What is a potential ignition hazard when using a reciprocating saw on magnesium alloy?

When using a reciprocating saw on magnesium alloy, friction can create sparks, which is a significant ignition hazard. Magnesium is highly flammable, especially when it is in the form of fine particles generated by cutting or grinding. The heat and sparks produced by the saw's blade making contact with the magnesium can ignite the metal, leading to potentially dangerous fires.

While the saw may indeed overheat, and airborne dust can pose other safety risks, it is the friction and subsequent sparks that directly create a risk of ignition. Fuel spills can also be hazardous in a general context but are not specifically related to the use of the saw on magnesium alloy. Thus, the generation of sparks from friction stands out as the primary hazard in this scenario.