OSHA is proposing to add two PortaCount® quantitative fit-testing protocols to its Respiratory Protection Standard (29 CFR 1910.134); the proposed protocols would apply to employers in general industry, shipyard employment, and the construction industry. The first of the two proposed protocols consists of the eight fit-testing exercises described in Part I.A.14 of Appendix A of the Respiratory Protection Standard, except each exercise would last 30 seconds instead of the currently required 60 seconds.\1\ The second proposed protocol would eliminate two of the eight fit-testing exercises, and each of the remaining six exercises would last 40 seconds; in addition, this proposed protocol would increase the current minimum pass-fail fit-testing criterion from a fit factor of 100 to 200 for half masks, and from 500 to 1,000 for full facepieces.