I want to clarify a confusing point in the seven-year old CMS S&C memo 07-18 issued April 20, 2007. This is a memo which CMS wanted to explain that corridor doors that are not fire-rated or used in a smoke compartment barrier are permitted to have gap clearances up to ½-inch in smoke compartments that are protected with sprinklers. In this memo they have conflicting points; the subject line of the memo stated: “Permitted Gaps in Corridor Doors and Doors in Smoke Barriers”, but in the content of the memo they say “This information does not apply to doors in smoke barriers, which have other requirements.”
Click on this link to access this CMS memo: https://www.cms.gov/Medicare/Provider-Enrollment-and-Certification/SurveyCertificationGenInfo/Policy-and-Memos-to-States-and-Regions-Items/CMS1198675.html?DLPage=1&DLFilter=07-18&DLSort=3&DLSortDir=ascending
To be clear, the maximum gap for the proper clearance of smoke compartment barrier doors is 1/8 inch; not ½ inch, and it is not dependent on whether or not the smoke compartment is sprinklered. Sections 18/220.127.116.11 of the 2000 LSC references section 8.3.4 of the same code and the Annex section of 18.104.22.168 says the maximum gap for smoke compartment barrier door clearances is 1/8 inch.
The CMS memo addressed corridor doors that are not fire-rated or located in a smoke compartment barrier. Corridor doors are those doors which separate a room or an area from the corridor. Can a corridor door also be a fire-rated door or a door in a smoke compartment barrier? Yes, certainly; and in those situations the more restrictive requirements must apply.
The bottom line: Doors in smoke compartment barriers must not have gap clearances that exceed 1/8 inch per the 2000 LSC. The CMS S&C memo 07-18 only applies to non-fire-rated corridor doors that are not located in a smoke compartment barrier.