What are Interim Life Safety Measures (ILSM) in healthcare?
Interim Life Safety Measures (ILSM) are the documented, compensatory actions a healthcare facility takes when construction activity or a Life Safety Code deficiency temporarily degrades the building’s normal fire and life safety protections. Think of ILSM as the bridge between “the building isn’t fully protected right now” and “patients, staff, and visitors are still safe” — a formal set of extra precautions that stays in force until full protection is restored.
What “interim” really means
A hospital’s life safety systems — compartmentation, egress, fire alarm, detection, suppression — are designed to work as an integrated whole. When construction opens up a smoke barrier, or a deficiency takes a sprinkler zone offline, that integration breaks. ILSM compensates with human and procedural measures: more eyes (surveillance), more equipment, more training, more drills, temporary equivalent systems. They don’t replace the engineered systems — they hold the risk down until the engineered systems are back.
The two triggers
- Construction projects that affect life safety features — egress paths, fire/smoke barriers, alarm, detection, or suppression systems.
- Life Safety Code deficiencies that can’t be corrected immediately — the deficiency is documented (often in the e-Statement of Conditions) and ILSM covers the gap.
Each trigger gets a case-by-case ILSM assessment: which protections are degraded, which of the standard measures apply, who implements them, and how they’re documented. Blanket ILSM (“we always do all of them”) and missing ILSM (“we didn’t think this project needed it”) both fail surveys — the assessment is the evidence that someone actually thought it through.
ILSM vs. the fire safety plan vs. ICRA
Your fire safety plan is the permanent program — RACE/PASS, alarm response, evacuation. ILSM is the temporary overlay on that plan for a specific degradation. ICRA is the parallel program protecting against infection risk from the same construction. One project, three programs, one coordinated story — that’s what surveyors expect to see.
New to the ILSM framework?
Start with the Joint Commission’s stance on ILSM during construction, then read how ICRA and ILSM divide the work on one project.
FAQ
Are ILSM a Joint Commission requirement or a best practice?
A requirement — standard LS.01.02.01, with elements of performance surveyors score directly.
Do ILSM apply to the whole building or just the affected area?
The measures apply where the assessment says they apply — typically the affected area plus adjacent spaces whose egress, alarm, or compartmentation is impacted. The assessment defines the boundary.
What’s the difference between ILSM and a fire watch?
A fire watch is one possible ILSM-level response — the most intensive one, used when alarm or suppression is out beyond the 4-hour/10-hour thresholds. ILSM is the full framework; fire watch is its heaviest tool.