A method comprises rendering a hydrocarbon industry servicing fluid biologically inert without using chemical biocides. One method of rendering a hydrocarbon industry servicing fluid biologically inert comprises irradiating at least one constituent of the servicing fluid to produce an irradiated fluid. Another method comprises irradiating a used hydrocarbon industry servicing fluid to produce a remediated fluid that is biologically inert. A fluid treatment system comprises an irradiation apparatus, inlet piping directing an untreated fluid into the irradiation apparatus, outlet piping directing an irradiated fluid out of the irradiation apparatus, and a connection to a hydrocarbon industry application.