EMI Requirements in Japan
ITS Intertek Testing Services (Boxborough, MA)
The regulation of interference generated by computing
devices is well established in Japan, but its implementation
differs somewhat from that in other countries. Emissions
control is performed on a voluntary basis, under
the supervision of the Voluntary Control Council
for Interference by Information Technology Equipment
(VCCI). The VCCI was formed in December 1985 by
four Japanese industry associations in response
to a government request that electronics manufacturers
participate in the control of electromagnetic interference
(EMI). The Japanese Telecommunications Technology
Council presented the Ministry of Post and Telecommunications
with standards based on the internationally recognized
CISPR 22 recommendations, and industry responded
by organizing the VCCI as the mechanism to implement
a voluntary EMI-control program.
The VCCI compliance program is voluntary
in the sense that participation is not legally mandated;
however, it is widely supported by major Japanese
companies, and the meeting of its criteria, as evidenced
by the application of the VCCI compliance label,
is increasingly perceived as an indication of product
quality. Thus, though compliance is in theory voluntary,
marketing pressures encourage it in practice.
Compliance with the VCCI program has several
Equipment must meet the
VCCI technical requirements, with testing being
performed at a facility registered with the
VCCI. Such facilities are located all over the
world; there are several in the United States.
After being informed of the equipment's compliance
via a technical report, the VCCI will issue
a certificate of compliance.
Compliant equipment must
carry the proper VCCI labels. Prescribed user
information must also be included with the product.
Only members of the VCCI
are eligible to participate. Membership is open
to all interested parties, not only Japanese
manufacturers; members pay an initiation fee
and an annual membership fee (the precise amount
of which depends on the number of product registrations
a member submits) and agree to be bound by VCCI
regulations. Today there are about 600 VCCI
members, one-third of them outside Japan. Two-thirds
of these overseas members are located in the
The VCCI conducts a sampling
program, the expense of which is borne by the
equipment manufacturer. This program is analogous
to the postgrant sampling policies of the FCC's
Sampling and Measurement Branch. Equipment sampled
is subjected to testing at a laboratory of the
VCCI's choosing, with samples being deemed to
"conform" when conducted emissions are 2 dB
or more below the applicable limits and radiated
measurements are 3 dB or more below the limits.
Samples that fall into the "warning level" category
are judged to conform but will evoke requests
from the VCCI for improved QA documentation.
These conformance categories are closely related
to the measurement uncertainty associated with conducted
and radiated emissions measurements. In the event
that the sampled equipment does not conform, a complex
appeal-and-evaluation policy is applied to determine
what further actions will be taken. Such actions
may include mandatory equipment modifications or
revocation of the conformity certificate. Here again,
all members must abide by final VCCI decisions.
The current VCCI regulations for members
and test laboratories are:
V-1/93.11Agreement of Voluntary Control
Council for Interference by Information Technology
V-2/97.04Regulations for Voluntary Control
V-3/97.04Normative Annex 1: Technical Requirements.
V-4/97.04Normative Annex 1-1: Supplement
for Test Conditions for Requirement under Test.
V-10/94.06Normative Annex 1-3: Guidelines
for the Calibration and Inspection of Measurement
V-5/97.04Normative Annex 2: Regulations
for Registration of Measurement Facilities.
V-6/95.11Normative Annex 2-1: Guidelines
for Management of Measurement Facilities.
V-7/97.04Normative Annex 3: Regulations
for Market Sampling Tests.
The radiated and line-conducted emissions
limits established by the VCCI are identical to
those of CISPR 22 (1993), so that
VCCI Class A = CISPR 22 Class A, and
VCCI Class B = CISPR 22 Class B.
When the limits were first formalized at the end
of 1986, the VCCI offered a gradual phase-in. Equipment
was accepted for registration in 1987 so long as
it was within 10 dB of the respective CISPR Class
A or Class B limits; the product label applied indicated
the margin by which it exceeded CISPR. In 1988 the
acceptable margin was reduced to 4 dB, and since
1990, no products have been accepted by the VCCI
unless their emissions have met the correct CISPR
Labels and Instruction-Manual Information
Products accepted by the VCCI have earned
the right to display a label attesting to their
EMI control. For devices meeting Class A limits,
the label consists of a statement, in Japanese,
confirming that the product has met the requirements
of the VCCI for RF emissions. Class B products display
a simpler label: the VCCI mark.
Instruction manuals for VCCI Class A or Class
B products should also carry compliance information
in Japanese, in accordance with a standard format.
This merely provides more detail about the nature
of the VCCI approval and its significance to the
Since 1995, VCCI test laboratories have been
required to submit detailed site information for
approval. Organizational and operating information
showing basic quality system elements is also required.
Site approval is renewable every three years. The
site-attenuation methods are somewhat different
from those specified in either ANSI C63.4-1991 or
CISPR 22. For example:
Dipole attenuation factors
differ from CISPR 22 and ANSI C63.4
attenuation is permitted > 10 m, but dipoles
or shortened dipoles must be used at 3 m.
Volumetric site attenuation
is not required for sheltered sites, but is
mandatory for 3-m semianechoic chambers as of
April 1, 1999.
VCCI technical committees are active in collecting
and disseminating published EMC information to the
group's membership, and in visiting member test
laboratories and standards organizations around
the worldin Europe, Asia, and North and South
The VCCI has gathered extensive data on product
compliance and testing reproducibility in Japan,
by emissions class 1 or 2 and product category.
Based on that information, the VCCI has published
detailed testing guidelines for both tabletop and
floor-standing equipment in order to promote reproducible
results. These guidelines are more explicit than
either CISPR or FCC procedures to date.
The VCCI program has established Japanese
EMI requirements that are comparable to those used
internationally. The wide participation of major
Japanese firms makes this voluntary program essential
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