The classification standard is the easy part. On a US cleanroom project, what decides the schedule is everything that has to be accepted by a US authority before the room can run.
Where US cleanroom projects actually slip
Imported process equipment cannot be energised until an NRTL field evaluation is done — and that evaluation must happen after installation at the final location, so it lands between mechanical completion and start-up.
Occupancy classification changes. Hazardous production materials can move the building into a different classification, which changes fire separation, egress, construction type and sprinkler design — a decision that is very hard to unwind late.
Qualification documentation gets retrofitted. Owners and auditors expect commissioning documented as IQ/OQ with traceable test data, not a certificate at handover. Building that path into the subcontracts afterwards rarely convinces anyone.
What we deliver
Cleanroom envelope
Wall and ceiling systems, flooring, pass-throughs, airlocks and gowning — built to the classification and the pressure cascade.
Cleanroom HVAC
Air handling, HEPA filtration, pressure cascade, temperature and humidity control, specified for 480 V / 60 Hz from the start.
Process utilities
DI water, compressed air, process gases, vacuum, chemical delivery and drainage, with the materials the process actually requires.
Building shell and fit-out
New build or retrofit of an existing building, including the structural and fire-protection work the classification drives.
Equipment approval coordination
NRTL field-evaluation route under NFPA 790/791, vendor documentation secured before payment.
Commissioning and IQ/OQ support
Documented testing with traceable data, aligned with the owner's validation plan.
ISO 14644 is the same here — the acceptance is not
Air change rates, filter selection, pressure cascade and recovery testing transfer directly from an Asian or European project. If your team has built ISO 7 or ISO 8 space before, that knowledge is good anywhere.
What changes is approval. The National Electrical Code requires listed equipment to be installed per its listing (NEC 110.3(B)), and the 2023 edition requires non-listed equipment to be evaluated to provide equivalent safety. A CE or CCC mark does not satisfy this.
The route is a field evaluation by an NRTL or field evaluation body under NFPA 790 / NFPA 791 — site-specific, one unit at a time, and only after the equipment is installed where it will run. On a twelve-machine line that is twelve evaluations sitting at the end of the programme.
We run a free pre-shipment review of an imported equipment list: the likely approval path per item, the vendor documents to secure before payment, 50 Hz exposure, and where each item lands on the schedule.
Pressure equipment and piping
Most US jurisdictions adopt the ASME Boiler and Pressure Vessel Code, and process piping is generally designed and fabricated to ASME B31.3. A vessel arriving with only a PED, GB or other foreign stamp is slow and expensive to get accepted after the fact, because the remedy runs through the jurisdiction rather than through a site repair.
Confirm the requirement with the specific jurisdiction and your insurer before the purchase order is placed. This applies to autoclaves, receivers, accumulators and any skid-mounted vessel inside an imported package.
60 Hz changes the air handling
US industrial supply is typically 480 V / 60 Hz. A fan or pump built for 50 Hz runs about 20% faster here — flow rises, power draw rises roughly as the cube of speed, and the noise and vibration signature changes. In a cleanroom, where the air handling is the room, that is a design change, not an electrical detail.
Specify the air handling for 60 Hz from the start, and convert only the process equipment that genuinely cannot be re-specified.
What we do and what we do not
We are a contractor. We build the facility, document the commissioning as IQ/OQ with traceable data, and coordinate the equipment approval route.
We do not perform process validation (PQ), issue certifications, or act as a notified body or NRTL — those sit with the owner and the accredited bodies. Being precise about this early is what keeps a qualification plan credible.
Special inspections under IBC Chapter 17 are employed by the owner — the code expressly excludes the contractor — so budget them on the owner side.
Who we are
CTECP has delivered turnkey ISO 14644 cleanrooms for electronics and precision manufacturing clients since 2016, and works in the United States through CTECP INC — Houston and Dallas, Texas, and Greenville, South Carolina.
Our specific value on these projects is the crossing: taking an equipment list and an engineering package produced in China or Europe and getting it through US code acceptance without discovering the problems at start-up. Project management runs in English · Español · 中文.
Frequently asked questions
Do you build GMP cleanrooms in the United States?
Yes. CTECP INC delivers ISO 14644 classified and GMP-grade cleanrooms as design-build, covering the envelope, cleanroom HVAC, process utilities and the building shell, from Houston, Dallas and Greenville, South Carolina.
Can we install cleanroom equipment imported from China or Europe?
Usually yes, but it has to be approved. Equipment carrying CE or CCC marks is not listed under the US National Electrical Code and typically needs a field evaluation by an NRTL under NFPA 790/791, performed after installation at its final location. Start that during fabrication, not after delivery.
Do imported pressure vessels need an ASME stamp?
Most US jurisdictions adopt the ASME Boiler and Pressure Vessel Code. A vessel without a recognised code stamp is difficult and slow to get accepted after arrival, so confirm the requirement with the jurisdiction and your insurer before the purchase order is placed.
Do you perform validation?
We document commissioning as IQ/OQ with traceable test data and align it with the owner's validation plan. We do not perform process validation (PQ) or act as a certifying body — those sit with the owner and accredited bodies.
Can you retrofit a cleanroom into an existing building?
Yes. Check incoming electrical service capacity, slab loading, clear height and whether the occupancy classification changes before signing — those three decide whether a retrofit is cheaper than new build.
How do we start?
Send the classification, approximate area, process utilities required and the equipment origin. Written reply within two business days, at no cost. Call +1 904 788 3028.