Laminar Flow Hood Inspection & Certification

Regulatory Guidance / Test Methods:

We offer testing, certification, and maintenance of Laminar Flow Hoods. We certify HLFs to meet IEST-RP-CC-002.4, and manufacturer’s standards. Our reports are supplied electronically same day.

HLF tests should be conducted whenever units are installed, moved, or following any significant maintenance.

Primary Services

Ensures that the air in the work area is unidirectional and performing as intended, preventing contamination incidents.
Documents leakage or defects and ensures HEPA filters for cleanroom provide the required filtration.

Additional Services

We can repair any faulty equipment
Replace any faulty / non-fixable HEPA filters.
Performed in accordance with ISO14644-1 and reports the amount of particulate, if any, in the workzone.
Determines if any bacterial and fungal contamination is present.

Why choose Keystone

Keystone has tested and certified controlled environments for over 25 years. When we started Keystone we serviced Virginia and the surrounding areas. Today we service the east coast. Our team has over 100 collective years of experience in the industry, serving over 200 pharmaceutical, university, research, and advanced manufacturing clients.

We test, certify, and service all controlled environments, including cleanrooms, biosafety cabinets, fume hoods, and isolators. We provide biosafety cabinets, cleanbenches and fume hood reports the same-day, and turnaround electronic cleanroom reports in two weeks. For any emergency, we can get a technician to your site quickly.

We are proudly 100% founder and employee owned. Keystone is a certified minority business enterprise.


25 years of company history


Highly trained technicians (average 10-year tenure)

Report Turnaround

We prioritize prompt delivery of reports.


We take emergency calls seriously. We can get technicians on-site quickly


Founder and employee-owned. Certified minority business enterprise

Our Locations

We are a regional service provider

As a regional service provider, Keystone provides testing and certification services across the midatlantic region and east coast.