The dispositive issue in this administrative appeal is whether injured state employees may elect to calculate their benefits in accordance with the traditional workers’ compensation benefits established by General Statutes § 31-307 rather than by the special duty benefits established by General Statutes § 5-142 (a).1 A workers’ compensation commissioner *723determined that the plaintiff, Mary A. Jones (claimant), had suffered a compensable work related injury in the course of her state duty that would have entitled her to receive her full salary under § 5-142 (a). Because an alternate calculation of her benefits for her temporary total incapacity in accordance with § 31-307 would allow her a substantially higher compensation rate, the commissioner held that she could recover this larger amount. On appeal by the defendant, Mansfield Training School (state), the compensation review division concluded, to the contrary, that the remedy provided by § 5-142 (a) was exclusive and precluded the recovery of any other workers’ compensation benefits. The *724claimant appealed to the Appellate Court, and we transferred her appeal to this court in accordance with Practice Book § 4023. We reverse.
The facts were stipulated. As a result of an attack by one of the residents of the Mansfield Training School, the claimant, an employee of the school, sustained an injury to her right knee and left thumb that left her temporarily totally incapacitated. If calculated in accordance with § 5-142 (a), her weekly compensation rate would be $310.15, because that was her full weekly salary at the time of her injury. If calculated in accordance with § 31-307, her weekly compensation rate would be $462.86, because she had performed substantial overtime work increasing her average weekly earnings to $694.26 during the twenty-six weeks prior to her injury.2
The claimant appeals from the determination of the compensation review division limiting her compensation benefit to that established by § 5-142 (a). Her principal argument is that she has a statutory right to elect benefits pursuant to § 31-307.3 Alternatively, she con*725tends that her § 5-142 (a) benefits should be construed to include overtime income. Because we accept the first of these arguments, we do not reach the second one.
As the compensation review division noted in its opinion, our legislature enacted the predecessor statute to § 5-142 (a) in 1939 in order to provide enhanced benefits by way of disability compensation for employees injured while engaged in special state service.4 The class of employees eligible for these benefits is those who “in the daily course of performing their duties, work in an atmosphere sometimes charged with emotion and stress, and face the possibility of confrontations with inmates, patients or arrestees, which confrontations often result in violence.” Lucarelli v. State, 16 Conn. App. 65, 69, 546 A.2d 940 (1988). If injured under the circumstances prescribed in the statute, this class of state employees is entitled to disability compensation based upon the employee’s full salary, rather than upon a percentage of his or her weekly earnings, the normal workers’ compensation standard. Ordinarily, therefore, the remedy provided by § 5-142 (a) will be advantageous to the injured employee. The legislature, in its various reenactments of General Statutes (Sup. 1939) § 78e, has steadfastly manifested its intention to make these benefits a generous source of compensation for its designated beneficiaries.
*726The issue before us is whether the legislature intended to make the special benefit conferred by § 5-142 (a) the exclusive remedy for an injured worker even in the unusual situation in which an alternate calculation of workers’ compensation benefits would provide greater financial relief. “In order to ascertain and give effect to the apparent intent of the legislature, we must examine the language of the statute in light of the purpose that it was designed to achieve. Mahoney v. Lensink, 213 Conn. 548, 563, 569 A.2d 518 (1990); Beloff v. Progressive Casualty Ins. Co., 203 Conn. 45, 54-55, 523 A.2d 477 (1987); Rhodes v. Hartford, 201 Conn. 89, 93, 513 A.2d 124 (1986).” Szudora v. Fairfield, 214 Conn. 552, 557, 573 A.2d 1 (1990). In implementing the purpose of the statute, “[w]e must avoid a construction that fails to attain a rational and sensible result that bears directly on the purpose the legislature sought to achieve. Peck v. Jacquemin, 196 Conn. 53, 63-64, 491 A.2d 1043 (1985). If there are two possible interpretations of a statute, we will adopt the more reasonable construction over one that is unreasonable. State v. Uretek, Inc., 207 Conn. 706, 719, 543 A.2d 709 (1988); State v. Parmalee, 197 Conn. 158, 165, 496 A.2d 186 (1985).” Turner v. Turner, 219 Conn. 703, 713, 595 A.2d 297 (1991); Fairfield Plumbing & Heating Supply Corporation v. Kosa, 220 Conn. 643, 650-51, 600 A.2d 1 (1991).
The state points to three statutory provisions as indicative of a legislative intent to require injured employees to look to § 5-142 (a) in lieu of all other possible workers’ compensation benefits. Section 5-142 (a) itself states that a covered employee who has become totally incapacitated “shall continue to receive the full salary which he was receiving at the time of injury . . . .” (Emphasis added.) The subsection also states: “All other provisions of the workers’ compensation law not inconsistent herewith, including the specific indem*727nities and provisions for hearing and appeal, shall be available to any such state employee . . . .’’(Emphasis added.) Finally, General Statutes (Rev. to 1991) § 5-143 states: “Each state employee who sustains an injury arising out of and in the course of his employment, except as provided in section 5-142, shall be paid compensation in accordance with the provisions of the workers’ compensation act. . . .” (Emphasis added.)
We are not persuaded that the legislature’s use of the word “shall” demonstrates that the salary benefit provided by § 5-142 (a) precludes an injured worker from recourse to another workers’ compensation remedy. “[I]n the interpretation of statutes the word ‘shall’ may have a meaning that is directory rather than mandatory. Fidelity Trust Co. v. BVD Associates, 196 Conn. 270, 278, 492 A.2d 180 (1985). The test to be applied in determining whether a statute is mandatory or directory is whether the prescribed mode of action is the essence of the thing to be accomplished, or in other words, whether it relates to a matter of substance or a matter of convenience. International Brotherhood of Teamsters v. Shapiro, 138 Conn. 57, 68, 82 A.2d 345 (1951). If it is a matter of substance, the statutory provision is mandatory. State ex rel. Eastern Color Printing Co. v. Jenks, 150 Conn. 444, 451, 190 A.2d 591 (1963). If, however, the legislative provision is designed to secure order, system and dispatch in the proceedings, it is generally held to be directory, especially where the requirement is stated in affirmative terms unaccompanied by negative words. Winslow v. Zoning Board, 143 Conn. 381, 388, 122 A.2d 789 (1956). Such a statutory provision is one which prescribes what shall be done but does not invalidate action upon a failure to comply. Broadriver, Inc. v. Stamford, 158 Conn. 522, 529, 265 A.2d 75 (1969). Fidelity Trust Co. v. BVD Associates, supra, 278.” (Internal quotation marks omitted.) Statewide Grievance Committee v. Rozbicki, *728219 Conn. 473, 480-81, 595 A.2d 819 (1991); see also Beccia v. Waterbury, 185 Conn. 445, 460-61, 441 A.2d 131 (1981). The essence of § 5-142 (a) is to provide the enhanced benefit of a full salary to a state employee who has been injured within its purview. Without more, the legislature should not be deemed to have made that right exclusive.
The state buttresses its argument for exclusivity by pointing to the legislature’s express preservation, for injured § 5-142 (a) state employees, of only those “other provisions of the workers’ compensation law not inconsistent herewith, including the specific indemnities and provisions for hearing and appeal . . . .” This proviso fails, however, to define what the legislature deems “inconsistent.” The possibility that access to “specific indemnities” may afford further relief to injured state employees; see General Statutes § 31-308 (b); suggests that the legislature recognized that payment of a salary might not make an injured employee whole. In light of that recognition, we are not persuaded that the legislature, in assigning priority to § 5-142 (a) entitlements, manifested its intent to preclude an employee from recourse to § 31-307.
The same ambiguity inheres in the clause in § 5-143 entitling injured state employees to workers’ compensation benefits “except as provided in section 5-142.” Because this statute’s predecessor was enacted conjointly with the predecessor of § 5-142; see General Statutes (Sup. 1939) §§ 79e and 78e; and hence relates to the same area of the law, the two statutes necessarily must be interpreted as a unitary whole. “We are obligated ... to read statutes together when they relate to the same subject matter. Felia v. Westport, 214 Conn. 181, 187, 571 A.2d 89 (1990); In re Ralph M., 211 Conn. 289, 304-305, 559 A.2d 179 (1989).” Concerned Citizens of Sterling, Inc. v. Connecticut Siting Council, 215 Conn. 474, 482-83, 576 A.2d 510 (1990); *729see also State v. Carroll, 97 Conn. 598, 604, 117 A. 694 (1922). The “except” clause in § 5-143 therefore provides no specific enlightenment about legislative intent other than that contained in § 5-142 (a).
What is notable about the text of both §§ 5-142 (a) and 5-143 is that the legislature has repeatedly had the opportunity expressly to designate § 5-142 (a) benefits as an exclusive remedy. It has not chosen to do so. It did not use the express language of “exclusive remedy,” which appears elsewhere in our workers’ compensation law, for example in General Statutes § 31-293a, which provides that a right to workers’ compensation benefits for an injury caused by a negligent fellow worker “shall be the exclusive remedy of such injured employee or dependent and no action may be brought against such fellow employee unless such wrong was wilful or malicious or the action is based on the fellow employee’s negligence in the operation of a motor vehicle as defined in section 14-1.” See also General Statutes §§ 33-373 (f), 38a-148 (b). It did not, in the alternative, provide that, for state workers covered by § 5-142 (a), the state would not be otherwise liable to pay benefits. A similar formulation, in General Statutes § 31-284 (a),5 has been uniformly construed to make workers’ compensation the exclusive remedy and thereby to insulate employers from suits *730for damages by their employees for job related death or injury. See Sgueglia v. Milne Construction Co., 212 Conn. 427, 433, 562 A.2d 505 (1989).
Our reluctance to infer exclusivity of remedy from the ambiguous provisions of a remedial statute finds support, furthermore, in another case in which we concluded that workers are entitled to choose between different statutory measures providing compensation for on-the-job injuries. In Bakelaar v. West Haven, 193 Conn. 59, 66-69, 475 A.2d 283 (1984), we concluded that a municipal firefighter or police officer suffering from hypertension or heart disease could elect whether to proceed under General Statutes § 7-433c, which specifically addresses such a claim for benefits, or under chapter 568, the traditional workers’ compensation law. We there rejected the contention of the defendant city that the workers’ compensation statutes furnished the exclusive remedy for injuries arising out of and in the course of employment, even if the injuries claimed were compensable under § 7-433c. We concluded that the defendant city’s contention was inconsistent with the beneficial purpose of § 7-433c to provide enhanced eligibility for benefits to firefighters and police officers, “[notwithstanding any provision of chapter 568.”
Concededly, the governing statutes in Bakelaar were clearer than they are in this case. We are nonetheless persuaded that the legislature did not intend, sub silentio, to convert the special benefits conferred by § 5-142 (a) into an obstacle to the greater recovery under § 31-307 to which the claimant would otherwise be entitled because of her long record of overtime work. We may presume that the claimant worked overtime because such overtime service enabled her to increase her take-home pay and because the state, as her employer, determined that her overtime work benefit-ted the operations of the Mansfield Training School. Having acquiesced in this arrangement, the state would *731require strong justification now to deprive the claimant of benefits that she has earned. We conclude that the legislature has manifested no intent to visit such an injustice on this claimant.
The judgment is reversed and the case is remanded to the compensation review division with direction to reinstate the finding and award of the compensation commissioner.
In this opinion Shea and Callahan, Js., concurred.
General Statutes (Rev. to 1991) § 31-307 provides in relevant part: “compensation for total incapacity. If any injury for which compensation is provided under the provisions of this chapter results in total incapacity to work, there shall be paid to the injured employee a weekly compensation equal to sixty-six and two-thirds per cent of his average weekly earnings at the time of the injury; but the compensation shall in no case be more than the maximum weekly benefit rate set forth in section 31-309 for the year in which the injury occurred .... No employee entitled to compensation under this section shall receive less than twenty per cent of the maximum weekly compensation rate, as provided in section 31-309, provided *723such minimum payment shall not exceed eighty per cent of the employee’s average weekly wage, as determined under section 31-310; and such compensation shall not continue longer than the period of total incapacity. ...” This statute was amended by Public Acts 1991, No. 91-32, §§ 23, 41, effective July 1, 1991, and by No. 91-339, §§ 26, 55, effective October 1, 1991.
General Statutes (Rev. to 1991) § 5-142 provides in relevant part: “disability compensation, (a) If any member of . . . any correctional institution . . . or any employee of any juvenile detention home . . . sustains any injury while making an arrest or in the actual performance of such police duties or guard duties or fire duties or inspection duties, or . . . while attending or restraining an inmate of any such institution or as a result of being assaulted in the performance of his duty, the state shall pay all necessary medical and hospital expenses resulting from such injury. If total incapacity results from such injury, such person shall be removed from the active payroll the first day of incapacity, exclusive of the day of injury, and placed on an inactive payroll. He shall continue to receive the full salary which he was receiving at the time of injury subject to all salary benefits of active employees, including annual increments, and all salary adjustments, including salary deductions, required in the case of active employees, for a period of two hundred sixty weeks from the date of the beginning of such incapacity. Thereafter, such person shall be removed from the payroll and shall receive compensation at the rate of fifty per cent of the salary which he was receiving at the expiration of said two hundred sixty weeks so long as he remains so disabled .... All other provisions of the workers’ compensation law not inconsistent herewith, including the specific indemnities and provisions for hearing and appeal, shall be available to any such state employee or the dependents of such a deceased employee. . . .” This statute was amended, effective October 1, 1991, by Public Acts 1991, No. 91-339, §§ 40, 55.
Under General Statutes (Rev. to 1991) § 31-310, for the purposes of General Statutes § 31-307, “the average weekly wage shall be ascertained by dividing the total wages received by the injured worker from the employer in whose service he is injured during the twenty-six calendar weeks immediately preceding that during which he was injured, by the number of calendar weeks during which, or any portion of which, such worker was actually employed by such employer . . . .” This statute was amended, effective July 1, 1991, by Public Acts 1991, No. 91-32, §§ 28, 41, and No. 91-339, §§ 30, 55.
The claimant’s contention that she has a statutory right to election of remedies is buttressed by her assertion that a contrary construction of General Statutes § 5-142 (a) would violate her constitutional rights to equal protection of the laws under the fourteenth amendment to the United States constitution and article first, § 20, of the Connecticut constitution. Although the claimant briefed this issue in response to the state’s appeal to the compensation review division, the review division did not address it. The record does not indicate whether the claimant actively pursued her constitutional claim before the review division. In view of our disposition of the claimant’s appeal, we need not decide whether this issue is properly before us.
As enacted in 1939, General Statutes § 78e provided in relevant part: “DISABILITY COMPENSATION TO EMPLOYEES OF STATE POLICE AND STATE institutions. Each employee of the state police department or of any correctional or penal institution or of any institution for the care of persons afflicted with a mental disorder or a mental defect, in case of injury sustained while making an arrest or in pursuit of such purpose, or while attending or restraining an inmate of any such institution or sustained as a result of being assaulted while in the performance of his duty, shall not be removed from the payroll, except that, in the event of total disability, he shall be continued on the payroll for two hundred and sixty weeks and thereafter shall receive compensation at the rate of one-half the salary he was receiving at the time of the injury . . . .”
General Statutes (Rev. to 1991) § 31-284 (a) provides in relevant part: “BASIC RIGHTS AND LIABILITIES. CIVIL ACTION TO ENJOIN NONCOMPLYING EMPLOYER FROM ENTERING EMPLOYMENT CONTRACTS, (a) An employer shall not be liable to any action for damages on account of personal injury sustained by an employee arising out of and in the course of his employment or on account of death resulting from personal injury so sustained, but an employer shall secure compensation for his employees as follows, except that compensation shall not be paid when the personal injury has been caused by the wilful and serious misconduct of the injured employee or by his intoxication.” This statute was amended by Public Acts 1991, No. 91-32, §§ 7, 41, effective July 1, 1991, and No. 91-339, §§ 11, 55, effective January 1, 1992.