What is the liability of a specialized employee (Ajir Khass) for accidental damage?

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A specialized employee, hired for a fixed period, bears no liability (dhaman) for damage unless the damage results from transgression (ta'addi). This ruling is held by Ahmad (in one narration by Mahanna), Malik, and Abu Hanifa and his companions. The evidence for this position is that the employee's labor itself is not guaranteed by him; therefore, what is damaged through the use of that labor is not his responsibility, analogous to the status of a laundry worker (qassar) or in analogy to blood money (qisas) and the cutting of a thief's hand. Furthermore, the specialized employee acts as a deputy (na'ib) for the owner in utilizing his services as directed, thus incurring no liability without transgression, similar to an agent (wakil) or a capital partner (mudharib). Specific examples support this: if a man ordered his servant to weigh grain for another man, and a unit of measure (rattl) fell and broke, the servant is not liable; similarly, if a man was hired to draw water and broke the water jar, or if a man was hired to plow with an ox and the plow broke, there is no liability.