PSC H166

Overview

The Product Service Code (PSC) system standardizes how the U.S. federal government classifies products and services in procurement records; PSCs are used in FPDS/SAM reporting and are maintained and published through the PSC Manual and related GSA materials to support tracking, analysis, and reporting of government spending. The PSC listed as H166 is titled “Quality Control‑ Instruments and Laboratory Equipment” and is placed in Category H (Quality Control, Testing, and Inspection) of the PSC Manual. The manual gives the official code title and placement but does not publish a granular, item‑level includes/excludes list for H166; contracting officers and data reporters must interpret the code in the context of the transaction and agency policy. ¹

• See also on G2X:
  • G2X — PSC H166 overview: https://app.g2xchange.com/psc/H166
  • G2X — PSC H266 (Equipment & Materials Testing — Instruments & Laboratory Equipment): https://app.g2xchange.com/psc/H266
  • G2X — PSC H366 (Inspection — Instruments & Laboratory Equipment): https://app.g2xchange.com/psc/H366

What this PSC covers

• Quality‑control services directed at instruments and laboratory equipment, including programmatic oversight, inspection planning, and documentation of acceptance criteria. ¹
• Instrument calibration and measurement verification activities when procured as a discrete quality‑control service rather than as operational testing — Not specified by official sources. ¹
• Maintenance, repair, and testing support to restore or verify instrument performance when the primary procurement is a quality‑control service rather than equipment acquisition — Not specified by official sources. ¹
• Procurement or supply of laboratory testing instruments only when the acquisition is primarily framed as a quality‑control solution rather than simple product purchase — Not specified by official sources. ¹
• On‑site acceptance testing and performance verification of instruments as part of a quality assurance or inspection scope. ¹

Related NAICS and PSC codes

Type | Code | Descriptor

• | - | - PSC | H266 | Equipment and Materials Testing — Instruments and Laboratory Equipment PSC | H366 | Inspection — Instruments and Laboratory Equipment PSC | H966 | Other Quality Control, Testing, and Inspection — Instruments and Laboratory Equipment

Source: PSC Manual. ¹

Acquisition context

FAR policy emphasizes tailoring contract quality requirements to the technical description, complexity, and criticality of the item or service; contracting officers apply quality assurance clauses, source inspection, and contractor inspection responsibilities consistent with FAR Part 46 when quality control services are required. Agencies determine whether to include contractor QC requirements, government QA, or hybrid approaches based on risk and mission needs. ²

FPDS coding and reporting

In FPDS, PSCs record the “what” of a purchase in data element 8A; selecting the correct PSC should reflect the predominant supply or service on the contract action. The PSC Manual together with FPDS guidance govern selection and reporting practices, including when to report a service PSC (such as H166) versus a product PSC. Contracting officers and data entry personnel should follow FPDS help resources and agency rules to ensure consistent coding. ³

Frequently asked questions

• What is the short definition of PSC H166?
  PSC H166 is the PSC Manual entry titled “Quality Control‑ Instruments and Laboratory Equipment.” The manual lists the code within Category H but does not provide a granular includes/excludes list for H166; interpretation is by contracting context. ¹

• How does H166 differ from H266, H366, and H966?
  H266 is oriented to equipment and materials testing for instruments and lab equipment, H366 covers inspection services, and H966 captures other QC/testing/inspection functions not captured elsewhere; H166 is the general quality‑control service designation for this product group. See the related PSC entries for function distinctions. ¹

• When should a contracting officer use H166 versus a product PSC?
  Use H166 when the contract’s predominant requirement is a quality‑control service for instruments or laboratory equipment. If the primary acquisition is the equipment itself or a distinct testing contract, select the corresponding product or testing PSC per FPDS guidance. ³

• Which NAICS codes apply to H166 actions?
  The PSC Manual does not publish a single mandatory NAICS mapping for H166; NAICS selection depends on the primary activity (manufacture, repair, inspection, or service). Agencies should follow FPDS NAICS guidance and internal policy to choose the most appropriate NAICS. ¹

Useful resources

• G2X — PSC H166 page: https://app.g2xchange.com/psc/H166
• Product and Service Code Manual (PSC Manual, April 2025 edition). ¹
• FAR Part 46 — Quality Assurance. ²
• FPDS Help / ezSearch guidance (FPDS). ³

References

1. Product and Service Code Manual, April 2025 (Federal Procurement Data System / GSA). https://www.acquisition.gov/sites/default/files/manual/PSC%20Manual%20April%202025.pdf.
2. FAR Part 46 — Quality Assurance. https://www.acquisition.gov/far/part-46.
3. FPDS Help / ezSearch. https://www.fpds.gov/help/index.jsp.