Operation Manual
<INSTALLATION AND OPERATING PRECAUTIONS FOR TIIS FLAMEPROOF EQUIPMENT>
1
IM 01F06A00-01EN
INSTALLATION AND OPERATING 
PRECAUTIONS FOR TIIS FLAMEPROOF 
EQUIPMENT
Apparatus Certifi ed Under Technical Criteria (IEC-compatible Standards)
1.  General
The following describes precautions on electrical 
apparatus of fl ameproof construction (hereinafter 
referred to as fl ameproof apparatus) in explosion-
protected apparatus.
Following the Labour Safety and Health Laws 
of Japan, fl ameproof apparatus is subjected to 
type tests to meet either the technical criteria for 
explosionproof electrical machinery and equipment 
(standards notifi cation no. 556 from the Japanese 
Ministry of Labour) (hereinafter referred to as 
technical criteria), in conformity with the IEC 
Standards, or the “Recommended Practice for 
Explosion-Protected Electrical Installations in 
General Industries,” published in 1979. These 
certifi ed apparatus can be used in hazardous 
locations where explosive or infl ammable gases or 
vapours may be present.
Certifi ed apparatus includes a certifi cation label and 
an equipment nameplate with the specifi cations 
necessary for explosion requirements as well as 
precautions on explosion protection. Please confi rm 
these precautionary items and use them to meet 
specifi cation requirements.
For electrical wiring and maintenance servicing, 
please refer to “Internal Wiring Rules” in the 
Electrical Installation Technical Standards as 
well as “USER’S GUIDELINES for Electrical 
Installations for Explosive Gas Atmospheres in 
General Industry,” published in 1994.
To meet fl ameproof requirements, equipment that 
can be termed “fl ameproof” must:
(1) Be certifi ed by a Japanese public authority in 
accordance with the Labour Safety and Health 
Laws of Japan and have a certifi cation label in 
an appropriate location on its case, and 
(2) Be used in compliance with the specifi cations 
marked on its certifi cation label, equipment 
name plate and precautionary information 
furnished.
2.  Electrical Apparatus of Flameproof Type 
of Explosion-Protected Construction
Electrical apparatus which is of fl ameproof 
construction is subjected to a type test and certifi ed 
by the Japanese Ministry of Labour aiming at 
preventing explosion caused by electrical apparatus 
in a factory or any location where infl ammable 
gases or vapours may be present. The fl ameproof 
construction is of completely enclosed type and 
its enclosure shall endure explosive pressures in 
cases where explosive gases or vapours entering 
the enclosure cause explosion. In addition, the 
enclosure construction shall be such that fl ame 
caused by explosion does not ignite gases or 
vapours outside the enclosure. 
In this manual, the word "fl ameproof" is applied 
to the fl ameproof equipment combined with the 
types of protection "e", "o", "i", and "d" as well as 
fl ameproof equipment.
3.  Terminology 
(1) Enclosure
An outer shell of an electrical apparatus, which 
encloses live parts and thus is needed to confi gure 
explosion-protected construction.
(2) Shroud
A component part which is so designed that the 
fastening of joint surfaces cannot be loosened 
unless a special tool is used.
(3)  Enclosure internal volume
This is indicated by:— the total internal volume 
of the fl ameproof enclosure minus the volume of 
the internal components essential to equipment 
functions.
(4)  Path length of joint surface
On a joint surface, the length of the shortest path 
through which fl ame fl ows from the inside to outside 
of the fl ameproof enclosure. This defi nition cannot 
be applied to threaded joints.










