Abstract: A modular respiratory protection system comprises a frame defining an opening configured to expose a portion of a user's head. A blower is configured to draw air through an air filter and through a portion of the frame. A head protection element is releasably coupled to the frame and the head protection element is configured to cover the opening.

Abstract: The described embodiments relate to systems, methods and computer readable media for bidding on service requests, that involves receiving a service request, wherein the service request comprises a user identifier, a location and a destination; generating a bid request corresponding to the service request; receiving a plurality of bids, wherein each bid comprises a service provider identifier for a corresponding service provider, a cost and a service time; transmitting the plurality of bids; and receiving a selected bid of the plurality of bids.