DRAFT UGANDA STANDARD  
  DUS  1756 -2:2017  
First E dition  
2017 -mm-dd 
 
 
 Reference number  
DUS 1756 -2: 2017  
© UNBS 2017   
  
Commer cial blasting explosives  — Specification — Part 2: 
Ammoniu m Nitrate  Fuel Oil explosives  
 DUS 1756 -2: 2017  
ii © UNBS 2017  – All rights reserved  
 Compliance with this standard does not, of itself confer immunity from legal obligations  
A Uganda Standard does not purport to include all necessary provisions  of a contract. Users are 
responsible for its correct application  
© UNBS 2017   
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilised in any 
form or by any means, electronic or mechanical, including photo copying and microfilm, without prior written 
permission from UNBS.  
Requests for permission to reproduce this document should be addressed to  
The Executive Director  
Uganda National Bureau of Standards  
P.O. Box 6329  
Kampala  
Uganda  
Tel: +256 41 4 333 2 50/1/2/3  
Fax: +256 41 4 286 123  
E-mail: info@unbs.go.ug  
Web: www.unbs.go.ug  DUS 1756 -2:2017  
© UNBS 2017  – All rights reserved  iii 
 Contents  Page 
Foreword  ................................ ................................ ................................ ................................ .............................  v 
Introduction  ................................ ................................ ................................ ................................ ........................  vi 
1 Scope  ................................ ................................ ................................ ................................ ......................  1 
2 Normative references  ................................ ................................ ................................ ............................  1 
3 Terms and definitions  ................................ ................................ ................................ ...........................  1 
4. Requirements  ................................ ................................ ................................ ................................ .........  1 
4.1.1  General requirements  ................................ ................................ ................................ ...........................  1 
4.1.2  Density  ................................ ................................ ................................ ................................ ....................  2 
4.1.3  Shelf life  ................................ ................................ ................................ ................................ ..................  2 
4.1.4  Sleep Time  ................................ ................................ ................................ ................................ ..............  2 
4.2 Blast performance requirements  ................................ ................................ ................................ .........  2 
5 Inspection and sampling  ................................ ................................ ................................ ......................  2 
5.1 General  ................................ ................................ ................................ ................................ ...................  2 
5.2 Inspection  ................................ ................................ ................................ ................................ ...............  3 
5.3 Sampling  ................................ ................................ ................................ ................................ ................  3 
6 Packaging and labelling ................................ ................................ ................................ ........................  3 
6.1 Packaging  ................................ ................................ ................................ ................................ ...............  3 
6.2 Labeling  ................................ ................................ ................................ ................................ ..................  3 
Annex A (normative)  Oxygen balance test  ................................ ................................ ................................ ..... 5 
A.1 Description  ................................ ................................ ................................ ................................ .............  5 
A.2 Procedure  ................................ ................................ ................................ ................................ ...............  5 
A.3 Calculations  ................................ ................................ ................................ ................................ ...........  5 
Annex B (normative)  Capacity to work test  ................................ ................................ ................................ .... 6 
B.1 Trauzl lead block test  ................................ ................................ ................................ ............................  6 
B.2 Procedur e ................................ ................................ ................................ ................................ ...............  6 
Annex C (normative)  Detonation velocity  ................................ ................................ ................................ ....... 7 
C.1 Dautriche Method  ................................ ................................ ................................ ................................ .. 7 
C.2 procedure  ................................ ................................ ................................ ................................ ...............  7 
C.3 Calculation  ................................ ................................ ................................ ................................ .............  8 
Annex D (normative)  Explosive energy  ................................ ................................ ................................ ...........  9 
D.1 Under water test method/ bubble test  ................................ ................................ ................................ . 9 
D.1.1  Procedure  ................................ ................................ ................................ ................................ ...............  9 
D.1.2  Calculation  ................................ ................................ ................................ ................................ .............  9 
D.2 Ballistic mortar test  ................................ ................................ ................................ .............................  10 
D.2.1  Method of test  ................................ ................................ ................................ ................................ ...... 10 
D.2.2  Calculation  ................................ ................................ ................................ ................................ ...........  10 
Annex E (normative)  weight strength  ................................ ................................ ................................ ............  12 
E.1 Absolute weight strength (AWS)  ................................ ................................ ................................ ....... 12 
E.2 Relative weight strength (RWS)  ................................ ................................ ................................ .........  12 
Annex F (normative)  Bulk Strength  ................................ ................................ ................................ ...............  13 
F.1 Absolute Bulk Strength (ABS)  ................................ ................................ ................................ ...........  13 
F.2 Relative Bulk Strength (RBS)  ................................ ................................ ................................ .............  13 
Annex G (normative)  Sampling and compliance with this standard  ................................ .........................  14 
G.1 Sampling  ................................ ................................ ................................ ................................ ..............  14 
G.1.1  Preservation  ................................ ................................ ................................ ................................ .........  14 DUS 1756 -2: 2017  
iv © UNBS 2017  – All rights reserved  
 G.1.2  Lot ................................ ................................ ................................ ................................ ........................  14 
G.2 Compliance with this standard  ................................ ................................ ................................ ..........  14 
Bibliography  ................................ ................................ ................................ ................................ .....................  15 
 DUS 1756 -2:2017  
© UNBS 2017  – All rights reserved  v 
 Foreword  
Uganda National Bureau of Standards (UNBS) is a parastatal under the Ministry of Trade , Indust ry and 
Cooperatives established under Cap 327 , of the Laws of Uganda , as amended .  UNBS is mandated to co -
ordinate the elaboration of standards and is  
(a) a member of International Organisation for Standardisation (ISO) and  
(b) a contact point for the WHO/FAO Co dex Alimentarius Commission on Food Standards, and  
(c) the National Enquiry Point on TBT  Agreement  of the World Trade Organisation (WTO).  
The work of preparing Uganda Standards is carried out through Technical Committees. A Technical 
Committee is established to deliberate on standards in a given field or area and consists of key stakeholders 
including government, academia, consumer groups, private sector and other interested parties.  
Draft Uganda Standards adopted by the Technical Committee are widely circula ted to stakeholders and the 
general public for comments. The committee reviews the comments before recommending the draft standards 
for approval and declaration as Uganda Standards by the National Standards Council.  
The committee responsible for this docum ent is Technical Committee UNBS /TC 5, Chemicals and 
environment ] 
US 1780  consists of the following parts, under the general title Commercial blasting explosives — 
Specification :  
  Part 1 : Emulsion explosives  
  Part 2 : Ammonium Nitrate - Fuel Oil explosive s 
  Part 3 : Ammonium Nitrate for explosives  
 — Part 4: Sodium Nitrate for explosives  DUS 1756 -2: 2017  
vi © UNBS 2017  – All rights reserved  
 Introduction  
An explosive is a compound or a mixture of compounds, which when initiated by heat, impact, friction or shock 
undergoes a very rapid self -propagating exotherm ic reaction. This reaction produces more stable products, 
usually gases that exert tremendous pressure as they expand at high temperature.  
Explosives can be classified into two broad groups, namely, the industrial explosive and the military 
explosives. Ind ustrial explosives are also known as commercial explosives and include dynamites, slurries, 
emulsions and blasting powders. Military explosives are mainly used as ammunition in small arms as well as 
field guns and rockets. • Slurries consist of saturated a queous solution of ammonium nitrate and other nitrates 
which also contain additional amounts of undissolved nitrates in suspension. Fuels are added to the 
composition in order to take up the excess oxygen of nitrates. Sensitizer in slurries can be monometh ylamine 
nitrate, dispersed air bubbles, aluminium powder, etc.  
 DRAFT UGANDA STANDARD  DUS 1756 -2: 2017  
 
© UNBS 2017 – All rights reserved  1 
 Commercial blasting explosives — Specification — Part 2: 
Ammonium Nitrate  Fuel Oil explosives  
1 Scope  
This Draft Uganda S tandard specifies requirements, methods of test and sampling of Ammoni um Nitrate Fuel Oil 
explosives  
NOTE  1 The requirements of this standard should be read in conjunction with the Act of 1964 cap 309 and /or other 
applicable regulations  
NOTE  2 This standard does not purport to address all of the safety concerns, if any, asso ciated with its use. It is the 
responsibility of the user of this standard to establish appropriate safety and health practices and determine the 
applicability of regulatory limitations prior to use  
2 Normative references  
The following referenced documents  referred to in the text in such a way that some or all of their content 
constitutes requirements of this document. For dated references, only the edition cited applies. For undated 
references, the latest edition of the referenced document (including any a mendments) applies.  
DUS 1776:2017; light metal in hazardous location at mines — Guidelines for use  
DUS 1757: 2017; Commercial blasting explosives  — Terminology  
US ISO 7010: 2011; Graphical symbols — Safety colours and safety signs — Registered safety signs  
3 Terms and definitions  
For the purposes of this document, the terms and definitions given in DUS 1757  and the following apply.  
3.1 
fuel oil  
any liquid fuel that is burned in a furnace or boiler for the generation of heat or used in an engine for the 
generation of power  
4. Requirement s 
4.1.1 General  requirement s 
The permitted  explosive shall be of a granular material, which is loose and free -flowing containing 94% (by 
weight) ammonium nitrate and 6% (by weight) fuel oil and shall be capable of initiation by a permitted 
detonator .  
2 © UNBS 2017  – All rights reserved  
 4.1.2  Density  
The density of the explosive shall be within ± 0.05 g/cm3 of that claimed by the manufacturer and fall wi thin a 
range of 0.65-0.9 g/cm3 
4.1.3  Shelf life  
An explosive shall have maximum shelf life of two (2) months fr om time of manufacture dependent on 
temper ature and humidity conditions d uring storage under conditions specified in the relevant national 
legislation and approved by the competent authority  
4.1.4  Sleep Time  
The explosive shall have a sleep time of up to six (6) weeks  from the time of manufacture  under normal 
conditions in dry and stemmed blast holes.  
NOTE  The sleep time may be limited to the recommended sleep time of the initiating system.  
4.2 Blast performance requirements  
All permitted ANFO  explosives m anufactured for commercial use,  in addition to meeting the  general  
requirements stipulated is clause 4.1  abov e, shall comply with blast performance requirements  as specified in  
the table 1 below.  
Table 1 —Blast performance requirements  
Test Units  Expected Result  Test Method  
Oxygen balance  %(m/m)  + 0.5 Annex A  
Capacity for Work  ml ≥ 260 Annex B  
Detonation Velocity1  ms-1 2500 – 4800  Annex C  
Energy  MJ/kg  3.7 Annex D  
Relative Weight Strength  
(RWS)  % 100 Annex E  
Relative Bulk 
Strength(RBS)  % 100 - 115 Annex F  
1 The actual VOD depends on the conditions of use including the diameter  of the hole and the degree of 
confinement  
 
5 Inspection and sampling  
5.1 General  
Owing to the dangerous nature of explosives, extreme care and caution shall be exercised during the 
inspection, sampling and testing of explosives. All safety precautions an d procedures laid down in th e relevant 
national legislation s and those in DUS 1776:  2017  shall be strictly followed.  
The sampling procedure given in annex G shall be applied in determining whether a lot complies with the 
appropriate requirements of this st andard.  DUS 1756 -2: 2017  
© UNBS 2017 – All rights reserved  3 
 5.2 Inspection  
Inspect the explosives for compliance wi th the requirements of clause 4  
5.3 Sampling  
In a single consignment of the material all the containers of the same, type and size and drawn from the same 
batch of manufacture shall constitute a lot. If a consignment is known to consist of different batches of 
manufacture or of different types and sizes of containers, the containers belonging to the same batch type and 
size shall be grouped together and each such group shall constitute a separat e lot.  
The number of containers to be selected at random from lots of different sizes shall be in accordance with 
Table 2. 
Table 2 — Sample sizes to be considered  
Lot size  Sample size  
Up to 15  3 
16 to 25  4 
26 to50  5 
51 to100  7 
101 and above  10 
 
6 Packaging and  labelling  
6.1 Packaging  
Explosives  shall be packed in water tight polyethylene lined  bags  of not less than 0.05 mm thick or in such 
other containers . The  polyethylene bags shall be such that no leakage of the explosive occurs under normal 
condit ions of trans portation, handling and storage. Explosive plastic bags shall be packed in accordance with 
the relevant national legislation  
6.2 Labeling  
6.2.1  Each package shall also be marked with appropr iate explosive symbol as specified in  US IS0 7010 . 
6.2.2 Each package shall be legibly and indelibly marked with the following information:  
a) indication of the s ource of manu facture;  
b) name of the explo sives;  
c) batch / lot number ; 
d) expiry and manufacture date;  
e) country of origin;  
f) gross and net weight; and  
g) manufactu re or trade mark.   
4 © UNBS 2017  – All rights reserved  
 In addition to the above, the following cautionary note shall also appear on the label in red ink:  “HIGHLY 
EXPLOSIVE. HANDLE WITH UTMOST CARE. DO NOT DROP OR SUBJECT TO HEAT. FRICTION OR 
SHOCK. DO NOT BRING ANY SPARK OR FLAME NEAR THE PAC KAGE. DO NOT STORE  OR STOCK  
AND TRANSORT  WITH THE DETONATORS ” DUS 1756 -2: 2017  
© UNBS 2017 – All rights reserved  5 
 Annex  A 
(normative)  
 
Oxygen balance test  
A.1 Description  
The oxygen balance is an expression that is used to indicate the degree to which an explosive can be 
oxidized.  
If an explosive molecule contains just enough oxygen to convert all of its carbon to carbon dioxide, all of its 
hydrogen to water, and all of its metal to metal oxide with no excess, the molecule is said to have a zero 
oxygen balance. The molecule is said to have a positive oxygen  balance if it contains more oxygen than is 
needed and a negative oxygen balance if it contains less oxygen than is needed.  
A.2 Procedure  
A.2.1  Obtain 100 grams of the explosive material  
A.2.2  Determine the number of gram atoms of oxygen that are excess o r deficient for 100 grams of a 
compound  
A.2.3  Calculate the empirical formula of a compound in percentage of oxygen required for complete 
conversion of carbon to carbon dioxide, hydrogen to water, and metal to metal oxide.  
A.3 Calculations  
Mzyx
OB


22 1600
 1 
where 
M is the number of atoms of metal (metallic oxide produced) ; 
x is the number of carbon atoms ; 
y is the number of hydrogen atoms ; 
z is the number of oxygen atoms .  
6 © UNBS 2017  – All rights reserved  
 Annex  B 
(normative)  
 
Capacity to work test  
B.1 Trauzl lead block test  
Is a test used to measure the strength of explosive materials and the capacity to work  
B.2 Procedure  
B.2.1  A cylindrical block of lead, 20 centimetres  high and 20 centimetres  in diameter is used.  
B.2.2  A hole is drilled in the centre  of the  flat face that is 2.5 centimetres  in diameter and 12.5 centimetres  
deep.  
B.2.3  Into the hole, place 10 grams of the test explosive, and a standard number 8 blasting cap.  
B.2.3  Fill the hole with fine sand (tamped), and set off the explosive.  
B.2.3  The ho le in the lead block expands due to the explosion.  
B.2.3  pour water into the cavity left after the explosion.  
B.2.3  Pour the water into a graduated cylinder to measure the volume.  
B.2.3  The original volume of the hole shall be subtracted to get the volum e of the expansion. Some part of 
the expansion is due to the blasting cap, and this is subtracted from the total as well (as determined by setting 
off the blasting cap with a non -explosive 10 grams of dummy material in a similar block).  
NOTE  Some part of t he explosive energy goes into heating the lead block and the sand. Some part goes into blowing 
away the sand. Some part escapes as the heat of the gases after they leave the block. So what the test measures is not 
the total energy of the explosive, but the  work it does on the lead block ( Capacity for work)  DUS 1756 -2: 2017  
© UNBS 2017 – All rights reserved  7 
 Annex  C 
(normative)  
 
Detonation  velocity  
C.1 Dautriche Method  
The detonation velocity is a measure, in meters per second or feet per second of the speed at which the 
detonation w ave travels th rough a colu mn of explosives.  
C.2 procedure  
C.2.1 The sample of explosive under test is placed in a confinement tube which may or may not be 
surrounded by a steel sleeve.  
C.2.2 The position of two blasting caps along the sample define the part for which the detonation  velocity is 
to be measured.  
C.2.3 The ends of the piece of detonating cord of known detonation velocity are connected to the blasting 
caps and the cord is passed across a lead plate as shown in figure C.1 
C.2.4 The detonation wave in the test sample is in itiated by a detonator or booster at the upstream end of 
the test tube and a steady detonation wave front starts to travel along the confinement tube.  
C.2.5 As soon as the wave hits the first blasting cap (A) a second detonation wave is instantaneously 
initiated at the end of the detonation cord connected to the cap.  
C.2.6 At the same time, the detonation wave in the test sample continues down the confinement tube, and 
eventually, it reaches the second blasting cap (B) positioned at a distance (m)  
C.2.7 This then initiates a third detonation wave in the other end of the detonating cord, Eventually, the two 
detonation wave front in the cord travelling at equal speeds but in opposite directions, collide and produce a 
notch in the lead plate at the point of co llision. Clearly, the time required for the two opposite detonation waves 
to travel from the first blasting cap to the collision point at the lead plate is the same  
  
8 © UNBS 2017  – All rights reserved  
 Figure C .1 — Dautriche Method  of velocity of detonation  
C.3 Calculation  
For the wave goin g directly into the detonating cord of total length of cord (L) the approximate velocity of the 
explosive shall be given by;  
)2(amD D cord sample 
   2 
where 
Dsample  is the  sample is velocity of sample explosive ; 
Dcord  is the cord is velocity of detonati on of cord ; 
m  is the distance between blasting cap A and B ; 
a  is the distance between cord centre and notch after firing . DUS 1756 -2: 2017  
© UNBS 2017 – All rights reserved  9 
 Annex  D 
(normative)  
 
Explosive energy  
D.1 Under water test method/ bubble test  
Underwater blast (i.e. Bubble, Aquarium) test is wide ly used to measure explosive energy. This test is based 
on evaluation of parameters of pressure wave generated by underwater detonation.  
D.1.1  Procedure  
D.1.1.1 A specific mass of explosive is placed at sufficiently great depth in a large pond of clear wa ter. 
D.1.1.2 The explosive is detonated and a generated shock pressure pulse is measured by a suitable 
transducer by placing it at some distance away.  
 
Figure D.1 — under  water test Method of velocity of detonation  
D.1.2  Calcula tion 
Energy in the pressure pulse (energy output of explosive) is given by the following equation;  
 
t
losive dttPWCDRE
0exp )()**()*5.12(  3 
where 
R is the distance between the shot and the transducer ; 
W is the charge weight (Kg) ; 
D is the density of water (g/cc) . 
 
10 © UNBS 2017  – All rights reserved  
 C is the velocity of sound in water (m/s)  
P(t) is the pressure as a function of time  
t is the time constant of the falling pressure pulse (s) and is calculated by dividing the peak pressure 
by e = 2.718 because up to one time constant , pressure fall exponentiall y. 
D.2 Ballistic mortar test  
D.2.1  Method of test  
D.2.1.1 The system for test shall consist of a steel mortar, weighing about 360 Kg . 
D.2.1.2 A measure of available energy per gram of explosive, suspended in an Aluminium frame of 3m 
height.  
D.2.1.3 The mor tar contains a firing chamber (295  cm3) and a steel projectile weighing 18  kg (figure D.1). 
In the firing chamber 10gms of test explosive is detonated with a standard blasting cap and the projectile is 
ejected.  
D.2.1.4 The recoil deflection of the ballisti c pendulum is a measure of energy in the explosive; this is 
usually expressed relative to the standard explosive. Generally Blasting Gelatine (BG), a mixture of 92% NG 
and 8% Nitrocotton, is used as the standard explosive.  
 
Figu re D.1 — Dautriche Method  of velocity of detonation  
 
D.2.2  Calculation   
Strength of the test explosive as a percent of Blasting Gelatine (BG) is given by the following equation  
) cos1() cos1(100 expBAE losive
 4 
DUS 1756 -2: 2017  
© UNBS 2017 – All rights reserved  11 
 where 
Eexplosive  is the energy of explosive ; 
A   is the angle of deflection with the test explosive ; 
B   is the angle of deflection with BG .  
12 © UNBS 2017  – All rights reserved  
 Annex  E 
(normative)  
 
weight strength  
E.1 Absolute weight strength (AWS)  
The ratio of the energies available in a given volume of explosive compared to an equal mass of  ANFO  
Absolute weight strength is given by the following equation;  
ANFOloosive
MEAWSexp
 6 
Where;  
E explosive  = calculated energy of explosive (MJ)  
MANFO = unit mass of ANFO (Kg)  
E.2 Relative weight strength  (RWS)  
This is a measure of the energy availab le per weight of explosive as compared to an equal weight of ANFO. It 
is calculated by dividing the absolute weight strength (AWS) of the explosive by the AWS of ANFO and 
multiplying by 100.  
Relative weight strength is given by the following equation;  
) ()100 (
ANFOAWSAWSRWS
 5 
Where;  
AWS = absolute weight strength of the explosive  
AWS = absolute weight strength of the ANFO  DUS 1756 -2: 2017  
© UNBS 2017 – All rights reserved  13 
 Annex  F 
(normative)  
 
Bulk Strength  
F.1 Absolute Bulk Strength (ABS)  
The energy available in a unit volume of explosive  
losive losive AWS ABS exp exp 
 8 
Where;  
AWS  explosive  = absolute weight strength  
P =density of the explosive (cc)  
F.2 Relative Bulk Strength (RBS)  
A measure of the energy available per unit volume of explosive as compared to an equal volume of ANFO at a 
density of 0.81 g/cm3 ; it is calculated by dividing the bulk strength of an explosive by the bulk strength of 
ANFO and multiplying by 100.  
ANFOlosive
ABSABSRBS100 exp
 7 
Where;  
ABS explosive = absolute bulk strength of explosive  
ABS  ANFO = absolute bulk strength of ANFO   
14 © UNBS 2017  – All rights reserved  
 Annex G  
(normat ive) 
 
Sampling and compliance with this standard  
G.1 Sampling  
G.1.1 Preservation  
All sample s shall be kept in water proof cont ainer/ polythene cover till they are taken for testing to protect  them 
from water and other atmospheric changes.  
G.1.2 Lot 
Samples of ANFO -based blasting explosives shall be drawn from each lot separately for deciding the 
conformity of the lot to the requirements of the specification.  
G.2 Compliance with this standard  
The lot shall be deemed to comply with the requirements of this sta ndard, if taken in accordance with G .1, 
after inspection (see clause 5) and test ing of the samples, for compliance w ith the requirements in clause 4 , 
no defective is found . DUS 1756 -2: 2017  
© UNBS 2017 – All rights reserved  15 
 Bibliography  
[1] Drilling and Blasting of Rocks By E. Lopez Jimeno, C. Lopez Jimino , Ayala Carcedo (1995 -01-01) 
[2] IS 4668 -1985 Ammonium nitrate for explosives  
[3] Rock Blasting: Effects and Operations By Pijush Pal Roy (2005)  
[4] Rotary Drilling and Blasting in Large Surface Mines 1st Edition By Bhalchandra V. Gokhale  
 DUS  1756 -2: 2017  
© UNBS 2017 – All rights reserved  17 
 Certification marking  
Products that conform to Uganda standards may be marked with Uganda National Bureau of Standards 
(UNBS) Certification Mark shown in the figure below.  
The use of the UNBS Certification Mark is governed by the Standards Act, and the Regulations made  
thereunder. This mark can be used only by those licensed under the certification mark scheme operated by 
the Uganda National Bureau of Standards and in conjunction with the relevant Uganda Standard. The 
presence of this mark on a product or in relation to  a product is an assurance that the goods comply with the 
requirements of that standard under a system of supervision, control and testing in accordance with the 
certification mark scheme of the Uganda National Bureau of Standards. UNBS marked products are  
continually checked by UNBS for conformity to that standard.  
Further particulars of the terms and conditions of licensing may be obtained from the Director, Uganda 
National Bureau of Standards.  
 
 DUS 1756 -2: 2017    
 
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Price based on nn pages  
© UNBS 2017 A ll rights reserved