Japanese Industrial Standards

Table of Contents

Introduction

Japanese Industrial Standards or "JIS" are a body of standards covering a wide range of industrial goods, including hand tools.

This article will explore various aspects of JIS as it pertains to hand tools, with a particular emphasis on the development of JIS from the 1950s to 1990s.

Background History

In 1949 Japanese law created the Japanese Industrial Standards Committee to develop standards for industrial goods. The resulting standards (commonly known as JIS) became a major factor in the development of Japanese industry by emphasizing the importance of quality control and quality improvement.

Companies whose tools met the relevant standards became "JIS-Certified" and were allowed to mark their tools with a special JIS symbol.

Standards for Hand Tools

JIS testing has different standards for different types of tools, and a company that makes many kinds of tools would need to pass a number of tests in order to offer JIS certification for their entire line. The JIS standards evolved over time as new standards were enacted or modified, and some standards were discontinued in the process.

In general the standards for hand tools are expressed as a JIS class, consisting of a "B" prefix followed by a four-digit number of the form B46xx.

The table below shows the JIS classes relevant to the tools of interest at Alloy Artifacts, and the "Notes" column includes a link to the formal definition for the class. (Note though that the formal definition is for the current revision of the class, and some of the classes have gone through several revisions.)

As might be expected, testing standards have been revised over the years, with the result that sometimes earlier tests are not directly comparable with later tests.

For example, initially adjustable wrenches were split into two classes based on the jaw offset angle, with 15 degree offsets in B4604 and 23 degree offsets in B4605. The standard was changed in 1954 and class B4605 was folded into B4604.

As another example, socket tools were originally placed in classes B4636 to B4641 based on the functional type, but a 1998 revision placed all socket tools into revised classes B3636-1 or B4636-2 based on the drive size. A side effect of the 1998 revision was that some prior results apparently couldn't be classified into drive sizes and were instead lumped into an odd 00225 class.

We are currently looking for a source for earlier revisions of the standards, in particular to understand when various suffix designations became applicable.

JIS Suffixes

Sometimes a JIS symbol will be followed by a letter code, of which "H" appears to be most common in our examples, but "N", "P", or "S" may also appear.

The "N" and "H" codes apply to certain JIS standards (such as B4604 and B4630) that have been split into a "Normal" or ordinary class and a "Heavy-Duty" or strong class. Presumably this means that additional (or more difficult) tests had to be passed to be able to display the "H" suffix.

The split into JIS-N and JIS-H for classes B4604 and B4630 occurred around 1955, and in some cases the absence of a suffix may provide information on the manufacturing date. The establishment of the JIS-H class may have been motivated by the increased use of alloy steel during the early 1950s.

The "S" code applies only to standard B4630 (open-end wrenches) and designates a "spear type" style with slightly elongated jaws.

The "P" code applies only to adjustable wrenches (B4604) and indicates a partially forged product, meaning a wrench with a malleable iron body and a forged movable jaw.

After the initial recognition of "N" and "H" grades in the mid 1950s, some other classes (such as B4623) were later split into "N" and "H" grades as well.

From these brief descriptions it should be apparent that the suffixes represent a sub-class of the associated product class. Thus if we ask how the suffix qualifications should be reported, to us the most logical approach would have been to list the qualifying suffixes after the class. For example, if a company passed the tests for open-end wrenches in normal and strong grades, the certification could be reported as class "B4630 NH"

What was done instead was to add some phrases in Japanese to a "notes" field listing various attributes of the product. The table below shows the phrases typically used to denote each suffix.

(The opposite of partial forging was 全鍛造品 or "fully forged product".)

In order to determine whether any suffixes apply to a test, you have to scan the notes field for any of these particular phrases and then add the indicated suffix. And to make matters more difficult, the JIS monthly reports didn't provide a notes field until 1971, and some of the JIS summary reports omitted the "notes" field entirely! 😢 We'll have more to say about this in a later section on reporting.

One further complication is that in at least one case, a later revision of the standard removed the suffix grades. Class B4623 (side-cutting pliers) at one time recognized "Normal" and "Heavy" grades, but later had only a single standard. This means that in order to properly track the applicability of suffix designations, the revision history of the standard must be considered.

Administration

The Japan Industrial Standards Committee defines the test standards, but the administration of the JIS program involved other organizations as well. Inspecting factories and recording test results was only one aspect of the program, which also required publishing test results and making decisions about revocations or other exceptional events.

Initially the certification tests were administered by MITI, the government trade ministry. MITI handled test administration from its beginning in 1951 up through 1961.

In 1962 responsibility for certification passed to the Japanese Standards Association (日本規格協会 or "JSA"), but MITI apparently remained as the overall administrative authority.

Then in 2005 the JQA took over responsibility for certification, or in the lingo of modern international standards, assumed the role of "Certification Body". The latter change coincided with the change to a new JIS symbol, and tools marked with the new symbol will sometimes be marked "JQA" as well.

JIS certification involves more than just testing some tools, as it applies to the entire factory at a particular location. In some cases companies were required to be re-certified after simply moving their office functions!

JIS Numbers

If a company passes the required tests, it receives a certificate with an assigned number, and is then allowed to display that number as proof of certification.

When JIS testing began in the early 1950s the certificate numbers were assigned sequentially, making it possible to estimate a test date by the value of the number.

The numbering system changed in April of 1964 when responsibility for testing and issuing certificates was handed out to nine separate regional offices of MITI. The new numbers had six digits, with the first digit signifying the office as follows.

1. Hokkaido
2. Tohoku
3. Kanto (including Tokyo and Niigata)
4. Chubo
5. Kinki (including Osaka and Kyoto)
6. Chugoku
7. Shikoku
8. Kyushu
9. Okinawa

The second and third digits of the number specify the calendar year (in the Western calendar!) when the certificate number was first issued. The last three digits were then sequential, but only within the region.

The numbering changed again in 2005 when the JQA took over JIS testing in 2005, and numbers issued after this time will have a "JQ" prefix.

Reporting

An important aspect of the JIS program involved publishing reports of test results and public lists of certified factories. We are still investigating this part of the program, but our current understanding is that the JSA was responsible for publishing the "JIS認証月度レポート" or "JIS Certification Monthly Report", the primary vehicle for reporting certification changes. The Monthly Report provided timely information on new test results as well as revocations, factory changes, or other updates.

The Monthly Report was supplemented by summary reports published on an irregular basis every few years or so. These summaries were first called the "Factory Name List", then in 1962 became the "JIS表示許可工場名簿" or "List of Factories Approved for JIS Certification". (For brevity we will call this the "Certified List".) Our current understanding is that the JSA was also responsible for publishing the summary reports.

From the beginning the Monthly Report had some shortcomings in that it omitted significant information from its lists of certifications. Reports from the early 1950s showed only the company name and factory address, without the JIS number, the exact date, or the exact product class for tables covering multiple classes. (Each report covered a range of dates, so the test date was only known within the range.)

The reader can gain a better understanding of these reporting limitations by examining the 1952-01 Monthly Report for Classes B4604/B4605. This historically important report shows a list of five companies under the heading "Wrenches", and these turn out to be the earliest certifications for adjustable wrenches. But from this report alone we don't know the assigned JIS numbers, the actual date, or which class of tool.

These problems were gradually corrected over time — by 1958 the Monthly Report had added the JIS number and class, but it wasn't until 1971 that the exact date was provided for each certification.

The problem became more acute around 1954-1955 when class suffixes were added for certain classes. (See the section on JIS Suffixes for more information.) The suffixes depended on placing specific phrases in a "Notes" field for reporting, but initially there was no provision for publishing the notes! The 1958 Factory Name List was the first summary report to add a "Notes" field, and again it wasn't until 1971 that the Monthly Report included a column for the product notes.

For us it was rather shocking to discover such a long lapse before the product notes were properly reported. To highlight this problem, we made an excerpt from the earliest Monthly Report (available to us) with product notes, which the reader can view as the 1971-02 Monthly Report for Maruto Hasegawa.

The absence of a provision for publishing the notes may have resulted in the loss of important information from the early JIS era. Consider the case of a company that initially passed the tests for class B4630 and later wanted to upgrade their certification for "H" grade. Presumably this would require additional testing, since the standards for "H" grade are more stringent.

But if an additional test was performed, would the test have been published in the Monthly Report, knowing that there was no way to explain that the test covered class B4630 "H" grade? Or would the inspector simply have made a note to include the "H" suffix in the next summary report? Or perhaps the JIS inspectors just let the companies to do the testing themselves and took their word for it?

What we do know that is that in many cases the summary reports included product notes implying JIS suffixes for earlier certifications, without any obvious intervening test in the Monthly Reports to show exactly when the suffix was granted. Since companies typically start marking their tools soon after the tests are passed, it would be very helpful for estimating production dates if we knew exactly when a certain suffix was granted.

We are still investigating these problems and hope to find some way to restore some of the missing data.

The JIS summary report publications — the Factory Name List and Certified List — also had occasional problems, but these seem to be due to faulty execution rather than bad design. The 1962 and 1964 Certified Lists offered everything that could be expected, with the JIS number, the test date, and the products notes all available. Then inexplicably, the 1967 Certified List omitted the test date.

The test date was restored in the 1972 Certified List, but then the 1982 Certified List was published with an egregious error: the notes column was missing!

To understand how serious (yet puzzling) this problem was, the reader may want to take a look at the 1982 Certified List for Classes B4623-B4625. In the scan from the published report you can see the carefully prepared header with a key showing a numbered circle for each of the three classes, but the "Notes" column to display the numbered circles is missing, so that we don't even know the applicable products for the test! 😢

If it were possible to issue a "product recall" for a published JIS report, we would like to see the JSA republish the 1982 Certified List with corrections.

Compliance with Standard

The JIS standard appears to include mechanisms to ensure compliance, in the sense of ensuring that any tool with a JIS marking was made in a factory certified for production of that type of tool.

ID Marks

Companies that have a JIS certification are expected to mark their tools with the company's own brands and forge marks, and periodic publications provide a list of factories with JIS certifications.

Our original inference was that every company must have provided information on its brand markings and symbols at the time of certification. However, we were wrong — the JIS certification process does not capture the ID marks used by a company, and instead these marks are expected to be "well known" by the industry.

Outsourced Production. The situation becomes more complicated in the case of outsourced or contract production. Suppose that company A has JIS certification itself, but wishes to have company B make a certain tool, and that the tool will be marked with company A's brand.

In order for the tool to carry the JIS marking, company B must be certified to produce that type of tool, and in addition company B must add its own identifying mark near the JIS symbol, so that the JIS certification can be traced to company B.

The net result of these compliance measures is that (in our understanding) there should be no anonymous tools with JIS markings — every tool with a JIS symbol must be traceable to a particular factory. A corollary of this is that companies with multiple factories would need to have a distinct marking symbol for each factory.

We hope to discover the identifying marks used by the companies listed here, and will document the marks in the "Tool Identification" section for each company.

Relinquishment of Certification

Companies may be required to relinquish their JIS certification in the event of a bankruptcy or other business interruptions. The logic here seems to be that if the company's management or procedures have been disrupted, they may no longer be able to ensure the quality control necessary for production.

In such cases, a company might wish to temporarily outsource production while it tries to recover from the problem, and the notes pertaining to JIS markings for outsourced production in the previous section would apply.

Consolidation of JIS Numbers

In this section we will describe a somewhat mysterious and entirely undocumented aspect of JIS administration, which we refer to as JIS consolidation.

As new classes of tools were added to the JIS testing standards, some companies found themseleves holding multiple JIS numbers for closely related classes of tools. For example, a maker of pliers that originally received certification for classes B4623-B4625 might have later received different numbers for classes B4631 and B4635.

Since having multiple JIS numbers increased the reporting and administrative burden, in the early 1990s the JIS administration decided to consolidate multiple JIS numbers within related classes into just a single number. As far as we know, this consolidation program was not documented in any published reports, and we discovered it only after noticing that some companies with multiple JIS numbers in earlier summaries had only a single number in the 1999 summary. In addition, we noted that some certifications that had been canceled were later reappearing under a different JIS number.

The basic rule used for the consolidations was that a manufacturer's oldest active JIS number (within the group of classes) would be chosen as the survivor, and the other JIS numbers would then be canceled, with the classes reassigned to the surviving number. The date used for the combined certifications would be the active date for the surviving JIS number.

The classes subject to consolidation were pliers (classes B4623-B4625, B4631, and B4635), wrenches (classes B4630, B4632, and B4651), and sockets (classes B4636-B4641). In the case of sockets, the consolidation was a first step to reorganizing the classes based on drive size instead of functional type, a process not completed until 1998.

At this point it might be helpful to consider an actual example of the consolidation process. Three Peaks Giken is a maker of pliers operating in Niigata prefecture, and by 1980 the company had received JIS certifications for four classes, B4623, B4625, B4631, and B4635. These were spread over three JIS numbers, 367229 (B4623/B4625), 371247 (B4631), and 371248 (B4635). All three JIS numbers had the same December 5, 1975 date due to a factory move, but historically 367229 was the company's earliest certification.

If we now move forward to 1991, the JIS Monthly Report for November of 1991 reported that on March 27, 1991 JIS numbers 371247 and 371248 were canceled. (See the Aggregated Monthly Reports for 1991-11.) And then if we look at the 1999 JIS Summary, we see that Three Peaks Giken is listed with JIS 367229 for all four classes.

We sent email to Three Peaks asking for information on the cancellations and consolidation, and the company responded that they had received a letter in February of 1991 from the Kanto Bureau of MITI explaining the impending cancellations. The letter explained that the goal of the program was to group the separate classes into a single category of pliers and nippers, and that companies with multiple certifications would have the certifications reassigned to the earliest number.

The letter further clarified that even though certifications were being canceled, the company was not being asked to suspend production of the affected items. We take this last point to mean that the reassignment of the certifications was being treated as simultaneous with the cancellations, even though there was no public report to show that the reassignments had occurred.

The goals of the consolidation program seem reasonable, but in our opinion the way it was implemented was very confusing. The main problems were that there was no public explanation of what was being done, no explanation that the cancellations were purely administrative in nature, and no timely report showing the reassigned JIS numbers for the canceled certifications. The cancellations occurred in the early 1990s, and it wasn't until 1999 that a summary report showed the reassignments!

The above summary of the JIS consolidation program may be the first time the program has been described in public, and we hope this will be helpful for some of our readers.

Tool Identification

A tool that has passed the relevant JIS standard for its class is allowed to include the JIS symbol marking, as noted below. In addition, the tool is expected to carry a marking for the manufacturer's name or well-known brand, so that anyone wishing to verify the JIS qualification can check using published records.

A tool made as contract production is allowed to carry the JIS symbol marking provided that it also carries the JIS number or special ID mark of the actual manufacturer.

JIS Symbol

Fig. 1 shows the JIS Unicode symbol U+3004 resembling "JIS" in a circle, read from top to bottom and right to left.

We will refer to this symbol as the JIS-Circle logo in the text. This is actually the older version of the JIS symbol and was in use from the 1950s until 2008.

The newer JIS symbol was phased in beginning in 2005 and consists of the text "JIS" with the hook of the "J" extended to a circle. It is not yet available as a Unicode entity.

JIS-Circle Logo

Fig. 2 shows the JIS-Circle logo as found forged into a tool.

The JIS-Circle mark is stamped on or forged into a tool that has passed the JIS quality standards.

References and Resources

The Japanese Industrial Standards Committee (JISC) offers a Database Search [External Link] website that allows searching for various JIS-related topics, including definitions of the JIS standards as well as currently active certifications.

JIS Resources

The following archived links have JIS information (in Japanese).

• JIS Tests [External Link]
• JIS Classes [External Link]

CWC Website

Historical information on Japanese tool companies can be found (in Japanese) at the コンビネーションレンチ･コレクション Combination Wrench Collection [External Link] web site. We will refer to this reference as "CWC" in the text.

JIS Database

The CWC Japanese website is currently doing historical research on JIS certifications, including reconstruction of lost records for the early (1951-1961) era. We think this information is important for understanding the Japanese tool industry, and as a result have developed a database to organize and present the JIS certification data.

To keep the project manageable, the scope of the database has been limited to the classes of tools listed in the section on Standards for Hand Tools above.

Currently the project has reached a mature phase and most of the important JIS certifications have been entered into the database. A few records are still missing, and we are actively searching for sources to fill the remaining gaps.

To our knowledge, this database is the most complete source of JIS certification data for the hand tool industry, and it is the only searchable database with information going back to the 1950s. We hope that our readers will find it useful.

The section below will provide examples of the reports that can be generated from the database, as a way of showing the type of information available.

We also provide a free-form search facility so that our readers can create their own reports.
Jump to Free-Form Search

Examples of Database Reports

This section will provide some examples of database reports as a way of introducing the content and structure of the database.

Company History with Factory Locations

Our first example provides a table of all of the companies and factories in the JIS database, with the intent of presenting a concise history for each company.

Companies and factories are two of the basic building blocks of the database, with companies representing business entities in the hand tools industry, and factories representing a physical location where hand tools are manufactured. Each company and factory has a beginning and ending year to define its period of activity.

In the real world companies may occasionally undergo name changes or reorganizations while remaining in the same line of business. The database supports this by recognizing that a series of company names may be associated with a single final entity, which we refer to as the "successor company".

It's common for companies to build new factories as the business grows, but in most cases a company will have only one factory in operation at any point in time. In some cases though a company may operate multiple factories simultaneously.

Note that this report does not provide any JIS certification data, but the fact that a company is listed here means that a predecessor or successor received JIS certification at some point.

At this point the reader may wish to refer to the table below, which provides a sample of the report for a single company, AIGO Kōgyō, together with its business predecessors.

The first thing to note is that the database includes a mix of Japanese and English, with the company name available in both languages, and with the full Japanese address for factory locations. This makes the information available to both languages without the need for additional translation.

The second column shows three businesses in succession, with the last being AIGO Kōgyō as the successor company. Note that the company and factory names are followed by the years of operation in parentheses.

The fourth column shows the factory name and its years of operations. Note that AIGO Kōgyō has two factories listed, Shinbo and Tsukanome, and the years of operation show that these factories operated sequentially, with Shinbo closing in the same year that Tsukanome opened. If AIGO had operated multiple factories at the same time, the years of operation would show some overlap.

The following link provides the full report:
Company Histories with Factory Locations

JIS Certifications by Successor Company

Our next example provides a table of all of the JIS certification events in the database, grouped by successor company and sorted chronologically within the company.

JIS events are the third major building block of the database, with each event representing a test result for a specific company and factory. The data associated with the event includes the class of tool, the certification and reporting dates, the type of the event, and the JIS certificate number.

The table below shows a sample of the report for AIGO Kōgyō, the same company presented in the previous section. The report is grouped by the successor company, which is listed in the highlighted row at the top, and each of the following lines then represents a certification event for a company and factory.

In this report we see that the earliest certification was in 1966 for JIS 366008 at the Shinbo factory, and that the certifications are later repeated at the Tsukanome factory. When a company moves to a new factory, normally the existing certifications are canceled for the old factory and then re-certified at the new factory. In the case of AIGO, we don't have the records for the cancellations and re-certifications. (This is an example of missing data that we hope to provide at some point.)

The last column ("Notes") provides a link to document the source of the data.

The following link provides the full report:
JIS Certification Events by Successor Company

JIS Query for Class B4604

This next report shows an example of a simple free-form query, in this case for just a single JIS class 'B4604' for adjustable wrenches.

Additional information on this kind of query can be found in the section on "Free-Form Search" below.

Analysing query 'b4604' ...
Token 'b4604' classified as JIS class ..

JIS Certification Events Matching Query 'b4604'

The following link provides the full report:
JIS Certification Events for Class B4604

Database Maintenance Reports

The links below provide reports intended primarily for maintaining and checking the database.

• List of Factories by Successor Company
• JIS Certification Events by Date

Free-Form Search

To provide convenient access, we have created a free-form query facility that allows you to search the JIS database for events matching any combination of company name, ID mark, JIS number, JIS class, or JIS super-class. You can enter a search in the box below:

JIS Query:

The results of the query will show the JIS events (if any) that match all of the input keywords. For example, entering "3064" would show the JIS events having 3064 as the JIS number, and entering "B4604" would show all JIS events for class B4604 (adjustable wrenches).

A few rules for the search to keep in mind:

• A search consists of one or more keywords ("tokens") separated by spaces.
• The search is case-insensitive.
• The search generates a report of the JIS events matching all of the keywords.
• JIS numbers should be entered as a string of digits, with a "JQ" prefix for new numbers.
• JIS classes for tools are in the form B46xx, such as B4604 or B4630.
• JIS super-classes for tools are in the form B0xx, such as B010 or B027. The product categories "Wrenches", "Pliers", and "Sockets" are also treated as super-classes.
• Company names can be entered in English or Japanese, and only part of the name is required.
• A name spanning multiple words can be joined by an underscore (_) to make a single token.

Certain ID marks with special graphics have a two-character abbreviation in the database, in particular I-Circle (I○), I-Diamond (I◇), and 3-Blocks (▮▮).

Please try out the new JIS search facility, and let us know if you find any problems!