A process in which an at least partially delignified pulp fiber web having a Kappa number of less than about 130 is treated with an aqueous endothermic fire retardant solution having a pH of about 10 or less. The treated pulp fiber web has a near neutral pH of from about 5 to about 9, and is treated with at least about 20 lbs of endothermic fire retardants per ton of the pulp fiber web, with at least about 5% of the total amount of endothermic fire retardants being added at a point prior to when the pulp fiber web is formed. Also a fire resistant pulp fiber web having a near neutral pH.