Keep the legacy M2001 useful—or replace it intelligently.
A technical resource for facilities maintaining M2001 ultrapure cleanroom foggers: archival specifications, inspection priorities, documentation recovery, safety context and a structured path to current Applied Physics equipment.
Three decisions determine the next move
The M2001 should not be treated as a generic fog machine. Before operating, repairing or replacing it, determine the exact unit revision, present mechanical condition and actual airflow-study requirement.
1. Identify the unit
Photograph the nameplate, controls, hose connection, dewar, boiler, power label and any serial or revision information.
2. Establish condition
Check for corrosion, damaged wiring, compromised hoses, missing relief features, altered components and evidence of previous repair.
3. Define the study
Document room size, desired visibility distance, runtime, hose layout, operating water and whether LN₂ handling remains acceptable.
What published historical descriptions consistently say
Archival product descriptions identify the M2001 as a full-size, high-purity airflow-visualization fogger that combined water vapor with liquid nitrogen to form a visible, low-residue fog. Published descriptions commonly cite approximately 45 minutes of operation, a roughly 3 µm droplet diameter, a 2.5 m flexible hose and an extendable wand assembly.
Why Applied Physics publishes this resource
Applied Physics manufactures current ultrasonic and LN₂ airflow-visualization systems. The goal of this site is to preserve useful M2001 search and support information while giving facility teams a direct route to a current manufacturer when legacy documentation, serviceability or performance no longer meets the study.
This site does not claim that Applied Physics originally manufactured the M2001.
Use the fastest defensible path
Need specifications?
Review the archival table and record every difference between the published profile and your actual unit.
Unit does not operate?
Use the troubleshooting page as a triage framework—not as authorization to bypass interlocks or open energized equipment.
Need a manual?
Submit photographs and identifiers first so the correct revision can be pursued instead of circulating an unverified PDF.
Considering replacement?
Compare required output, duration, fog purity, hose configuration, room size and consumables—not just model age.
Practical answers
Did Applied Physics manufacture the M2001?
This resource does not make that claim. Archival descriptions identify the M2001 as an MSP Corporation product distributed through other cleanroom-equipment channels. Applied Physics publishes this support and replacement-planning resource as a current cleanroom-fogger manufacturer.
Can I operate an M2001 without the original manual?
That is not recommended. Obtain or verify revision-specific operating information, inspect the unit, confirm the electrical rating and complete site cryogenic and electrical safety reviews before use.
Is the AP35 a direct M2001 replacement?
No current model should be treated as a drop-in replacement without an application review. The AP35 is a current passive/dewar-style LN₂ option worth evaluating, while other applications may fit a self-pressurized LN₂ or ultrasonic system.
Do not select a replacement from the model name alone.
Applied Physics can compare the existing unit, test objective, required fog output, runtime, room size, delivery hose and facility constraints before recommending a current ultrasonic or LN₂ platform.
Request a current-equipment evaluation