A seller of specialized instruments (thin film deposition monitors, gas analyzers, leak detectors, gauges, and optical measurement products used in semiconductor cleanrooms and other manufacturing) asked which of these items its manufacturer-customers can buy tax-free with a manufacturing exemption certificate.

Plain-English summary

A seller of specialized measurement and detection instruments — thin film deposition controllers, residual gas analyzers, halogen and helium leak detectors, a field-portable gas chromatograph/mass spectrometer (HAPS), vacuum gauges, and optical semiconductor-process measurement tools (LES/OES, "Composer") — asked which of these items its manufacturer-customers could buy tax-free with a manufacturing exemption certificate under Sec. 151.318.

The Comptroller confirmed the general rule up front: Texas doesn't have a blanket exemption for environmental protection equipment, but manufacturers can still claim exemption on taxable items when the item is used in a way that qualifies under Sec. 151.318 — the seller must collect tax unless the manufacturer provides a properly completed exemption certificate, which the seller can then accept in good faith. The Comptroller then went item by item:

• Thin film deposition controllers/monitors — exempt, because they're used directly in manufacturing to make or cause a physical/chemical change in the product.
• Residual gas analyzers (RGA) — a semiconductor manufacturer can buy cleanroom equipment like this tax-free, and specifically, using it for quality control testing during manufacturing qualifies for exemption.
• Halogen leak detectors — exempt when a manufacturer of refrigeration/AC equipment uses one for quality control testing during manufacturing, but not exempt for a contractor installing or repairing HVAC systems in real property, since a service contractor isn't a manufacturer.
• Stationary/portable helium leak detectors — same pattern: exempt for a semiconductor manufacturer's cleanroom use or quality control testing, but not exempt for a repairman servicing vehicles or gas delivery/storage systems.
• HAPS gas chromatograph/mass spectrometer — exempt if a manufacturer uses it because it's necessary and essential to a pollution control process or to comply with public-health laws/rules — but not for an environmental investigator or clean-up services company, since they aren't manufacturers. (Separately, purchases by exempt government agencies like the EPA or the Texas Natural Resources Commission are exempt on their own government-purchaser basis, provable with a purchase voucher.)
• Inficon vacuum gauges — exempt for cleanroom use and quality control testing by a semiconductor manufacturer.
• LES/OES optical measurement products and the Composer gas-composition analyzer — exempt as cleanroom equipment a semiconductor manufacturer can buy tax-free.

The throughline across every item: the exemption tracks the buyer's status and use, not the equipment itself. The identical instrument can be tax-exempt in a manufacturer's hands and fully taxable in the hands of a service contractor, repairman, or investigator performing similar-looking but non-manufacturing work.

What this means for you

Sellers of precision instruments and detection equipment to manufacturers

Whether your product is exempt depends entirely on your customer's status (manufacturer vs. service provider) and how they use the item (in-process manufacturing, quality control, or pollution/public-health compliance vs. repair, inspection, or environmental cleanup services). Collect a properly completed exemption certificate from qualifying manufacturer-buyers and you can accept it in good faith without collecting tax.

Semiconductor and other manufacturers buying cleanroom/testing instruments

Cleanroom equipment, quality control test instruments, and pollution-control/compliance equipment used in your own manufacturing process generally qualify for the Sec. 151.318 exemption — give your supplier a proper exemption certificate.

Contractors, repairmen, and environmental service companies buying similar equipment

The same detectors and analyzers that are exempt for a manufacturer are taxable for you, because you aren't a manufacturer even if you use functionally similar equipment to inspect, repair, or investigate.

Accountants and tax professionals

A good multi-item reference for how Sec. 151.318's manufacturing exemption categories — direct production use, quality control, and pollution control/public-health compliance — apply consistently across a range of specialized scientific instruments, always gated by the buyer's manufacturer status.

Common questions

Q: Are cleanroom instruments (gas analyzers, leak detectors, gauges) automatically tax-exempt because they're used in a semiconductor cleanroom?
A: No — exemption depends on the buyer being a manufacturer using the equipment in manufacturing, quality control, or required pollution-control/public-health compliance, not on the equipment type alone.

Q: Can a contractor or repairman claim the manufacturing exemption on the same detectors a manufacturer buys tax-free?
A: No — a contractor installing/repairing HVAC systems, an environmental investigator, or a vehicle/gas-system repairman is not a manufacturer and cannot claim the exemption for this equipment.

Q: Are environmental government agencies exempt when buying this kind of equipment?
A: Yes — purchases by exempt federal or state government agencies (like the EPA or the Texas Natural Resources Commission) are exempt as government purchases, provable with a purchase voucher.

Q: Can I rely on this letter for my own equipment sales?
A: No. It's based on the specific facts submitted and can be relied on only by the taxpayer to whom it was issued; other facts, even if similar, may produce a different result.

Citations and references

Statutes and rules:

• Texas Tax Code Section 151.318 (manufacturing exemption, including quality control, pollution control, and public-health-compliance items)

Source

• STAR search: https://star.comptroller.texas.gov/search?doc_type_code=L&tax_type_code=SST
• Opinion: https://star.comptroller.texas.gov/view/9908617L

Original ruling text

August 6, 1999

Dear Mr. **:

Thank you for your letter concerning the sales tax exemption in Texas for
manufacturers who purchase qualifying manufacturing items.

Texas does not exempt sales of environmental protection equipment, but
manufacturers are able to claim exemption when purchasing taxable items used in
a manner qualifying for exemption under Texas Tax Code Section 151.318. Your
company is required to collect tax unless the manufacturer gives a properly
completed exemption certificate (enclosed). Your company may then accept the
exemption certificate in good faith and not collect sales tax. I have
addressed each of the items on your list in regards to whether the item could
be used in an exempt manner by a manufacturer.

Thin Film Deposition Controllers and Monitors

This equipment is used in placing a thin coating on many types of product.

Response: Equipment used directly in the manufacturing operation to make or
cause a physical or chemical change to the product qualifies for exemption.

RGA, Residual Gas Analyzers

This is a specialized type of mass spectrometer used in a semiconductor
cleanroom and other manufacturing operations to monitor processing environments
(detect leaks of gases) to ensure proper processing conditions are met.

Response: A semiconductor manufacturer may give an exemption certificate to
purchase cleanroom equipment tax free. A manufacturer using the residual gas
analyzer to perform quality control testing of the product during the
manufacturing process may give an exemption certificate.

Halogen Leak Detectors, Eco Tek, D-Tek

These detectors are used in the refrigeration and air conditioning (HVAC)
industries to detect leaks in refrigerant systems.

Response: A manufacturer of refrigeration and air conditioning using the
halogen leak detector to perform quality control testing of the product during
the manufacturing process may give an exemption certificate. A contractor that
installs or repairs HVAC equipment in real property is not a manufacturer and
may not claim a manufacturing exemption for a detector used in performing such
services.

Stationary and Portable Leak Detectors

Stationary and portable helium leak detectors are mass spectrometers tuned for
high sensitivity to helium that are used to verify leak integrity in wide
variety of enclosed systems (under vacuum or pressurized). Some examples
include automotive industry cooling systems, gasoline tanks and braking
systems, semiconductor fabrication vacuum chambers, space simulation apparatus,
and pressurized gas delivery or storage systems.

Response: A semiconductor manufacturer may give an exemption certificate to
purchase cleanroom equipment tax free. A manufacturer using the stationary and
portable helium leak detector to perform quality control testing of the product
during the manufacturing process may give an exemption certificate. A
repairman repairing a motor vehicle or a gas delivery or storage system is not
a manufacturer and may not claim a manufacturing exemption for a detector used
in performing such services.

HAPS

The HAPS field portable Gas Chromatograph / Mass Spectrometer (GC/MS) uses gas
chromatography and a quadrapole mass spectrometer for qualitative and
quantitative analysis of volatile organic compounds (VOCs). The instruments
are used in hazardous-waste site investigations, emergency response monitoring,
industrial smoke stack emissions, and monitoring other airborne pollutants and
hazards.

Response: A manufacturer has an exemption for tangible personal property used
or consumed during the actual manufacturing, processing, or fabrication of
tangible personal property for ultimate sale if the use or consumption of the
property is necessary and essential to a pollution control process or if the
use or consumption of the property is necessary and essential to comply with
federal, state, or local laws or rules that establish requirements related to
public health. If the HAPS is used by a manufacturer in the manner described
above, the manufacturer may give an exemption certificate.

An environmental investigator or a company performing environmental clean up
services is not a manufacturer and may not claim a manufacturing exemption for
HAPS used in performing such services. Of course, purchases by the federal
government (EPA) or by the State of Texas (Texas Natural Resources Commission)
are exempt purchases by governmental entities. A purchase voucher is
sufficient proof of exemption from an exempt federal, state, city, or county
government agency.

Inficon Gauges

The gauges are used to measure the level of vacuum obtained inside a vacuum
chamber.

Response: A semiconductor manufacturer may give an exemption certificate to
purchase cleanroom equipment tax free. A manufacturer using the Inficon gauge
to perform quality control testing of the product during the manufacturing
process may give an exemption certificate.

LES/OES

The LES/OES product line is used in semiconductor fabrication cleanrooms. The
LES product is a CCD camera that is focused on the semiconductor wafer during
processing to make crucial measurements (rates, thickness, etc.). The OES
product makes use of the optical information contained in a semiconductor
plasma etch process. The optical signals are transmitted to a
spectrophotometer using a fiber optic cable. This information is statistically
analyzed and used to determine the end point of the etch process.

Response: A semiconductor manufacturer may give an exemption certificate to
purchase cleanroom equipment tax free.

Composer

The composer uses an acoustical cell transducer to measure the speed of sound
in a binary gas mixture. The speed of sound is used to measure the gas
composition and thereby control the concentration of gas delivered to the
semiconductor manufacturing process. The composer is used in compound
semiconductor manufacturing processes known as metalorganic chemical vapor
deposition (MOCVD).

Response: A semiconductor manufacturer may give an exemption certificate to
purchase cleanroom equipment tax free.

This opinion is based on the facts you submitted. Other facts, though similar,
may yield different results.

You may call me toll free at 1-800-531-5441, ext. 5-0030. The direct line is
512/475-0030. You may also write to Tax Policy, Comptroller of Public
Accounts.

Sincerely,

David Somerville
Tax Policy Division