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.