The electromagnetic wave contain both electric and magnetic field. Light is an electromagnetic wave wich contain magnectic field . Thus there should be deflection in compus and dammage for electric equpments ? Why this is not happening?

Light is an electromagnetic wave and which is a transverse in nature. As the electric field (E), magnetic field (B) and the propagation vector (K) are perpendicular to each other. All these components will lie in a plane and balancing to each other. Therefore, there is no deflection in compass.