87. During recess machines, beltings and lathes must be stopped, unless this be impossible owing to technical conditions or in cases where these machines, beltings, etc., serve for ventilation, drainage, lighting, etc. 88. The time of recess fixed by Section 86 is not included in the working hours. 89. The recess must take place not later than four hours after the beginning of the working day, and must continue not less than a half hour and not more than two hours. _Note._ Additional intermissions every three hours, and for not less than a half hour, must be allowed for working women nursing children. 90. The wage earners may use their free time at their own discretion. They shall be allowed during recess to leave the place of work. 91. In case the nature of the work is such that it requires a working day in excess of the normal, two or more shifts shall be engaged. 92. Where there are several shifts, each shift shall work the normal working hours; the change of shifts must take place during the time fixed by the rules of the internal management without interfering with the normal course of work. 93. As a general rule, work in excess of the normal hours (overtime work) shall not be permitted. 94. Overtime work may be permitted in the following exceptional cases: (_a_) Where the work is necessary for the prevention of a public calamity or in case the existence of the Soviet Government of the R. S. F. S. R. or human life is endangered; (_b_) An emergency, public work in relation to water supply, lighting, sewerage or transportation, in case of accident or extraordinary interruption of their regular operation; (_c_) When it is necessary to complete work which, owing to unforeseen or accidental delay due to technical condition of production, could not be completed during the normal working hours. If leaving the work uncompleted would cause damage to materials or machinery; (_d_) On repairs or renewal of machine parts or construction work, wherever necessary to prevent stoppage of work by a considerable number of wage earners. 95. In the case described in subdivision “_c_” of Section 94, overtime work is permissible only with the consent of the respective trade union. 96. For overtime work described in subdivision “_d_” of Section 94, permission must be obtained from the local labor inspector, in addition to the permit mentioned in the preceding section. 97. No females and no males under 18 years of age may do any overtime work. 98. The time spent on overtime work in the course of two consecutive days must not exceed four hours. 99. No overtime work shall be permitted to make up for a wage earner’s tardiness in reporting at his place of work. 100. All overtime work done by a wage earner, as well as the remuneration received by him for the same, must be recorded in his labor booklet.