The present invention is directed to detergent compositions that not only have superior viscosity, spreadability, and clarity properties but also do not cause significant irritation to the skin and eyes. Based on the indication of the location provided by a location tracking system, environmental information is obtained regarding at least one environmental condition of an environment in which the locate device is used, and logged into local memory of the locate device. The plurality of independent signalling light sources emit at least one light flash in response to a control signal received from the control module. A plurality of electrospray devices can be used in the form of an array of miniaturized separate electrospray devices for the purpose of generating multiple electrospray plumes from multiple nozzles for the same fluid for analysis. For example, a low density thin wall polyethylene valve head can be supported by a trapped air pocket to reduce leakage, permit some flexibility, and avoid permanent deformation.