This method covers test methods and selection criteria for prequalification of sealers for protecting new concrete or prolonging the life of sound in-service concrete used in highway structures. Sealer testing and evaluation for routine and job site product quality assurance, field performance, and reapplication are provided in AASHTO R 94. Sealers are divided into two basic types: coatings, which remain on the surface; and penetrants, which penetrate into the concrete to some measurable depth and do not substantially change the appearance of the concrete. This standard was formerly designated as provisional standard TP 96.