15. A worker on its 7.5-hour workday is in contact with N,N-dimethylformamide for 6 hours and 25 minutes. The mean concentration measured during this time is 20.5 mg/m3. Determine the value of the daily exposure to this substance (DE). Assess the conditions to which the worker is exposed if the TLV for the N,N dimethylformamide is 15mg/m3. Would it be necessary to carry out any measures to prevent adverse effects on worker's health? In case that it is necessary, which measures could be taken