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Introduction to JPEx Certification

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updated: May 14, 2025

Table of Contents

Introduction and Basics

Why is Japanese Certification (JPEx) Required Even for IECEx/ATEX Certified Products?

Why is JPEx Examination Necessary Even for IECEx/ATEX Certified Products?

Japan's Unique Legal System and the Public Responsibility of Certification Bodies

Utilization of Test Data and the Certification Body's Responsibility for Final Conformity Assessment

Mandatory Requirements Under Current Legislation

Conclusion

Standards(JPEx current editions)

Product range on a single certificate

Example cases in which separate certificates are issued;

Table 1

Element (1): Type of equipment

Element (2)-1: Type of protection According to JNIOSH-TR-46(2015)

Element (2)-2 : Type of protection According to JNIOSH-TR-46(2018)

Element (2)-3 : Type of protection According to JNIOSH-TR-46(2020)

Element (3): Rated voltage

Element (4): Gas group

Element (5): Dust group

Element (6): Temperature class

Element (7): EPL for gas

Element (8): EPL for dust

Element (9): Type of entry method from main enclosure into terminal box

Simple apparatus

Introduction and Basics

According to Japanese laws and regulations, any electrical equipment intended for use or installation in hazardous areas in Japan must have a JPEx certificate issued by a JPEx certification body. This body is an Ex certification entity registered with the Ministry of Health, Labour, and Welfare (MHLW).

While ATEX/IECEx certificates are often issued based on standards equivalent to JPEx standards, these certificates do not hold legal status in Japan. However, this does not render ATEX/IECEx certificates entirely useless. The test data generated during those certification processes can be utilized to support the JPEx certification application.

NCS is happy to provide certification services and assistance to manufacturers entering the Japanese market. Feel free to contact us at support@ncs-ex.com in Japanese or English.

Here is the basic information about JPEx certification:

A JPEx certificate is valid for 3 years.
There are no audit requirements.
A certificate can be renewed for an extension of the validity period:
- Renewal can be accepted as long as there is no significant design change.
- The application package for certificate renewal must include the original certificate (paper form).
- After renewal, the certificate is valid for another 3 years.
Product design changes that require testing would necessitate a new certificate.
Certificate holder is required to affix a specific certification label to the product. See our website: Japanese Certification Label

Why is Japanese Certification (JPEx) Required Even for IECEx/ATEX Certified Products?

Thank you for visiting our website.
Our company, NCS, operates as a Registered Type Examination Body for explosion-proof certification, registered by the Ministry of Health, Labour and Welfare of Japan, and conducts Type Examination services (commonly known as JPEx).

One of the most frequent questions we receive from importers and manufacturers outside Japan is indeed the one posed by this title. "Why is a new examination required in Japan even though our products already have IECEx or ATEX certification?" — We have prepared this guide to answer this question, help deepen your understanding of Japan's explosion-proof certification system, and facilitate smoother certification procedures in the future.

Why is JPEx Examination Necessary Even for IECEx/ATEX Certified Products?

While IECEx and ATEX certifications are widely recognized internationally, to use explosion-proof electrical machinery and equipment in Japan, a separate Type Examination (JPEx) based on Japanese laws is required. The main reasons are as follows:

1. Japan's Unique Legal System and the Public Responsibility of Certification Bodies

Japan has its own explosion-proof certification system to ensure industrial safety domestically, with procedures and technical standards stipulated by law.

Registered Type Examination Bodies such as ours bear the public responsibility of certifying the safety of products distributed within Japan, and the Type Examination Certificates we issue carry legal force.

This concept is similar to certification systems in other countries. For example, even if a product passes Japan's JPEx, it cannot automatically be distributed as an ATEX-certified product in the EU, nor can it bypass the respective certification procedures required in North America, China, South Korea, Taiwan, and other regions.

2. Utilization of Test Data and the Certification Body's Responsibility for Final Conformity Assessment

Many of the technical standards for Japan's explosion-proof certification (JPEx) are based on international IEC standards.

Therefore, test data (test reports) created during IECEx certification are respected and actively utilized in our JPEx examination process. In particular, the IECEx ExTR (Ex Test Report) contains not only test results but also detailed records of how the product was evaluated, which is highly effective in facilitating a smooth examination process at our institution (NCS). If we can confirm that these tests were conducted appropriately, re-testing by us is generally not required.

However, the responsibility for the final judgment on whether the submitted documents and the product itself conform to Japanese technical standards, and for deciding whether to grant certification, lies with us as the issuer of the Type Examination Certificate. Specifically, we conduct a comprehensive assessment by comparing design drawings against standard requirements, verifying the actual product against drawings, and through other evaluation procedures.

3. Mandatory Requirements Under Current Legislation

Under current Japanese law, even products with IECEx certification are not permitted for use in Japan solely on that basis. To use explosion-proof electrical machinery and equipment in Japan, it is mandatory to undergo examination and certification (JPEx) by a Japanese Registered Type Examination Body.

Conclusion

Japan's explosion-proof certification system plays an extremely important role in improving occupational safety and health standards and preventing industrial accidents within the country. Your understanding and cooperation are essential for ensuring a smooth certification process and facilitating the seamless introduction of your products into the Japanese market.

We hope this guide will assist you in understanding Japan's explosion-proof certification system.
If you have any questions, please do not hesitate to contact us.

We appreciate your continued understanding and cooperation.

Standards(JPEx current editions)

valid from Aug 18, 2021 to present

List of valid JPEx Standards

Product range on a single certificate

There is a rather unique rule that can be very complex in Japanese regulations regarding what could be covered on a single JPEx certificate, which is quite different from the approach adopted in IECEx or other certification schemes. Depending on the contents of your IECEx certification, you could end up with multiple JPEx certificates for a product range that may be covered on a single IECEx CoC.

Suppose you have a representative model for which you prepare a set of JPEx application documents. You might have other model included on the same IECEx CoC, which is a variational model with respect to the representative model. For example, models with different protection concepts(e.g. Ex d and Ex t), enclosure material, ambient temperature designation, or gas group and so on with respect to the representative model. In order for the variational models to be covered on a single JPEx certificate along with the representative model, certain conditions must be met as described below. If a variational model does not meet these conditions, a separate certificate needs to be issued.

The conditions are as follows:
A variational model may not be regarded as belonging to the same model type as the representative model IF any of the element described in Table 1 (in this document) is different from that of the representative model. On top of the constraints from Table 1, there are another set of elements described below to be taken into account.

Shape of major part of the equipment
Specifications of the equipment related to safety performance
Material of part(s) on which the type of protection depends
Conditions affecting cooling property

As a part of your application documents, you need to submit a list of variational models you wish to include in a JPEx application. Also, in order to support that those variational models may be regarded as belonging to the same model type as the representative model, documented exlanation describing why those models may be regarded as such need to be submitted.

Example cases in which separate certificates are issued;

Equipment with multiple types of protction in the sense of clause 29.7(Multiple types of protection) of IEC 60079-0:2017 will end up with two separate JPEx certificates.

For instance, an equipment having the Ex code,

Ex db IIC T4 Gb Ta=-20℃ to +60℃ Ex tb III C T135°C Db IP6X ,

will end up with, at least, two separate certificates ;

Certificate 1: Ex db IIC T4 Gb Ta=-20℃ to +60℃
Certificate 2: Ex tb III C T135°C Db IP6X .

Another example is illustrated in the table below;

Model Type 1	Model Type 2	Can they covered on a single JPEx certificate?
Ex db IIB T5 Gb thermometer	Ex db IIB T6 Gb thermometer	No
Ex db IIB T5 Gb thermometer	Ex db IIC T5 Gb thermometer	No
Ex db IIB T5 Gb thermometer	Ex eb IIB T5 Gb thermometer	No
Ex ib IIB T5 Gb thermometer	Ex ib IIIB T100℃ Db thermometer	No
Ex db IIB T5 Gb thermometer	Ex db IIB T5 Gb pressure gauge	No
Ex db IIB T5 Gb pressure gauge；enclosure material=stainless	Ex db IIB T5 Gb pressure gauge; enclosure material=aluminium	No

More examples will be added to the list for more useful guide.

The above does not apply to equipment having combined types (or levels) of protection in the sense of clause 29.6 of IEC 60079-0:2017. It will end up with a single JPEx certificate.

For an equipment having the Ex code,

Ex db eb [ia IIA Ga] IIB+H2 T5 Gb, Ta= $-$ 40℃ to $+$ 60℃

a single certificate is issued.