Diamond PSE (特定電気用品, Specified Electrical Appliances) requires mandatory third-party certification by a METI-registered conformity assessment body, including a factory inspection, with certificates valid for 3, 5, or 7 years. Circle PSE (non-specified) allows self-declaration backed by accredited lab testing, no factory inspection, and no fixed expiration. Which one applies depends entirely on where your specific product sits on METI's designated list, not on the product category in general.
What Is the Difference Between Diamond PSE and Circle PSE?
Diamond PSE and Circle PSE are two separate compliance paths under the Electrical Appliance and Material Safety Act (電気用品安全法, DENAN Act), and a product falls into exactly one of them based on its listing, not on how "risky" it appears. Diamond PSE covers the 116-item Specified list and demands a registered conformity assessment body (RCAB) to run testing plus a factory inspection before issuing a certificate good for a fixed term. Circle PSE covers the larger 341-item Non-Specified list and lets the manufacturer or its Notifying Supplier (届出事業者) self-declare conformity through accredited lab testing, with no third-party certificate and no expiration tied to a calendar.
The practical gap is procedural weight, not safety tier. A Diamond PSE file means ongoing renewal cycles and annual surveillance; a Circle PSE file means the design and the applicable standard stay frozen and the self-declaration stands indefinitely. Neither path is optional once a product is on either list, and neither path can be inferred from what competitors are doing with a similar-looking product. Our companion piece on PSE certification for foreign manufacturers covers the Notifying Supplier registration that sits alongside both paths.
How Do You Know Which METI List Your Product Falls Under?
You confirm it by checking the specific product, by its defined technical parameters, against the current METI designated lists, never by category assumption. METI maintains a Specified list of 116 items requiring Diamond PSE and a Non-Specified list of 341 items requiring Circle PSE; a product's placement depends on the exact wording of the ministerial ordinance defining that item, including rated voltage, rated output, and structure.
This is where blanket classification breaks down in practice. We have seen an internal reference table list an entire product line as Diamond PSE by category assumption, then walk back the determination on a per-product basis once each item was checked against the current designated list. The corrected result, after verification, was a small fraction of the original Diamond count, with most items landing as Circle PSE instead. The lesson holds regardless of who built the table: no internal reference document, however recently updated, substitutes for a per-product Applicability Assessment run against the live METI list at the time of quoting or import.
What Does Diamond PSE Certification Actually Require?
Diamond PSE certification requires third-party testing and a factory inspection by a METI-registered RCAB, ending in a certificate valid for a fixed term of 3, 5, or 7 years. The RCAB reviews the product against the applicable technical standard, which for plug-based products includes JIS C 8303 governing plug conformity for the Japanese market, and conducts a factory audit before certification is issued. Renewal at the end of the validity term is a formal re-application, not a rubber stamp, and annual surveillance audits run in the interim.
An existing IECEE CB Test Report can shorten the technical testing phase, but it does not remove the factory inspection or the RCAB's certification role; delta testing against Japan-specific requirements is still required on top of the CB basis. Power adapters and AC-input USB wall chargers are a common example of Diamond PSE exposure, specified under the 直流電源装置 (DC power supply device) category on the current 116-item list, alongside larger appliances such as electric water heaters, air conditioners, and certain classes of large refrigerator. None of that is a substitute for checking your own model against the ordinance text; the category label tells you where to look, not the answer.
What Does Circle PSE Self-Declaration Actually Require?
Circle PSE requires the manufacturer or Notifying Supplier to self-declare conformity, backed by accredited lab testing, with no third-party certificate and no factory inspection. The self-declaration (自主検査) rests on test results from an accredited laboratory against the applicable JIS or equivalent standard, and the record stays valid indefinitely as long as neither the design nor the governing standard changes.
Where the factory already holds a valid IECEE CB Test Report under the relevant IEC standard, the shortcut path uses that report as the base and adds delta testing for Japan-specific requirements only, which is usually faster and cheaper than starting a full JIS test program from zero. Microwave ovens, hair dryers, electric kettles, LED lighting, electric fans, and lithium-ion batteries are common Circle PSE examples; lithium-ion cells carry the added layer of dangerous goods classification under UN3480/3481 for transport, which is a separate regime from PSE and needs its own check. Our product compliance hub walks through how PSE interacts with PSC and food safety obligations for mixed product lines.
How Long Does PSE Certification Take Before You Can Ship?
As an operating estimate rather than a statutory deadline, Circle PSE certification through Aplash typically runs 6 to 8 weeks end to end, and Diamond PSE typically runs 8 to 12 weeks, including a 2 to 3 week METI Notifying Supplier filing that overlaps the tail of certification. Neither figure is a government-set processing period; both are Aplash's own delivery ranges based on how the certification and filing workstreams run in parallel, and both should be quoted as ranges, never as guaranteed dates.
The Diamond timeline runs longer because the RCAB testing and factory inspection sequence has more fixed steps than Circle's lab-testing plus self-declaration path, and because renewal cycles later add recurring time that Circle PSE does not carry. For import structures where a foreign manufacturer has no Japan entity, the PSE timeline sits alongside a separate importer-of-record decision; our Japan IOR guide for China-made electronics breaks down how that filing sequence interacts with PSE and Notifying Supplier status. Aplash coordinates the classification, the RCAB or lab liaison, and the Notifying Supplier filing as one sequenced workstream rather than three separate vendors.
Key points:
(a) Classification is per product against the current METI designated list (116 Specified items vs 341 Non-Specified items), never a blanket call based on product category.
(b) Diamond PSE means mandatory RCAB certification, factory inspection, and a 3, 5, or 7-year certificate with formal renewal; Circle PSE means self-declaration backed by accredited lab testing (or CB report plus delta testing), no factory inspection, and no fixed expiration.
(c) Timelines of 8 to 12 weeks (Diamond) and 6 to 8 weeks (Circle) are Aplash's own operating estimates, not statutory processing periods, and should be treated as ranges until the applicability assessment is complete.
Frequently Asked Questions
How do I find out if my product is Diamond PSE or Circle PSE before I commit to a supplier order?
Run a per-product Applicability Assessment against the current METI designated lists before placing volume orders; category assumption is the single most common source of misclassification. A product's parameters, not its general type, determine which of the 116 Specified or 341 Non-Specified items it falls under, and small spec differences (rated voltage, output type, structure) can move a model between categories.
Can I use my existing CE or CB test report to skip Japan-specific testing entirely?
No. An IECEE CB Test Report can serve as the base for both Diamond and Circle paths and typically shortens the process, but Japan-specific delta testing is still required against the applicable JIS standard, and Diamond PSE still requires the RCAB's factory inspection regardless of what the CB report covers.
Does Circle PSE mean the product never needs re-testing?
Circle PSE has no fixed expiration, but that status is tied to the design and the applicable standard staying unchanged. Any change to the product's construction or a revision to the governing JIS standard requires the self-declaration basis to be re-verified, and ongoing Notifying Supplier record-keeping obligations continue regardless of certification type.
Conclusion
Diamond PSE and Circle PSE are determined by where a specific product model sits on METI's designated lists, not by category instinct or a competitor's prior filing. Treat every product, including ones that look identical to something already cleared, as its own classification question until verified against the current list. Timeline and cost estimates that look precise before that verification step is complete are not reliable.
This article is informational only and does not constitute legal, tax, or regulatory advice. Consult a qualified advisor before acting on the content. Last updated: August 2026.