Reference number  
DRS 186 -5: 201 8 
© RBS yyyy  
  
 RWANDA 
STANDARD  DRS 
186-5 
 
Second e dition  
 
Code of practice for fire safety  
of building — 
Part 5: 
Exit requirements and personal hazard  CD RS 186-5:2013  
 
 
ii Error! Reference source not found.  
  DRS 186 -5: 201 8 
iii                 ©RSB 2018 All rights reserved  
 
 In order to match with technological development and to keep continuous progress in industries, 
Standards are  subject to periodic review. Users shall ascertain that they are in possession of the latest 
edition  
 
 
 
 
 
 
 
 
 
 
© RSB 2018 
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized 
in any form or by any mean s, electronic or mechanical, including photocopying and microfilm, without 
prior written permission from R SB. 
Requests for permission to reproduce this document should be addressed to  
Rwanda Standards  Board  
P.O Box 7099 Kigali -Rwanda  
Tel. +250 252 586103/5 82945  
E-mail: info@rsb.gov.rw  
Website: www.rsb.gov.rw  DRS 186 -5: 201 8 
©RSB 2018 All rights reserved                  iv 
 
 Contents  Page 
Foreword  ................................ ................................ ................................ ................................ .............................. v 
1 Scope  ................................ ................................ ................................ ................................ ...................... 1 
2 Normative references  ................................ ................................ ................................ ............................ 1 
3 Exit Requirements  ................................ ................................ ................................ ................................ .1 
3.1 General  ................................ ................................ ................................ ................................ .................... 1 
3.2 Types of exits  ................................ ................................ ................................ ................................ ......... 2 
3.3 Occupant load  ................................ ................................ ................................ ................................ ........ 2 
3.4 Arrangement and capacity of exits  ................................ ................................ ................................ ......3 
3.5 Number of exists  ................................ ................................ ................................ ................................ ....5 
3.6 Doorways  ................................ ................................ ................................ ................................ .............  13 
3.7 Corridors and passageways  ................................ ................................ ................................ ..............  13 
3.8 Internal staircases  ................................ ................................ ................................ ..............................  14 
3.9 Fire escapes or external stairs  ................................ ................................ ................................ ..........  15 
3.10  Spira l fire escape  ................................ ................................ ................................ ................................  15 
3.11  Roof exit  ................................ ................................ ................................ ................................ ...............  16 
3.12  Fire tower  ................................ ................................ ................................ ................................ .............  16 
3.13  Ramps  ................................ ................................ ................................ ................................ ..................  16 
 DRS 186 -5: 201 8 
v                 ©RSB 2018 All rights reserved  
 
 Foreword  
Rwanda Standard s are prepared  by Technical Committees and approved by R wanda Standards Board (RSB) 
Board  of Directors in  accordance with the procedures of RSB, in compliance with Annex 3 of the WTO/TBT 
agreement on the preparation, adoption and application of standards.  
The main task of technical committees is to prepare national standards.  Final Draft Rwanda S tandards 
adopted by Technical committ ees are ratified by me mbers of RSB Board of Director s for publication and 
gazettment as Rwanda Standards.  
DRS 186-5 was prepared by Technical Committee RSB/TC 28, Fire safety of building  — Code of practice : 
In the preparation of this standard, reference was made to the following standard : 
IS 2189:2008; Selection, installation and  maintenance of automatic fire detection and alarm system - Code of 
practice   
The assistance delivered from the above source is hereby acknowledged with thanks.  
This second edition cancels and replaces the first edition (RS  186-5: 2013) of which has been t echnically 
revised . 
DRS 186 consists of the following parts, under the general title Fire safety of building  — Code of practice : 
Part 1: General principles of fire grading and classification  
Part 2: Details of construction  
Part 3: Fire safety in public buildings  
Part 4: Selection, installation and maintenance of automatic fire detection and alarm system  
Part 5: Exit requir ements and personal hazard  DRS 186 -5: 201 8 
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Committee membership  
The following organizations were represented on the Technical Committee on Fire safety (RBS/TC 28) in the  
preparation of this standard.  
City of Kigali  
College of Science and Technology  
CABLELINE  
Energy Util ity Corporation Limited  
ELECTRICOM  
ISCO  
Institute of Engineers Rwanda  
Ministry of Disaster Management and Refugees  
Ministry of Infrastructure  
Rwanda Housing Authority (RHA)  
Rwanda Motor Ltd  
Rwanda National Police  
REAL  
Société Rwandaise d’Assurance (SONARWA )  
SONATUBES  
Rwanda Standards Board (RSB) - Secretariat  DRS 186 -5: 201 8 
vii                 ©RSB 2018 All rights reserved  
 
  DRS 186 -5: 201 8 
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 Code of practice for fire safety of building ― Part 5: Exit 
requirements and personal hazard  
1 Scope  
This standard covers requirements regarding fire safety of buildings with respect to exit requirem ents and 
personal hazard.  This standard is applicable to all types of buildings  
2 Normative references  
The following referenced documents are indispensable for the application of this document. For dated 
references, only the edition cited applies. For undat ed references, the latest edition of the referenced 
document (including any amendments) applies.  
DRS 186 -1; Code of Practice for Fire Safety of Building  — Part 1: General Principles of fire grading and 
classification  
DRS 186 -2, Fire safety of building  — Code of practice Part 2: Details of construction  
RS ISO  7010; Graphical symbols — Safety colours and safety signs — Safety signs used in work places and 
public areas  
3 Exit r equirements  
3.1 General  
3.1.1 Ample provision for escape of population of a building whe n on fire is vital and all routes should be 
constructed to ensure that the popula tion reaches a place of safety in the shortest period of time without 
undue hindrance by smoke, fumes, debris and the like.  
3.1.2 Every building meant for human occupancy shou ld be provided with sufficient exits, with adequate 
signage complying with RS ISO 7010 , to permit safe escape of occupants in case of fire or other emergency.  
3.1.3 In every building, exits should comply with the minimum requirements except those not acces sible for 
general public use.  
3.1.4 All exits should be free of obstructions.  
3.1.5 No building should so altered as to reduce the number, width or protection of exits to less than that 
required.  
3.1.6 Exits should be clearly visible and the routes to reac h the exit should be clearly marked and sign 
posted to guide the population of the floor concerned. Signs should be painted with illuminated paint.   
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 NOTE  This provision should not apply to R-2 and R-4 occupancies up to 15  m in height  
3.1.7 Adequate and rel iable illumination should be provided for exits.  
3.1.8 Fire check doors  should at appropriate places along the escape routes to prevent spread of fire and 
smoke ,particularly at the entrance to lifts and stairs where a ‘funnel or flue effect’ may be created , including an 
upward spread of fire.  
3.1.9 All exits should provide continuous means of access to the exterior of a building or to an exterior open 
space leading to a street.  
3.1.10  Exits should be so arranged that they may be reached without passing thro ugh another occupied unit.  
3.2 Types of e xits 
3.2.1 An exit may be a doorway, a corridor or passageway(s) to an internal staircase, ramps or external 
staircase, or to a verandah or terrace(s) which have access to the street, or roof of a building, or a refuge 
area. An exit may also include a horizontal exit leading to an adjoining building at the same level.  
3.2.2 Lifts and escalators should not be considered as exits.  
3.3 Occupant load 
3.3.1 For determining the exits requirement, the number of persons within any f loor area or the occupant 
load should be based on the actual number of occupants and shall not be  less than the value  specified in 
Table 1.  
3.3.2 The occupant load of a mezzanine floor and balcony discharging to a floor below should be added to 
that floor occupancy load thus established.  DRS 186 -5: 201 8 
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Table 1 — Occupant l oad  
S/N Group of Occupants  
(see RS 186-1) Occupants load, 
floor area in 
m2/person  
1 Residential  (A) 12.5 
2 Educational  (E) 4 
3 Institutional  (I) 
(See 3.3.3)  15 
4 Assembly  
(A) With fixed or loosese ats and 
dance floors  
(see 3.3.3)  0.6 
Without seating facilities  
including dining rooms  (see 
3.3.4)  1.5 
5 Mercantile:  
(M) street floor and sales 
basement  3 
upper sale floors  
6 Business and 
industrial  (F) 10 
7 Storage  (S) 30 
8 Hazardous  (H) 10 
3.3.3  Occupant load in dormitory portions of homes for the aged, orphanages, insane asylums etc., where 
sleeping accommodation is provided, should b e not less than 35 m2 as gross floor area/person.  
3.3.4  The gross floor area should include, in addition to the main assembly room or space, any occupied 
connecting room or space in the same storey or in the storey above or below where entrance is common to 
such rooms and spaces and they are available for use by the occupants of the assembly place.  
No deduction s should be made in the gross area for corridors, closets or other subdivisions; the area should 
include all space serving the particular assembly occupancy.  
3.4 Arrangement and capacity of e xits 
3.4.1  The unit of exit width, used to measure the capacity of an y exit, should be 50 cm. A clear, width of 25 
cm should be counted as an additional half unit. Clear widths less than 25 cm should not be counted for exit 
width.  
3.4.2  Occupants per unit exit width should be in accordance with Table 2.   
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Table 2 — Occupants  per unit exit w idth to be in compliance with building code  
S/N Group of  
occupancy  Number of occupants  
Stairways  Ramps  Doors  
1 Residential  (A) 25 50 75 
2 Educational  (B) 25 50 75 
3 Institutional  (C) 25 50 75 
4 Assembly  (D) 40 50 60 
5 Business  (E) 50 60 75 
6 Mercantile  (F) 50 30 75 
7 Industrial  (G) 50 60 75 
8 Storage  (H) 50 60 75 
9 Hazardous  (J) 25 30 40 
 
3.4.3  When horizontal exit is provided in buildings of mercantile storage, industrial, business and assembly 
occupancies, the capacity per sto rey per unit width of exit of stairways in Table 2 may be increased by 50 %; 
and in buildings of institutional occupancy, it  may be increased by 100 % . 
3.4.4  Exits should be located in such way the travel distance on floor not exceed the distance given in Table 
3. 
3.4.5  The travel distance to an exit from the dead end of a corridor should not exceed half the distance 
specified in  Table 3  and not exceed 6m for  educational, Assembly and institutional occupancies . . 
3.4.6  Whenever more than one exit is require d for any room, space of floor of a building, exits should be 
placed as remote from each other as possible and should be arranged to provide direct access in separate 
directions from any point in the area served.  
Table 3 — Maximum travel distance c onstruct ion 
 
S/N Group of occupancy  
(See RS 186 -1) Type 1 and 2  
(m) Type 3 and 4  
(m) 
1 Residential  
 22.5 22.5 
2 Educational  
 22.5 22.5 
3 Institutional  22.5 22.5 DRS 186 -5: 201 8 
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4 Assembly  
 30.0 30.0 
5 Business  
 30.0 30.0 
6 Mercantile  
 30.0 30.0 
7 Industrial  
 45.0 30.0 
8 Storage  
 30.0 30.0 
9 Hazardous  
 22.5 22.5 
3.5 Number of e xists  
3.5.1  General r equirement  
3.5.1.1  All buildings which are more than 15 m in height and all buildings used as educational, assembly, 
institutional, industrial, storage ,and hazardous occupancies and mi xed occupancies with any of the aforesaid 
occupancies, having area more than 500 m2 on each floor should have a minimum two stairca ses 
3.5.1.2  The staircases  should be of enclosed type; at least one of them should be on external walls of 
buildings and shou ld open directly towards to the exterior, interior, open space or to an open place of safety.  
Further, the provision or otherwise of alternative staircase should be subject to the requirements of travel 
distance being complied with.  
3.5.2  Rooming house of resid ential b uildings  
3.5.2.1  Every sleeping room above the street floor should have access to two separate means of exits  
and  at least one of which should consist of an enclosed interior stairway or an exterior stairway, or a fire 
escape or horizontal exit . 
Exits  should be arranged as to provide a safe path of travel to the outside of the building without traversing 
any corridor or space exposed to an unprotected vertical opening.  
3.5.2.2  Any sleeping room below the street floor should have direct access to t he outside of the building.  
3.5.3  One or two f amily private d welling s or residential b uilding  
3.5.3.1  For more than two rooms, every occupied room excluding areas used solely for storage, should 
have at least two means of exit .  
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  At least one of the exit  should be a door or a stairway providing a means of unobstructed travel to the outside 
of the building or street or grade level   and not more than one of which may be a window.  No room or space 
should be occupied which is accessible only with a ladder, folding s tairs or through a trap door.  
3.5.3.2  All locking devices which would impede or prohibit exit, such as chain type bolts, limited opening 
sliding type locks and burglar locks which are not disengaged easily by quick -releasing catches, should be 
prohibited.  
3.5.3.3  All closet door latches should be such that even children m ay open the doors from inside.  
3.5.3.4  All bathroom door locks or fasteners should be designed to permit the opening of the locked or 
closed door from the outside in an emergency without the use of a special key. Every below -street -level 
sleeping room should have direct access to the outside of the building.  
3.5.4  Dormitories  
Dormitories, except those mentioned in 3.5.6  should  have exits arranged in such way that from any sleeping 
room or open dormitory sleeping area, there should be access to two separate and distinct exits in different 
directions  without  common path of travel ., 
In case  the room or space is subject to occupancy by not more than 10 persons and has a door opening 
directly to th e outside of the building at street or grade level,  or to an outside stairway in which case one exit is 
accepted.  
3.5.5  Apartment House  
3.5.5.1  Every individual living unit should comply with the requirements for occupancy sub -division R-2 in 
respect of exit . 
3.5.5.2  Every living unit should have access to at least two separate exits  reached by travel in different 
direction . The  common path of travel should  be permitted for the first 6 m   and single exit shall be permitted 
under any of the conditions given in 3.5.5 .3. 
3.5.5.3  The access of any building of less than two stories with basement containing a heating plant, 
group storage, incinerator room or paint shop or other hazardous occupancy, shall be limited to the exterior of 
the building.  
3.5.5.4  At least h alf of required exits should discharge direct to the outside of the buildings; any other exit 
should be the same as required for the hotels  3.5.6 . 
3.5.6  Hotels  
3.5.6.1  The access to e very floor including basements occupied for hotel purposes should have at leas t 
two separate exits  in different direction  from every point in any open area, or any room door . 
. 
3.5.6.2  Any room or compartment  at street or grade level may use such outside door as a single exit 
provided no part of the room or area is more than 15 m fr om the furthest point . DRS 186 -5: 201 8 
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 3.5.6.3  Where stairways or other exits serve two or more upper floors, the same stairway or other exit 
required to serve any one upper floor may also serve other upper floors except that no inside open stair -way 
or ramp may serve as a required egress facility from more than one floor.   
NOTE  under this provision, if the second and third floors were each required to have three stairways, the second 
floor may use the stairways serving the third floor so that the total number of stairways  required is three, and not six.  
3.5.7  Basement e xits f or residential b uildings  
3.5.7.1  Basement exits should be sufficient to provide for the occupancy of the basement as determined 
in accordance with 3.1.2 and should not be less than two independent basement exits.  
3.5.7.2  Basements or sub -basements not open to the public and used only for heating equipment, 
storage and service operations (other than kitchens which are considered part of the hotel occupancy) should 
have exits appropriate to the actual occupanc y. 
3.5.7.3  For mixed occupancy where there may be doubt as to which other section is applicable, such 
basements should have exits determined on the basis of lesser exit capacity.   
3.5.8  Education  
3.5.8.1  At least two separate exits should be available in every floor area  and should be isolated from 
each other as practicable and arranged in such way that there are no pockets or dead ends of appreciable 
size in which occupants may be trapped .  
3.5.8. 2 Every room with a capacity of over 100 persons should have at l east two door -ways isolated  from 
each other. Such doorways should provide access to separate exists but may open upon a common corridor 
leading to separate exits in opposite directions.  
3.5.8. 3 Exterior doors should be operated by bars or  an  equivalent  panic hardware device except that 
doors leading from classroom directly to the outside may be equipped with the same type of lock as is used on 
classroom doors leading to corridor with no provision for locking against egress from the classroom.  
3.5.9  Institutional   
3.5.9.1  Not less than two exits of one or more of the following types should be provided for every floor, 
including basement, of every building or compartment : 
a) doors leadin g directly outside the building;  
b) stairways;  
c) ramps;  and 
d) horizontal exits.   
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 3.5.9.2  All required exits which serve as egress from hospital or infirmary sections should be not less 
than 150 cm in clean width, including patient bedroom doors, to permit transport of patients on beds, litters or 
mattresses. The minimum widths of corridors serv ing patients bedrooms in building should be 240 cm.  
3.5.9.3  Revolving doors should not be counted as required exists and should not be installed, except in 
situations, such as revolving doors at a main entrance where they are not subject to emergency exit use by 
patients.  
3.5.9.4  Elevators constitute a desirable supplementary facility but are not counted as required exits.  
3.5.9.5  Each storey accommodate  35 or more patients should be divided into at least two compartments 
by smoke barriers and the Authorit y may require storeys housing a lesser number of patients to be divided 
into compartments when, in its judgment, such division its essential for the protection of the patients.  
3.5.9.6  Doors in smoke barriers should be installed such that these may normall y be kept in open 
position but will close automatically or my be released manually to self -closing action.  
Corridor door openings in smoke barriers should not be less than 150 cm in width. Provision should also be 
made for double swing single/double leaf type door.  
3.5.9.7  Exits and other features for penal and mental institutions, and custodial institutions should be the 
same as specified for hospitals. Reliable means should be provided to permit the prompt release of inmate 
from any locked section in cas e of fire or other emergency.  
3.5.9.8  Wherever any inmates are confined in any locked rooms or spaces, adequate guards or other 
personnel should be continuously on duty or immediately available to provide for release of inmates or for 
such other action as may be indicated in case of fire or other emergency.  
3.5.9.9  No building constructed in whole or in part of combustible materials should be used to combine 
inmates in cells or sleeping quarters unless automatic sprinkler protection is provided.  
3.5.9.10  All buildings or sections of build ings penal and mental institutions used for manufacturing, storage 
or office purposes should have exits in accordance with the provisions of occupancies .  
3.5.10  Assembly b uildings  
3.5.10.1  Every place of assembly, every tier or b alcony, and every individual room used as a place of 
assembly should have exits sufficient to provide for the total capacity . 
3.5.10.2  Every place of assembly of subdivision A-1 should have at least four separate exits isolated  from 
each other.  
3.5.10.3  Every place of assembly of sub -division A-2 should have at least two separate exits isolated  from 
each other, and if capacity over 600, three exits should be provided with each exit not less than of 2 unit 
widths.  
3.5.10.4  Every place of assembly of sub -divisions A-3, A-4 and A-5 should have at least two means of exit  
consisting of separate exits or doors leading to corridor or other spaces giving access to two separate and 
independent exits in different directions . DRS 186 -5: 201 8 
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 For places of assembly hav ing a capacity o f less than 100  persons, one 2 -unit doorway may be permitted in 
rooms where no part of the room is more than 15 m from the doorway, measured along the line of travel, and 
the doorway leads directly outside the building at grade level or leads to a corridor  or other space giving 
access to two separate and independent exits.   
3.5.10.5  Clear aisles no t less than 1 .2 m in width should be formed at right angles to the line of seating in 
such number and manner that no seat should be more than seven seats away fro m an aisle. Rows of seats 
opening on to an aisle at one end only should have not more than seven seats.  
3.5.10.6  Under the conditions when all these aisles do not directly meet the exit doors, cross -aisles should 
be provided parallel to the line of seatin g so as to provide direct access to the exit, provided that not more 
than one cross -aisle for every 10 rows should be required.  
3.5.10.7  The width of cross isles should be a minimum of 1 m. Steps should not be placed in aisles to 
overcome differences in l evels unless the gradient exceeds 1 in 10.  
3.5.10.8  The fascia of boxes, balconies and galleries should have substantial railings not less than 65 cm 
high above the floor. The railings at the end aisles extending to the facial should be not less than 75 cm  high 
for the width of the aisle , or 90 cm high at the foot of steps.  
3.5.10.9  Cross -aisles except where the backs of seats on the front of the aisle project 60 cm or more 
above the floor of the aisle, should be provided with railings not less than 90 cm h igh. 
3.5.10.10  No turnstiles or other devices to restrict the movement of persons should be installed in any place 
of assembly in such a manner as to interfere in any way with the required exit facilities.  
3.5.10.11  In theatres and similar places of public  assembly where persons are admitted to the building at a 
time when seats are not available for them and are allowed to wait in a lobby or similar space until seats are 
available, such use of lobby or similar space should not encroach upon the required cle ar width of exits.  
3.5.10.12  Such waiting should be restricted to areas separated from the required exit ways by substantial 
permanent partitions or fixed rigid railing not less than 105 cm high. Exits should be provided for such waiting 
spaces on the basi s of one person for each 0.3 m2 of waiting space; such exits should be in addition to the 
exits specified for the main auditorium area and should conform in construction  and arrangement to the 
general rules of exists given above.  
3.5.10.13  No display or ex hibit should be so installed or operated as to interfere in any way with access to 
any required exit, or with any required exit sign. Al displays or exhibits of combustible material or construction 
and all booths and temporary construction in connection wi th it should be so limited in combustibility or 
protected as to avoid any undue hazard of fire which might endanger occupants before they have opportunity 
to use the available exits.  
3.5.10.14  No mirrors should be placed in or adjacent to any exit way in s uch a manner as to confuse the 
direction of the exit.  
3.5.10.15  Places of assembly in buildings of other occupancy may use exits common to the place of 
assembly and other occupancy. Provided the assembly area and other occupancy are considered separately, 
each has exits sufficient to meet the requirements.   
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 3.5.10.16  Exits should be sufficient for simultaneous occupancy of both the places of assembly and other 
parts of the building, unless the conditions are such that simultaneous occupancy will not occur.  
3.5.10.17  For any place of assembly under subdivision D -1, at least half the required means of exits should 
lead directly outdoors or through exit ways completely separated from exits serving other parts of the building.  
3.5.11  Business  
3.5.11.1  In the case of me zzanines or balconies open to the floor below, or other unprotected vertical 
openings between floors, the population of the mezzanine or other subsidiary floor level should be added to 
that of the main floor for the purpose of determining the required exit s, provided, however, that in no case 
should the total number of exits, units be less than that required if all the vertical openings were enclosed.  
3.5.11.2  Not less than two exits should be provided for every floor, including basements occupied for offic e 
purposes or uses incidental thereto.  
3.5.12  Mercantile  
3.5.12.1  In the case of mezzanines or balconies open to the floor below, or other unprotected vertical 
openings between floors, the population or area of the mezzanine or other subsidiary floor level shoul d be 
added to that of the main floor for the purpose of determining the required exits, provided, however, that in no 
case should the total number of exits units be less than that required if all vertical openings were enclosed.  
3.5.12.2  At least two separ ate exits should be accessible from every part of every floor, including 
basements; such exits should be as remote from each other as practicable and so arranged as to be reached 
by different paths of travel in different directions except that a common pat h of travel may be permitted for the 
first 15 m from any point.  
3.5.13  Industrial  
3.5.13.1  In buildings used for aircraft assembly or other occupancy requiring undivided floor areas so large 
that the distance from points within the area to the nearest outside wa lls where exit doors could be provided 
are in excess of 45 m, requirements for distance to exits may be satisfied by providing stairs leading to exit 
tunnels or to overhead passageways.  
3.5.13.2  In cases where such arrangements are not practicable, permit other exits arrangements for one 
storey buildings with distance in excess of the maximum distances specified in 3.4. 
3.5.13.3  If completely automatic sprinkler protection is provided and if the heights of ceiling curtain boards 
and roof ventilation are suc h as to minimize the possibility that employees will be overtaken by the spread of 
fire or smoke within 180 cm of the floor level before they have time to reach exits, provided, however, that in 
no case may the distance of travel to reach he nearest exit e xceed 120 m where smoke venting is required as 
a condition for permitting distances of travel to exits in excess of the maximum otherwise allowed.  
3.5.13.4  Basements used only for storage, heating and other service equipment, and not subject to 
industrial occupancy should have exits in accordance with the requirements of Group H occupancies.  
3.5.13.5  The following exceptions should apply to special purpose industrial occupancies:  DRS 186 -5: 201 8 
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 a) exits need be provided only for the persons actually employed; spaces not subj ect to human occupancy 
because of the presence of machinery or equipment may  be excluded from consideration; and  
b) where unprotected vertical openings are necessary to manufacturing operations, these may be permitted 
beyond the limits specified for industria l occupancy provided every floor level has direct access to one or 
more enclosed stairways or other exits protected against obstruction by any fire in the open areas 
connected by the unprotected vertical openings or smoke there from.  
3.5.13.6  Exceptions fo r high hazard industrial occupancies are provided for in 3.5.15.  
3.5.14  Storage  
3.5.14.1  Every building or structure used for storage, and every section thereof considered separately, 
should have access to at least one exit so arranged and located as to provide a  suitable means of escape for 
any person employed therein and in any room or space exceeding 1 400 m2 gross area, or where more than 
10 persons may be normally present, at least two separate means of exit shall be available, as remote from 
each other as pr acticable.  
3.5.14.2  Every storage area should have access to at least one means of exit which can be readily 
opened. This should not be subject to locking so long as any persons are inside and should not depend on 
power operation.  
3.5.14.3  The following sp ecial provisions should apply to parking garages of closed or open type, above or 
below ground but not to mechanical parking facilities where automobiles move into and out of storage 
mechanically which are not normally occupied by persons and thus require  no exit facilities.  
3.5.14.4  Where repair operations are conducted, the exits should comply with the requirements of Group 
G occupancies in addition to compliance with the following:  
a) where both parking and repair operations are conducted in the same build ing, the entire building should 
comply with the requirements for Group G occupancies unless the parking and repair sections are 
effectivel y separated by separation walls;  
b) every floor of every closed parking garage should have access to at least two separat e means of exit so 
arranged hat from any point in the garage, the paths of travel to the two means of exit should be in 
different directions, except that a common path of travel may be permitted for  the first 15  m from any 
point;  
c) on the street floor, at le ast two separate exit doors should be provided except that any opening from the 
passage of automobiles may serve as a means of exit provided no door or shutter is installed thereon. 
Street floor exits in closed garages should be so arranged that no point i n the area is more than 30 m 
from the nearest exit, or 45 m in the case of garages protected by automatic sprinklers, distance being 
measured a long the natural path of travel;  
d) on floors above the street, at least two means of exit should be provided, one o f which should be an 
enclosed stairway. The other means of egress may be a second exit of any of the types , or in a ramp 
types, or in  a ramp type garage with open ramps not subject to closure, the ramp may se rve as the 
second means of exit;   
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 e) upper floor exi ts in closed garages should be so arranged that no point in the area should be more than 
30 m from the nearest exit other than a ramp on the same floor level, or 45 m in the case of garages 
protected by automatic sprinklers;  
f) on floors below the street (eit her basement or outside underground garages), at least two exits should be 
provided, not counting any automobile ramps except that for garages extending only one floor level below 
the street, a ramp leading direct to the outside may constitute one required  means of exit. In garages 
below street level, exits should be so arranged that no part of the area should be more than 3 0 m from 
the nearest stair exit; and  
g) if any gasoline pumps are located within any closed parking garage, exits should be so located tha t travel 
away from the gasoline pump in any direction should lead to an exit, with no dead -end in which the 
occupants might be trapped by fire or explosion at any gasoline pump. Such exit should lead to the 
outside of the building on the same level, or dow nstairs; no upward travel should be permitted unless 
direct outside exits are available from the floor and any floor below (as in the case of a basement garage 
where the grade is one storey or more lower at the real than at the street).  
3.5.14.5  Exits from  aircraft hangars (storage or servicing areas) should be provided at intervals of not 
more than 45 m on all exterior walls of aircrafts hangars.   
3.5.14.6  There should be a minimum of two exits serving each aircraft storage or servicing area. 
Horizontal e xits through interior fire walls should be provided at intervals of not more than 30 m.  
3.5.14.7  “Dwarf” or “smash” doors in doors accommodating aircraft may be used to comply with these 
requirements. All doors designated as exits should be kept unlocked i n the direction of exit travel while the 
area is occupied.  
3.5.14.8  Exits from mezzanine floors in air -craft storage or servicing area should be so arranged that the 
maximum travel to reach the nearest exit from any point on the mezzanine should not exceed  22.5 m. Such 
exits should lead directly to a properly enclosed stairwell discharging directly to the exterior or to a suitably 
cut-off area or to outside fire escape stairs.  
3.5.14.9  The following provisions should apply to grain elevators:  
a) there should a t least be one stair tower from basement to first floor and from first floor to top floor of the 
workhouse enclosed in a dust -tight non -combustible shaft;  
b) non-combustible doors of self -closing type should be provided at, each floor landing;  
c) an exterior fir e escape of the stair or basket ladder type should be provided from the roof of the 
workhouse to the ground level or to the roof of an adjoining annexe with access from all floors above the 
first; and.  
d) an exterior fire escape or either the stair or basket ladder type should be provided from the roof of each 
storage annexe to the ground level.  
3.5.14.10  Every area used for storage of hazardous commodities should have an exit within 22.5 m of any 
point in the area where persons may be present or 30 m where au tomatic sprinkler protection is provided.  DRS 186 -5: 201 8 
13                 ©RSB 2018 All rights reserved  
 
 3.5.15  Hazardous and high hazards i ndustrial occupancies  
3.5.15.1  Exits should be so located that it will not be n ecessary to travel more than 22. 5 m from any point 
to reach the nearest exit.  
3.5.15.2  From every point in every floor area, there should at least be two exits accessible in different 
directions; where floor areas are divided into rooms, there should be at least two ways of escape from every 
room, however small, except toilet rooms, so located that the points o f access thereto are out of or suitably 
shielded from areas of high hazard.  
3.5.15.3  In addition to types of exits for upper floors specified for Group G occupancies, slide escapes may 
be used as required exits for both new and existing buildings.  
3.6 Doorways  
3.6.1  Every exit doorway should open into an enclosed stairway, or horizontal exit of a corridor, or 
passageway providing continuous and protected means of egress.  
3.6.2  No exit doorway should be less than 100 cm in width. Doorways should be not less than  20 cm in 
height.  
3.6.3  Exit doorways should open outwards, that  is, away from the room but should not obstru ct the travel 
along any exit. N o door, when opened, should reduce the required width of stairway or landing to less than 90 
cm; over -head or slidin g door should not be installed.  
NOTE  In the case of buildings where there is a central corridor, the doors of rooms should open inwards to permit 
smooth flow of traffic in the corridor.  
3.6.4  Exit door should not open immediately upon a flight of stairs, a  landing equal to at least the width of 
the door should be provided in the stairway at each doorway; the level of landing should be the same as that 
of the floor which it serves.  
3.6.5  Exit doorways should be openable from the side which they serve without  the use of a key.  
3.6.6  Revolving doors should not be used as required exits except in residential, business and mercantile 
occupancies but should not constitute more than half the total required door width. In mercantile buildings 
where there is possibil ity of congregation of a large number of people (more than 200), revolving doors should 
not be permitted.  
3.6.7  Where the revolving door  provided is completely made of glass (plate glass), a red circle or emblem 
or logo at 1.5 m level above sill should be painted on the glass.  The thickness  of the glass should not be less 
than 12 mm.  
3.7 Corridors  and p assageways  
3.7.1  Exit corridors and passageways should be of width not less than the aggregate required width of exit 
doorways leading from them in the direction  of travel to the exterior.   
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 3.7.2  Where stairways discharge through corridors and passageways, the height of corridors and 
passageways should be not less than 2.4 m.  
3.8 Internal s taircases  
3.8.1  Interior stairs should be constructed of non -combustible materia ls throughout.  
3.8.2  Interior staircase should be constructed as a self -contained unit with an external wall constituting at 
least one of its sides and should be completely enclosed.  
3.8.3  A staircase should not be arranged round a lift shaft unless the la tter is totally enclosed by a material 
of fire -resistance rating as that for the type of construction itself.  
3.8.4  Hollow combustible construction should not be permitted.  
3.8.5  Hollow combustible construction should not be permitted.  
3.8.6  No gas piping should be laid in the stairway.  
3.8.7  Notwithstanding the detailed provision for exits given above the following minimum width should be 
provide for staircases:  
a) residential buildings (dwellings) 1.0 m ; 
NOTE  For row housing with 2 storeys, the width should be 0,75 m  
b) residential hotel buildings ; 
c) assembly buildings like auditorium, theatres and cinemas ; 
d) educational buildings:  
i) up to 24 m in height ; and  
ii) more than 24 m in height . 
e) institutional buildings like hospitals:  
i) up to 10 beds ; and  
ii) more than 10 beds . 
f) all other buildings . DRS 186 -5: 201 8 
15                 ©RSB 2018 All rights reserved  
 
 3.8.8  The minimum width of tread without closing should be 25 cm for internal staircase of residential 
buildings. This should be 30 cm for assembly, education, institutional, business and other buildings. The 
treads should be constructed and  maintained in a manner to prevent slipping.  
3.8.9  The maximum height of riser should be 19 cm for residential buildings and 15 cm for other buildings 
and the number should be limited to 15 per flight.  
3.8.10  Hand rails should be provide at a minimum hei ght of 100 cm and not exceeding 120 cm to be 
measured from the base of the middle of the treads to the top of the hand rails. Further, the gap between the 
two verticals should not exceed 30 cm. This gap should be reduced to 15 cm where children are likely t o use 
the staircase.  
3.8.11  The number of people in between floor landings in staircase should not be less than the population on 
each floor for the purpose of design of staircase.  
3.9 Fire escapes or external s tairs  
3.9.1  Fire escapes should not be taken into  account in calculating the evaluation time of a building.  
3.9.2  All fire escapes should be directly connected to the ground.  
3.9.3  Entrance to the fire escape should be separate and remote from the internal staircase.  
3.9.4  Care should be taken to ensure that the wall opening or window opens on to or close to a fire escape.  
3.9.5  The route to the fire escape should be free of obstructions at all times.  
3.9.6  The fire escape should be constructed of non -combustible materials, and any doorway leading to the 
fire escape should have the required fire resistance.  
3.9.7  No staircase, used as a fire escape should be inclined at an angle greater than 45° to the horizontal.  
3.9.8  Fire escape stairs should have straight fight not less than 75 cm wide with 20 cm tread s and risers not 
more than 19 cm. The number of risers should be limited to 15 per flight.  
3.9.9  Hand rails should be of a height not less than 100 cm and not exceeding 120 cm.  
3.10 Spiral fire e scape  
3.10.1  The use of spiral staircase should be limited to occu pant load and to a building not exceeding 9 m in 
height unless they are connected to platforms, such as balconies and terraces to allow escapees to pause.  
3.10.2  Spiral fire escape should be not less than 150 cm in diameter and should be designed to give 
adequate headroom.   
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 3.11 Roof e xit  
3.11.1  In all buildings over three storeys in height where the slope of the roof is less than 20 degrees, direct 
access to the roofs is less than 20 degrees; direct access to the roofs should be provided from the street by 
mean s of stairway.  
3.11.2  Where roofs are used as roof gardens or for other habitable purposes, sufficient stair -ways should be 
extended to them to provide necessary exit facilities required for such occupancy.  
NOTE  This does not apply to A -2 and A -4 occupanci es up to 15 m height.  
3.11.1  Horizontal e xits 
3.11.1.1  The width of horizontal exit should be the same as for the exit doorways  see 3.6   
3.11.1.2  A horizontal exit should be equipped with at least one fire door of self -closing type.  
3.11.1.3  Floor area on the opp osite or refuge side of a horizontal exit should be sufficient to accommodate 
occupants of the floor areas served, allowing not less than 0.3 m2 per person.   
3.11.1.4  The refuge area into which a horizontal exit leads should be provided with exits adequat e to meet 
the requirements given in this standard. At least one of the exits should lead directly to the exterior of building 
or to a street.  
3.11.1.5  Where there is a difference in level between connected areas for horizontal exits, ramps, not 
more than 1  in 10 in slope should be provided; steps should not be used.  
3.11.1.6  Doors in horizontal exits should be openable at all times from both sides.  
3.12 Fire t ower  
3.12.1  Fire towers are the preferred type of escape route for storeyed buildings and their applicat ion should 
be considered as the safes route for escape. Their number, location and size should depend on the building 
concerned and its associated escape routes.  
3.12.2  In every mercantile, industrial, business, assembly buildings other than theatres, inst itutional and 
residential buildings, over 6 storeys or 25 m in height, at least one required means of egress should be a fire 
tower.  
3.12.3  The enclosure of fire towers should be constructed of walls with a 4 h fire -resistance rating without 
openings other  than the exit door -ways with platform, landings and balconies of not less than 3 h fire -
resistance rating.  
3.13 Ramps  
3.13.1  Ramps should comply with all the applicable requirements for stairways regarding enclosure, capacity 
and limiting dimensions except whe re specified for special uses and occupancies.  DRS 186 -5: 201 8 
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 3.13.2  The slope of a ramp should not exceed 1 in 10. In certain cases, steeper slopes may be permitted but 
in no case greater than 1 in 8.  
3.13.3  For all slopes exceeding 1 in 10 and wherever the use is such as to involve danger of slipping, the 
ramp should be surfaced with approved non -slipping material .  
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 RS 186 -5: 2013  
ICS 13.220.40  
 
 
©RBS 2013 All rights reserved