometime later he explained that those modifications included a 10-pound lifting restriction which essentially eliminated the “landing man” job from consideration. The second job, “sawyer/logger,” was the position claimant held when injured. Dr. Bills did not approve this position. The third job was as a “road crew worker,” which also involved the use of a 25-pound chain saw to cut brush, fall and limb trees. Dr. Bills did not sign the approval form.
After reviewing the jobsite evaluations in April, 1984, Dr. Bills did not see claimant again until November, 1984. At that time, in addition to the 10-pound weight restriction, he indicated that claimant should only occasionally bend, twist and squat, and should not be exposed to unprotected heights or excessive vibration. (At the time of his deposition in March, 1986, Dr. Bills had further added the condition that the maximum time claimant should spend on his feet at any one time was one hour, with five- to ten-minute rest periods in between, and that claimant should not walk on rough ground or jump down from heights.)
At a prehearing deposition taken by the employer on March 25, 1986, Bill Jordan, the Industrial Commission’s rehabilitation consultant, testified that the employer had informed Jordan that it would re-employ claimant as a landing man, as a sawyer, or as a road crew worker if claimant were able to do the job. As the date approached for claimant to return to work (approximately June, 1984), however, claimant objected to returning and did not seek work, “explainpng] that he is not sure that he would be able to return to the woods at all to work.” After his industrial accident, claimant did not seek any work with any employer until spring of 1986. Thereafter, each of claimant’s applications indicated a 10-pound lifting restriction. He did not obtain any employment.1
The hearing on Madison’s claim was held on June 30, 1986. As part of the preliminary matters, the post hearing submission of further depositions was discussed. Referring to Rule IX of the Industrial Commission’s Revised Rules of Practice and Procedure, the referee acknowledged that further depositions would be taken and submitted by both parties after the hearing. Rule IX(c) specifically permits that procedure, stating in part, “Following a hearing the record shall remain open for the submission of evidence by deposition for the following periods: all depositions to be submitted on behalf of a claimant shall be taken within 28 days following the date of hearing; all depositions to be submitted on behalf of a defendant shall be taken no later than 49 days following the conclusion of the hearing....”2
*143The record discloses the following discussion regarding Rule IX and the taking of additional post hearing depositions by the parties:
“REFEREE: Claimant will be submitting the depositions, after the hearing, of Dr. Ochs, Dr. Fellman and Polly Peterson. Defendants surety and employer possibly will submit the deposition of Dr. Corbin, possibly also the depositions of three representatives of prospective or possibly future employers of claimant, Miss Trahan, Miss Dobson, and someone at The Merc in McCall.
“REFEREE: Surety and employer also may submit the deposition of Mr. William Jordan of the Commission’s Rehabilitation Division and Dr. Bills?
“MR. STEGNER: That’s correct.
“REFEREE: And as I advised everyone before we went on the record, Revised Rule Roman numeral IX of the Commission’s Rules of Practice and Procedure now provides that all depositions on behalf of claimant must be taken within 28 days of today’s date, and that all depositions on behalf of defendants must be taken within 49 days.... ”
“All parties are advised to make sure that if you see a problem coming up, you get prior approval through a motion or stipulation and an order from the Commission before scheduling something outside that time period, or you risk not having those depositions being admitted except, of course, for rebuttal testimony, which has to be done on motion also.”
The Special Indemnity Fund also indicated that it might depose Dr. Droge, Dr. Nokes, Dr. Jack Long, and the three employers’ representatives mentioned above, i.e., Miss Trahan, Miss Dobson, and someone at The Merc in McCall.
After these preliminary matters, a short hearing was held. Claimant Madison presented no witnesses except his own testimony. Mr. Will Kerby, president of J.I. Morgan, Inc., and Mr. Caryl Fausett, office manager for J.I. Morgan, Inc., testified for defendants employer and surety. No other witnesses testified at the oral hearing conducted on June 30, 1986.
Thereafter, on July 23, 1986, as contemplated and discussed at the beginning of the June 30th hearing, the claimant took the deposition of Polly Peterson, a private vocational rehabilitation specialist. Claimant had hired her some nine months before the hearing to evaluate his condition relative to his employability. She had obtained a history and administered a general aptitude test in September of 1985. She also had reviewed the bulk of claimant’s medical history. She found claimant to have “quite a few real significant problem areas” in his vocational ability, including low intellectual capacity and manual dexterity scores. Claimant’s age was also a very significant factor operating against him, and he had very few skills transferable outside the logging industry. Ultimately, she testified in her post hearing deposition that she believed it was more probable than not that claimant was totally and permanently disabled.
After Polly Peterson’s post hearing deposition was taken on July 23,1986, employer timely noticed the taking of Kerby’s deposition for August 11, 1986. Claimant filed a motion for a protective order prohibiting employer from deposing Kerby. Kerby had previously testified at the hearing. Employer intended to elicit information from Kerby establishing that, subsequent to the hearing, employer offered claimant acceptable employment which was compatible with his physical limitations, but claimant declined to accept the employment. After a telephone hearing and the submission of written memoranda, the referee granted the claimant’s motion prohibiting the employer from taking Kerby’s deposition. The referee stated that Rule IX gave her discretion to determine whether or not to *144permit parties to submit post hearing deposition evidence.
One of the errors asserted on appeal is that the referee’s refusal to permit the taking of Kerby’s deposition violated employer’s right to a fair hearing. The employer points out the significance of this error by referring to the post hearing deposition of claimant’s witness, Polly Peterson, which the referee relied on in finding claimant to be totally disabled. In that deposition Peterson was asked, if she had been aware of the job offer about which Kerby would have testified, “Would you then change your opinion as to whether or not he was totally and permanently disabled?” She answered, “yes.” The referee, in her findings of fact, expressly relied on Polly Peterson’s post hearing deposition testimony, specifically finding it to be “more persuasive” than the testimony of Mr. Jordan, the Industrial Commission’s Rehabilitation Division consultant.
II
Although the employer raises several issues, we find the procedural issue, the refusal to permit the deposition testimony of witness Kerby to be taken, to be dispositive of this appeal, and we reverse.
Industrial Commission Rule IX(c) specifically provides that, “Following a hearing the record shall remain open for the submission of evidence by deposition for the following periods: .... ” This Court has held on many occasions that the word “shall” denotes a mandatory, not a discretionary act. Gilbert v. Moore, 108 Idaho 165, 169, 697 P.2d 1179, 1183 (1985) (“The word shall, when used in a statute, is mandatory.”); Pierce v. Vialpando, 78 Idaho 274, 301 P.2d 1099 (1956); Hollingsworth v. Koelsch, 76 Idaho 203, 280 P.2d 415 (1955), reh’g denied 1955; Munroe v. Sullivan Mining Co., 69 Idaho 348, 207 P.2d 547 (1949); State ex rel. Sweeley v. Braun, 62 Idaho 258, 110 P.2d 835 (1941). The referee and the commission erred when they precluded the taking of Kerby’s deposition. Ironically, in the preliminary proceedings just prior to commencing the hearing on June 30, 1986, the referee acknowledged the right of the parties to submit post hearing deposition testimony. The only condition mentioned in the referee’s statement concerning the parties’ right to take post hearing depositions was the time limits within which those depositions had to be taken. The referee stated:
“REFEREE: And as I advised everyone before we went on the record, Revised Rule Roman numeral IX of the Commission’s Rules of Practice and Procedure now provides that all depositions on behalf of claimant must be taken within 28 days of today’s date, and that all depositions on behalf of defendants must be taken within 49 days.... ”
“All parties are advised to make sure that if you see a problem coming up, you get prior approval through a motion or stipulation and an order from the Commission before scheduling something outside that time period, or you risk not having those depositions being admitted except, of course, for rebuttal testimony, which has to be done on motion also.”
The employer noticed Kerby’s deposition for August 11, 1986, which was well within 49 days of the June 30, 1986, hearing date. Under the clear mandatory wording of Rule IX(c), the employer should have been permitted to take Kerby’s deposition, and the referee’s protective order, granting the claimant’s motion to preclude the employer from taking and submitting Kerby’s deposition, was clear legal error.3 Moon v. Investment Board, 97 Idaho 595, 596, 548 P.2d 861, 862 (1976) (“where a statute or constitutional provision is plain, clear, and unambiguous, it ‘speaks for itself and must be given the interpretation the language clearly implies.’ ”).
We reverse the decision of the referee and the commission which granted the pro*145tective order; we set aside the commission’s final decision and order in this matter; and we remand with directions that the hearing be reopened to permit the employer to take the deposition of witness Kerby for submission to the commission pursuant to Rule IX(c). Thereafter, the commission shall make new findings of fact and conclusions of law based upon all the evidence in the record then before the commission. In view of our action remanding this matter for further proceedings and new findings, conclusion and order, the other issues raised by appellant, which relate primarily to the commission’s decision which has now been set aside, are rendered moot.
Reversed and remanded for further proceedings. Cost to appellant. No attorney fees on appeal.
SHEPARD, C.J., and JOHNSON, J., concur.. In late August, 1985, claimant had applied for benefits from employer’s retirement program, and when he turned age 62 those benefits began. Claimant was also receiving Social Security disability benefits which apparently also converted to retirement benefits at age 62. Claimant was receiving both types of retirement benefits at the time of the hearing on June 30, 1986.
. The entire Rule IX reads as follows:
"IX
"Presentation of Evidence
"(a) Parties may stipulate the facts in writing and the Commission may make its order or award thereon.
"(b) The testimony of any witness may be presented by deposition, provided that the party offering the deposition testimony provides reasonable notice prior to the taking of the deposition that the deposition may be used for testimonial purposes. The deposition testimony of any witness may also be presented by agreement of the parties. Absent such notice or agreement, a deposition may be used only to the extent allowed by the Idaho Rules of Civil Procedure.
“(c) Following a hearing the record shall remain open for the submission of evidence by deposition for the following periods: all depositions to be submitted on behalf of a claimant shall be taken within 28 days following the date of hearing; all depositions to be submitted on behalf of a defendant shall be taken no later than 49 days following the conclusion of the hearing; rebuttal evidence *143may be submitted by any party upon motion accompanied by a showing of the necessity for the presentation of such evidence. The Commission shall have the power to alter the time limits contained in this rule upon motion by showing a compelling reason for such modification. (New)”
. Our decision today is similar to our recent decision in Hanson v. BCB, Inc., 114 Idaho 131, 754 P.2d 444 (1988). In that case we reversed a decision of the Industrial Commission and ordered it to reconsider the case after excluding certain irrelevant evidence. In this case we are reversing the Industrial Commission and ordering that it reconsider this case with certain relevant evidence included.