A fabric for a thermal protective application includes: 5-40 weight % PBI-p fiber and the balance being conventional fibers, where the fabric has equal or better flame-resistant and/or heat-resistant properties, and a fabric weight less than an equivalent fabric made with a like amount of PBI-s fiber in place of the PBI-p fibers. The fabric for a thermal protective application includes: 5-40 weight % of a blend of PBI-p fiber and PBI-s fiber, and the balance being conventional fibers, where the fabric has equal or better flame-resistant and/or heat-resistant properties and a fabric weight less than an equivalent fabric made with a like amount of PBI-s fiber in place of the PBI-p fibers.