A mine is being developed by bord and pillar method with a gallery size of $4.8 \, \text{m} \times 2.4 \, \text{m}$. The mine operates in 3 shifts per day and 6 faces are blasted per shift. The average pull per round of blast is $1.2 \, \text{m}$ and the bulk density of coal is $1.4 \, \text{t/m}^3$. If the OMS is $2.5$, then the average manpower deployed in the development section per shift is ______.