Building Control in Japan‐ Part D ‐by HASEGAWA Tomohiro
日本の建築規制 長谷川知弘
Ver. 1910‐ Table of Contents and Abbreviations‐ Part A

Building Control System in General‐ Part B

Background Information‐ Part C

Building Regulatory System‐ Part D Technical Requirements for Building Safety and Amenity(Group A)
Chapter 10

Structural Safety

Chapter 11Fire Safety

Chapter 12

Accessibility

Chapter 13

Energy Conservation

Chapter 14

Other Aspects for Building Safety and Amenity‐ Part E

Technical Requirements from the viewpoint of City Planning (Group B)‐ Part F

Technical Requirements from the viewpoint of Land‐development (Group C)‐ Annexes (under construction)

1

Chapter 10

Structural Safety

10‐1 Composition of the structural codes
10‐2 Structural specifications
10‐3 Structural calculation methods2

10‐1 Composition of the structural codes(1) Basic idea
The basic idea concerning structural safety is that structures must be safe against:(a) permanent load (dead load);(b) imposed load (live load);(c) snow load;(d) wind pressure;(e) seismic force; and(f) Others(2) Concepts
In concrete terms, technical requirements have been set on the basis of the following
concepts:(a) The permanent load and imposed load are safely supported, and cause no excessive
deformation or vibration, which can interfere with the use of the building.
(b) The building does not sustain damage due to a rare medium‐scale snowfall, windstorm,
earthquake, or other event.
(c) The building does not collapse or otherwise fail due to an extremely rare large‐scale
snowfall, windstorm, earthquake, or other event.
3

(3) General Flow of Structural Design(a) Structural Category of the buildings
Every building is classified into one of the categories:‐ Category I (high‐rise buildings);‐ Category II (large‐seized buildings);‐ Category III (medium‐sized buildings); and‐ Category IV (small buildings),
based on the structural type, height, and size of the building, as shown in the table of‘Structural Category of the Buildings’.

4Trends in development of earthquakeresistance measures《Major earthquakes 》
Great Kanto eq.

Niigata eq.
Tokachi Off-shore eq.
Miyagi Off-shore eq.

Great Hanshin-Awaji eq.

Niigata-Chuetsu eq.
West Off Fukuoka eq.

1923

1964
1968
1978

1995

1924
Structural calculation regulation in considering seismic force(First such requirement in the world)
1950
Enactment of the Building
Many buildings built
Standard Law (BSL)
before 1981 do not1971
comply with the current
Amendment of the BSL
1981•Strengthening of RC standards

seismic standard.

Amendment of the BSL(New Seismic Codes)•Not damaged by medium‐scale earthquakes
1995 •Not collapsed by large‐scale earthquakes

Enactment of the Act on Promotion of Seismic Retrofittingof Buildings

2004

1998 •Approval of seismic retrofitting plans
Amendment of the BSL

2005•Building confirmation by private sector, introduction of interim
2006 inspection, performance‐based standards

2007

Off NiigataChuetsu eq.

Noto Peninsula eq.

Iwate-Miyagi Inlandeq.

Iwate North Coast eq.

2008

Great East Japan eq. 2011

Amendment of the Act on Promotion of Seismic
Retrofitting of Buildings•Making a plan for promoting seismic retrofitting by local
government5Structural Category of the Buildings
Categories

Structure, height, and size of building(share) Wooden buildings
Buildings other than wooden buildings
Building height ＞ 60 m
(I) High‐risebuildings (0.1 %)Any of the buildings below other than (I):‐ Building height ＞ 13m, or(II) Large‐sized‐ Steel buildings with 4 or more stories (excluding‐ Eave height ＞ 9m,
Buildings
basement);(2.5%)

other than (I)‐ RC or SRC buildings of 20m or more in height, and‐ Buildings stipulated by the Cabinet Order, such as
steel buildings more than 13 m in height or morethan 9 m in eave height,‐ Number of stories ＞2, or Total floor area ＞200
m2, and‐ Masonry structure, etc. that are more than 13m inother than (I) and (II)(25%)
height and that have eaves of more than 9m inheight.
other than (I) and (II)Buildings other than (I), (II) Buildings other than (I), (II) and (III).
(IV) Smalland (III). It means woodenbuildings
buildings that conform to:(over 70%) ‐ Number of stories ≦2;‐ Total floor area ≦500 m2;‐ Building height ≦13 m; and‐ Eave height ≦9 m.
‐ Number of stories ＞3, or(III) Medium‐2
sized buildings ‐ Total floor area ＞500 m

6

(b) Structural check responding to the Categories
There are 6 structural check combinations (A through F, as shown in the figure ‘Structural
check responding to the Categories’. The order of sophistication of the combinations isfrom A (the highest), down to F.
For each category, the possible combinations to confirm its structural safety are
determined as shown in the figure. It is allowed to use more sophisticated combinations
than the required combination.
Some requirements of structural specifications are not applied to the combinations of A,
B, and C, because these specific requirements can be checked through structural
calculations of A, B, or C. Structural calculation or check for roofing material, etc. is donein the all combinations.

7

Structural check responding to the Categories

B (B or C)

A

only durability, etc.
Time-series
analysis

Performance
evaluation
Ministerial
Approval(III)
Mediumsized(II) Large-sized buildingsh > 31 mh ≤ 31 m(I)
High-rise

Response
and limit
capacity
calculation

C

D

E

(IV)
Small
F

Structural specifications
except someall provisions (which are applied according to theprovisions
structural type of the building)
Structural calculation
Allowable unit stress calculation

Check of Story drift angle
Horizontal loadcarrying capacity
calculation

Check of Stiffness
ratio, Eccentricity
ratio, etc.

Procedures
Check by Designated Structural Calculation Review Bodies
Check by Building Officials / Designated Confirmation and Inspection Bodies

The order of sophistication of the combinations is from A (the highest), down to F. It isallowed to use more sophisticated combinations than the required combination.

8

(i) For Category IV (small buildings), it is required to only comply with structural
specifications. Structural calculations are not required. On the other hand, it isallowed to use other structural combinations. In case where the structural safety ofthe building was confirmed by combinations of A or B, only the structural
specifications on durability, etc. are applied to the buildings.
(ii) For Category II (large‐sized buildings) and Category III (medium sized buildings),
structural calculations are required. As same as Category IV (small buildings), in casewhere the structural safety of the building was confirmed by combinations of A or B,
only the structural specifications on durability, etc. are applied to the buildings.
(iii) For Category I (high‐rise buildings), only the combination A is allowed to use, andperformance evaluation by a Designated Performance Evaluation Body and Approvalby the Minister are required.

9

10‐2 Structural specifications
Structural specifications are provided according to ordinary structural types, namely:‐ wooden structures;‐ masonry structures;‐ reinforced concrete block structures;‐ steel structures;‐ reinforced concrete structures;‐ steel and reinforced concrete composite structures; and‐ plain concrete structures.
In addition, for:‐ special structural methods of ordinary structural types mentioned above (such as wood‐
frame structure); and‐ structural types other than ordinary structural types mentioned above (such as
membrane structure),
structural specifications are established and announced in the form of MLIT Notifications.

10(1) Wooden Structure
Concerning wooden structures, regulations are prescribed for:‐ structure of sills and foundations;‐ size of posts;‐ necessary strength and quantity of braces and structural frames;‐ methods of using joints/connection;‐ quality of preservative measures; and‐ others.
Here, the wooden structure refers to the post and beam structure, which is the conventional
method of construction in Japan (see the next page), while the wood‐frame structure comesunder a different set of structural specifications. Structural specifications also exist for large
wooden structures with posts and beams with large sectional size.

11Structure of Conventional JapaneseＷooden Houses

Source: Structural Engineering Textbook 1995,
Architectural Institute of Japan

12

(2) Masonry Structure
Concerning masonry structures, such as the brick structure and the stone structure,
regulations are prescribed for:‐ foundation structures;‐ necessary length and thickness of walls;‐ wall‐girder structures;‐ limitations on the size of openings;‐ methods of construction work; and‐ others.

(3) Reinforced Concrete Block StructureThis method of construction involves reinforcing bars passing through concrete blocks.
Various regulations are provided for:‐ foundation structures;‐ necessary length and thickness of walls;‐ size and arrangement of reinforcing bars;‐ wall‐girder structures;‐ method of construction work;‐ structural parts of fences; and‐ others.

13(4) Steel Structure
Regulations concerning the steel structure are provided for:‐ effective slenderness ratio of members;‐ foundation structures;‐ methods of making joints and connections; and‐ others.

(5) Reinforced Concrete Structure
Reinforced concrete structures are governed by regulations prescribing:‐ quality of concrete materials;‐ connections and arrangement of reinforcing bars;‐ strength of concrete;‐ method of curing;‐ structure of columns, floor slabs, beams, and bearing walls;‐ depth of concrete cover above steel bars; and‐ others.

14(6) Steel and Reinforced Concrete Composite Structure
Concerning steel and reinforced concrete composite structures, regulations for both steel
structures and reinforced concrete structures are applied correspondingly, as the occasion
demands.

(7) Plain Concrete Structure
Concerning plain concrete structures, regulations for both reinforced concrete structuresand masonry structures are applied correspondingly, as the occasion demands.

(8) Other Structural Types
Technical standards for structural types other than those listed above are announced in the
MLIT Notifications. Some of the technical standards have been announced for:‐ wood‐frame structures;‐ pre‐stressed concrete structures;‐ box‐frame type reinforced concrete structures; and‐ others.
15

10‐3 Structural calculation methods(1) Two‐phase seismic design
Seismic codes revised in 1981 feature a two‐phase seismic design for earthquakes.
(a) Primary seismic design– For medium‐scale earthquake motions (Standard shear coefficient C0 ≥ 0.2)
Strong earthquakes which could occur several times during the life time of thebuilding– Working stress < Allowable stressNot basically changed from the seismic design method before 1981)– For both superstructure and foundation(b) Secondary seismic design– For large‐scale earthquake motions (Standard shear coefficient C0 ≥ 1.0)
Extraordinary earthquakes which could occur once in the life time of the building– It requires additional checking of several aspects of the building that has been
proportioned by the primary seismic design– For superstructure only16

Allowable unit stress calculation and other calculation methods
Size of force
that acts
Medium-scale earthquake
Material
Elastic area
Plastic area
strength

Large-scale earthquake

Range of calculation methods, such as horizontal loadcarrying capacity calculation
Collapse or failure

Allowable
unit stress(Maximum force
that a member
can sustain)

Damage (deformation) will remain even after removal of force.

Relationshipbetween force
working on amember anddeformation

Deformation
Range of allowable unit stress calculation
Original
condition

No damage(structure remains intact)

Original condition will be recovered after removal of force (after earthquake).

17

(2) Allowable unit stress calculation(a) Calculation
Stresses acting upon the sections of elements necessary for structural resistance must be
calculated by the formulas in the following table in cases both:‐ sustained loads (for calculation considering normal time); and‐ temporary loads (for calculation considering snow season, storm, or earthquake).
Kind of force
Force due tosustained loads
Force due totemporary loads

Possible conditions regarding
loads and external forces
Normal time
Snow season
Snow season
Storm
Earthquake

Loads and external forces, whichmust be included
General area Heavy snow area
G+P
G+P
G+P+0.7S
G+P+S
G+P+S
G+P+W
G+P+W
G+P+0.35S+W
G+P+K
G+P+0.35S+K

In this table, G, P, S, W and K represent the following loads and forces:
G: Permanent load (dead load);
P: Imposed load (live load);
S: Snow load;
W: Wind pressure; andK: Seismic force.

18

(b) Confirmation
It shall be confirmed that sustained or temporary stresses do not
exceed the allowable unit stresses in cases both sustained load and temporary load.

Calculated stress ≦ Allowable unit stressValues of allowable unit stress are available for common materials, such as timber, steel,concrete, etc. These values are specified for both sustained loads and temporary loads.
Examples are shown in the next page. “Material strength” mentioned in the table isvalues of strength, which are used for calculations, such as horizontal load‐carrying
capacity calculation.

19

Examples of values of allowable unit stress and material strength
Concrete
Allowable unit stressSustained load

Compression
F/3

Tension
F/30(Values of stress, which are used for allowable unit
stress calculation)

Temporary loads

F/3×2

F/30×2F

F/10

Material strength(Values of strength, which are used for calculations, such as horizontal
load‐carrying capacity calculation)

F represents a specified design strength of concrete (unit: Newton/mm2), which iscompressive strength to be set up in designing, and confirmed by the test of specimens.
Structural stainless steel
Allowable unit stressSustained load

(Values of stress, which are used for allowable unit
Temporary loads
stress calculation)

Compression
F/1.5

Tension
F/1.5

F

F

F

F

Material strength(Values of strength, which are used for calculations, such as horizontal
load‐carrying capacity calculation)

F represents a value of specified design strength (unit: Newton/mm2), which is specified by
20
the Minister according to the kinds and quality of steel, etc.

(3) Loads and External Forces
Loads and external forces as factors for structural calculation vary, depending upon thelocation of the building and its use. Of these forces, at least five must be checked. They are:‐ permanent load (dead load);‐ imposed load (live load);‐ snow load;‐ wind pressure; and‐ seismic force.
Depending upon the conditions, checks must also be performed for other external forces
such as:‐ ground pressure;‐ water pressure;‐ vibration; and‐ shock.

21

(a) Permanent load (Dead load)
The permanent load is the load of each of the components of the building, including
building equipment. It depends on the structural type of the building, finishing material of
the components, etc. Various values are provided in the Enforcement Order for generalcases. For special cases, the permanent load is determined according to the actual
conditions.
(b) Imposed load (Live load)
The imposed load is the load of furniture, occupants, etc. It depends on the use of thebuilding. Various values are provided in the Enforcement Order for general cases. For
special cases, the imposed load is determined according to the actual conditions.

22

(c) Snow load
The snow load is determined by the method of calculation, below. Snow accumulation
varies greatly from region to region in Japan because of the various meteorologicalconditions. Therefore, the Designated Administrative Agencies issue regulations to specify
values, based on criteria specified by MLIT.
S = H・R
S: Snow Load (N/m2)
H: Deepest snow fall in the region (cm), which is specified by regulation, issued by
the Designated Administrative Agency
R: Unit snow load, which is 20 N/m2/cm, or the value specified by regulation, issued
by the Designated Administrative Agency
The snow load used in calculations, however, can be decreased by increasing the degree ofthe roof slope. It can also be decreased in regions where snow is customarily removed
from roofs.

23

(d) Wind pressure
The wind pressure that acts on a building depends on the shape and the height of thebuilding. It is calculated by the velocity pressure multiplied by the wind force coefficient.
The velocity pressure is generally calculated by the following formula:q = 0.6 E Vo2
q: Velocity pressure (N/m2)
E: Coefficient calculated using a method stipulated by the Minister, reflecting theroof height of the building and its surrounding environment
Vo: Standard wind velocity (m/s), as determined by the Minister
Wind force coefficients that are available for general cases are specified in the MLIT
Notification.
(e) Seismic force
The seismic force is determined by calculating the inertial force that is generated throughthe movement of both the ground and the building. That is, horizontal force (seismic shear
force) generated in the building. It is calculated by Formula A and Formula B below,
incorporating the vibration characteristics of the building, the conditions of the ground,and other conditions.

24Formula A: For seismic Force above the ground level
Qi=WiCi
Ci=ZRtAiCo
Qi:
Ci:
Wi:

Z:
Rt:
Ai:
Co:

the seismic shear force of point “i” (the height from groundlevel)
the seismic shear coefficient of point “i”
permanent load added to imposed load above point “i” (+snow load, in heavy snow areas, as designated by the
Designated Administrative Agency)
the seismic zone factor (from 0.7 to 1.0)
vibration characteristic factor
vertical distribution factor
the standard shear coefficient

Wi
Qi

GL

(a) In general cases, not less than 0.2 (not less than 0.3 within areas designated as soft groundareas)(b) For calculating required horizontal load‐carrying capacity, not less than 1.0

Formula B: For seismic force of the below‐ground portion
Qb=WbkQb:k:the seismic shear force
the seismic coefficientk > 0.1 (1‐H/40) z
H = the depth of the portion below ground level (m) (H < 20)z = the seismic zone factor (from 0.7 to 1.0)
Wb: permanent load added to imposed load above the portion25

(4) Structural calculation methods other than Allowable unit stresscalculation
High‐rise buildings and large‐sized buildings must be confirmed to be structurally safe
through structural calculation methods shown in this part.
(II) Large-sized buildingsh > 31 mh ≤ 31 m(I)
High-riseA

B

only durability, etc.

Time-series
analysis

Response
and limit
capacity
calculation(B or C)C(III) Mediumsized
D

Structural specifications
except someprovisions(IV) SmallE

F

all provisions

Structural calculation
Allowable unit stress calculation
Check of Story drift angle
Horizontal loadcarrying capacity
calculation

Check of Stiffness
ratio, Eccentricity
ratio, etc.

The order of sophistication of the combinations is from A (the highest), down to F. It isallowed to use more sophisticated combinations than the required combination.

26

(a) Story drift angle
This is to check that, during a mid‐sized earthquake, the horizontal deformation in eachfloor (cross‐section) is within the scope wherein no external components become
detached and fall from the building (in principle, within 1/200, or 1/120 in cases where
there is no fear of significant damage).

Floor too flexible

Falls

27

(b) Stiffness ratio and Eccentricity ratio
Stiffness ratio
Indicator of balance of hardness oneach floor of building《Vertical diagram》

Damageconcentrated on
weaker floors

Eccentricity ratio
Indicator of balance of horizontal
hardness on each floor《Horizontal diagram》

Deformation concentrated on
specific pillar due to shift inposition

These calculations allow confirmation that the building’s balance is within the scopethat will not result in significant structural weakness28

(c) Horizontal load‐carrying capacity calculation
Qu ≥ Qun Qun =Ds ∙ Fes ∙ Qud
Qu : Horizontal load‐carrying capacity of each story (unit: kilo‐Newtons)
Qun : Required value of horizontal load‐carrying capacity of each story (unit: kilo‐Newtons)
Ds: Structural characteristics factor, considering damping characteristics and ductility ofeach story
Fes: Shape factor, representing stiffness ratio and eccentricity ratio (up to 3.0 for irregularstructure).
Qud: Horizontal force acting upon each story due to seismic force (C0 ≥ 1.0) (unit: kilo‐
Newtons)

②

①

③

hinge

Qu

①

②

③

(stable)(stable)(unstable)

29

(d) Time‐series analysis(i) To continuously clarify forces and deformation in each part of a building under loads
and external forces, such as ground vibration caused by a large‐scale earthquake,through the computer simulations.
(ii) To confirm that forces and deformation clarified in (i) do not exceed the structural
strength and deformation limit of each part of the building.
(iii) To confirm that roofing materials, exterior finishing materials, and curtain walls facing
the exterior are safe from the perspective of structural capacity due to wind pressure,earthquake, and other vibration and impacts.
(iv) Others
Acceleration of the ground
Time

通常の解析
時刻歴応答解析
Ordinary
analysis
Time‐series
analysis（外力の方向と変形が一致）（外力の方向と変形が一致しない場合がある）
Direction of deformation Direction of deformationis always the same as that is not always the same asof external force .
that of external force.

Vibration of the building
Time30

Chapter 11

11‐1
11‐2
11‐3
11‐4
11‐5
11‐6
11‐7

Fire Safety

Composition of the fire codes
Definitions
Fire resistanceFire compartment
External finishing
Internal finishing
Fire evacuation31

11‐1 Composition of the fire codes
The BSL and the Fire Service Law provide various technical requirements to secure fire safety
in buildings. The examples of technical requirements provided by each of the BSL and the Fire
Service Law are shown in the next page responding to the viewpoints of fire safety measures.

32

Technical requirements provided by the BSL and the Fire Service Law
Fire safety measures

Examples of technical requirements
The BSLThe Fire Service Law(Regulates the basic structure (Regulates facilities and equipment
and facilities of buildings)
from a fire safety viewpoint)

Prevention of the spread ‐ Fire‐resistance of roofing
of fire from adjacentmaterials‐ Fire‐resistance of externalbuildings
walls
Prevention of outbreak‐ Fire‐resistance of interior
finishing materialsof fireFire detection
Evacuation
Fire extinguishment andrescuePrevention of spread offire within a building
Prevention of structural
collapse‐ Flame retardant curtains‐ Restrictions on appliances that
operate with a flame‐ Fire alarms‐ Evacuation facilities, such as ‐ Escape facilities, such as escapeescape stairs
ladders‐ Smoke control systems‐ Fire extinguishing equipment,‐ Emergency elevatorssuch as automatic sprinkler‐ Rescue accesssystems and standpipe systems‐ Fire compartments‐ Fire‐resistance of principal
building parts33

11‐2 Definitions
Definitions related to fire safety in the BSL are as below.

(1) Noncombustible materials (hereafter referred to as NC);
(2) Quasi‐ noncombustible materials (hereafter referred to as Q‐NC); and(3) Fire retardant materials (hereafter referred to as FR);are building materials that conform to requirement (*1) during the time range shown in thenext page, and that are either stipulated in the MLIT Notifications or that have been
approved by the Minister on an individual basis.
(*1) Requirement for NC, Q‐NC, and FR
When being heated with the heat of a normal fire, the material must satisfy the essentialconditions in the following items (for those used as external finishing of the building, (a)and (b)) for the time as shown in Table 12 after the beginning of the heating:(a) It must not cause burning.
(b) It must not cause deformation, melting, cracking, or other damage detrimental tofire prevention.
(c) It must not generate smoke or gas that is detrimental to evacuation.
34

NC, Q‐NC, and FR
Duration after Examples of materials deemed to satisfy the requirements forheat is applied NC, Q‐NC or FR‐ Concrete, Mortar, and Lime plaster;‐ Bricks;‐ Pottery tile and Ceramic tile;
20 minutes or‐ Steel and Aluminum;(1) NCmore‐ Glass; and‐ Gypsum board with a thickness of 12 mm or more, and with apaper covering of a thickness of 0.6 mm or less‐ NC;
10 minutes or ‐ Gypsum board with a thickness of 9 mm or more, and with a(2) Q‐NC
more
paper covering of a thickness of 0.6 mm or less; and‐ Wood wool cement board with thickness of 15 mm or more
‐ NC and Q‐NC; and5 minutes‐ Gypsum board with a thickness of 7 mm or more, and with a(3) FRor morepaper covering of a thickness of 0.5 mm or lessMaterial

NC: Noncombustible materials
Q‐NC: Quasi‐ noncombustible materials
FR: Fire retardant materials

35

(4) Parts liable to catch fire are parts of a building within a distance of 3 m for the firstfloor, or 5 m for the second or higher floors, from any of the following:(a) the boundary line with the adjacent land lot;(b) the center line of the road;(c) the center line between exterior walls of two or more buildings on the same site (twoor more buildings with an aggregate total floor area not exceeding 500 m2 are regarded
as one building).
Parts liable to catch fire(see the figure on the right)
However, any part facing an
open space or a water areathat is effective for fire safety,
such as a park, public square,river, or facing walls of fire‐
resistive construction, or the
like, are not considered parts
liable to catch fire.

36

(5) Fire‐resistive buildings are defined as buildings:(a) of which principal building parts (namely, those walls, posts, beams, roofs, and stairways
that are important from the viewpoint of fire prevention):(i) come under fire‐resistive construction (see (6)); or(ii) are constructed using a solution that has been confirmed to be capable ofwithstanding fire and heat until the end of a fire through:‐ Fire‐resistance Verification Method (see 4‐2 (3)); or‐ Approval from the Minister; and(b) of which openings in parts liable to catch fire are equipped with certain fire‐preventive
assemblies.

37

(6) Fire‐ resistive construction is defined as a building part, such as walls, columns,
beams and floors, which conforms to technical criteria of fire‐resistive performance (*1),and:(a) Which uses construction methods established by the Minister (*2); or(b) Which is approved by the Minister (*3).
(*1) Fire‐resistive performance
Technical criteria of fire‐resistive performance are shown in the table of the next page
(with some other requirements). Building parts of fire‐resistive construction must not be
deformed, melted, cracked, or undergo any other damage detrimental to structuralresistance during the times as listed in the table after the heating begins, when they areheated with heat produced by a normal fire.
(*2) Construction methods established by the Minister
Common construction methods of building parts of fire‐resistive construction have been
specified by the Minister. They are deemed to have fire‐resistive performance during thetimes as listed in the table. Their examples of reinforced concrete structure are shown in
the table of the page after the next.
(*3) Approval by the Minister
Other than the common construction methods, construction methods of building parts,
which the Minister approved that they have fire‐resistive performance, may be used as
fire‐resistive construction.
38

1

Technical criteria of Fire‐resistive performance required(1) on the building parts of fire resistive construction

4
5

(2)

14
15

(3)

(1)
Story Uppermost story
and second to
fourth stories
from theParts
uppermost story(2)
Fifth tofourteenth
stories from theuppermost
story

(3)
Fifteenth story
or more fromtheuppermost
story

Load
bearingwalls

1 hour2 hours

2 hours

Columns

1 hour2 hours

3 hours

Floors1 hour2 hours

2 hours

Beams

1 hour2 hours

3 hoursRoofs

0.5 hour

Stairs

0.5 hour39

Example of building parts of fire‐resistive construction (in case of reinforced concrete
structure)
In case of steel structure, fire‐preventive covering is required.
Requiredtimes (*)

Required conditions, such as depth of concrete cover above steel bars

Load bearing
walls

60

B≧ 70 mm, t≧30 mm

120

B≧100 mm, t≧30 mm

Columns60

t≧30 mm120

B≧250 mm, t≧30 mm

180

B≧400 mm, t≧30 mm

60

B≧ 70 mm, t≧20 mm

120

B≧100 mm, t≧20 mm

60t≧30 mm120

t≧30 mm180

t≧30 mm

Floors
Beams

Roofs

30

Stairs30

Roof covered withconcrete finish

RC structure
RC structure

Steel structure(*) Minutes, which are required on each building part (See the preceding page.)40

(7) Quasi fire‐resistive buildings are defined as buildings:(a) of which construction method meets any of following:(i) Principal building parts come under quasi fire‐resistive construction
Type of quasi fire‐resistive construction (see Figure of Type A)
Type of 1‐hour quasi fire‐resistive construction(ii) Buildings are constructed using a construction method specified in the MLIT
Notification.
Type of fire‐resistive external walls (see Figure of Type B‐1)
Type of NC (Noncombustible materials) (see Figure of Type B‐2)(iii) Buildings are constructed through a solution approved by the Minister.
Type of Ministerial approvaland(b) of which openings in parts liable to catch fire are equipped with certain fire‐preventive
assemblies.
Remark: The definition of quasi fire‐resistive buildings does not include fire‐resistive
buildings.

41

Quasi fire‐resistive building
Type of quasi fire‐resistive construction (Type A)
Remarks:(1) NC: Noncombustible material(2) Q‐NC: Quasi‐noncombustible
material(3) Time shown in the figuresindicates the duration of time forwhich components of quasi fire‐
resistive buildings must be able
to withstand fire.

42

Quasi fire‐resistive building
Type of fire‐resistive external
walls (Type B‐1)

Type of NC (Noncombustible
materials) (Type B‐2)

43

(8) Fire‐protection Zone and Quasi Fire‐protection Zone are zoning systems
provided by the City Planning Law. These zones are designated in urban areas in order toprevent the spread of fire from building to building. In the major cities of Japan, these zones
are designated over a large area. Extensive measures for fire safety are required in thedesignated zones by the BSL.

(9) Zone based on Article 22 are the urban areas designated by the DesignatedAdministrative Agencies, based of Article 22 of the BSL for the purpose of prevention of the
spread of fire in urban areas.
Zone based on Article 22
Quasi Fire‐protection Zone

Quasi
Fire‐protection
Zone

Fire‐Protection Zone

Railroad

Station44

11‐3 Fire resistanceIn order to:‐ secure the time for evacuation,‐ prevent collapse, and‐ prevent catching fire,
fire resistance is required on buildings from three characteristics of buildings as follows:(1) Scale of the buildings;(2) Use of the buildings; and(3) Location of the buildings.

45

(1) Restrictions on Large‐scale Buildings
In case of buildings,(i) which are more than 13 m in building height, more than 9 m in eave height, or morethan 3000 m2 in total floor area, and(ii) of which bearing walls, posts, or beams are made of combustible materials, such as
wood and plastic,
their safety of fire resistance must be confirmed by:(i) using materials that the Minister approved as fire‐resistive construction; or(ii) using solution that has been confirmed to be capable of withstanding fire and heat
until the end of a fire through:‐ Fire‐resistance Verification Method (see 4‐2 (3)); or‐ Approval by the Minister.
Some construction methods, of which structural members are wood covered by gypsum
boards, have been approved by the Minister as fire‐resistive construction, which isconsidered to be able to undergo the fire for one hour.

46

(2) Restrictions on Construction of Special Buildings
Special buildings are defined as, but not limited to:(a) buildings that are intended to be used by many and unspecified people, such as
theaters, grandstands and department stores; and(b) as buildings where many people sleep, such as apartment houses, hotels and hospitals.
It is prescribed that certain sizes of these special buildings must be fire‐resistive buildings,
and other certain sizes of these special buildings must be either fire‐resistive buildings orquasi fire‐resistive buildings. (see the following four pages)

47

Fire Resistance of Special Buildings (1/3)
Grade of building
required

Fire‐resistive building(in case of (1) or (2))
(1)
(2)

Use
‐Theaters
The main floor is‐ Movie theaters
not on the 1st floor‐ Entertainment halls
1‐Grandstands
Third or higher‐Public halls
floors is used for‐ Assembly halls
any of these uses.
‐Hospitals‐Clinics (limited to thosehaving patient
The third floor or
accommodation facilities )higher is used for
2 ‐Hotels/inns
any of these uses.
‐Boarding houses(*2)‐Apartment houses‐Dormitories‐ Welfare facilities(*1)

Fire‐resistive building
or Quasi fire‐resistive
building

Seating space is
200 m2 or more.
(In case of open‐
air stand, 1,000
m2 )

‐

‐

Floor area for the useon the 2nd floor is
300 m2 or more. (Forhospitals, this only
applies to buildings
which have patientaccommodation
facilities on the 2nd
floor.)
48

Fire Resistance of Special Buildings (2/3)
Grade of building
required

Fire‐resistive building(in case of (1) or (2))(1)(2)

Fire‐resistive building
or Quasi fire‐resistive
building

Use‐ Schools‐ Gymnasia
The third floor‐ Museums, Art museums
The total floor areasor higher is used
3 ‐ Libraries‐
for the use is 2,000
for any of these‐ Bowling alleys, Indoor ski slopes,
m2 or more.
uses.
Skating rinks, Swimming pools,
Sports practice facilities‐ Department stores, Markets‐ Exhibition halls‐ Cabarets, Cafes, Night clubs,
Bars, Dance halls, Amusement
The third floor
The total floor
halls
The floor area for theor higher is used areas for the
4 ‐ Public bathhouses
use on the 2nd floor
for any of these use is 3,000‐ Machiai, Restaurants, Dining
is 500 m2 or more.
2
uses.
m or more.
facilities,‐ Stores engaged in commodity
sales (excluding those with afloor area of 10 m2 or less)49

Fire Resistance of Special Buildings (3/3)
Grade of building
requiredUse
5 ‐ Warehouses‐Automobile garages‐Automobile repair shops
6‐Movie studio‐ Television studio‐ Storage or treatment
facilities for hazardous
7
materials of more than aspecified value

Fire‐resistive building
Fire‐resistive building or(in case of (1) or (2))
Quasi fire‐resistive(1)(2)
building
Total floor areas
Total floor areas forfor the use on the‐the use is 1,500 m2 or
3rd floor or higher
more.
is 200 m2 or more.
The third floor
Total floor areas foror higher is used‐
the use is 150 m2 orfor any of these
more.
uses.
‐

‐

All cases50

(*1) Welfare facilities include:‐ childrens’ welfare facilities;‐ maternity clinics;‐ rehabilitation facilities for physically disabled persons (excluding prosthetic appliances
manufacturing facilities and information centers for the visually/hearing impaired);‐ social rehabilitation facilities for mentally disordered persons;‐ protective institutions (excluding medical protective institutions);‐ protective facilities for women;‐ facilities for people with intellectual disabilities;‐ welfare facilities for the elderly;‐ fee charging homes for the elderly; and‐ maternal and child health facilities.
(* 2) Three‐story apartment houses can be of quasi fire‐resistive construction when all of thefollowing conditions exist:‐ the area is not in a Fire Protection Zone;‐ the structure has 1‐hour or more quasi fire‐resistive performance; and‐ all other necessary measures are implemented from the viewpoint of fire prevention.

51

(3) Restrictions on buildings in Fire‐protection Zones and Quasi Fire‐
protection Zones
Buildings in Fire‐protection Zones or Quasi Fire‐protection Zones must follow therequirements as shown in the following two pages.
<Exceptions> Small annexed buildings, etc. are exceptions.
If buildings are located in either Fire‐protection Zones or Quasi Fire‐protection Zones,
openings located in parts liable to catch fire must be fitted with certain fire‐preventive
assemblies.

52

Restriction on Buildings in Fire‐protection Zone

4

Number ofstories

Fire‐resistive building

3
2
1
0

Fire‐resistiveor
Quasi fire‐resistive
building
100m2

Total floor area
53

Restriction on buildings in Quasi Fire‐protection Zone

Fire‐resistive building
Number of
Stories4

Basements are
excluded from thenumber.

3*1

2

Fire‐resistive or
Quasi fire‐resistive
building

*2
1
0

500

1500

m2

Total Floor Area
*1:Fire‐resistive building, Quasi fire‐resistive building, building stipulated in Article 136‐2 ofthe BSL Enforcement Order*2:Fire preventive construction for the external walls and soffits liable to catch the fire ofwooden buildings54

11‐4 Fire compartment
Fire‐resistive buildings, etc. must be separated into fire compartments with, but not limitedto:(a) floors or walls of fire‐resistive construction, etc.; and(b) fire doors.
These fire compartments have the following categories.

(1) Area separations
Area separations are arranged to prevent the horizontal spread of fire within a building.
They have walls and floors of fire‐resistive construction, fire doors, and so on. (see thefollowing three pages)
In addition, wooden buildings with a floor area of more than 1,000 m2 must be effectively
divided with fire walls into areas of no more than 1,000 m2, unless they are fire‐resistive
buildings or quasi fire‐resistive buildings.

55

a. Maximum
allowable
floor area of each
Area Separations depending on fire resistanceof thebuilding
Buildings/parts of buildings

Buildings whose principal building parts are offire‐resistive construction
Voluntary Quasi sire‐resistive
buildings

Quasi
fire‐
resistive
buildings

Obligated
Quasi fire‐
resistive
buildings

fire compartment
b. Methods of separation
a. 1,500 m2 (*1)
b. Floors and walls: 1‐hour quasi fire‐
resistive construction
Openings: Specified fire‐preventive
assembly (*2)
a. 1,000 m2 (*1)
b. Ditto (*2)

‐ Type of 1‐hour quasi
fire‐resistive
construction‐ Type of NC‐ Type of quasi fire‐a. 500 m2 (*1)
resistive construction b. Floors and walls: 1‐hour quasi fire‐‐ Type of fire‐resistive
resistive construction
external walls
Openings: Specified fire‐preventive
assembly
Partition walls: Partition walls in the key
locations are of quasi fire‐resistive
construction. (*3)

Remark: Each type of Quasi fire‐resistive buildings are explained in 6‐2.
56

Relaxation (*1):‐ In cases where automatic fire extinguishing equipment (such as sprinklers) is provided,
the maximum allowable floor area of each fire compartment can be doubled.
Exceptions (*2):‐ Seating space in theaters, movie theaters, entertainment halls, grandstands, public halls,
assembly halls, and space for gymnasia, factories, etc.
‐ Staircases, hoistways (elevator shafts) including passenger lobbies partitioned toconstitute fire compartments.
Exceptions (*3):‐ Space for gymnasia, factories, etc. with NC or Q‐NC for interior finishes.
‐ Staircases or hoistways (elevator shafts) including passenger lobbies with NC or Q‐NC forinterior finishes partitioned to constitute fire compartments.

57

Area Separations for high‐rise buildingsa. Maximum allowable floor area of each fire
Buildings/parts of buildings
compartment (*1)
b. Methods of separation
11th floor,
Interior finish and base a. 500 m2
or higher
lined with NC
b. Floors and walls: Fire‐resistive construction
Openings: Specified fire‐preventive assembly (*2)
Interior finish and base a. 200 m2
lined with Q‐NC
b. Ditto (*2)
Other than above
a. 100 m2
b. Floors and walls: Fire‐resistive construction
Openings: Fire‐preventive assembly (*2)
Relaxation (*1):‐ In cases where automatic fire extinguishing equipment (such as sprinklers) is provided, themaximum allowable floor area of each fire compartment can be doubled.
Exceptions (*2):‐ Staircases and hoistways (elevator shafts) including passenger lobbies, corridors or otherevacuation spaces, or housing units in apartment houses not exceeding 200m2, wherethese are partitioned to provide fire compartments.
58

(2) Shaft enclosures
Vertical spaces, such as staircases, hoistways (elevator shafts), pipe spaces, wellholes, etc.
that pass through two stories or more, must be, in principle, separated from other spaces
with:(a) floors or walls of quasi fire‐resistive construction; or(b) fire‐preventive assemblies as stipulated in Article 2 Item (9‐2) (b) of the BSL.

(3) Mixed‐use separations
In special buildings (see 6‐3) of complex uses, parts of different use categories must be
separated from each other with:(a) floors or walls of 1‐hour quasi fire‐resistive construction; or(b) specified fire‐preventive assemblies defined in Article 112 paragraph 1 of the
Enforcement Order.

59

11‐5 External finishing
In order to prevent buildings from catching fire, restrictions are placed on external finishes forroofs, soffits, external walls, and openings.

(1) Fire prevention restrictions for roofs
For buildings which:(a) have a total floor area in excess of 1000 m2 ; or(b) are located in certain areas (Fire‐protection Zones, Quasi Fire‐protection Zones, or Zones
based on Article 22),
roofs must be made in such a way that they do not catch fire, melt, or undergo splitting, etc.
from sparks caused by fires.

60

(2) Restrictions for external walls and soffits located in parts liable to catch
fire
External walls and soffits of wooden buildings located in parts liable to catch fire must be offire‐preventive or quasi fire‐preventive construction, for example, walls that are finished withmortar or laminated with gypsum board, in accordance with:‐ the use of the building;‐ the total floor area; and‐ the zone in which it is located.
(see the next page)
Remarks:
If a building stands in two (or more) of the above zones, the stricter (or strictest) provisionsof the restrictions in the zones are applied to the whole building.

61Fire‐preventive construction of parts liable to catch fire on the external walls and soffits ofbuildings, such as wooden buildings
Areas
In Quasi Fire‐
protection
Zones
in the Areas
based on
Article 22 of
the BSLAll areas

Building type

Parts
Construction
External walls andFire‐preventive
soffits in parts liable
All buildings
construction
to catch fireExternal walls and Fire‐preventive
1 Schools, theaters, movie theaters,
entertainment halls, grandstands, public halls, soffits in parts
construction
assembly halls, markets, or public bathhouses liable to catch fire
2 Automobile garages (only applied in cases
where aggregate of floor areas for the said
use exceeds 50 m2)
3 Department stores, apartment houses,
dormitories, hospitals, or warehouses (onlyapplied in cases where the number of stories
is two and the total floor area for the said use
exceeds 200 m2)
External walls in
Structure
4 Other uses
parts liable to catch satisfying quasi
fire‐preventive
fire
performance
Fire‐preventive
Buildings whose total floor area (aggregate ofExternal walls andtotal floor areas in case of 2 or more wooden
construction
soffits in parts liablebuildings on the same site) is more than 1,000
to catch firem2

62

11‐6 Internal finishing
Finishing materials for ceilings and walls of the buildings are restricted in accordance with
their:‐ use;‐ scale;‐ construction types; and‐ etc.
for the purpose of retarding the initial growth of fire, ensuring safe evacuation in the initialstage of fire, for instance, controlling the amount of smoke generated with the spread of fire,so as not to obstruct the way for evacuation.
The ceilings and walls of buildings subject to those restrictions must be finished, according tofire safety properties required of the part concerned, with:‐ NC (noncombustible materials);‐ Q‐NC (quasi‐noncombustible materials); or‐ FR (fire retardant materials).
(see Annex 3)63

11‐7 Fire evacuation
Codes relating to the arrangement and the specification of evacuation measures such as:‐ escape stairs;‐ smoke exhaust equipment;‐ lighting apparatus for emergency use;
‐ entrances for emergency use;
‐ elevatory equipment for emergency use;
‐ etc.
are provided in order to safely evacuate people to ground or to back up fire fighting andrescue.
Where evacuation safety has been verified using Verification Method for Evacuation Safety,
etc., some Specific Provisions may not be applied to the building. (see 4‐2(4))

64(1) Through Stairs (Direct Stairs)
For prompt escape from upper floors or from the basement, through stairs, which connect
directly to the evacuation floors that have exits to the ground, must be provided in such a
way that the walking distance from any part of the rooms to the through stairs be within acertain distance.
Furthermore, large buildings or certain special buildings must have two or more throughstairs for emergency, in case when one of them cannot be used. In this case, two or morestairs must be arranged as well as can be so that people can escape in different directions.
(The overlap of the walking distances leading to the two or more through stairs must not be
more than half of the length of the required walking distance.)65

(2) Escape Stairs and Special Escape Stairs
In:‐ high‐rise buildings;‐ buildings with basement floors; or‐ buildings used by many people, such as department stores;
ordinary through stairs may not be enough to ensure safe evacuation. So, such buildings
must have escape stairs or special escape stairs that have safer performance against fire andsmoke than ordinary through stairs. (see the next page)66

Escape Stairs (Example)
Outside of the building
Return wall
Smoke
500
mm
or
more

Special Escape Stairs (Example)

No influence ofsmoke
900 mmor widerEvacuation direction
Smoke

Inside of the building
Fixed window

Room

Room

Corridor

Inside ofthebuilding

minutes fire shielding
performance

Window openable
toward the out side

750 mmor moreWindow must be a fireprotective assembly having
20-minutes fire shielding
performance, be fixed, andhave an open area of lessthan 1 m2.

Fire-protective
assembly having 20-

Fire-protective
assembly having 20minutes fireshielding
performance

Specified fire-protective
assembly having 60-minutes
fire shielding performance

Outside of thebuilding67

(3) Exits on the Evacuation Floor
Regarding the evacuation floors, there is a limit to the walking distance both:‐ from a room to the exits; and‐ from through stairs to the exits.

(4) Passageways within a Building‐site
A passageway within the building‐site must be provided from an exit to an open space, suchas a roadway, park or public square. This passageway must have a width of 1.5 m or more (3m or more, in principle, in the case of large wooden buildings).

(5) Smoke Exhaust Equipment
Smoke exhaust equipment must be provided in special buildings and large buildings in order
to effectively eliminate smoke and gas generated from combustible materials, thus ensuringa safe evacuation.

(6) Lighting Apparatus for Emergency Use
Lighting apparatus for emergency use must be provided according to the size of buildings, inorder to ensure safe evacuation during a power failure.

68(7) Elevatory Equipment for Emergency Use and Entrances for Emergency
Use
Buildings with a height exceeding 31 m must, in principle, have elevatory equipment for
emergency use for fire fighters. Also buildings must be provided with emergency entrances(elevator equipment, a balcony, or a window through which fire fighters can enter thebuilding) on every floor, beginning with the third floor, up to 31 m in height, so that rescue
work and fire fighting activities can be carried out smoothly.

69

Chapter 12

Accessibility

See Chapter 7 of Part C.

70

Chapter 13

Energy Conservation

Under construction

71

Chapter 14

14‐1
14‐2
14‐3
14‐4
14‐5

Other Aspects for Building Safety and Amenity

Building sites
Environmental sanitation
Structure of stairway
Building equipment
Structures and amusement facilities72

14‐1 Building sites(1) Ground level
Ground level of a building site must be higher than the border of adjacent roads andadjacent land lots, in principle.

(2) Improvement of ground
Fills, an improvement of ground or other measures necessary for sanitation or safety must
be taken if necessary.

(3) Drainage
Sites of buildings must have proper sewer pipelines, sewer channels, manholes andother facilities for the purpose of draining and disposing of rainwater and wastewater.

(4) Countermeasures against landslides
If buildings are likely to be damaged by landslides, etc., construction of retaining walls orother appropriate measures for safety must be taken.

73

14‐2 Environmental sanitation(1) Natural Lighting of Habitable Rooms
A habitable room is a space that is continuously used for living, working, meetings,
amusement, and so on, and that includes a living room or bedroom in a house, an officeroom, a meeting room, a theater auditorium, a hall, etc.
Requirements for natural lighting are prescribed from the viewpoint of environmental
sanitation. The following habitable rooms must, in principle, have windows and otheropenings for natural lighting, and the ratio of the effective area thereof to the floor area
must be more than a specified ratio for, but not limited to, the following spaces:‐ habitable rooms in houses;‐ classrooms in schools;‐ wards in hospitals or clinics;‐ guestrooms in boarding houses; and‐ sleeping areas in dormitories.

74Calculation of “effective natural lighting”(a) Opening section area in habitable room x Lighting correction factor(b) Floor area of habitable room x 1/7 (1/7: In case of a residence)(c) Confirmation of (1)≧(2)
lighting correction factor
A lighting correction factor is determined by the height of the opening section and the
distance from the border with the neighboring land, etc. The figure increases if the opening
section is higher or the border is farther.
Oblique line of lighting(10/4: in case ofresidential zones)

Lighting correction factor inaccordance with the d/h ratio

The lighting correction factor ofthis window is 0.8.

Adjacent site75

(2) Ventilation of Habitable Rooms
Ventilation equipment must be installed in:‐ habitable rooms in theaters and movie theaters; and‐ rooms having equipment that uses a flame, such as kitchens, bathrooms, etc.
There is another requirement of installation of mechanical ventilation equipment for
habitable rooms as a countermeasure against chlorpyrifos emitted from furniture, etc. (see
(3))

76

(3) Countermeasures against Sick Building Issue
There are some requirements in order toprevent harm to human health by thescattering of asbestos or by emissions ofother harmful substances from buildings
materials.
(a) It is prohibited to add asbestos tobuilding materials.

Influence to humanhealthFormaldehyde
and others

Ant Preventing substances(b) It is prohibited to use the following building materials:‐ sprayed asbestos; and‐ sprayed rock wool that contains more than 1 % in weight of asbestos;
excluding those approved by the Minister as those do not cause the scattering or
emission of asbestos particles.
(c) In a building with habitable rooms,‐ It is prohibited to use building materials that might emit chlorpyrifos, an insecticide fortermites;‐ It is restricted to use of building materials that might emit formaldehyde; and‐ It is required to install mechanical ventilation equipment, except in traditional wooden
houses that have lower air tightness.
77

(4) Others
The following regulations are also provided with respect to the environmental sanitationand safety in the daily use of buildings.
(a) Height of the ceilings of habitable rooms
The height of the ceilings of habitable rooms must be 2.1 m or more (on average in eachroom).
(b) Height of floors from the ground and methods of damp proofing in habitable rooms
In principle, the first floor of wooden buildings must be 45 cm high, from the ground, or
more, and must be provided with ventilation under the floor.
(c) Sound blocking of the separation walls
Separation walls between each unit of row houses or apartment houses must be of astructure that has effective sound insulation.

78

14‐3 Structure of stairway
Some regulations are provided for stairs and for slope‐
ways (*) from the viewpoint of ensuring safety in daily
situations.
(*) If a slope‐way is provided as an additional exit route,and therefore not required in the BSL, theseregulations are not applied to such slope‐ways.

Tread

Riser

(1) Size of width, riser and tread of stairway
Type of stairway
Stairway for children in elementary
schoolStairway in junior high school, high school,
store, theatre, movie theatre or otherpublic facilities
Stairway in residence (excluding public
space in housing complex)

Width of stairway
and landing

Riser

Tread

≧140 cm≦16 cm≧26 cm≧140 cm≦18 cm≧26 cm≧75 cm≦23 cm≧15 cm79

(2) Handrails
A stairway is requited to have handrails. In case either side of stairway and landing has nohandrail, it is required to install a side wall.

(3) Landings
Concerning stairway in elementary, junior high or high school, department store, theatre, etc.
it is required to build a landing for every 3m height or less in case the height of the stairway
exceeds 3m. For other cases, it is required to build a landing for every 4m height or less.

(4) Slope‐ways
The slope of slope‐ways in place of stairs must not exceed 1/8.

80

14‐4 Building equipment(1) Sewage(a) In regions where wastewater can be treated at a final disposal plant, it is required to haveflush toilet for which sewage pipes are directly connected to the sewage system.
(b) In case of discharging waste from toilet to other than the sewage system, it is required to
install a septic tank. In areas other than districts planned for sewage treatment, it must
be a combined septic tank (a combined kitchen waste and toilet sewage treatment tank)as per the Purification Tank Act.

81

(2) Plumbing Facilities (Water Supply and Drainage)(a) Sanitary criteria for plumbing facilities‐ Not to directory connect plumbing facilities for drinking water and other plumbing
facilities.
‐ To install drain traps, etc. For plumbing facilities for drainage.
(b) Criteria for plumbing facilities in general (It is necessary to design plumbing facilities
considering different aspects such as structure, fire prevention and hygiene.)‐ To avoid a piercing arrangement that would cause a problem in the aspect of structuralload‐bearing capacity.
‐ To take countermeasure against corrosion according to the material in case there is arisk of corrosion, such as being buried in concrete.
‐ To use incombustible materials for duct, dust chute, etc. in case of being installed in athree‐story or higher building.

82

(3) Elevatory equipment
Elevatory equipment must be constructed for safe operation. In addition, hoistways mustnot become channels for the spread of fire.
Elevatory equipment installed in buildings is classified into the following:(a) Elevators: elevatory equipment (*) that:‐ transports people;‐ transports people and articles; or‐ transports articles, whose cage has a horizontally projected area exceeding 1 m2, andwhose ceiling height exceeds 1.2 m.
(*) excluding escalators(b) Escalators(c) Elevatory equipment exclusively for small objects: elevatory equipment used totransport articles, and whose cage has a horizontally projected area of 1 m2 or less, andwhose ceiling height is not more than 1.2 m.
The requirements for each items are as shown in the next page.
For special elevators, such as elevators in a dwelling, some requirements are replaced by the
Ministerial notification.

83

(a) Elevators
Cages and principal structural parts of elevators (parts to support or suspend cages) must
either:‐ meet the construction methods specified by the Minister; or‐ have their safety confirmed through the elevator strength verification method; or‐ be constructed by a construction method approved by the Minister.
Requirements on other parts, such as drive units, machine rooms, and safety devices, arealso provided.
(b) Escalators
The slope must be no more than 30 degree. The width of the steps must be no more than
1.1 m. Steps and principal structural parts of escalators (parts to support or suspend
steps) must either:‐ meet the construction methods specified by the Minister; or‐ have their safety confirmed through the escalator strength verification method; or‐ be constructed by a construction method approved by the Minister.
Requirements on other parts, such as drive units, trapping prevention systems, andhandrail structures, are also provided.
(c) Elevatory equipment exclusively for small objects
The regulations for elevators are partially applied, as necessary.

84

14‐5 Structures and amusement facilities
The BSL applies to:(1) Structures, such as:(a) chimneys exceeding 6 m in height (including any supporting frame or stay wire, but
excluding stove chimneys);(b) advertisement towers, advertisement billboards, decorative towers, and memorial
towers exceeding 4 m in height;(c) elevated water tanks, silos, and observation towers exceeding 8 m in height; and(d) retaining walls exceeding 2 m in height.
(2) Amusement Facilities, such as:(a) elevated amusement facilities such as water chutes, and roller coasters; and(b) rotating amusement facilities that use motors such as merry‐go‐rounds, Ferris wheels,
octopus rides, and aero‐towers.
The BSL and its related documents provide requirements for the abovementioned in order tosecure safety.

85