) 

,· 

Subject Number: 

TGR- 1 

U.S. OEPART11ENT OF THE INTERIOR 

OFFICE oF SuRFAcE MINING 

RECLAMATION AND ENFORCEHENT 

Transm1 tta I Number: 

315 

DIRECTIVES SYSTEM Date: 

1/28/87 

Subject: OSMRE Blasting Guidance ~anual 

""" .i 

Approva I: Title: Director 

7 

1. PURPOSE. This directive is to inform ell OSMRE employees of the 

availability of the OSMRE Blasting Guidance Manual. This manual was 

developed to giv~ guidance to regulatory authorities, the public and industry on the use of explosives and the examination and 

certification of blasters. 

2. DEFINITIONS. None 

3. POLICY/PROCEDURES. 

The OSMRE Blasting Guidance Manual.was developed to give guidance to 

regulatory authorities, the public and industry on the use of 

•explosives and the examination and certification of blasters. This 

document also satisfies a commitment the agency made in the preamble 

to the Use of Explosives regulations (48 FR 9801, March 8, 1983) that 

a technical guidance document would be made available demonstrating 

the application of the modified scaled distance equation and 

determination of predominant frequency in the use of the alternate 

blasting criteria found in 30 CFR 816/817.67(d)(4). The manual can 

also b9 used to partially meet the blaster training requirements of 

30 CFR 850.13. 

4. REPORTING REQUIREMENTS. None 

5. REFERENCES. Se~ attached appendix 

6. EFFECT ON OTHER DOCUMENTS. None 

7. EFFECTIVE DATE. Upon issuance 

8. CONTACT. 

OS!'!RE, liFO, Standards and Evaluation Branch, Michael Rosenthal, 

Chief, (303) 844-2756, (FTS) 564-2756. 

OSH For.n 2~-1 6t ~3/i9 
BLASTING GUIDANCE 

MANUAL 

By Michael F. Rosenthal and Gregory L. Morlock 

With contributions by John L. H. Simmance, 

James W. Reil, G. Alan Foster, 

Thomas W. Nowtny, and Dennis A. Clark 

March 1987 

Office of Surface Mining Reclamation and Enforcement 

UNITED STATES DEPARTMENT OF THE INTERIOR 
Figure 1. 

Surface Mine Blasts. 

ii 
TABLE OF CONTENTS 

PAGE 

INTRODUCTION •.••••••••••• .................................... 1 

CHAPTER 1 

Pre-Blast S'urveys • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • 3 

CHAPTER 2 

Blast Vibrations: Basic Principles and Parameters •••.••.• 11 

CHAPTER 3 

Control of Adverse Effects............................... 15 

Airblast. . • • . • . . • • . • . . . . • . • . . . . . . . • • • . . . . • • . . . . • • . . • . • 15 

Flyrock. • • • • • • • • • • • • • • • . • • • • • • • . • • • • • • • • • • • • • • • • • • • • • • 20 

GrOl.li'ld. Motion. • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • 22 

CHAPTER 4 

D811lB.ge • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • 29 

:Definition of Damage. • • • • • • • • • • • . . • • • • . . . • • • • • • . • • • • • • 29 

Airblas t Damage. • • • • . • . • • • • • • • . • • . • • • • . • • • • • • . • • • • • • • • 30 

Flyrock Damage. • • • • . . • • • • . • . . • • • • • • • . • . • • • • . • • • • • • • • • . 30 

Grotmd fution Damage. • • • • . • . . • . • • • • . • • . • • . • • • • • • • . • . • • 31 

CHAPTER 5 

Human Subjective Tolerance ••••• .......................... 35 

CHAPTER 6 

Causes of Excessive Adverse Effects ••••..•••••.•..•••••.• 39 

Airblast. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39 

Flyr'ock............................................... 42 

Grolnld. Motion. • . • . • . • • . . • • • . . . . . • . • . • . . . . . . • • • • • • • • . • • 43 

CHAPTER 7 

Vibration Monitoring..................................... 45 

Airblast Monitoring................................... 45 

Gro\nld Motion Moni taring. • • . • . • . • • • • • . . • • • • • . . . • • • • . . . 48 

CHAPTER 8 

InstnJIIleiltation. • • • • • . • • • • • • . • • . . • • • • • • • • • . • • • • • • • . • • • • . • 55 

The Peak Recorder. . • • . . • . . . • . . • • • . • • • . • . • . . • . • • . . • . . • . 55 

The Wavefom Recorder •••••••.. ·• • . • . • . • . • . . . • • • . . • • . • . . 57 

iii 
Table of Contents - Contd. 

PAGE 

CHAPTER 9 

Compliance Options Available to the Operator ••••••••••••• 73 Option 1: Maximum Peak Particle Velocity .••..••••••..• 74 Option 2: Scaled Distance Equation •••.••••••••••••.••. 75 Option 3: !~fied Scaled Distance ••.••••••••••••••.•• 76 Option 4: Blasting Level Chart •....•.•.•..••.•..•••..• 80 

CHAPTER 10 

Prediction and Control Methods ••..•....•....•..•.•..•.••• 85 Predictive data: Usage for Modified Ds •••••••••••••••• 88 Predictive data: Usage for Blasting Level Chart and General Predictive Purposes •••••••••..••••.•••••• 90 

CHAPTER 11 

Frequency Considerations .•.•.•...•.•.•..•.•.••.••••.••••• 93 

CHAPTER 12 

Record Keeping. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101 

CHAPTER 13 

Citizen Interests. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109 

Rights and protections under OSMRE regulations •••••••• 109 The prevention of injury to persons •••••••••••••••.••• 110 

The prevention of damage to property •••••••••••••••••• 111 Pre-Blast S\lrVeys ................................... •. 113 Blas~ing times and schedules ...............•...••.•... 114 Perceived blast vibration effects ••••••••••••.•••••••• 115 Actual blast vibration effects •.••••.•••.••••••••••.•• 116 

Armoyance • ••••••••••.••••••.•••••••••.••••••••••• ·•• • • • 117 

Actual blast damage criteria •.....•..•.•••..•.•.••.•.• 120 Specific complaint procedures ......................... 122 

Regulatory Authorities. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124 

APPENDIX I A I 

Regression .Arlalysis •••.• , •.•••.••.•.•••••.••••• , • • • . • . . • • 131 Notes on data collection •.•.•..••.•••.•.•••.•.•••.•.•• 133 Notes on data recording •. , .....•.•.• , .•.•• , • • • • • • • • • • . 133 

OSMRE approv~ regression analysis program: LISTING. • • 135 

OSMRE approved regression analysis program: USE. • • • • • • 150 OSMRE approved regression analysis program: EXAMPLE ••• 151 Notes on Vibra-Tech regression analysis program ••••••• 156 

Example of Vibra-Tech regression analysis (same data 

as in OSMRE program above) ....................... 158 Example of regression curve (VTE analysis same data) •• 161 

iv 
Table of Contents - Contd. 

APPENDIX 'A' (Continued) 

Example of "Blaster Aid" Curve (VTE analysis etc.) .••••.. 162 Vibra-Tech regression analysis calculator program ••••.••• 163 

APPENDIX I B I 

Useful Foillllllae. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 169 

APPENDIX 'C' 

Glossary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 173 

APPENDIX I D I 

Bibliography. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 199 

FIG. 

1. 

2. 

3. 

4. 

5. 

6. 

7. 

8. 

9. 

10. 

11. 

12. 

13. 

14. 

15. 

16. 

17. 

18. 

19. 

20. 

21. 

22. 

23. 

24. 

25. 

26. 

27(a). 

27(b). 

27(c). 

IWJSTRATIONS AND FIGURES 

Surface Mine Blasts .•.•.•••...•.••.....••...••.•..••.•..• Pre-blast Survey: Documenting defects •..•.•.••.••••.••••• Tape recording defects . ................................. . 

Pre-prepared inspection form .. .......................... . 

Pre-prepared inspection fonn . ........................... . 

Surface and 'bcxly waves . ................................. . 

Types of ground motion vibrational waves .••...•...•••...• Compression, tension and shearing effects .••.•.••••••.••. Vibration parameter relationships ..•....•..•..•..••...••. 

Relationship between dB linear and psi ••.•••••.••••••••.• Explosive casting . ...................................... . 

Alternative blasting level criteria .••••.•••..••••.•••... Good public relations efforts assist subjective problems. Weather effects on airblast •...••...•••.•.....••.••.••••. Weather effects on airblast ..•••.•••••....•...•..••.••.•• Weather effects on airblast •.••....••.•..••..••.••..•..•• Weather effects on ai.rblast. I •••••••••••••••••••••••••••• 

Proper stemming effectively reduces airblast ••••...•••... Field rnoni toring . ....................................... . 

Monitoring ground motion and air blast •••..••••••.•••.•.• Instr1..1Plent placeinent I •••••••••••••••••••••••••••••••••••• 

Sandbag & spike transducer head to achieve good coupling. Dallas InstrtliTlents VS-3 . ................................ . 

Dallas InstrtUllents BT-4 . ................................ . 

Dallas Instrl..lJJlents ST-4 .. . I •••••••••••••••••••••••••••••• 

Dallas Instruments ST-4D .•.•••..•...••••..••••.•..•.••••. Digital Vibration Teleblast ••.•.•..•••....•••..•..•.••.•• Digital Vibration Teleblast •.••..••..••••••.•••..••.•.••• Digital Vibration Teleblast ••••.•••.••••••..••...••.•.••. 

v 

PAGE 

ii 

3 

7 

Sa 

Bb 

11 

12 

13 

14 

17 

20 

24 

36 

40 

40 

40 

40 

41 

46 

48 

49 

51 

63 

63 

64 

64 

65 

65 

66 
Illustrations & Figures - Contd. 

FIG. PAGE 

28. Philip R. Berger & Associates SSU II •••••..••••.•..••••.. 66 29. Philip R. Berger & Associates SSU 10000 ...••••.•.•••••..• 67 30. Slo}:)e Indicator S-2 .................... , ... ,, .. ,, .. ,,,,., 67 

31. Slope Indicator S-3...................................... 68 32. Slope Indicator S-6...................................... 68 33. Sprengnether Instruments VS-1200 ..••••..•••.•••...•••.••• 69 34. Sprengnether Instruments VS-1600 ...••..•....•••..••.•..•• 69 35. Vibra-Tech/VME Vibra-Tape GMS-4 .•••.•••••••••.••••••••••• 70 36. Vibra-Tech/VME Series 5000............................... 70 37. Vibra-Tech/VME Seistector •..•••...••..••.••••...••••.•••. 71 38. Vibra-Tech/VME VR Model F................................ 71 39. Vibra-Tech/VME VR Model G. . . • . . . . . . . . . • . . . . . . . • . . . . . . . .. • 72 40. Typical computer printout of blast vibration waveforms .•• 80 41. Calculation of frequency for a simple waveform •••.•••..•• 94 42. Fourier amplitude spectrum for a simple waveform •.•••••.• 95 43. Analog waveform with high and low frequency components ..• 95 44. Analog waveform with two frequencies showing the effect of phase relationships. • • • • . . • • • • . • • . . • • • • . . • • . . • • . . • . . 96 45. Calculation of frequency for a waveform with two 

pre.dominatlt frequencies. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96 

46. Restuts of digital filtering •••.•.•.•.•••..•.••••..•••..• 97 47. Fourier amplitude spectrum for a waveform with two 

predominarlt frequencies................................ 97 48. Analysis of blast vibration waveform with three frequency components. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98 

49. Response spectrum of a blast vibration waveform with 

three frequency components •.•..••..••••.••..••..••••.•. 99 SO. Typical blast record form .....•....••...........•••...... 103 

51. Blasting report (1). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104 

52. Blasting report (2). • • • . . . • • • • • . . . • • . . • • • • . . • . • . • • . . • • • • • 104 53. Typical blast and seismograph record form (1) ••..•••••••• 105 54. Typical blast and seismograph record form (2) •.•••••.•••. 106 55. Typical pre-blast inspection forms ..•••••••••..•••.•••••. 107 56. "Eaglefeather Mine, Blackrock, Wyorado" .•••...••....•.•.. 131 

TABLES 

TABLE PAGE 

1. Factors Which Influence Ground Motion •••..••••••.•..••••.• 27 2. Factors Which Influence Airblast .•.•••...••••.•••••••••.•• 28 3. Human activities and equivalent ground vibration levels ••• 33 4. Instnnnentation . .......... , ........................ , . . . . . . 61 

vi 
BLASTING GUIDANCE MANUAL 

INIRODUCIION 

The Office of Surface Mining Reclamation and Enforcement 

(OSMRE) Permanent Regulatory Program Sections 816.61-68 and 

817.61-68, as published in the Federal Register on March 8, 1983, 

will be referred to henceforth simply as the OSMRE regulations. 

They were designed to protect the general public against the 

possible negative effects of surface mining as a whole. Throughout 

this document reference will always be made to Section 816 alone 

for the sake of clarity, since the detailed paragraphs in both 

Sections are identical. '~enever such reference to Section 816 is 

made, it is to be understood that equal reference is made to 

Section 817. 

This Gvidance Manual deals particularly with the negative 

effects of blasting, and applies to all blasting, regardless of the 

total weight of explosives detonated. The only variance allowed, 

under Section 816.61(b), is that blasts under 5 lbs. in total 

weight do not have to comply with the Blasting Schedules otherwise 

required under Section 816.64. 

The intent of Congress in the Act [Public Law 95-87,(Act), 

Section 515(b)(l5)(c)] was to prevent (i) injury to persons, (ii) 

damage to public and private property outside the permit area, 

(iii) adverse impacts on any underground mine, and (iv) change in 

the course, channel, or availability of ground or surface water 

outside the permit area. No regulation can circumvent the will of 

Congress. This therefore means that the OSMRE regulations apply to 

all surface coal mine operators, whenever they blast. 

However, this Manual is also intended to make compliance with 

the OSMRE regulations as easy, practical and as beneficial to the 

operator as possible, while still affording the environmental and 

safety standards required by the Act. It will show that compliance 

is not only a matter of observing perhaps onerous restrictions, but 

also that there are definite advantages that can accrue from such 

compliance. These advantages, if fully exploited, will in part - or even entirely - offset the cost of compliance. They could 

improve the efficiency of blasting operations, lower explosive 

costs, cut drilling costs, and generally improve profitability. They will certainly improve safety. 

This Manual will also address the several different ways in 

which compliance may be effected, always at the option of the mine 

operator. It will attempt to explain the relative merits of each 

method, in practical everyday terms. 

1 
Introduction 

In addition to this, the Manual is offered as self-training for the control and prediction of blasting effects, and as a 

partial basis for self-study for OSMRE blaster certification. It 

is presented as a source of up-to-date information on damage criteria and state of the art methodology for those who find 

themselves in the position of having to formulate blast vibration 

ordinances. Last, but not least, the Manual is intended to provide 

a basic reference and field guide for OSMRE inspection and 

enforcement personnel. 

A study of the adverse effects of blasting will be covered in 

detail: ground vibration, airblast and flyrock, and the methods 

by which these effects can be monitored and controlled will be 

described. Pre- and Post-Blast Surveys, Instrumentation, Record 

Keeping and some of the subjective human issues that greatly influence our activities will be discussed. If these principles and lessons are applied to all everyday activities in surface coal 

mining, it will not only be found that the OSMRE regulations are 

complied with, but it will also: 

• Improve public good will 

• Enhance the public image of a surface 

coal mining operation 

• Reduce complaints 

• Avoid most lawsuits 

• Win unavoidable lawsuits 

• Improve blasting efficiency 

• Reduce costs 

• Increase profitability 

• Improve safety 

• Mitigate the adverse effects of blasting 

2 
CHAPTER 1 

PRE-BLAST SURVEYS 

REX:)UIREMENT BY LAW: Unlike many other sections of the OSMRE 

regulations, the requirement to carry out pre-blast inspections of 

properties within one half mi-le of the permit is specified in the 

original Public Law 95-87, August 3, 1977, (Section 515(b) 

(15 )(E)). The Act states the "The Regulatory Authority •.•. shall 

include provisions to provide that upon the request of the resident 

or owner of a man-made dwelling or structure within one-half mile 

of any portion of the permitted area the applicant or permittee 

shall conduct a pre-blast survey of such structures and submit the 

survey to the regulatory authority and a copy to the resident or 

owner making the request". 

Figure 2. 

Pre-blast Survey: Documenting defects. 

3 
Pre-Blast Surveys 

OSMRE REGULATIONS: The specific requirements of the 

pre-blasting survey are included in Section 816.62 of the OSMRE 

regulations. The operator is required to carry out an inspection of any dwelling or structure within one-half mile of the permit 

area if requested in writing by the owner or resident. The owner 

or resident must be contacted by letter at least 30 days before the 

start of blasting, notifying them how they may request a pre-blasting survey. The final written inspection report must be 

signed by the person making the survey and copies are to be provided both to the regulatory authority and the person requesting the survey. Since the operator will want to keep a record of each 

survey, as also will the independent consultant carrying out the 

survey, if employed, this means that at least 4 copies will be required. 

The survey report must determine the condition of the dwelling 

or structure and must document any pre-existing defects and other 

physical factors that could reasonably be affected by the blasting. Structures such as pipelines, cables and transmission lines, also cisterns, wells and other water systems warrant special attention; however the assessment of these structures may be limited to visible surface conditions and other readily available information. 

The main intent of the pre-blasting survey is to provide independent documentation of the existing physical condition of the 

structure with the location and the dimensions of each observable 

defect clearly noted. 

CAUSES OF STRUCWRAL DEFECTS: Minor defects in structures such as cracks in plaster, masonry and other structural materials 

are extremely common and are usually the result of the relative 

movement of the different materials of construction with changes in 

temperature and humidity. Other more serious defects can result from other causes and the United States Department of the Interior, Bureau of Mines, has published in Bulletin 442, "Seismic Effects of 

Quarry Blasting", a list of forty causes of cracks appearing in 

walls and ceilings. 

None of the following causes are related to the application of explosives; however, the horneolmer often becomes so sensitized by 

the perceived effects of blasting that he believes that many long standing defects in his dwelling are the result of blasting. These 

40 causes are listed as follows: 

1. Building a house on fill. 

2. Failure to make the footings wide enough. 

3. Failure to carry the footings below the frost line. 

4 
Pre-Blast Surveys 

4. Width of footings not made proportional to the 

load they carry. 

5. The posts in the basement not provided with 

separate footings. 

6. Failure to provide a base raised above the basement 

floor line for the setting of wooden posts. 

7. Not enough cement used in the concrete. 

8. Dirty sand or gravel used in the concrete. 

9. Failure to protect beams and sills from rotting. 

10. Setting the floor joists one end on masonry and 

the other on wood. 

11. Wooden beams used to support masonry over openings. 

12. Mortar, plaster or concrete work allowed to freeze 

before setting. 

13. Braces omitted in wooden walls. 

14. Sheathing omitted in wooden walls (except in 

"Back-Plastered" construction). 

15. Drainage water from roof not carried away from the foundations. 

16. Floor joists too light. 

17. Floor joists not bridged. 

18. Supporting posts too small. 

19. Cross beams too light. 

20. Subflooring omitted. 

21. Wooden wall not framed so as to equalize shrinkage. 

22. Poor material used in plaster. 

23. Plaster applied too thin. 

24. Lath placed too close together. 

25. Lath run behind studs at corners. 

26. Metal reinforcement omitted in plaster at corners. 

5 
Pre-Blast Surveys 

27. Metal reinforcement omitted where wooden walls join masonry. 

28. Metal lath omitted on wide expanses of ceiling. 

29. Plaster applied directly to masonry at chimney stack. 

30. Plaster applied on lath that are too dry. 

31. Too much cement in stucco. 

32. Stucco not kept wet until set. 

33. Subsoil drainage not carried away from walls. 

34. First coat of plaster not properly keyed to backing. 

35. Wooden beams spanned too long between posts. 

36. Failure to use double joists under unsupported partitions. 

37. Floor joists placed too far apart. 

38. Too few nails used. 

39. Rafters too light or too far apart. 

40. Failure to erect trusses over wide wood openings. 

CHANGES IN CONDITION WITH TIME: Any or all of these listed causes may result in cracks or defects. As time passes, dimensional changes due to seasonal temperature and humidity fluctuations can be expected to render those defects more visible, or to widen or lengthen cracks. The causes of the defects, if uncorrected, will continue to have an effect even after the pre-blast survey has been completed. It is, therefore, very important that any structural defects or conditions which could be expected to worsen with time should be clearly identified. The homeowner or resident of any property should be made aware that such changes can oc=, and why they occur, or they may be incorrectly attributed to the blasting vibration effects. In some cases the presence of serious structural problems may necessitate that lower vibration levels be imposed on a particular structure to prevent further deterioration. These structural defects or problems must be documented in any report. 

INSPECTION PROCEDURES: The OSMRE regulations do not specify who should carry out the pre-blast inspection. In most cases they will be carried out by an independent consultant specializing in 

6 
Pre-Blast Surveys 

the field of blasting vibrations and their effects on structures. The use of an independent consultant will avoid any problem of 'conflict of interest' that might arise should the operator's own 

personnel be used. If practical, the homeowner or resident should 

accompany the inspector during the inspection so that they are made 

aware of the procedures, and the defects noted. 

If accompanied by the homeowner or resident, maximum benefit 

may be derived from the required survey if the inspector uses the opportmrity to establish a positive public relations image. Not only should the procedures be described, but if possibilities exist that the blast vibrations will be, or have been, perceptible at the dwelling, these subjective effects should be frankly discussed and 

the perceived effects explained. 

In conducting a pre-blasting survey of a building it is essential to document the location, length and width of any crack 

or other defect which may be visible on both the interior and 

exterior surfaces of the building. 

Figure 3. 

Tape recording defects. 

Various techniques are used to carry out pre-blasting surveys including recording the defects on video tape, audio cassette tape or by hand written notes either in narrative form or on a 

7 
Pre-Blast Surveys 

pre-prepared form. In nearly every case photographs are also used 

to document the major defects present, or to support the 

descriptive text. 

In recent years video tape recording has become more popular but in most cases the lack of resolution in all but the most 

expensive equipment and the need to use additional lighting has 

limited its use for interna1 inspections. The OSMRE and Public Law 

95-87 requirement that a written report of the pre-blast inspection be provided rules out the use of video tape except as a 

supplementary form of documentation. As video tape equipnent improves and becomes more portable it might be that inspections using this method may become more acceptable. In addition to this 

consideration, however, in order to satisfy the Law on copies, it 

would be necessary to provide copies of the video tapes to all 

recipients. This might prove to be an unacceptable additional cost. 

The most popular and accepted methods presently used by consulting firms and industry to carry out pre-blast inspections 

are tape recorded notes in narrative form, later transcribed in a 

typed report, augmented by photographs of each of the significant defects. They can also use prepared forms or wall/ceiling diagrams supported by hand written notes and photographs. 

Examples of these inspection types and of typical pre-prepared forms are shown in Figures 2, 3, 4 and 5. 

8 
VME - NITRO CONIULT, INC. SHEET ___ OF --- .................................. FIELD REPORT 

EXISTING STRUCTURAL CONDITIONS 

CL.LI!NT TOWM: 

INI,.I!CTOIII; JOB NO INSPECTION NO. 

DATI: ·" TIME 01" INSPECTION: ........ o P,M,Q 

COMPLI!TI!Q INTI!fii:I01110 EXTI!III!Ofii:Q MI"USAL0 IUIIIVEY OONI!: .1!,.01111!.0 AI'T!!IIId DUIIIINGO 

OCCUPANT OWNEIIIO TI:NANTQ 

AODIIIRSII I!STIMATI! • AGI! TI!ARS 

OWNI!IIt. ADDIIIDa 

OIMIUL DUCIIItTIOM 

P'OUNOATION' C:ONCIIIUI!Q COt!. BL.OCK D !I"ICKQ OTHI!I'I:Q 

HOUSE SIDING CONDITION: ooooO AVG.Q POOIIIO 

.... CONDITION: aoooO AVO.O POOIIIO 

CHIMNI!Y CONDITION: ooooO ... vo.o ~01110 

NUMBI!III 01" ITO .. II:S PICTU"I! NO, 

~IIICH • I 

·~· I • HOUSE LENGTH WIDTH 

•ROKI!N GLAU ·---·--· __ ._____ NATU1'1tl! 01" Gfii:OUND 

SIOIIWALICS • --· --·--·--- I"LAT0 HIL.LYQ l'"n.L.O 

MOIIITAIII JOINTS aoooO Ava.o POOIIIIO WATI!III PAI!.SSUIIII!; HIGHO L.owO MI!O Q 

WATI!III: CITYO WI!LLQ OTHI!IIIQ WATER QUAI..ITY: CL.EAR 0 MILKY 0 IIIUSTY 0 

BAIIIM&NT YI:IO ••0 

1001' AND DIAIU.OI 

MAIM 111001'~ Dfi:AINAOE AO.QUATI: nsO ••O ~fi:CH Dfi:AINAOE: vnO ••0 

OUTTI!fl:l Vl:s0 ••O CONDITION LOT Clfi:AINAOE I'LOWI 

.... n•D ••0 CONDITfON 

.... DJIAINI TO: I:A"TH0 TlltOUOHQ CATCHaASIN 0 IIIWI:fi:Q 

ElltOIION NIIAIIl I'OUNDATION WALL vuO ••0 I COMMI:NT II' Vl!l I 

WALL ALIOMMI:NTI IT MIGHT 0 •O •O •0 •O 

.UILDINO HTTLII nsO ••0 I COMMI:MT II' Vl:l I 

HOUMI'ACIII •0 •0 •0 •0 JOIST: .... /C LI:VI!L afi:IDGII .... .IPICTOI1 "'JOVID aY I 

KllV 01' IVMMJLIJ C"-"CK--

NAil. 'Of'-

HPAitATlON-IIIJI UNL&YIIL I'LOOM - Ul' ~~~~-~ 

.. aADI .... M-- •liNT wALL. - aw HAUIILINI:-HL I'IHfl:aGAJIO- ~· UNLaVI:L CI:ILINCI- UC IH.Ufi:OCK- Sf!: CONCfi:I!Tf:-CONC, •uiLCMNII- M.O CONCIIITIILOCII: - CQHC. IL .....,_, .......,_., IUINHDID TILl: -IT 

__ ,. f~TION -!'ON III"AL1MG - ..... 

VINYL 

ACOUITJCAL TILl-TillVT AT ~ANIUHG-I'l _......,_,.,. IIIIIOKIN OI.AII- 10 NI!UNQ 1'.-,Nr - "' 

wooo-wo WATIJIIT.-,NI- WI 

CI!RAMIC TILE- CT MORTAFIJOINT SI!~ARATION -MJS 

co.-a 1e01 

Figure 4. 

Sa 
VME - NITRO CONSULT, INC. SHEET __ OF __ 

FIELD REPORT 

EXIITING STRUCTURAL CONDITIONS 

SUBJECT: INSPECTION NO.: 

Floor: 

Room: Sin: W1llt: C.lllng: 

I D· 

COMMENTS' 

Floor: Room: Sin: W1ll1: Ceiling: 

i I I· 

COMMENTS' 

Floor: Room: Size: Wall1: Ceiling: 

I D· 

COMMENTS< 

Floor: 

Room: Size: Wills: Ceiling: 

..... .... ...... Won 

I D· 

COMMENTS: 

DATE OF INSPECTION: __ ,IO_INSPECTOR: ______ .APPR. BY:-----

COL-2 ('H) 

Figure 5. 

Bb 
Pre-Blast Surveys 

An important function of the pre-blast survey is that of 

recording existing problems that might be expected to deteriorate 

independent of any blasting. Noting the fact that a building might be historically valuable or fragile is sometimes overlooked; as is 

noting the presence of unusually costly or vulnerable contents. The 

OSMRE regulations protect persons and property, and it may be 

forgotten that the property at risk might be a particularly vulnerable building, or even the contents of that building. 

Section 850.13(b)(l0)(iii) refers to training in the "use of 

pre-blast surveys in blast design". In all normal situations, of 

course, a pre-blast survey has no direct bearing on blast design. The survey records pre-existing defects, While the blast design, 

among other considerations, ensures that vibrations do not exceed 

regulatory limits. 

However, should that structure be a historical building, for 

example, containing valuable collections on exhibit, then special considerations might have to apply. Vibrations that would present 

no threat of even cosmetic damage to a modern building, might cause 

damage to a very old structure, and could possibly cause fragile contents to fall and break. Under circumstances such as these, blast design can indeed be dependent on the pre-blast survey. 

In terms of protecting contents, much will depend on 

individual circumstances. Apart from the nature of the valuables, the type of support or mounting is of significance. Inclined or 

shaky shelves or cabinets, or insecure wall mountings will present breakage risks quite apart from blasting vibrations. No great -threat would normally be imposed by regulatorily compliant vibrations, provided mountings or supports were stable, level, and 

in good condition. It would obviously be unnecessary to impose special restrictions on blast design if it were only that a 

householder had a collection of porcelains in cabinets, for 

example. In a case like this, however, it would nevertheless be 

appropriate to warn the householder, and advise that such valuables 

be placed in safe places. Double-sided foam mounting tape cart often 

provide a secure answer to this type of problem. 

The final written report, together with any copies, must 

include any photographs of the visible defects. These photographs 

may be either black and white or color but must be of such a size 

that the photographed defects can be seen by the naked eye. 

The inspections of cisterns, wells, etc., may be limited to 

"surface conditions" but all available data should be documented, including in many cases a chemical analysis of the water supply. Historically, many wells have been shown to vary in volume and 

water quality, and, in some cases, a separate hydrologic study may be of value. If blasting commences at a time when a seasonal flow 

reduction is usual, a separate water report will prove invaluable. 

9 
Pre-Blast Surveys 

Post-blasting surveys are normally required only in the event 

that a homeowner or resident makes a specific blast-related damage claim. A post-blasting survey, then, will be based on the 

particular damage claim, and will serve simply to confirm or deny the validity of the damage claim. The complaint damage itself 

should be inspected, documented and photographed if necessary, and 

comparison reference should be made to the original pre-blasting 

survey report. Note should be taken of whether the original report listed the defect and whether the original report listed any 

structural or other conditions that might have led to the 

appearance of the defect independent of any blasting activity. For 

this reason, particularly if the conclusion of the post-blasting 

survey might be to deny the damage claim, it is preferable that it 

be conducted by an independent specialist consultant. 

SUMMARY: A pre-blasting survey, to be of real value, has to 

be done with care ensuring that no observable defects are omitted. 

A poor inspection in which defects are omitted will be of little 

value to an operator. In many cases, homeowners are unaware of all 

the defects present in their homes, but the sensitivity of human 

beings to vibration effects from blasting can result in their 

inspecting their homes more closely than usual and perhaps noticing pre-existing defects for the first time. It should also be 

remembered that the homeowner will have a copy of the pre-blasting 

survey report. 

If local public relations are not good, or if relations between 

the mine and the homeowners are strained, it could be that a , homeowner will apply himself to discover a missed defect. He may have several weeks in which to conduct such a search, compared to 

the hour or so available to the original inspector. Such defects, unless recorded in the pre-blasting survey, could logically be 

expected to have been caused by the blasting. It is exactly for 

this reason that a good pre-blasting survey should not only contain 

the location and type of each existing defect but also some 

comment, where possible, on existing structural problems which 

could be expected to cause further new defects or the worsening of 

existing defects. Typically, houses are not engineered structures, and some deterioration can be expected from the day the structure 

is built, largely because of the wide variety of materials used in 

their construction. Each material undergoes differential expansion and contraction with changes in temperature and humidity and some 

materials such as plaster undergo internal chemical changes with 

age which can reduce their physical strength. Although such changes 

are to be expected, there is no doubt that a good pre-blast inspection provides good baseline data on which to judge the 

validity of a claim of alleged blasting damage, and serves to 

protect both the interests of the operator and the property owner. 

10 
CHAPTER 2 

BLAST VIBRATIONS: BASIC PRIN::IPLES AND PARAMETERS 

When a blast is detonated, a great deal of energy is liberated. In a well designed blast, most of that energy will be 

spent in breaking rock, but some will be converted into vibrations, either grotmd motion or air overpressure ("air-blast"). In a badly 

designed blast, where poor breakage is obtained, or where the holes are over or under loaded, it can be that nruch of the liberated energy is converted into vibrations, since it is not expended in fragmenting the rock, as it should be. 

Ground motion is the principal vibration that will result from blasting, though airblast may be more noticeable because of the accompanying noise effects. The ground motion is literally a wave motion spreading outwards from the blast, much as the ripples spread outwards from the impact of a stone dropped into a pool of 

water. The earth, or rock, through which this wave travels is considered to be an elastic medium, composed of innumerable individual particles. As a disturbance occurs, each of these particles are set into a random oscillatory motion about their rest positions, a wave being generated as each particle transmits energy successively to the next. Energy losses occur with each successive transmission, so that as the vibration wave spreads outward, it diminishes in intensity, and the particles gradually return to their rest positions. 

Slnlctll't 

Blut 

&rface Waveo: P & S 

Figure 6. 

Surface and· body waves. 

11 
Blast Vibrations 

Particle motion is generally classified into two broad divisions; body. waves and surface waves, as shown in Figure 6 on the previous page. Body waves may be reflected or refracted to the surface to became surface waves. Further classification will 

identify Rayleigh waves, with a circular or rotational movement and also 'p' waves - compressional waves -and 's' waves that have 

a shearing action (Figure 7). Ground motion consists of a combination of all these wave forms. This manual does not intend 

to discuss this subject in detail, but will refer to it briefly, in 

terms of possible damage effects. 

The abbreviation are u followa: 

SH-Shear wavt, horizontal 

SV-Shear wave, vertical 

R -Rayleigh wave 

P -Comprutlon wavt 

T -Tranaver" direction of meuurement 

R -Radial dirtction of mueurement 

V -Vertical direction of meuurement 

Figure 7. 

re±= 

:~ v Geophone 

Types of Ground Motion vibrational waves. 

The ways in which these waves can affect buildings and 

structures on the surface, through compression and tension, and through vertical and horizontal shearing effects, are illustrated in Figure 8, opposite. 

There are several ways in which the intensity of these waves 

can be measured: 

DISPLACEMENT is the actual distance over which a particle moves when set in motion by a seismic wave. It is the basic rationale in the 'sloped' portions of the Blasting Level Chart [(Section 816.67(d)(4)(i), see Figure 1 (Manual Figure 12) in Chapter 3, page 24 of this manual] below 4 Hz and between 11 and 30 Hz. It is rarely used nowadays as the sole parameter for ground motion. 

VELOCITY is the speed attained by any individual particle during the course of its oscillatory motion, and in the past this 

12 
Blast Vibrations 

has been determined to be the most significant single parameter, in terms of damage possibility. Langefors and Kihlstrom in Sweden, Edwards and Northwood in Canada, and in the United States, the USBM (Bulletin 442 and 665; RI 8507 and 8896) have all used Peak Particle Velocity as the fundamental and principal damage possibility parameter. There is no doubt whatever, in spite of some ongoing argument, that the Peak Particle Velocity, considered in conjunction with the the frequency and duration of the blast vibration, is the most appropriate and accurate indicator of possible blast damage. Incidentally, Seismic or Propagation Velocity is the velocity at which a wave passes through the earth, and must not be confused with Particle Velocity. The two are easy to distinguish: seismic velocity is very fast, thousands of feet per second, while particle velocity is very slow, even damaging particle velocities being measured at only a few inches per second. 

no oUoct or P-w .. o •••••••Uoo 

Co•'""'" T ...... 

Tho ortul 

~~ ol 8-w .. o "'''lotio• 

Figure 8. 

Compression, tension and shearing effects. 

ACCELERATION is the rate of increase in velocity of a vibrating particle, as it oscillates about its rest position. In some instances, acceleration is of interest in terms of blast vibration, but it does not generally concern surface coal mining, unless blasting is carried out close to electro-mechanical devices, relays, tape systems or computer installations, which are sometimes specified for a maximum acceleration level. 

Figure 9, overleaf, shows the relationships between these three basic blast vibration parameters. These relationships also introduce frequency as a common variable factor. Frequency alone is of no consequence, but when considered in conjunction with 

13 
Blast Vibrations 

either particle velocity or displacement, recent studies have shown 

that frequency has a very considerable effect on the possibility of 

blast vibration damage. USBM publications RI 8507, and the work of 

Dr. Kenneth Medearis, both stress the importance of frequency, 

while the present OSMRE regulations on scaled distance and maximum 

peak particle velocity are based on the effects that low 

frequencies have on damage possibilities, when using peak particle velocity as the basic parameter. 

u Displacement U= A sin" wt U•A sinwl 

A...m&l! =A sin "12 =~ 

v 

Velocity 

V:Av cos w1 V=A,.,.cos..t 

.Y...!!w= 2.,.f A cos 0=12wfAI 

Acceleration 

a .. v sin wl a=,.<sin ... t 

a max= 4'lY1 1 

1 A {inches/second/second} 

l...l!!ll!= 4t'r' A sin Of/2 = 14'1F'r1 AI 

Figure 9. 

Vibration parameter relationships. 

Vector sum, or resultant velocity, is not normally used as a 

parameter any longer. Some instruments still show resultant 

velocity, instead of the maximum of any plane. This will present 

no problem in terms of simple compliance, since a vector sum, if 

not equal, will always exceed the maximum in any plane. Some 

authorities still write specifications in terms of "ENERGY RATIO" 

which is calculated from a true resultant velocity. This should 

not normally concern the surface coal mine operator; however, as a 

point of interest, if he should wish to calculate a resultant 

velocity, a TRUE resultant velocity will be calculated from peak 

measurements in all three planes, WHICH IVERE RECORDED Kr THE SAME 

INSTANT OF TIME. If the calculation is made from the maximum peaks 

that occurred in all three planes during the course of the entire 

event, it will provide the PSEUDO RESULTANT VELOCITY instead. 

Formulae for calculating the relationships between peak 

particle velocity, displacement and acceleration are provided in 

the "Useful Formulae" Section of Appendix 'A', on page 169. 

14 
CHAPTER 3 

CONTROL OF ADVERSE EFFECTS 

Blasting carried out at surface coal mines, and at some of the 

entries of, or for facilities at certain underground mines, will 

always cause some degree of "adverse effects". Just how adverse 

these effects might be depends on how close the blasting is to 

people and property. What is adverse in one case may not be in 

another, and except in the case of flyrock, negative subjective 

response by the public to the mining operation can be a major 

factor. 

The OSMRE Regulations (Section 816.67(a)) state: ·"Blasting 

shall be conducted to prevent damage to persons, damage to public 

or private property outside the permit area, adverse impacts on any 

underground mine, and change in the course, channel or availability 

of surface or ground water outside the permit area." 

There are three main adverse effects of blasting: 

• Airblast 

• Flyrock 

• Ground motion 

(Section 816.67(b)) 

(Section 816.67(c)) 

(Section 816.67(d)) 

These effects will be discussed together with some typical 

damage possibilities. 

AIRBLAST 

COI!IllOilly known also as "air overpressure". The Bureau of 

Mines Publication IC 8925 "Explosives and Blasting Procedures 

Manual" describes airblast thus: "An airborne shock wave resulting 

from the detonation of explosives. May be caused by burden 

movement, or the release of expanding gas into the air. May or may 

not be audible. " If the total energy in the shock wave is lm.;, but 

the predominant frequencies are well within the range of human 

hearing (16-20,000 Hz ±) then although a LOUD event might be 

heard, it might not record very high in terms of dBL or psi. 

Conversely, a very low frequency event, say predominantly 6 Hz or 

so, would be virtually inaudible, yet might register very highly as 

an airblast event, and even possibly cause damage. 

The "loudness" of an event is no real indication of how "high" 

it is or Whether or not it could have caused damage. 

For years, airblast was considered a minor problem. For 

15 
Control of Adverse Effects 

example, Bureau of Mines Bulletin 656, for years the industry's standard on blast effects, dealt with the subject on less than ten 

pages, the subject chapter being only four pages long. Real structural damage resulting from airblast is not only usually 

minor, but very rare. Window breakage is normally the first and only damage to result from airblast. Subjective response to airblast, however, can make it the most significant of any of the three adverse effects. 

Concern regarding noise pollution generally during the early 1970's involved the U.S. Bureau of Mines in a study Which resulted in early standards and instrumentation guidelines. During the same period, and preceding the Act of 1977 and the OSMRE regulations, the industry and blast vibration consultants, together with the 

state agencies, came to realize the importance of airblast. Instrumentation was developed that monitored airblast, together with or separately from ground motion, and standards were defined and consistency developed between states. 

The OSMRE Regulations (Section 816.67: Use of Explosives: Control of Adverse Effects) refers to airblast in paragraph (b) which states: 

(b) Airblast - (1) Limits. (i) Airblast shall not exceed the ~namum limits listed below at the location of any dwelling, public building, school, church, or community or institutional building outside the permit area, except as provided in paragraph (e) of this section. 

Lower Frequency Limit of 

Measuring system, in Hz. 

Max. Level in 

dB (±3dB) 

1Hz or lower--flat response<l> ••.•....•.•.... l34 peak 2Hz or lower--flat response .•••..•.••••.•.••. l33 peak 6Hz or lower--flat response ....•.••••..••..•• l29 peak C-weighted --slow response<l> •..•••••••.••.• lOS peak dBC 

<1> Only when approved by the regulatory authority. 

(ii) If necessary to prevent damage, the regulatory authority may specify lower maximum allowable airblast levels than those of paragraph (b)(l)(i) of this section for use in the vicinity of a specific blasting operation. 

Also to be noted is the requirement that the operator shall conduct 'periodic' monitoring of airblast. [Section 816.67(b) (2)(i)]. To ensure compliance with the airblast standard, this 

16 
Control of Adverse Effects 

periodic monitoring should at least be on a yearly basis, and 

should monitor airblast from a typical production shot, under 

normal weather conditions for the locality, at the mine perimeter 

or the nearest dwelling, schoo~ or church, etc., as stipulated in 

Section 816.67.(b)(l)(i). 

The limits on page 16 are based on the minimal probability of 

superficial damage to residential type structures, and also take 

into consideration subjective human response. It is appropriate to 

clarify here a coomon cause of confusion and misunderstanding: the 

frequency ranges shown in the table on page 16 refer to the 

response sensitivity of the measuring instrument, and not to the 

predominant frequency of the airblast vibration itself. 

When studying these limitations, it might also be remembered 

that the Bureau of Mines has said that levels exceeding 120 dBL 

will produce some annoyance from rattling and fright, with up to 

10% of homes exhibiting disturbances at 134 dBL (0.1 Hz 

high-pass). Efforts should be made to try to keep airblast levels 

to 110 dBL (2 Hz high-pass) in order to reduce annoyance and 

complaints as much as possible. 

dB LINEAR 

Figure 10. 

Relationship between dB Linear and PSI. 

Airblast is measured in decibels (dB) which are units of 

comparison of sound pressure on a logarithmic scale. It is 

17 
Control of Adverse Effects 

important to understand the significance of a logarithmic scale, which never reaches zero as it goes down, and which increases tenfold for each repeated "cycle" as the scale goes up. It is used 

when a logarithmic scale permits an "exponential" curve to be drawn 

as a simple straight line, and also to conveniently compress a wide 

numerical range scale onto a single sheet of paper. Compared to a 

linear scaling - like feet or pounds, or miles per hour (see Fig. 10 on the preceding page), one can say that a decibel higher up on the scale is larger - sometimes very much larger than a decibel 

lower down the scale. It is not a unit of measurement, therefore, in the same way that a foot or a pound is. Added to this rather complicated concept is the fact that not all decibels are the same 

anytvay: there are certain differences built in called weighting. For example, when decibels are used to measure SOUND (and it has 

already been pointed out that airblast, not being necessarily audible, is not SOUND as such) the "A" weighted decibel scale is used. This is first because SOUND, a steady-state continuous vibration, is not the short duration impulsive event that airblast is. Secondly, because SOUND is generally perceived by human ears, the "A" weighting emphasizes vibrations at those middle frequencies that the human ear is most sensitive to, and puts' less stress on the higher and lower frequencies to which the ear is not sensitive. 

As has already been noted, much air overpressure energy, airblast, is at low frequencies. It is therefore usual to adopt the "Linear" or "Flat" weighted decibel scale for all airblast 

measurements. To avoid further confusion, it must also be explained that dB "Linear" is still a logarithmic scale: dBL are only 1 linear 1 in terms of frequency response. Because of the 

typically low frequency energy in airblast, the OSMRE Regulations (Section 816,67(b)) table of dB limitations on page 16 allow higher decibel readings when the instrument measuring the vibrations is 

more sensitive to lower frequencies. Most modern airblast measuring equipment has a flat frequency response down to 5 Hz, a few instruments down to 1 or 2 Hz, though only a very few laboratory type instruments, which require specific OSMRE approval for use in the field, have a flat response down to 0.1 hz. 

The following table relates some of the more common instruments 

to their frequency response and, therefore, to the appropriate OSMRE airblast limitation. 

INSTRUMt:NT: RESPONSE OSM LIMITATION 

DOWN TO dBL 

VME LOG II 

BERGER 10000 I "' "' '"' "' VME LOG I '"' "' VME SOUNDTECTOR 01 ST·4-D '"' 

2 Hz {optional J "' 

DI ST-4-D 5 Hz (standard) "' 129DI ST-4 '"' 129 DI BT-4-B '"' 129 SINCO S-6 '"' 129 VI BRA-TECH GMS-4 Series 2000 '"' 129 VIBRA-TECH EVERLERT Series 5000 '"' 129 VME Velocity Recorder Model F '"' 129 

18 
Control of Adverse Effects 

The foregoing does not imply that if any instrument with a low 

frequency response is used, a higher and less restrictive airblast 

limitation applies. The magnitude of the airblast will remain the 

same; the lower frequency response instrument may simply read 

higher, dependent on the frequency of the actual air blast. 

One of the reasons why OSMRE requires specific approval for the 

use of very low frequency response instruments is the phenomenon known as "microphonics". Below about 5 Hz, and at sufficiently high overpressures - ov~ 100 dBL or so - it is possible for a 

signal to be induced by low frequency vibrations in the microphone itself, or in its supports, resulting in the recording of falsely high overpressures. The lower the frequency, generally the more 

marked this phenomenon is. Great care should be exercised in 

mounting low frequency response microphones in order to isolate 

them as far as possible fran extraneous vibrations. Rather more 

susceptible are mast mounted microphones and instruments having metal cases. It does not automatically follow, therefore, that the 

lower the frequency response, the more suitable the instrument. 

A more commonly used expression of air overpressure is pounds 

per square inch. PSI can be directly converted to and fran dBL, 

and possesses a great advantage over the confusions of dB in that 

psi is linear, not logarithmic. Direct comparisons are therefore 

possible: i.e., 0.04 psi is twice as high as 0.02 psi. By 

contrast, twice 120 dBL is 126.02 dBL, showing that comparisons of 

this sort should never be made in terms of dB. 

dBL = 20 log P /Po, where P = the air overpressure measured in 

psi, and Po is the reference pressure of 2.9 x 10- 9 (0.0000000029 psi), equivalent to 0.0002 microbars. 

A further linear scale in conmon use, 

with psi, is mb or millibars. The Dallas 

of instrumentation employs the millibar 

airblast. 

and directly equatable 

Instruments (DI) series 

scale for recording 

When predictive calculations are made with airblast data, the 

linear psi scale, or the mb scale, are always used; never dB. 

Conversions can be made to and from the results of such 

calculations. 

The final confusion on dB that should be cleared up concerns 

the last OSMRE airblast limitation that is shown on the Section 

816.67(b) table: "C-weighted-slow response 105 dBC" The 

C-weighted scale is normally used for impulsive noise measurements, 

again specifically in terms of audible noise. This is, therefore, 

an allowable method of airblast measurement, but it is not usual, and as in' the case of instruments with a flat frequency response down to 0.1 Hz, specific OSMRE approval must be obtained for the 

use of C-weighted-slow response instruments. 

19 
Control of Adverse Effects 

FLYROCK 

"Rock that is propelled through the air from a blast. Excessive flyrock may be caused by poor blast design or unexpected zones of weakness in the rock." (Bureau of Mines IC 8925/1983, Appendix 'B', Glossary.) 

Flyrock is the only one of the three main adverse effects where subjective human response is not of concern. No one ever suffers imaginary fljTOck damage. There are few contested flyrock claims: the evidence is usually incontestible except in the case of minor damage to vehicles. 

Explosives are used to fragment rock, and even under normal conditions when there is no intent to displace or "cast" the rock, there can be some unwanted displacement or "throw". Flyrock is simply undesirable and excessive throw. It is a greater problem when deliberate displacement, casting, is an objective. In surface coal operations, equipment damage on site, and property damage outside the permit area, can occur. In contour IllJ.n1ng particularly, flyrock has caused severe personal injury, and even death, and it has also been responsible for major property damage. 

Figure 11. 

Explosive Casting. 

20 
Control of Adverse Effects 

The OSMRE regulations state that flyrock traveling in the air 

or along the grotmd (so flyrock does not have to he "flying") shall 

not be cast from the blasting site: 

1. More than one-half the distance to the 

nearest dwelling or other occupied structure; 

2. Beyond the area of control required tmder Section 

816.66(c); 

3. Beyond the penni t botmdary. 

The OSMRE Regulations are clear and simple, and are based on 

preventing the possibility of any flyrock causing injury anywhere, 

or property damage outside the pennit area or beyond the control 

area. Flyrock being what it is, there is no way that all 

possibility of damage throughout the mine site can be eliminated, 

other than by the removal of all vehicles and equipment beyond possible range ("one-half the distance to the nearest dwelling"). 

OSMRE holds that this is up to the individual mine operator, and 

not a matter for regulation. This is, of course, quite separate from any safety considerations, which are regulated, and which in 

other ways ensure personal safety from the effects of flyrock. 

21 
Control of Adverse Effects 

GROUND IDTION 

"A shaking of the ground caused by the elastic wave emanating 

from a blast. Excessive vibrations cause damage to structures." 

Ground motion is the most frequently cited cause of blast vibration damage, and apart from flyrock, is, in fact, the most 

likely cause of real damage. It is also a very frequent cause of 

imagined damage. 

Ground motion can cause physical damage to mine plant and 

structures, and to neighboring residences outside the mine permit 

area. The most common type of damage associated with excessive ground motion is the aggravation of existing minor cracks. 

The subjective perception of ground motion is probably as serious a problem as the possibility of actual physical damage. When subjected to any significant ground motion, the perceptible shaking of a residence will cause some degree of subjective reaction by the occupants of that building. The extent of this subjective reaction can lead to complaints of damage either real or 

imagined. 

Ground motion will not discriminate, either in terms of cause 

or effect. All structures or facilities surrounding a blast site will respond, with the vibration intensities varying only dependent 

on physical variables such as distance, explosive charge weight per delay, the frequency of the vibration, shot geometry and confinement. Other geological variables may cause significant differences as the site shifts geographically, but at any one 

particular site - and particularly for one specific blast - the three primary variables are as stated as follows: 

• Distance from blasting to position of interest; 

• Explosive charge weight per 8 millisecond delay period; 

• Frequency of vibration. 

These are the fundamental controls, and no single specific site will be more, or less, affected than any other, given the same location. These factors will be discussed in more detail under the 

headings of "Compliance Options" (Chap. 9), "Prediction and Control Methods" (Chap. 10) and "Frequency Considerations" (Chap. 11). 

The OSMRE Regulations (Section 816.67(d)) state: 

(d) Ground vibration. (1) General. 

In all blasting operations, except as otherwise authorized in 

Paragraph (e) of this section, the maximum ground vibration shall 

not exceed the values approved in the blasting plan required under 

22 
Control of Adverse Effects 

Section 780.13 of this chapter. The rnaxinrum gr01md vibration for 

protected structures listed in Paragraph (d)(2)(i) of this section 

shall be established in accordance with either the maximum 

peak-particle-velocity limit of Paragraph (d)(2), the 

scaled-distance equation of Paragraph (d)(3), the blasting-level 

chart of Paragraph (d)(4) of this section, or by the regulatory 

authority under Paragraph (d)(5) of this section. 

All structures in the vicinity of the blasting area, not listed 

in Paragraph (d)(2)(i) of the section, such as water towers, 

pipelines and other utilities, tunnels, dams, impoundments, and 

undergrOI.ttld mines shall be protected from damage by establishment 

of a maximum allowable limit on the ground vibration, submitted by 

the operator in the blasting plan and approved by the regulatory 

authority. 

(2) Maximum peak particle velocity. (i) The maximum ground 

vibration shell not exceed the following limits at the location of 

any dwelling, public building, school, church, or c01!111\.tt1ity or 

institutional building outside the permit area. 

Distance (D) 

frcm the 

blasting site (feet) 

0 to 300 

301 to 5,000 

5, 001 and beyond 

Maximum allowable 

peak particle velocity 

(Vrnax) for ground 

vibration 

(in/sec) 1/ 

1.25 

1.00 

0.75 

Scaled-distance 

factor to be 

applied without 

seismic 

monitoring 2/ 

50 

55 

65 

1/ Ground Vibration shall be measured as the particle velocity. 

Particle velocity shall be recorded in three mutually 

perpendicular directions. The maximum allowable peak particle 

velocity shall apply to each of the three measurements. 

2/ Applicable to the scaled-distance equation of Paragraph (2) 

of this section. 

(ii) A seismograph record shall be provided for each blast. 

(3) Scaled-distance eguation. (i) An operator may use the 

scaled-distance equation, W = (D/Ds) 2 , to determine the allowable 

charge-weight of explosives to be detonated in any 8-rndllisecond 

period, without seismic monitoring; where W = the maximum weight of 

explosives, in pounds; D = the distance, in feet, from the 

blasting site to the. nearest protected structure; and Ds =the 

scaled-distance factor, which may initially be approved by the 

23 
Control of Adverse Effects 

regulatory authority using the values for scaled-distance factor 

listed in Paragraph (d)(2) of this section. 

(ii) The development of a modified scaled-distance factor may be authorized by the regulatory authority on receipt of a written 

request by the operator, supported by seismographic records of 

blasting at the minesite. The modified scaled-distance factor shall be determined such that the particle velocity of the predicted ground vibration will not exceed the prescribed maximum 

allowable peak particle velocity of Paragraph (d)(2) of this 

section at a 95-percent confidence level. 

(4) Blasti~level chart. (i) An operator may use the ground-vibratio~imits found in Figure 1. (OSMRE Regulations) to 

determine the maximum allowable ground vibration • 

... .., 

<I) 

' 

·= • >. 

±: 

... 

..2 2.0 .., 

> 

.., 1.5 

<:) 

~ .. 1.0 

c.. "' 0.9 

.., 

::;;; 

"' 

31: 

0 

<t 

E 

::. 

E 

")( 

::::!: "' 

2 in/sec 

0.75 in/sec 

I 

1 1 

Blast Vibration Frequency, Hz 

Figure 12. (Figure 1. in OSMRE Reg;uations) Alternative Blasting Level Criteria. 

24 

2.0 

1.5 

1.~ 0. 

0.7 

0.6 

0.5 

0.4 

0.3 

0.2 
Control of Adverse Effects 

(ii) If the Figure 1. (OSMRE Regulations) limits are used, seismographic record including both particle-velocity and 

vibration-frequency levels shall be provided for each blast. The 

methods for the analysis of the predominant frequency contained in 

the blasting recordings shall be approved by the regulatory authority before application of this alternative blasting criterion. 

(5) The maximum allowable ground vibration shall be reduced 

beyond the limits provided by this section, if determined necessary to provide damage protection. 

(6) The regulatory authority may require an operator to 

conduct seismic monitoring of any or all blasts and may specify the 

location at which the measurements are taken and the degree of 

detail necessary in the measurement. 

(e) If blasting is conducted in accordance with Paragraph (a) of this section, the maximum ground vibration and airblast 

standards of Paragraphs (b) and (d) of this section shall not apply at the following locations: 

(1) At structures owned by the permittee and not leased to 

another person; and 

(2) At structures owned by the permittee and leased to another 

person, if a written waiver by the lessee is submitted to the 

regulatory authority before blasting. 

These ground vibration regulations are the most complete and 

complicated of all OSMRE regulations pertaining to blasting. What 

is not always realized is that they offer the mine operator the 

option of complying with the ground motion regulations in four 

different ways, while protecting structures in the area from damage 

due to excessive vibration: 

• Distance related maximum peak particle velocity; 

assumes that the vibration frequency content decays with distance: no vibration frequency determination 

required. 

• Distance related minimum scaled distance: no vibration 

measurement or vibration frequency determination 

required. Not site specific. 

• Modified scaled distance. Site specific, based on 

regression analysis. 

• Blasting level chart: this can only be done if both 

peak particle velocities and frequencies are measured, but this method: 

(a) Permits the most accurate prediction of effects. 

25 
Control of Adverse Effects 

(b) Provides the best defense in the event 

of litigation. 

(c) Offers the minimum restrictions on blasting 

procedures and, therefore, the optimum potential efficiency and cost savings. 

Ground motion is normally measured in terms of peak particle velocity, expressed as inches per second. Inches per second 

represent a linear scale and, therefore, comparisons can be made: 

2.0 inches per second is double 1.0 inch per second. 

As the vibrations from a blast arrive at a predetermined point, 

a particle of soil or rock at that point will vibrate, or move 

randomly in all directions for a short period of time. That is why 

it is customary to refer to peak PARTICLE velocity, and that is 

also why such vibrations are measured in three mutually perpendicular planes; to represent, as far as possible, three 

dimensional vibration. 

The base unit for this measurement is velocity. It is the 

highest velocity that the particle achieves during the course of 

the event, and can be expressed in inches per second, occurring in 

each of the three planes, or simply as the highest velocity that 

occurs in any of them. 

The OSMRE regulations (Note 1/ to Section 816.67(d)(2)) require that measurement shall be made in each of the three planes, but 

that the maximum allowable velocity limits, applicable to each of 

those planes, can be any one of them. It is not necessary to 

develop vector sum (resultant) velocity calculations. 

The planes of motion referred to above are normally considered 

to be: 

1. LONGITUDINAL: (Sometimes called RADIAL) Measured 

in a direct line horizontally towards the blast from 

the point of interest or measurement. 

2. TRANSVERSE: Measured horizontally at 90 degrees to 

the longitudinal plane. 

3. VERTICAL: Measured vertically at 90 degrees, therefore, to both the longitudinal and the 

transverse planes. 

These regulations, in that they offer the operator four options in terms of compliance, allow great freedom. When distances and 

charge weights do not make for critical conditions, then the 

operator is free to choose the least onerous method - probably simply to adhere to the scaled distance rule. When conditions 

approach the critical, then the operator could well choose to 

26 
Control of Adverse Effects 

employ the Figure 1 'Alternative Blasting Level Criteria' (Fig. 12, 

page 24 in this Manual) • At first sight, these may appear to be 

the most restrictive and complicated, but in fact may well offer 

the operator the least cumberscme and most efficient answer. This 

will be discussed in greater detail later in the manual. 

FACl'ORS WHICH CAN INFLUENCE BLASTING VIBRATIONS 

Variable factors which can have varying degrees of effect on 

ground vibration and air blast, both within the control of 

operators and outside their control, are summarized in Table 1, 

below, and in Table 2, overleaf, modified fran pages 25 and 26 in 

"Control of Vibration and Blast Noise fran Surface Coal Mining", 

Volume 1, (Wiss, Janney, Elstner and Associates). 

GROUND VIBRATION CONTROL 

variables "ithin the control Influence on ground motion 

of mine operators 

Signif. Moderately Insignif. 

signif. 

1. Charge weight per delay X 

2. Delay interval X 

3. Burden and spacing X 

4. Stenvning (amount) X 

5. Stemming (type) X 

6. Charge length and diameter X 

7. Angle of borehole X 

8. Direction of initiation X 

9. Charge weight per blast X 

10. Charge depth X 

11. Bare vs. covered primacord X 

12. Charge confinement X 

Variables not in control of 

mine operators 

1. General surface terrain X 

2. Type and depth of overburden X 

3. Wind and weather conditions X 

Table 1. 

Factors which influence ground motion. 

27 
Control of Adverse Effects 

AIRBLAST CONTROL 

Variables within the control Influence on overpressure of mine operators 

Signif. Moderately lnsignif. signif. 

1. Charge weight per delay X 

2. De 1 ay i nterva 1 X 

3. Burden and spacing X 

4. Stemming (amount) X 

5. Stemming (type) X 

6. Charge length and diameter X 

7. Angle of borehole X 

B. Direction of initiation X 

9. Charge weight per blast X 

10. Charge depth X 

11. Bare vs. covered primacord X 

12. Charge confinement X 

Variables not in control of 

mine operators 

1. General surface terrain X 

2. Type and depth of overburden X 

3. Wind and weather conditions X 

Table 2. 

Factors which influence airblast. 

28 
CHAPTER 4 

DAMAGE 

All of the three main adverse effects of blasting can cause 

dalllage. However, when the word "damage" is used in the context of 

blasting effects, the assumption is often made that the blasting in 

consideration was the direct cause of the damage in consideration. 

Because of this, it is necessary first to carefully distinguish between the words "damage" and "defect", and then to define just what is meant by blast vibration damage. All houses have defects. 

DEFINITION OF DAMAGE 

The Bureau of Mines Report of Investigations, RI 8507, 1980, defines damage due to blast produced ground vibration thus: 

"Threshold damage was defined as the occurrence of 

cosmetic damage; that is, the most superficial interior cracking of 

the type that develops in all homes independent of blasting. HOmes 

with plastered interior walls are more susceptible to blast 

produced cracking than modem gypSI.DD wallboard • • " 

The Bureau's Bulletin 656 (1971) mentions the following indices 

of damage: 

1. Major damage (fall of plaster, serious cracking). 

2. Minor damage (fine plaster cracks, opening of 

old cracks). 

3. No damage. 

The line that separates real from alleged or imaginary damage is ill-defined. It is therefore very CO!IIliOn to talk in terms only of the "probability" or "possibility" of damage. "Damage" itself 

is a word that can describe anything from a hairline cosmetic crack 

to a catastrophic structural collapse. 

In the context of this Manual, therefore, it nrust be recognized that except when otherwise defined, all damage references mean 

minor cosmetic defects: the appeara~ce of small hairline cracks; the lengthening or widening of existing small cracks; paint or 

plaster flaking or peeling; and, in the case of airblast, simple window glass breakage. 

"Probabilities" or "Possibilities" of damage also need careful 

consideration in order that these terms convey a realistic meaning. RI 8507 (p.49) states: "Analysis of damage probabilities is 

29 
Damage 

particularly difficult because of the low probabilities being 

sought. For example, reliable determination of the 2% damage 

probability theoretically requires 49 non-damage measurements for 

every one of damage. " 

AIRBLAST DAMAGE 

There is general agreement among blast vibration experts, 

govermnental regulatory and consultants, that the first damage 

effects due to airblast take the form of broken window glass. 

Large, plate-glass windows and shop fronts, etc., are more prone to 

damage than small glass window panes. Badly set, pre-stressed, or 

loose panes are more prone to fracture than well set, firm panes 

that have no stress raisers such as impinging glazier's brads, 

etc. Structural damage such as plaster cracking due to airblast is 

not only very rare, but is always acc0!11pllnied by window brea.~ge. 

Airblast frequently causes concern, annoyance, and of course, 

complaints. Virtually all of the data relating to extensive 

structural damage due to airblast is derived either from records of 

nuclear events, or fr~ such calamitous accidents as the Texas City 

disaster, when an entire cargo of BllJDonium nitrate on a freighter 

in the docks detonated in the course of a fire aboard the ship. 

Minor cosmetic damage, cracking etc., might occur in 

conjunction with extensive window glass breakage. Past research 

has shown that occasional damage to plate glass, which is more 

damage sensitive than plaster, can occur at approximately 141 dBL 

(0.0325 psi). Normal size window pane breakage can occasionally 

occur at perhaps 151 dBL (0.1029 psi) or slightly over. 

Annoyance from blasting, which is completely subjective, has no 

adequate study to assign numbers to. If annoyance from sonic boom 

produced rattles is considered, it could be said that if airblast 

can be kept at or below 120 dBL (0.0029 psi) then annoyance will be 

minimal. 

Imagined damage from airblast, ·because of the highly 

perceptible nature of this effect, is extremely common. 

FLYROCK DAMAGE 

Is obvious. As has already been discussed, flyrock does not 

generally become the subject for argument. It is the one 

blast-generated cauae where minor, cosmetic damage is not in 

consideration. The COIII!IOn evidence for flyrock damage is a hole in 

the roof, and a rock on the floor. "Probabilities", or degrees of 

30 
Damage 

damage, are not of concern: if flyrock of any significant size 

contacts a structure, it causes serious localized damage. 

Flyrock can cause serious damage, accompanied by obvious 

consequential problems, to overhead wires: mainly electricity 

supply, but also to telephone COI1Illlll1ications. It can also be of 

concern near microwave antenna installations, repeater stations, 

and other communication and broadcasting antennas. 

"Imaginary" flyrock damage does not occur in the way that 

imaginary damage is attributed to ground motion or air 

overpressure. In the case of windshield glass breakage - or hail 

damage - to vehicles, however, it might be more difficult to 

differentiate causes. This is one reason why vehicle traffic should 

be closely controlled within the permit area, . and why flyrock 

should be closely controlled- i.e. prevented- outside' it. 

The rost serious effect of flyrock, quite apart from any 

possible damage consideration, is of course the fact that, alone 

among the adverse effects of blasting, flyrock can cause not only 

serious injury, but death. Ground vibration does not threaten life 

or limb in this way, nor, under any normal circumstances, does 

airblast. · Flyrock does, and this possibility nrust always be borne 

in mind. It is the one ultimate adverse effect of blasting that 

the surface mine operator nrust never be guilty of. 

GROUND IDTION DAMAGE 

Apart from flyrock, this is the most conmon form of damage due 

to the three adverse effects of blasting. It is also the most 

easily and consistently controlled. 

Ground motion blast vibration damage is well documented, and 

points at which threshold damage can occur are the best defined of 

the three effects. 

Failure can occur to brittle materials such as plaster at 

particle velocities less than 1 inch per second at ~ery low 

frequencies. The majority of failures will not begin to occur, 

however, until vibration levels exceed 3 to 4 inches per second. 

The table on the next page, derived from Table A-2, Appendix 1 A 1 to RI 8507, shows an interesting comparison between the 

vibration levels at which various degrees of damage may occur, and 

the type of terrain or rock on which a structure is built. It is 

based on the work of U. Langefors and B.K. Kihlstrom: 

31 
Damage 

PEAK PARTICLE VELOClTY:INS/SEC. 

DAMAGE EFFECTS: SAND, GRAVEL, CLAY MORAINE, SLATE OR GRANITE, HARD LIMEBELOW WATER LEVEf; SOFT LIMESTONE; STONE OR DIABASE; 

c"'3000-5000'/sec c~6000-10000'/secl c=15000-20000 '/sec 1 

NO NOTICEABLE 0.71 1.4 2.8 

CRACK FORMATION 

FINE CRACKS AND 1.2 2.2 4. 3 

FALLING PLASTER 

THRESHOLD 

CRACK FORMATION 1.6 3.2 6.3 

SEVERE CRACKS 2 .4 4. 5 9.1 

lpropagation velocity in ~edia is given by c. 

It is clear, therefore, that the possibility of actual 

threshold damage is dependent not only on the peak particle 

velocity, but also on the frequency content of that vibration, and 

on the type of terrain or rock upon which the structure stands. It 

is also dependent on the type of structure, the height of the 

structure; the natural frequency of the structure, and of course, 

on the state of repair - or disrepair - of the structure. Even 

when that structure can be said to be in a good state of repair, it 

might also be that it is old, or that it has some particular 

historic significance. Factors such as this dictate special 

considerations, perhaps specific velocity limitations. 

It is also clear that some of these conditions may combine so 

that even if actual damage is unlikely below 2 or 3 inches per 

second, it is nevertheless POSSIBLE that threshold damage might 

occur under some conditions at velocities as low as 0.5 to 0.7 

inches per second. Notwithstanding the great volume of opinion and 

evidence showing that relatively high vibration levels are 

necessary to cause damage, it is also quite clear that the OSMRE 

regulations impose very realistic limitations. Recalling the 

intent of the Act, the reg~uations provide positive protection 

against damage to private and public property. 

A frequently heard argument from complainants is based on the 

belief that if a single event may not damage the structure, then 

multiple events must have a cumulative effect. They therefore base 

their damage claim not on the effects of isolated events, but on 

the effects of repeated blasting. 

The Bureau of Mines recent Report of Investigations, RI 8896, 

1984, deals precisely with this conmon misapprehension. A test 

house was built in the path of an advancing surface coal operation 

so that it could be thoroughly studied in terms of repeated 

blasting effects. Structural fatigue and damage were studied over 

a two year period, during which time the house was subjected to 587 

production blasts, the peak particle velocities ranging from 0.10 

to 6.94 inches per second. Following this blasting effect study, 

the entire house was shaken mechanically to produce fatigue 

cracking. 

32 
Damage 

Cosmetic or hairline cracks 0.01 to 0.10 rnm wide appeared 

during construction of the house, and also during a period when no 

blasting was taking place. The formation of cosmetic cracks 

increased from 0.3 to 1.0 cracks per week when ground motions 

exceeded 1.0 inch per second. Human activity and changes in 

temperature were equivalent to those produced by ground motions up 

to 1.2 inches per second. 

When the entire house was shaken mechanically, the first cracks 

appeared after 56,000 cycles, the equivalent of 28 years of blast 

generated ground motions of 0.5 inches per second, twice a day. 

If blasting occurred only once a day, this would be equivalent 

to a period of 56 years; if blasting was only once a week, then it 

would equate to blasting for a period of 392 years! 

Induced strain Ground vibration equivalency, Activity Locationl ("in/in) or ( i n/s) 

structure 

motion (in/ s) Envelope2 Regression 1 i ne3 

Wa 1 king •••.•.• A4, low corner, 0.16 i n/s .•... 0.07 0.29 south wall. 

A4, low corner, 0.039 i n/s .... .005 .07 east wall. 

52 •...•..•.•.. 9.1 1.1i n/i n .... .03 .09 Heel drop ..... A4, low corner, 0.14 in/s .... .06 .24 south wall. 

A2, mi dwall ••. 0.65 i n/s ..... .06 • 17 52 .•••..•••.•. 20 JJi n/i n ..... .03 .20 Low jump •.•.•. A4, low corner, 0.12 i n/s ..... . 05 .18 south wall. 

A2, midwall ... 1.8 i n/s ••.•.. .26 .92 High jump ..... A4, low corner, 0.31 i n/s ..... .29 . 74 

south wall. 

A2, midwall. .. 1.2 i n/s ...... .15 .52 

52 ...•....•.. 42 lJ in/in ..... .28 .62 Entrance door A4, low corner, 0.18 i n/s ..... .09 .22 s 1 am. east wa 11. 

A3, midwall ... 1.3 i n/s ...... .13 ."52 

58 ..•.•..•.•.. 21 IJ in/in ..... .27 .60 51 i ding glass A1, high corner, .87 i n/s .... .. . 51 .90 door slam. east wa 1 1. 

51. ....•...... 48.8 JJ in/in ... .so 1.40 Sinking na i 1 s A4, low corner, 0. 51 i n/s ..... .38 .80 for pictures east wall. 

AS, low corner, 0.67 i n/s ..... .59 .89 west wa 11. 

A2, mi dwa 11 ... 3.9 i n/s ...... .92 2.16 

51 ..•....•.•.. 21 IJ in/in ..... .18 • 41 58 ..••...•.•.. 32 1-1in/in ...•. .38 .87 

512 ..•.•..•..• 88.7 lJ in/in ... .88 1.44 

1From figure 13. 2

Based on envelope of strain or structure motion versus ground vibration 

data. 3

Based on regression line through strain or structure motion versus ground vibration data. 

Table 3 

Human activities and equivalent ground vibration levels. 

33 
Damage 

Table 3 on the previous page, based on Table 9, page 35 in RI 

8896, shows ground motion equivalencies for common human activities 

in the test structure -- activities that are repeated many times 

daily in the normal occupancy of a residential structure. 

Human subjective tolerance to vibration levels is such, 

however, that levels of 0.5 inches per second annoy 5% of the 

population, so constant attention must be paid to this problem. 

Careful consideration should always be given to this important 

subject, which is dealt with in the following chapter. Efforts 

made in this direction pay dividends, and will not be regretted. 

34 
CHAPTER 5 

HUMAN SUBJECTIVE TOLERANCE 

It has already been stated that this problem does not occur in 

terms of flyrock. It does occur, extensively, both in terms of 

airblast and ground motion, although the humans who are suffering from the subjective reaction to these effects are frequently unable 

to differentiate between them. 

One of the first things to recognize is that when blasting operations take place, there is no way by which complaints can be totally eliminated. At any location where the ground motion or air 

overpressure is perceptible to human beings, there exists a possibility of complaint. 

Factors that can affect human subjectivity are: 

• The event itself: human perceptibility. 

• The frequency (number of events per day or week). 

• The time of day. 

• The structural response itself. 

• The structural condition of the property. 

• The degree of activity of the subject. 

• The state of health of the subject. 

• The state of mind of the subject. 

• The position and attitude of the subject: i.e. in bed, 

prone; on a floor center, sitting, etc. 

• The local perception of the operation. 

• The history of local damage claim payments. 

• The history of "good neighbor" payments or assistance, related to damage claims where liability was denied. 

Additional to the above factors, which all respond to genuine subjective human reaction, is the underlying possibility that human cupidity nrust be considered. Particularly when a structure has suffered deterioration that could be costly for the owner to 

correct, allegations of blast vibration damage are frP~ently made. Interrogation by experienced personnel will often leave such 

a complainant completely unshaken in his apparent conviction that 

35 
Human Subjective Tolerance 

the blasting activity was the cause of his misfortune. Such cases, 

even when the technical evidence is overwhelmingly clear that blast 

damage could not have occurred, can be a persistent problem. Good 

adherence to OSMRE regulations, complete blasting records, and 

above all specific blast vibration measurement records will stand 

the conscientious operator in good stead in such situations. 

Whereas the OSMRE regulations do not specifically address these 

problems of human subjectivity, they do in fact provide a 

considerable measure of protection against them. The most 

effective protection is provided by those options that include 

actual vibration level monitoring and recording. At great 

distances, of course, these problems are unlikely to arise, and the 

scaled distance rules may usually be adopted. Bearing in mind, however, that complaints cannot be totally eliminated, it is 

perhaps timely to note that blast vibration complainants have 

threatened litigation when scaled distances have been in excess of 

200, and instrumentation has been scarcely able to record the 

effects. One case is known when the scaled distance was in excess 

of 1000! 

Figure 13. 

Good Public Relations efforts assist subjective problems. 

36 
Human Subjective Tolerance 

At what level are human beings able to perceive blast vibration effects? Airblast is extremely difficult to define in this 1\fay, because of the very variable audibility of any particular event. If the predominant frequency of the event is low, it could be that, 

say, 115 dBL might be unnoticeable, whereas if the predominant frequencies were well into the range of human hearing, this same event might be quite annoying. It is also possible that where the airblast frequencies match the natural frequencies of structures, 

secondary vibrations producing rattling, etc., can occur. This effect can not only increase the subjective perception of an event, but can also extend its apparent duration. Ground motion, on the other hand, while frequency dependent to a point, depends much on the sensitivity of the human subject. Most authorities agree that the threshold of human perception for blast vibration ground motion is around 0.03 inches per second. Depending on activity, sensitivity, and whether or not the subject knows when the event is 

to occur, a few humans can sense ground motion as low or lower than most instruments are able to: about 0.01 inch per second! 

Although complaints can occur at any level perceptible to humans, they are 1musual below 0.08 inches per second or so. As 

peak particle velocities increase and as local and individual sensitivities increase, so will the number of complaints. At, say, 0.25 inches per second, a level that is eminently safe, and well within OSMRE limits, except below 2Hz, complaints can be expected. 

37 
CHAPrER 6 

CAUSES OF EXCESSIVE ADVERSE EFFECTS 

Apart from the control methods that are discussed in Chapter 10 of this manual, consideration of some of the basic causes of 

excessive adverse effects will permit simple practical controls that will minimize these problems at the outset. 

be: 

AIRBLAST 

The four primary causes of airblast are generally recognized to 

• The Air Pressure Pulse: 

displacement at the free 

borehole collar. 

• The Rock Pressure Pulse: 

caused by direct rock 

face or mounding at the 

caused by vibrating ground. 

• The Gas Release Pulse: caused by gas escaping from the 

detonation through fissures in the fractured rock. 

• The Stermrlng Release Pulse: caused by gas escaping from 

blown-out stermrlng. 

A further cause that can lead particularly to more highly audible airblast is the presence of uncovered detonating cord on 

the surface of the shot. 

Terrain - normally outside the control of the blaster except perhaps to a very limited extent - will also have an effect on 

airblast. Terrain can have a mitigating effect when it acts as a 

barrier, but also, when it takes the form of a reflecting surface, it can materially increase the effects. 

Weather - again normally outside the control of the blaster - has also a very marked effect. Atmospheric variables alone account for the great difficulty of predicting airblast effects by means of regression analysis, a technique that is highly effective when 

applied to ground motion. Figures 14 - 17 overleaf illustrate the highly variable effects of weather conditions: these show inversion effects alone, without considering the additional and considerable effects of wind direction and velocity. Couple those variables 

with the effects of terrain and it can be readily understood why 

air overpressure is most difficult to predict with any degree of 

consistency: any exercise of this sort should be undertaken only with great caution. This is not to say it cannot be done, but the 

39 
Excessive Adverse Effects 

limitations of such predictions should be fully understood, and the 

conditions carefully specified. 

I + Blut Site 

Figure 14. 

SOUND SPEED BLAST SITE 

Dlereulng lound apeec~ Vtrtcll pllne lhowlng 

& ~ralln witt -.ct. lound propqlllon 

Figure 16. 

HorlzorUI PIIM ahowlng I04.IIId ,....... z-a or loUd :,:c-mwrelat~Mtr 

louncl ,..... - ....... 

ray1 1 .1t.!: 

' ' ' SOUND SPEED BLAST SITE 

SO&I'Id ~ad (C) & 

Tarnpen~u. m 

Figure 15. 

Figure 17. 

(Figures 14 to 17 courtesy of E.I. duPont de Nemours & Co.) 

If airblast effects can present problems, then because of 

unfavorable atmospheric variables, blasting should be avoided, when 

possible, during the following conditions: 

• During a temperature inversion, indicated by hazy, 

low visibility days with little or no wind. 

• During the strong winds that accompany the passage of a cold front. 

• When the surface temperature is falling. 

• Early in the morning, or after -sunset, on clear days with light winds. 

40 
Excessive Adverse Effects 

• On overcast days with a low ceiling, particularly 

during calm conditions. 

At all 

importance, 

design to: 

times, when the control of airblast becomes of 

particular attention must be paid during the blast 

• Covering up all exposed detonating cord with at least 

a foot thickness of spoil. Heavier detonating cord 

will require deeper burial. 

• Proper stemming to an adequate depth. Drilling cuttings 

are not a good stemming material, nor is the sometimes rec~ended damp sand. The best stemming material is 

coarse (1/4" to 3/8") dry, sharp gravel. 

• Proper burden and spacing. 

• Mud seams, voids, etc., should be noted, and proper 

precautions taken such as decking or stemming through. 

• Re-orienting any high free face away from populated 

areas, if possible. 

• Proper choice of delays. 

• Atmospheric variables, as discussed above: avoid 

blasting whenever winds are blowing from the blast 

site towards populated areas. 

• Time of shots: if possible, shots should be fired 

during periods of high human activity. The noon hour, 

or after school is out are typically suitable times. 

Avoid blasting during quiet periods, say, when senior 

citizens have retired for an afternoon siesta. 

Figure 18. 

Proper stemming effectively reduces airblast. 

41 
Excessive Adverse Effects 

Attention to the above points - which are virtually the only 

ones the blaster has any control over anyway - will minimize 

problems due to airblast. To a great extent the stemming release 

pulse can be controlled, as can, to a rather lesser degree, the gas 

release pulse. Apart from terrain and weather variables, this only 

leaves the dominant effects of the air pressure pulse, and to a 

lesser extent, the rock pressure pulse. Since these both tend to 

be at lower and less audible frequencies, the overall impact of 

airblast will be greatly reduced. 

FLYROCK 

Flyrock occurs when the blast is improperly designed or 

loaded. Incorrect burden for the explosive load and the geology 

assures a flyrock problem. A burden too small for the drill hole 

size and rock type could result in fly from the face. In the same 

manner, excessive burden or rows of holes without relief will 

result in violence in the collar zone. Loading holes through zones 

of wealmess, or into voids, will result in "blow outs". Flyrock can 

also be caused, or contributed to, by geological conditions which 

can not always be detected prior to the shot. 

One technique that is receiving particular attention these days 

is "casting". This is, as has already been stated, the deliberate 

use of explosives not merely to fragment the rock, but to move 

overburden to a spoil pile without, or with minimal rehandling. 

The mine ls trying to control and direct the throw of material so 

that as much · as 65% of the overburden is displaced to the spoil 

pile. By the controlled application of some of the causes of 

flyrock, the mine can move large volumes of material. Poor 

application of casting techniques will result in adverse effects, 

with flyrock being the greatest, closely followed by excessive 

air blast. 

The main control that can be applied to the blast design is to 

ensure proper burden and stemming, together with loading the 

explosives into the borehole to place the energy release at the 

points where it is required to break the rock. Generally, it is 

considered that a burden dimension less than 25 times the diameter 

of the explosive charge can result in long flyrock distances, while 

excessively large burdens can cause violence in the collar zone 

(Bu. Mines IC 8925, p.77). Where blasting must truce place, and it 

is difficult to ensure proper burden and stemming relationships, 

then blasting mats or spoil cover must be used to control flyrock. 

The above considerations together form the best control solutions 

to the flyrock problem. 

Flyrock and airblast are closely related, and proper techniques 

to control flyrock will greatly assist in reducing airblast 

42 
Excessive Adverse Effects 

problems. By knowledgeable placement of relationship to the face, the collar, and to weakness, flyrock can be effectively controlled. 

GROUND IDTION 

the explosive in 

the known zones of 

Excessive ground motion is caused by improperly designed blasts, excessive - or insufficient - explosive charge weights, excessive confinement and too short time periods between successive delays. 

The fundamental control available to blasters has for years been based on the simple relationship between charge w·eight and distance. Reducing the charge weight, or increasing the distance, or both, results in a smaller ground vibration. Since confinement and breakage also have a very considerable effect, the above is an oversimplification, but if it is also stated that excessive ground motion equates to wasted energy, it is easier to visualize the following: 

A properly designed blast will give lower ground motion 

per pound of explosive than one that is poorly designed. For a given weight of explosive that is detonated, a certain fixed amount of energy is released. If that energy is used in breaking rock into fragments, there is less "waste energy" available at the end of the reaction to go into the grrnxnd as excess vibration. A badly designed shot, where good breakage is not obtained, will generally produce higher levels of grrnxnd motion. This fact must also be remembered when specifically high confinement shots are being designed (e.g. pre-splitting) because in these cases any "site-specific" attenuation formula that has been developed may not apply. In fact, when developing such attenuation formulas for any particular mine site, it is normally necessary to divide data into 

groups: "OVERBURDEN", "COAL" and "OVERBURDEN PRE-SPLIT", etc. Separate formulas would have to be developed for each category. This subject will be discussed fully in Chapters 9 and 10. 

The U.S. Bureau of Mines, in IC 8925, outlines the following five techniques that can be used to Qinimize ground motion: 

1. Reduce the charge weight of explosives per delay period. This is most easily done by reducing the number of blastholes fired 

on each delay. If there are not enough delay periods available, a sequential timer blasting machine can be used, or a combination of surface and in-hole nonelectric delays. The manufacturer should be consulted for advice when using the sequential timer or compl~~ delay systems. If the blast already employs only one blasthole per delay, smaller diameter blastholes, a lower bench heip-)1t, or several delayed decks in each blasthole can be used. Delays are often required when presplitting. 

43 
Excessive Adverse Effects 

2. Overly confined charges such as those having too much 

burden or too much subdrilling should be avoided. The primer should not be placed in the subdrilling. Where it appears that a 

later row of blastholes will not have adequate relief, a delay 

period should be skipped between rows. 

3. The length of delay between charges can be increased. This 

is especially helpful when firing large charge weights per delay at 

large blast-to-structure distances. However, this will increase 

the duration of the blast, and may cause more adverse reactions 

frcxn neighbors. 

4. If delays in a row are arranged in sequence, the lowest 

delay should be placed in the hole nearest the structure of 

concern, except at very short distances when other considerations 

apply. In other words, the shot should normally be propagated in 

a direction away from the structure. 

5. The public's perception of ground vibrations can be reduced 

by blasting during periods of high local activity, such as the noon 

hour, or shortly after school has been dismissed. Blasting during typically quiet periods should be avoided, if possible. 

Very recent research ("Geologic Factors Affecting Vibration 

from Surface Mine Blasting", USBM 1985, See Bibliography) has shown 

that it is possible to reduce ground vibration levels, particularly low frequency vibrations, by the proper selection of delay periods. Firing times are chosen by analyzing the vibration 

response created by the detonation of a single blasthole. This 

response is a function of the geology at the blast site, the 

vibration travel path, and the geology at the recording location. 

Blast firing times can be selected to create "out of phase" vibrations with adjacent holes. Significant reduction of vibration 

levels (up to 50%) have been achieved in controlled tests. 

Tables 1 and 2, pages 27 and 28 in Chapter 3, summarize the 

factors which influence ground motion and airblast to one extent or 

another. The influence might be to increase or decrease the effect 

of the vibration, as in the case of confinement. Highly confined 

blasts will tend to produce high ground vibrations and low 

airblast. Unconfined blasts will cause low levels of ground motion, 

but very high overpressures, with high frequencies, audible over 

long distances. 

44 
CHAPTER 7 

VIBRATION IDNITORING 

The Bureau of Mines Reports of Investigati.ons, RI 8506 and 8507 

are the current standards for defining methods of monitoring ground 

motion and airblast respectively. There are many different 

monitoring instruments available; some used more in a research 

capacity, and others used basically for compliance and effect 

control. In this chapter, and in the later chapter devoted to 

instrumentation, focus will be upon the specialized instruments 

produced specifically for blast vibration compliance and control. 

The majority of these instruments are portable. 

AIRBLAST MONITORING 

The basi.c choices open to the operator are: 

• Peak only vs. entire time history recording instruments. 

• Permanently or semi-permanently installed vs. portable, 

operator set-up and/or attended. 

• Monitoring by consultants. 

Any instrument with a frequency response listed within the 

requirements of Section 816.67(b) can be used, and because the 

OSMRE regulations regarding airblast do not relate to the 

predominant frequency of the airblast itself, peak reading instruments alone are satisfactory for compliance. In instruments 

which also record ground motion, the airblast may be reported simply as a peak instead of a full waveform. It may be, however, 

that instruments that record the entire time history waveform would 

be considered to be preferable, since: 

• A waveform of the entire event can frequently help 

to identify causes of excessive airblast. 

• A waveform, by its "signature", can permit 

discrimination between blast and non-blast overpressure 

events. This can be of particular importance where 

remotely installed "constant-recording" instruments 

are concerned. 

Permanently installed "constant-recording" instruments can be 

more convenient than portable operator attended or set-up 

instruments. They do not require the labor expense of an 

operator. They will record any event of a recordable magnitude 

(generally over about 100 dBL) if they are of the peak·recording 

45 
Vibration Monitoring 

type, and any event over a preset trigger threshold level if they 

are of the acoustic/seismic triggered variety. This is an 

advantage in favor of the peak recording instruments, and a slight 

disadvantage of the automatically triggered instrument - certainly 

if it is considered desirable that every event, no matter how minor 

it might be, should be put on r~cord. 

This last disadvantage of triggered instl<]ffients may not be 

immediately apparent. However, if it is remembered that complaints 

can and will arise from any humanly perceptible blasting event, and 

that in such circumstances (for the unit failed to receive the 

minimum vibration th?t would have been necessary to trigger it) the 

total lack of a record may prove difficult to explain to an 

attorney. A flat trace, supported by testimony that the instrument 

was operating at the time of the blast, is at least a record, 

albeit of non-measurable vibration. This can be of real value when 

a complaint situation is at issue. 

Figure 19. 

Field Monitoring. 

Portable operator-attended instruments require someone to set 

them up at a specific location, and to retrieve them following the 

blasting event. They do not necessarily require critical timing, 

nor do they always require the operator to be physically present 

46 
Vibration ~lonitoring 

during the actual shot, particularly the magnetic tape recording instrument which will run unattended for up to a half hour or so. 

Some of these portable instruments can also be of the seismically 

or acoustically triggered variety, though at closer distances, 

missing a shot due to non-triggering is normally less of a 

problem. Nevertheless, care has to be exercised to ensure that the 

trigger threshold level is set appropriately: net so high that 

there is a risk of missing an event, and not so low that passing traffic, etc., might cause spurious events to be recorded. 

The portable instruments tend to be more versatile, and offer 

more practical uses than the remotely installed instruments, since 

they can be moved to any location, and can collect both high and 

low level data. This is of lesser importance when monitoring airblast, because of the difficulty in applying predictive techniques to airblast data. For airblast monitoring, portable instruments can be moved to any position inside or at the the 

perimeter of the permit area, and to any outside point of concern 

or complaint site. 

All instruments used for airblast monitoring should be equipped with windscreens over the microphones, which should be placed in an 

area not masked by trees or buildings, at least 5 ft. to the side 

of any structure, and 3 ft. to 5 ft. above the ground. 

When monitoring both ground motion and airblast at a structure, it is desirable to employ an instrument that records the ground motion and airblast as full waveform time histories. In case of 

excessive adverse impacts, or persistent complaints, the airblast 

and ground motion time histories may then be compared in order to 

identify the major cause of any problem. At boundary limits, for 

compliance monitoring [Section 816.67(b)(2)] or for verification, a 

peak reading airblast monitor is adequate. 

When employing consultants to carry out airblast monitoring 

programs, be particularly careful that the consultant is, in fact, 

a specialist in blasting vibrations. It might seem that this 

caution is unnecessary, however one proposed local airblast 

ordinance was recently based on the study of a professional engineer who was not only apparently unaware of the differences 

between 1 sound 1 and 1 airblast 1 , but did not seem to fully understand the difference between a steady state and an impulsive 

event. He attempted to use the noise study parameters such as dBA, 

Leq, and d 1 , and also based his conclusions on measurements made of 

only two events at a single location in mountainous terrain! 

Should any prospective consultant prepare to monitor a shot, 

displaying any of the above tendencies, or using a "sound level 

decibel meter", it should be taken as an inmediate warning that he 

is not sufficiently experienced or competent in blast vibration 

monitoring and control. Be very careful when selecting a consultant. 

47 
Vibration Monitoring 

GROUND mTION mNITORING 

1-lhenever ground motion needs to be recorded for whatever 

reason, by the mine operator, independent consultant or regulatory authority, the actual placement of the instrumentation is the primary consideration. Adequate time should be allowed for the 

proper set-up of the instrumentation at the chosen location, before 

the detonation of the blast. Hurried instrument set-up can lead to 

imperfect orientation and sensor-to-ground coupling, and will often 

result in less than adequate results. 

Figure 20. 

Monitoring ground motion and air blast. 

The first consideration in terms of instrument placement is the 

actual location of the ground motion sensor, or transducers. This 

placement has to be decided both in terms of distance from the 

blast site, and, at a structure, in terms of the transducer 

placement relative to the structure. 

Distance from the blast is not always a matter of choice. If 

it is necessary to monitor ground motion at the particular structure then obviously distance from the blast is dictated cy the 

distance that structure is from the blast. If this limitation does 

not apply, then it is essential to remember that the most useful 

data will be collected at as widely different scaled distances as 

possible. The distance to the blast decision, if open, will be 

48 
Vibration Monieoring 

dependent upon recent monitoring history: if large scaled distance 

data is already available, then the aim should be to collect data 

at small scaled distances. Attempt, as far as possible, to collect 

data at as low a scaled distance as is safe and prudent, and at as 

high a scaled distance as is measurable. In between these 

extremes, it is desirable to have as even a distribution of data as 

possible. IVhenever the choice of distance is open to the operator, 

the temptation to set-up the instrument in the same, easy, 

convenient spot where it was last time must be avoided. Vary the 

data, and the extra effort will be found to be well worth while 

when the need to predict vibration arises, as sooner or later it 

surely will. 

The second consideration in terms of instrument location 

concerns the local placement of the transducers with reference to 

the structure itself, and the actual connection of the transducer 

head to the ground, or "coupling". 

Figure 21. 

Instrument placement. 

The placement of the transducer head should be outside any 

building or structure of concern, since the vibration limits are 

for effects at the point of entry to a structure. Locations which 

are also influenced by an incidental or background vibration - heavy rotating·machinery, compressors, etc. should be avoided. 

It is quite common for a householder to request that the instrument 

49 
Vibration Monitoring 

be placed inside a house, or on a window sill. In most cases these 

requests are made because this location is where the vibration was 

most strongly experienced. This request should always be resisted, explaining that any location other than outside the structure will 

not measure incoming ground motion, but only structure response, and that structure response was carefully considered when the OSMRE 

drafted the ground motion regulations. There is no need to be 

reluctant to admit that structure response is sometimes higher than 

the incoming ground motion. If the insistence on an internal 

structural measurement is so great that this request is conceded 

to, make absolutely certain that in these cases any internal 

monitoring is backed up by a proper external ground motion 

measurement as well. 

Sometimes, however, particularly in the case of constant 

recording remotely installed inst~ents, it is desirable to place the instrument inside the structure simply in terms of weather 

protection. A common placement for the transducer in such cases 

will be an internal mounting on a concrete foundation or basement 

wall. In such circumstances it is important to place the 

transducers at approximately the outside surface level on an 

outside concrete basement wall or foundation, preferably at the 

corner intersection that is closest to the blast. A partition wall 

is not suitable because it has a tendency to resonate. 

Normally, the transducers should be placed on a compacted earth 

or soil surface, as close to the foundation of the structure as 

possible, correctly leveled and oriented towards the blast, following the inst~ent . manufacturer's instructions. This 

requirement is so that the planes of measurement are kept in a 

proper and consistent relationship, i.e. that the longitudinal (or radial) component is indeed measured longitudinally, and not 

transversely, to the blast. Some transducer heads have a small 

bubble level to indicate a level position, on other instruments a 

satisfactory calibration cannot be achieved if the heads are not in 

a sufficiently level position. Exact, precise leveling is not 

necessary. 

Coupling is the single most important transducer head placement consideration. If the manufacturer provides a ground coupling spike to be attached to the underside of the transducer head, it 

should always be used providing the ground is at least soft enough for the spike to be pushed fully into place. In addition to this, if at all possible, and even ~~en the vibration levels are expected 

to be quite low, it is always good practice to cover the transducer 

unit with a loosely filled 15 - 25 lbs. sandbag. Burial of the 

transducer unit is sometimes advocated, with soil compacted around 

the transducer head to a depth of at least 2/3 the transducer 

height, but digging a hole will sometimes disturb the soil on which 

the transducer is placed to such an extent that in effect the 

transducer is placed on loose uncompacted soil, and the ground to 

transducer coupling will suffer accordingly. 

50 
Vibration Monitoring 

Figure 22. 

Sandbag and spike transducer head 

to achieve good coupling. 

When high vibrations are expected, special considerations 

apply. Obviously, the risks of ground to transducer decoupling are 

increased, and careful thought must be given to ensuring continuing 

and complete coupling. Some transducer heads are provided with a 

through hole: if a threaded stud is fired or cemented into an 

exposed roc!{ outcrop, the transducer head can be securely bolted 

down, using the storage mounting bolt supplied with the 

instrument. Other methods of secure transducer placement in such 

circumstances include cementing or gluing in place. A very 

suitable and cheap material for this is plaster of paris. This is 

not only very quick, but the bond can easily be broken at the 

conclusion of operations, and the excess plaster remaining can 

easily be removed from the transducer head "'ith no risk of damage 

to the instrument. Care must also be taken to protect the body of 

the instrument from direct exposure to airblast and vibration. It 

should be placed on a soft foam rubber pad, and shielded from 

direct exposure to the incoming airblast shock wave. 

Occasionally, in special circumstances, 

mounted sacrificially with no possibility 

the operation. In such circumstances, 

check the cost of such a sacrificial 

51 

transducers have to be 

of retrieval following 

it is wise not only to 

transducer, but also to 
Vibration Monitoring 

remember that When being fitted with a new transducer head, in all 

probability the instrument will have to be recalibrated. Such 

recalibration costs can be quite significant, sometimes several 

hundred dollars. 

Loose or smooth surface transducer placement should be avoided 

without some sort of coupling support under all circumstances, even 

when the velocities expected will be low, but when acceleration 

levels are expected to be over .2 g's. 

If any decoupling or slippage occurs the results of any 

measurements will be gravely in error. If peak reading instruments 

are used, this will be hard to detect, although with time history 

recordings, such decoupling is normally immediately apparent, 

visible in the waveform "signature". 

Once these basics are complied with, the choices are much as 

were open to the operator for airblast monitoring. 

• Peak only vs. entire t~e history. 

• Permanently or semi-permanently installed vs. portable. 

• Monitoring by consultants. 

The first option, however, is restricted, because of the 

frequency responsive ground motion limitations in the OSMRE 

regulations. Apart from secondary, or backup peak readings taken 

in conjunction with a second time history recording instrument, the 

only times 'peak only' reading instruments are acceptable are: (a) 

when the instruments are used to monitor velocities at points 

within the permit area, when compliance is not an issue anyway, and 

(b) when compliance is being sought under the requirements of 

Sections 816.67(d)(2)(i) and 816.67(d)(3)(ii). 

Similar considerations apply to the decision to use permanently 

installed "constant-recording" instruments, versus portable 

operator attended or set-up instruments, as in the case of airblast 

monitors. An important consideration in the case of ground motion, 

however, is the existence of instruments which may be set-up in the 

field either in a portable or in a "constant-recording" mode. 

Instruments of this type can offer increased versatility. They 

provide the advantages of variable and varying data collection in 

the portable mode, as well as the convenience of use in a 24 hour 

per day monitoring situation, in a fixed location for week or a 

month, or for whatever period might be necessary to deal with any 

particular complaint or concern situation. 

The arguments discussed under AIRBLAST MONITORING concerning 

the relative advantages and disadvantages of seismically triggered 

instruments are also identical. Only the operator can decide just 

what type of instrument is best suited to his needs. Very often 

52 
Vibration Monitoring 

the use of instruments· on a rental basis is the most convenient 

answer to this problem; either because of the ease of switching to 

another instrument without a significant capital expenditure, or, 

as a prelude to purchase, a rental period to serve as a practical field trial. 

Since many of the instruments available today offer a full 

airblast recording capability along with seismic monitoring, all 

the airblast considerations already discussed are pertinent in a 

seismic, or ground motion recording mode. 

Consultants should still be chosen with a great deal of care. 

Ground motion is far better understood among the non-specialist consulting engineers than is airblast, but nevertheless, if the 

decision is taken to retain a consultant for monitoring, it is wise 

to make certain that he is experienced and known in the field. 

53 
Insti'I.Dilentation 

The result is a fonn of bar graph, qn which are recorded deflections from a baseline occurring for each blast or other vibration-producing event. By knowing the sensitivity of the recorder, and the rate of movement of the chart paper, both the peak recorded values and their times of occurrence can be detennined over periods as long as 30 to 60 days. Even if a peak recorder is able to continue to operate unattended for such long periods, it is advisable to remove the records on a much shorter time cycle, in order that excessive vibrations are recorded in a timely fashion, and do not go uncorrected. 

The major advantage of the peak recorder is the low cost and 

simplicity of the equipnent, as well as the fact that it can operate with minimal attention and manpower expense. 

Its major disadvantage is that no frequency information is recorded. Because the potential for structural damage is frequency-related, the data obtained is of limited value, except in 

cases where the vibration levels are so low that damage will not 

occur regardless of frequency. Compliance with OSMRE regulations would only be fully satisfied if the peak particle velocity was lower than 0.2 inches per second, or if compliance was being sought under Section 816.67(d)(2)(i) or (3)(ii). 

Another problem with peak recording inst=ents is that non-blast events, such as bumping the geophone or sl81111ling a nearby door, cannot be distinguished from blast vibrations even though the differences in their wavefonn 1 signatures 1 are quite distinct. Therefore, because of these possible interpretative doubts, the value of these records in damage determination and litigation situations is somewhat limited. In general, the application of these inst=ents should be limited to situations where the 

vibration levels are certain to be low and the potential for complaints is also minimal. Pe&t recorders restrict the choice of the operator in terms of vibration level compliance options. · 

Although peak recorders produce only one trace, containing only peak infonnation, they nevertheless have to record ground motion in all three planes. The ground motion sensors, therefore, still 

.must incorporate three mutually perpendicular geophones. Although the trace will not identify in which plane the peak occurred, OSMRE regulations will be satisfied since the requirement is for maximum 

velocity in any plane. See Note 3/ to Section 816.67(d)(2)(i). Some of these insti'I.Dilents provide a vector sum peak reading. This is also acceptable, since the vector sum velocity will always exceed or equal the maximum any plane velocity. 

56 

. i 
Instnnnentation 

THE I'IAVEFORM RECORDER 

These instruments are the most commonly-used blast monitors. 

They are distinguished by their capability of producing a particle 

velocity analog of a ground vibration waveform. Some have features 

Which allow more sophisticated and accurate c~puterized techniques 

for damage prediction. However, the minimum requirements for 

waveform instnnnents are as follows: 

1. Three mutually perpendicular geophones Which can be 

oriented to sense vibration in the vertical direction, along a 

horizontal line between the blast and the geophone (longitudinal or 

radial), and along a horizontal line at right angles to the other 

two (transverse). This assures that all components of ground 

vibration are sensed by one or more of the geophones and can be 

added vectorally if necessary. This also complies with OSMRE 

regulations, Note 1/ to Section 816-67(d)(2)(i). 

2. The capability of responding to ground vibration 

frequencies of 4Hz or lower, at ±3dB, or do>1n to 5Hz at ±1 dB. 

This assures that all vibration energy within the 4 to 12 Hz 

fundamental frequency range of residential structures will be 

accurately recorded. 

3. The ability to reproduce all frequencies up to at 

least 50 Hz. This enables the accurate determination of both the 

amount of energy in the fundamental frequency range of residential 

structures as well as that energy causing resonance of individual 

walls and other structural elements. This also permits compliance 

with the Blasting Level Chart option, Section 816.67(d)(l•)(i). 

4. The capability of recording 

levels at frequencies up to 200 Hz 

reconrnendations. 

peak ground vibration 

to conform with USBM 

5. A dynamic response range from at least a minimum of 

.OS inch per second to a maximum of no less than 2.0 inches per 

second. 

6. An internally-generated calibration signal Which tests 

the entire system, including the geophones, for accurate 

operation. The instrument's response to this calibration signal 

should be displayed on the record as proof of proper operation and 

to allow for corrections When necessary. Failing this, the 

instnnnent should have recent (within one year) factory calibration 

records, showing calibration traceable to the National Bureau of 

Standards. 

57 
Instrumentation 

7. Unless a separate airblast recorder is used, there 

must be a capability of recording peak airblast with an upper 

frequency limit ~f at least 200 Hz to comply with Section 

816.67(b)(2)(ii). The low frequency limits may vary in accordance 

with the requirements set forth in Section 816.67(b)(l)(i). 

The output of the blast. monitor should be in the form of a 

particle velocity time history record of the event. This time 

history may be generated on-the-spot by an onboard printer or may 

be put on photographic film, tape, diskette or other memory device 

and analyzed at a later time. There are always advantages and 

disadvantages with any system that need to be considered. 

To assure proper analysis and maximize credibility, legal 

experts recommend and some regulatory agencies (but not OSMRE) 

require that independent vibration consultants perform the analyses 

of vibration records. Regardless of whether a record is on film, 

magnetic tape or a field-generated strip chart, all records should 

be analyzed, or at least verified for validity, by a qualified 

person not connected with the mining operator or explosive 

contractor. 

A recent innovation in blast monitoring instrumentation is the 

microprocessor-based unit. This provides a field record by sampling 

the vibration wave at a high rate, storing the sampled values in 

its memory and then printing out these values as strings of points 

on a strip chart so that an approximation of the original waveform 

is drawn. At the same time the peak values sampled fran the 

geophones and microphone are printed out with the waveform to 

provide a peak particle velocity and airblast analysis of the blast. 

This "instant" analysis has the advantage of timeliness, and 

provides a certain amount of information regarding the frequency 

content of the vibration wave. The expense of monitoring is also 

reduced, as long as the operator is not inclined or required to 

obtain a formal verification of the results by an independent 

vibration analyst. 

If evidence of conformance to a single-number particle velocity 

criterion is the only requirement, this method may be 

satisfactory. Low velocities, or velocities measured in accordance 

with Section 816.67(d)(2)(i) or (3)(ii) will conform in these terms. 

Vibration waves are, in general, a complex mixture of many 

frequencies. Visusl examination of a vibration printout is usually 

a rather crude method of determining which frequencies are 

important fran the standpoint of structural dsmage potential. For 

instance, a particle velocity peak may be the result of the 

addition of several frequencies having different significance in 

terms of structural response. On the other hand, important 

58 
InstiUIIE!lltation 

frequencies fran the standpoint of structural respcmse may not be 

apparent by visual examination, because they are masked by other 

less significant frequencies. 

1be implication of this is that conformance to the OSMRE 

frequency dependent criteria shown in Figure 12, page 24, (Fig. 1, 

OSMRE Regulations) can most conveniently and accurately be 

accomplished by a computer technique which separates the vibration 

wave into its component frequencies. There are several methods 

which can be used to accomplish this. It is only through the use 

of such a technique, however, that a valid correlation between 

amplitudes and frequencies can be plotted directly against the 

variable particle velocity limits shown on this graph. 

The seismic information gathered by present-day digital onboard 

waveform printing instiUIIE!llts cannot be supported in this way. 

After the stored digital points are used to plot the particle velocity waveform, the digital information is discarded and no 

further analyses can be performed, except for example by 

"hand-digitizing" the waveform for further separate analysis by 

computer. In such instances, however, hand digitizing error can be 

additive to normal instiUIIE!llt error: great care must be exercised 

with these techniques. 

Future instiUIIE!lltation of this type will no doubt result in 

more relevant and sophisticated analyses than are currently 

available. Such capability is, in fact, within the realm of 

present-day. technology. When it becanes implemented into this type 

of instiUIIE!llt, it will provide the blaster or his consultants with 

a far better insight into the damage potential of ground vibration 

than is currently available using onboard printing instiUIIE!llts. 

Another point to consider is that the need for seismic 

instiUIIE!lltation goe~;~ far beyond the basic control of ground vibration levels and the fulfillment of OSMRE regulatory 

requirements. Civil lawsuits are a comnon result of blasting operations, and the vibration data gathered by the mine operator 

can be crucial in determining the extent to which he may be judged liable. 

When property ~ge lawsuits do occur, it is imperative that 

the mine operator be able to produce seismic evidence that is 

accurate, complete and provable. Opportunities for falsification, 

suppression or other tampering of seismic evidence must be kept to 

a min:inun by whatever means are practical. Evidence demonstrating proof of non-damage is of paramotmt value: in most states, 

lawsuits only have to prove a causatory connection between the 

blast and the damage. Negligence does not have to be proven: it is 

ususlly not an issue. 

59 
Instrumentation 

Experience of lawyers, vibration consultants and other experts 

in the area of blast damage liability has shown that certain 

data-gathering procedures and instrumentation requirements are 

important in establishing the credibility of seismic and airblast 

evidence in litigation proceedings, as follows: 

1. Proof of Calibration: Most instruments have a 

built-in calibration test circuit which checks the continuity and 

accuracy of all data channels. The response of each channel to the 

calibration input signal is printed out, either automatically or on 

command of the operator. The calibration test response pulse 

should be included with every blast record to indicate the accuracy 

of the recording system. 

All seismic instruments should also be shake-table 

calibrated by a competent vibration testing facility at least once 

a year, and a current certification of calibration should be 

provided, traceable to the National Bureau of Standards. 

2. Third-Party Analysis: Blast recordings which provide 

an on-the-spot analysis, or are analyzed by the mine operator, may 

be subject to questions regarding their admissibility in civil 

actions. This question of credibility may, at times, become a very 

important issue because of the potential for a conflict of interest 

on the part of the mine operator. 

This is the reason why it is desirable that the 

analyses of blast records be made by an independent third-party 

expert. Besides minimizing the potential for conflict of interest, 

an expert analyst is able to identi~J problems in recording 

procedures, instrument operation, and blast design that may 

otherwise go unnoticed. 

Third-party expert analysis is a key facet of any 

blast monitoring and structural damage protection. program. Even 

when "instant analysis" type instruments are used, review of these 

records by an independent expert is highly advisable to assure the 

validity of the results and to identify possible problems. 

3. Witnesses: lfuenever a blast is recorded, an 

individual other than a representative of the mining company 

should, if possible, be present to observe the operation of the 

instrument. Ideally, the witness should be familiar with .the 

operation of a blast ~nitor such as a regulatory inspector. 

However, a homeowner, tenant or other interested party might also 

be asked to observe any blast recording to at least substantiate 

the fact that a recording was made. Sometimes local government 

officials or employees can be prevailed upon to undertake this 

function, as can members of the local media. 

60 
Instrumentation 

SUIIWIY OF lllAST VIIRATiotl IIIIUTOII SKCIFICATIONS MD WAIILITI£$. 

C~ny; SlnSithltJ ,,_,., _,_ -~ .. Model; RlngiS: ~H: Sit tate """'" F0n111t: of 

TJpe; settatc: tps, Sll.tc: Ill 

rr.~ ortotn: (Air: ell) l•tr: lid 

Dallas 0..2, G-4, 1·100 • llr griJifl on 30 dly u.s.A. lnstrUMnts: '"' ''" strip dllrt. IA-2·3 I VS-3 PEAK; 

Otlhs ... 1·100 ' MagneUt Tepe CllsttU1 • u.s.A. 

lnstM.IMnts: (100..137) (5-200) Pelt-hOld ..ur IT-4 (2·200 Opt,) ......... WAVEFORM; 

Dalhs 0-4 1·100 ' Jillpt.IC Tapt C.sHtte1, U.S.A. 

tnstn~~~~~nts: (100-137} 1'·100) S(Opt) LQI crt 511111 or puk .... 2-200 Opt,) I'M4tnas. WAVEFORM; 

Df.lhs 0-4 1·100 '·' ~lc T1111 Cluette'. u.s.~~o. 

lnst~: (100·137) , ....,, ST-4 2-200 Opt.) ~ln::: :l ::..~ WAVEFORM; ..... Otllu 0-4 1·100 II,S,A ~~' T'pl cassette • u.s.A. lnstrlllllflts: (100·137} , ..... , IPliJ of s-ry ST-40 2-200 Opt,) data, IIAVEFO~; 

Digital 0•2 5·100 '·' PortaOle printer and U.S.A. Vibration: (100-140) (6-200) u.-.11111 fflll' ,_ry TELEBlAST liata. -.ott besed WAVEFORM; COIPUtfr/plotter for Wl\'lfOI'II data. 

lnstanttl IH ..... 11 4,s,A 111¥tf01"11 &lid •-ry "'""' os-m (100-140) (2·250) b.r pen prlnttr/plotter, 

WAVEFORM; COIIputer typl ktJbolrcl, 

Philip R. 0-Z 5·100 • 111\'lfol'll :3: direct u.s.A. ....... (llu 145) (6-200) photo prl clllrt Associates: """'*". UD readout SSU II WAVEFORM; of stiSIIIC peeks, 

Philip R. 0·4 ..... '·' WtwtfCII"'I and ~ry dlta .... ~. (110·140) """' (2-256) 11.r onbolrd clot-411trt• Associates: ~~printer. 

ssu 10000 T.r,..,.ttr styl• ktyboln: 

WAVEFORM; ... 1. 

""' 0·20 5-150 ' 111\'lfO'f'll by onbolrcl u.s.~~o. 

Indicator '"'X 1621 (1·!50) dlrtct phDto print 7- S-2 I S-35 IS gain cllannel clllrt recorder. WAVEFORM: settings) 

""' "" 5-100 '·' "'" fC1r11t!lll,_rr u.s.A. Indicator (llu 168) (5-aoG) dilta 11.r onbolrd strip 

••• WII.VEFORM: ::;,L:t!~'ru~Kf lnttrlact for u:terl'lll printer or COIIPUtfr, 

Sprengnathtlr o-s .. .., ' Wl'141f0'1'11 by onboarcl photo U.S.A. Insti'UIIellts: (Opt.) (Opt,) print chllrt recordtr. '15·1200 

WAVEFORM: 

Sprengntthtr 0-6.4 4·"" '·' WlvtfO'f'll lit' onbolrd photo U.S.A. lnstr.-nts: (MIX, 140) (2-200) print clllrt recorder. LCD \'5·1600 

W.VEFORM: dhpliJ of .-ry dltt 

VI bra-Tech/ 0-4 ... ., ' Mlgnetlc tape casstttel, U.S.A, 

~~.v~~4 (100·140) (5-250) "--k-llold •ttr .,... dlta capt-. VOice on Strlts 2000 sound clllnnal capability. WAVEFORM: 

Vlbr1·Tech/ o-4 2·200 '·' Digital grade ~It U.S, A, 

~~v:t;s (100-140) (5-500) tiP' cnstttl. L read- out of ,_ry data. 5000 EVERlERT Tape rnllllck facntty. 

Wo\VEFOIIM; 

Vlbra·Tech/ 0·.5,1 or 2 .. .., ' 8lr graph on 30 dily strip U.S. II.. 

""' Fa~~~ set cllltt, with llovrly tltlng SEISTECTOR (N/A) •rtts. PEAK; 

Vlbra·Ttch/ 0·4 5-100 ' Vl'llfQnl b1 ~rd U.S.II.. .. , (llu 140) (5-2001 photo prl nt chart VR Model F 

IIAVEFOIIN; "'-· 

Vlbrl· Ttch/ 0-4 .... ' 11awef0t11 by onbolrd u.s.A. 

""' '"' '"' photo prl nt chart VR Model & recorder. WAVEFORM: 

Hotts: 30 tinute tlpt IIDI'IIITl.r ~ b! •nufecturtr, TIM history, frtqutnc-~· bill ding rQIIOIIW IIIII cotpvter 

::lr!:~.~:_. a:.sulta:~Y responstwe criteria 

3 Selectable weloclty, diSJ~lac-.nt •d acceltratiol! output, 5h gain sttt1ngs. 7 SKand recording Plf'lod in ....utl aodl. Modal S·3 hiS selectablt vtloctty, dhDiate.nt and acceleration outputs. 

"" Rteord/Racall 

"Option No." SUitability: Capabllltle~: 

1 and 3 Jill~ COIIPOM"t continuous 

r.eordlng, Vector ,. optional. 

1 lnd 3, 3 COIIPOntnt seh•t c and also 4 If air data stored on tape2. 

::t:d. 

I and 3, also 4 If 3 cOIII)OI'IIIlt stiYIIC tnd 

air data stored on tape2. 

-""' analysed. 

1 llld 3, 3 cOIIPQI'III'It seh•lc, air abo 4 If and s~ry diU stored 

==· on t1 • 

1 and 3, 3 COIIIPOIIfllt st\SIII,, air also 4 If and s-ry data stored 

'-~ on tape2, 9t event ,_, analysed. :.~~~~~tq~~~r. 

1,3 and 4 3 tOIIPOnent stlsal' IIIII air. Dlal·up phont link central ca.puter/prlnter /disc data stor1111. 

I I 3, +4 3 co.pon .. t stis•lc, air If 111111.111ly and s-ry data on Plptr 

dlgltlzed printout, 50 ewtnt allto. 

I"' recording, Continuous c01lplltltY'. recorder optional. 

1,3 and 4 3 COIIIpOMIIt SlfMIIC and air on p.1per printout. 

1 lnd 3, 3 cOIII)Otlant sets•tc, air also 4 If :r'1 nf=~rlo 11 ,_..,. :!!:' a:r.'" analysed. 111ttc r«:ordlng per paper 

1,3and4 TIIO l COiq)OIIfflt se1s-1c clll.nne\s 1nd optional air on paper printout. 

1,3 lnd 4 1Wo 3 COIIPQntnt st\MIIt channtls l opt1o1111 air. Three storagefrecall 

-·· 1 I 3, +4 3 COIJII)QIIInt seiYic on if •~ually ~~&Pit printout. 

dlgitl.r:ed 

I"" COIII)Uttr, 

1 I 3, t4 3 c011ponent sels•lc on If •nu.lly paper printout. 

digitized 

I"' CQIIIPUtfr. 

1,3and4 3 ca.po~~e~~t selstlc and air data stored on llllgnttic tapel, 

1,3 Ond 4 3 COIII)OI'IInt sels•lc, air and su.ary data stored on tape. Field recall of all SIIDBry tape data lncludi"'IJ tl• 1 d1te. 

I and 3 Max. COIIPOIIfllt (or vector su.) continuous recording, 

I l 3, +4 3 COIIPQnent $ti51111C lnd If •nually air on paper printout. 

digit heel 

l•t<> 

cotpUter. 

1 I 3, +4 3 COIIpOntllt set SII\C If •nually on paper printout. 

digitized 

l•t<> 

c011111ter. 

Table 4. 

61 

Ava11abtllty of '''" ..... Fig, 

'""""' Requlr811ents: (lbs) 

lnfiii'Wtlon: "· 

.,M. 3 • 6V Lantern 25 23 INittery. Ext.DC IIO'Ifel" pluv. 

Visual esliMte ttrru 3 ll h Lantern 

selsqrfl• tOI(Iuter " " 

anllys\s . 

VIsual estllllU tllru t2V rechar,e· .. !~~~~· CQIIPuter able INittery. "" ht. oc power. 

Vlsu.l estillllltt tllru 12w r«:hlrgt· " 25 

!~~r:'· COIIputtr tble battery. ht. oc power • 

Vlsual utt .. tt thru 12v rectw~~·- " 16 

:!~r:· Collputer lble bettery. ht. DC power. 

Olr«:t data lntiiT'flct 110V AC with 42 Z7(a) w1 th c011p11ter for standby 24V 27(b) tiM·hhtory, FourlltY' battery. I response analysis. 21(c) 

VIsual tstlllllltt thru 8V J"Khergt~blt 42 stlsqrlll. lllnual battery. E~t.OC '" 

digitizing req, for .,_r plijg, 2nd COIIIPUtiiT' analysts. IN blttery req, for opt. heater. 

VIsual tstiNte thru 12Vreclll~ 16 28 stls-ov•. lllnual ablt battery. 

61gitl.r:lng rtCIUlrtd for ~tar analysls 

VIsual estl•te thru 6V rechargeable selsqr.-, lllnual batttry. httr- " " 

digltl.r:lng req, for nal DC powtr, 

COIIIP\ItfT' .tnalysts • 

Vlsl.lll tstiMte thru 1 zv retllarge- 50 

digitizing 

selsqr•. required 

Menual able battltY'Y. " • for COIIPUtfr analysis " 

Sptctr41 ...-gy rtc- 12V reclllrge-- orded within 11 frt- ablt battel"y. " " quency bends. ( 13 for air) Dlrtct COIIPUter lnterfact for analy- s1s of 111v.for.. dlta. 

VI sua! tstl•te tllru 12'1 ~harge· 52.5 33 sels-.ogr.-. lllnual ablt battery. 

digitizing l"tqllired for CO!lfUter analysh 

VIsual tstllllllta tllru IZV recharge- lO sel SIIIO!I"•· Menual abla battery. " 

digitizing requirtd for COIIPIItlr anelys\s 

Viswl tstl .. tt thru 2 x 6V Lantern 28 sels-.ogr.-. Dl rect " 

ct:nputtr analysts batteries. 

avalhble. 

Visual est111te thru 2 x 6Y recharge· " ~ 

seh~a. Dl rect lble Lantern 

inttrface with COli-- batteries. Ext. 

puttr for cotplete oc power supply 

an1lysls. I clllrger unit. 

.... 110VAC with 8 hr 10 

f!:=~ed~t:-y " 12V ext. battery 

Visual estiMte thru 12'1 rech•rveselsqr•. lllnual 1ble battery. " "' 

digitizing required 

fQr conputer analysts 

VIsual estiNte thru 1 h recharge- 35 selgogr1111. ,_nual eble battery. " 

digitizing required for CCM~pUter an~lysls 
lr;strumentation 

Table 4, on page 61, is a SUJJDaiY of mst of the instruments 

found in the field today including general descriptions of their 

important features, advantages and limitations. It is important to 

emphasize that these descriptions are, of necessity, very general. 

Many subtle differences exist in the design details of similar type 

instruments. Some of these differences may be insignificant for 

one application but vitally important in another. Engineering 

changes are also made regularly within given models to improve 

their operation and take advantage of.technology advances. This 

is particularly true for the newer microprocessor-based models 

where software changes can be made which change their capabilities 

without any change in hardware. · 

It is therefore recommended that whenever instrument 

capabilities are in question, the manufacturer or the appropriate 

consultant should be contacted to obtain information regarding a 

specific instrument and the suitability of its intended application. 

The illustrations contained in the following pages show alJOOst 

all of the instruments described in Table 4 on page 61, and are 

referenced in the last column of that table. 

62 
Instrumentation 

Figure 23. 

Dallas Instruments VS-3. 

Figure 24. 

Dallas Instruments BT4-B. 

63 
Instrumentation 

Figure 26. 

Dallas Instruments ST-4D. 

64 
Instrumentation 

-------

T.ELE--BLA 

Digital v·b ST 

I ration I 

, nc. 

Figure 27(a). 

Digital Vibration Teleblast. 

Figure 27(b). 

Digital Vibration Teleblast. 

65 
Instnnnentation 

Figure 27(c). 

Digital Vibration Teleblast. 

Figure 28. 

Philip R. Berger & Associates SSU II. 

66 
Instrumentation 

Figure 29. · Philip R. Berger & Associates SSU 10000. 

Figure 30. 

Slope Indicator S-2. 

67 
Instrumentation 

Figure 31. 

Slope Indicator S-3. 

Figure 32. 

Slope Indicator S-6. 

68 
Instrumentation 

Figure 33. 

Sprengnether Instruments VS-1200. 

Figure 34. 

Sprengnether Instruments VS-1600. 
Instrumentation 

Figure 35. 

........ -

Vibra-Tech/VME Vibra-Tape® GMS-4. 

Figure 36. 

Vibra-Tech/VME Vibra-Tape® Series 5000. 

70 
Instrumentation 

Figure 37. 

Vibra-Tech/VME Seistector~. 

Figure 38. 

Vibra-Tech/VME VR Model 'F'. 

71 
Instrumentation 

Figure 39. 

Vibra-Tech/VME VR Model 'G'. 

72 
CHAPrER 9 

COMPLIANCE OPIIONS AVAILABLE TO THE OPERATOR 

GROUND OOTION 

The OSMRE regulations allow the operator to choose from four 

optional methods to control ground vibration: 

1. Section 816.67(d)(2)(i) Maximum Peak Particle Velocity: 

Provid:i.ng that each shot is monitored, and a seismograph record is 

provided, this first option is DISTANCE related, and requires 

merely that: 

(a) From 0-300 ft. distance: max. PV = 1.25" /sec. 

(b) From 301-5000 ft. distance: max. PV = 1.00"/sec. 

(c) From 5001 ft. to beyond: max. PV = 0.75"/sec. 

2. Section 816.67(d)(3)(i) Scaled Distance EQuation: 

This method does not require that blasts be monitored, but it 

relates a permissible MINIMUM SCALED DISTANCE (Ds) to DISTANCE, and 

requires adherence to these as follows: 

(a) From 0-300 ft. distance: min. Ds = 50 

(b) From 301-5000 ft. distance: min. Ds = 55 

(c) From 5001 ft. to beyond: min. Ds = 65 

3. Section 816.67(d)(3)(ii) Modified Scaled Distance: 

This is not distance related, but is based upon the collection of 

site specific data, and the statistical analysis of this data, 

using the predictive methods covered in the "PREDICTION AND CONTROL 

METHODS" Chapter in this manual. 

4. Section 816.67(d)(4)(i) and (ii) Blasting Level Chart: 

This is the most precise, and also the most unrestrictive option 

available to the operator. It requires the monitoring, recording 

and analysis techniques that provide complete frequency 

informstion, since the vibration limitations imposed, up to 2.0 

inches per second, are frequency related. 

Discussing these options in order, and referring to them 

throughout this manual, and in Table· 4. (Page 61, Instrumentation) 

as Options 1, 2, 3 or 4, H is possible to detail them, together 

with their" advantages and disadvantages. 

73 
Available Compliance Options 

OPTION 1 : MAXIMUM PEAK PARTICLE VELOCITY 

This option, and option 2, Scaled Distance equation, might at 

first sight appear to be illogical in that the closer a structure 

is to the blast, the higher the velocity (or lower the scaled 

distance) that is allowed. Common sense would seem to advise the 

reverse. However, because of the fact that higher frequencies are 

less damaging to structures than lower frequencies, and that the 

closer to a blast, the higher are the frequencies, this regulation 

is, in fact, perfectly reasonable. 

Option 1 is the simpler of the options that require monitoring 

on a permanent basis, and will permit the second highest vibration 

levels. It only requires peak effect monitoring, without any 

frequency reference, and all of the measurements can be made at, or 

outside, the permit area, usually at the particular structure of 

concern. 

OPTION 1 ADVANTAGES: 

• "Peak only" reading instruments are acceptable. 

• No frequency information is needed. 

• Little operator expense involvement. 

• Maximum PV of up to 1.25" /sec. are allm•ed at 

short distances (when higher maximums may be 

more useful) • 

• Generally permits shorter distances and/or higher 

charges per delay than the scaled distance options. 

OPTION 1 DISADVANTAGES: 

• Every shot must be monitored. 

• Does not permit the maximum velocities allowed under 

option 4. 

• Fach shot might have to be monitored in two or more 

separate locations, dependent on distances. 

• If peak only reading instruments are used, will not 

assist in identifying. potential blasting problems. 

74 
Available Compliance Options 

OPTION 2: SCALED DISTANCE EQUATION 

Option 2 is the only non-site specific option, and therefore, 

being based on generalized data collected over the whole of the 

U.S., it is the most restrictive, although it is undoubtedly the 

simplest of all the ground motion compliance options. It requires 

only that the distance from the shot to the point or structure of 

interest is related to the maximum charge weight per delay, as a 

square root scaled distance, thus: 

!z 

Ds = D/W 

Where D = the distance, in feet; and 

W = the maximum charge weight per 8 ms. delay 

period, in lbs. 

Since this formula can be rewritten: 

W = (D/Ds) 2 

then, substituting Ds according to the re~lation and the actual 

distance, it becomes easy to calculate a maximum charge weight per 

delay allowable at that distance. 

The following table shows allowable maxiQum charge weights per 

delay under this regulation, at various distances: 

DISTANCE-FT MINIMUM Ds MAX. CHARGE WT/DELAY, LBS. 

100 50 4.0 

300 50 36.0 

310 55 31.8 

330 55 36.0 

500 55 82.6 

1,000 55 330.6 

2,000 55 1 '322. 3 

5,000 55 8,264.5 

5 '1 00 65 6,156.2 

5,900 65 8' 239.1 

6,000 65 8,520.7 

10,000 65 23,668.6 

The above figures naturally show some anomalies at the 

regulatory Ds change distances of 301 ft. and 5001 ft. ; however, 

since it is most likely that when this option is adopted the 

conditions will not be critical, and the distances will probably be 

over 2 or 3 thousand feet, this is of no great consequence. The 

regulation itself is written to allow blasting at distances less 

than 300 ft., with no minimum distance stipulated, provided that 

the requirements of Section 761.1l(e) are complied with (mainly 

that the owner of any occupied dwelling within a radius of 300 feet 

75 
Available Compliance Options 

has provided a written waiver consenting to such operations). Although the regulation allows a minimum scaled distance at these 

short distances, the charge weights per delay permissible are 

usually too small to permit any practical production mine 

blasting. Really effective control of blast vibrations at short 

distances is far better left to Option 4, the Blasting Level Chart. 

"Whenever blasting is carried out, and instruments are not used 

to record the vibrations, it becomes increasingly important for the 

operator to take all possible steps to reduce ground motion and 

airblast. It is therefore imperative, when monitoring is not being done, that utmost care be taken to minimize vibrations. (See pages 33, 35, 40, 41, 42, 43 and 44, and Figures 14 to 17 in this manual). 

OPTION 2 ADVANIAGFS: 

• No monitoring is required. 

• Simple scaled distance control only. 

• Minimum cost. 

OPTION 2 DISADVANTAGES: 

• The most restrictive of all the options. 

• Not related to actual velocities: 

least effective protection in the event 

of complaint situations. 

• Impractical at short distances. 

• Only effective under non-critical 

distance/charge weight relationships. 

• Will not assist in identifying potential blasting problems. 

OPTION 3: K>DIFIED SCALED DISTANCE 

This, and option 4, are far more effective under more critical 

conditions than is option 2. Both options 1 and 3 rely on site 

specific measurements, but option 3 translates these measurements 

into a statistically predictive scaled distance, with a confidence 

level of 95%. This avoids the need for regular monitoring of every 

76 
Available Compliance Options 

shot, although it must be stated here that once a modified scaled 

distance is authorized by the regulatory authority, it must be 

subject to periodic review and renewal. This is discussed 

specifically later in this chapter. 

The methods by Which the site specific vibration measurements 

are converted into a scaled distance formula are detailed in this 

manual's Chapter 10 on PREDICTION AND CONTROL METIIODS. Computer and calculator programs are provided in Appendix 'A' (pages 135 to 

165) for those who wish to process their own data, although it is 

recommended that this type of predictive work be done, if possible, by experienced blast vibration consultants, because of the many 

pitfalls that can beset the inexperienced venturer in this field. 

For the purposes of this section, however, these methods will 

be described only in outline, with emphasis being placed on 

compliance, and their relative advantages and disadvantages to the 

operator, as has already been done for options 1 and 2. 

The fi~st point that must be firmly established regarding option 3 concerns the amount of data that is needed to assure 

authorization of a modified scaled distance. The answer to this is 

complex: 

It must be realized that when statistical sources are consulted 

for the answer to this question, they only provide the information 

that the 'n' value, the number of data pairs required for a valid 

statistical analysis, should be "large". For the . purposes of this 

manual's guidance, 30 or more data pairs will be considered a 

suitably large 'n' value. Therefore, the following qualified 

answer is offered: 

If the data is good; a minimum of 30 data pairs are acceptable. 

Obviously, the real qualifier is the goodness of the data. 

There is a simple solution to the problem, however, based on the 

fact that the prediction methods used work very well provided the 

data used is collected sensibly, accurately, and consistently. Therefore, when embarking on a program to collect data to form the 

basis for an authorized modified scaled distance, these basic rules 

must be adhered to: 

1. Remember that the data pairs needed are peak particle velocity versus scaled distance. So as to properly utilize options, scaled distance data must be collected as distance in feet with 

maxinrum pounds of explosive per delay period. 

77 
Available Compliance Options 

2. When collecting scaled distance data, do so on the 

basis of: 

(a) Measured distances (NOT GUESSED). 

(b) Measured explosive weights (NOT GUESSED). 

Careful explanition to the blasting crew of the 

methods and purposes will help here. Do not simply rely on the 

figures written on the reports; check personally to see that they 

are factual. 

3. When recording blast vibration data, do so on the 

basis of the maximum peak particle velocity that occurred in any 

plane, for each shot. One instrument recording is required for 

each velocity data point. If more data is required, per blast, then 

more instruments nrust be used. 

4. Separately identifiable data should be recorded for 

coal shots and overburden shots. Sometimes the characteristics 

will be close enough between the two to permit a common scaled 

distance fornrula, but frequently this is not the case. Other 

similar significant geological variations will also require 

separation of the data in this way. 

5. Collect data at as wide a range of scaled distances as 

possible: see remarks on this subject on Pages 48 and 49, and also 

on Page 133, Appendix 'A'. In any event, data MJST be collected at 

at least as low a scaled distance as it is hoped will be authorized 

and preferably lower than this. 

6. Collect data at an even spread of scaled distances 

between the highest and the lowest. 

7. Collect data consistently, using the same 

instrumentation, recording it in the same geological formations, 

and avoiding interposed features that might cause higher or lower 

than normal results, such as streams, hills or excavated areas, 

etc. (See Figure 56. in Appendix 'A', page 131.) 

8. Exclude data where it is known that conditions were 

not normal. For example, if it were known that propagation 

occurred, or if there were misfires, etc. 

Once these rules are observed, it will be found that the 

collected data is good. If problems persist in terms of getting 

good data, then it is time to start looking for problems that may 

not be known to exist. The fact is that careful monitoring can 

lead to a more efficient and trouble-free operation, and this 

should be encouragement and motivation in itself. 

78 
Available Compliance Options 

The final results of these calculations, together with the 

supporting data, must be submitted to the regulatory authority for 

approval. Authorization for a modified scaled distance will be 

forthcoming, as long as the data is good; as long as there are 

sufficient data pairs, and if the calculations are correct. 

Once a modified scaled distance has been authorized, it must be 

reviewed and renewed from time to time. This is one point that is 

not covered by the regulations, although it is of great 

importance. Particularly on the Iarger surface mines, the area in 

Which today's operations are taking place may be a significant distance from the area in Which last year's operations took place. The geographic and geological differences can well mean that the 

site specific formula for last year is no longer specific to this 

year's site. 

It is recommended that modified scaled distances be reviewed, 

updated if necessary, and re-authorized at least annually. The 

data required for this would be as for any initial modified scaled 

distance application. 

Although this third option would seem to require a great deal 

of effort and application, it provides a site specific velocity attenuation formula that can be of inestimable value in the event 

of complaints from unexpected quarters - and sometimes great 

distances. Where it might have been thought quite unnecessary to 

monitor, a complaint situation frequently will cause the operator 

to wish he had had the foresight to have taken some readings at the 

complaint site. The existence of a site specific attenuation 

formula will offset this omission to a very large degree, since 

instead of a site specific measurement, a calculation based on the 

attenuation formula can often establish clearly that a damage situation was not possible. 

OPTION 3 ADVANTAGES: 

• No regular monitoring required. 

• "Peak only" instruments acceptable. 

•.No frequency information needed. 

• Maximum of 1.25 inches per second allowed 

at short distances, based on the site specific 

rather than general data. 

• Provides reasonable protection in complaint 

situations. 

79 
Available Compliance Options 

OPIION 3 DISADVANTAGES: 

• Does not offer minimum restriction to operations. 

• Must be reviewed and renewed at least annually. 

• Offers less complaint or lawsuit protection than 

frequency responsive methods. 

OPIION 4: BLASTI!ii LEVEL CHART 

This is undoubtedly the least restrictive of the four available 

options and although it may appear to be the most costly, it can 

offer the most in side benefits and cost savings to the operator. 

Every shot must be monitored, and a frequency responsive instrument must be used. As has already been discussed, however, the advantages that accrue from the use of such instruments should 

not pose too great an additional burden in this respect. In 

addition to this, the latest computer analysis techniques provide 

an easy to understand (and easy to verify) graphic representation, 

so that compliance can be checked at a glance. Figure 40, which 

shows a typical computer analysis printout for a Vibra-Tech GMS-4 

Analog blasting seismograph, illustrates this point. For each of 

the three planes, the computer will print out a particle velocity 

versus frequency graph, very similar to the Figure 1. (OSMRE Regulations) Blasting level Chart, complete with the frequency responsive maximum velocity indication on it. As long as the 

velocity versus frequency graph lies below the maximum velocity limit line, it is a clear indication that the vibrations are in 

compliance. 

, .................. ,, .. 

:"OfiU••o.Utol-

----------------- ~-.. ··-....... ,_ 

--------·~·--~ ---------

otno'""'"''· 

-, .. _ 

_ 1 ·r:~~:~-~~- ·-------------· 

. -- ,,-,_~---.. -.--.. ~.- .... ·-- '"' .. """" n...-oH .. ,_, nu'"""' 

Figure 40. 

Typical computer printout of blast vibration waveforms. 

80 
Available Compliance Options 

The data gathered when this option is exercised are also the 

most useful, both in terms of protection from damage claims and lawsuits, and also for predictive purposes. Since the frequency at 

which the maximum vibrations occur is known, in all three planes, the possible effects will also be much easier to demonstrate and to predict. 

When nore critical conditions are approached, at closer distances, the predominant frequencies of the ground motion tend to 

get higher. Therefore, in general, it will be found that the closer the blasting is to a structure, the higher are the permitted velocities. When at or over 30 Hz, 2 inches per second is permitted. When this higher velocity limitation is coupled to the fact that any predictive exercises are based on current site specific information, it will be realized how far less restrictive 

to the operator this last option is. 

It should be noted at this point that frequency determination is not a simple procedure, as careful scrutiny of Figure 40 will confirm. If reference is made to the preamble to the Rules and Regulations (Federal Register, Vol 48, No.46, Tuesday March 8, 1983) on page 9802 OSt·IRE states: 

"Co11Il1enters requested clarification as to what was required to evaluate blast vibration frequency. They wanted to know whether visual inspection of seismographic records was adequate or whether electronic analysis of frequency would be required. Under Section 816.67(d)(4), which requires regulatory authority approval of the method of analysis of the predominant frequency contained in the blasting records, visual inspection may be adequate if traces are distinct and only a few frequencies are contained in the wave-form. However seismographic consultants have found that various waves lvith multiple frequencies typically are contained in the blasting record. In those cases, electronic analysis is necessary to 

separate the wave traces and analyze each intensity and frequency. OSM does not intend to mandate electronic analysis; rather the determination of what type of analysis is appropriate should be made by the regulatory authority .... Except when the criteria of Section 816.67(d)(4) are used, the final rule leaves frequency analysis to the discretion of the regulatory authority. OSM recognizes its value as an indicator of vibration damage probability, but also recognizes the complexity and expense in its application .... " 

This fourth option can be most usefully employed if it is used in conjunction with the predictive techniques described in Chapter 10, PREDICTION AND CONTROL METHODS. Quite apart from the benefits that these techniques provide when unexpected or unusual complaint 

81 
Available Compliance Options 

situations arise, they are the only methods that permit blasts to be detonated, knowing in advance that velocity limitations will not be exceeded. Once that capability is properly UiideistOOd, ana these techniques are utilized to the full, the guesswork and 

uncertainty in blast design can be virtually eliminated, certainly as far as vibrations are concerned. A distance will be known, and 

it will be known from previous records just what the predominant frequencies will be. The maximum permissible peak particle velocity can then be found, and, using the regression techniques mentioned, a safe scaled distance, relative not only to those exact site characteristics, but to that particular shot, can be 

established. Once that is known, the blaster can be told his maximum permissible charge weight per delay. He is then totally free to design his shot, with an absolute minimum of restrictions. He can always, therefore, work to the optimum conditions. The shot is monitored, for confirmation of compliance, and the new data is added to the old data and run through the predictive techniques once more, so that the next shot will again be based on totally up-to-date and current predictive information. 

Notwithstanding the apparent - and actual - effort involved with this option, it will be found that this effort will be amply repaid in terms of minimum restrictions, optimum blasting efficiency, maximum protection and complete compliance. 

OPTION 4 ADVANIAGES: 

• Least restrictive: permits highest velocities, maximum loadings and shortest distances. 

• Permits greatest freedom in blast design. 

• Greater freedom in blast design can result in lower drilling costs, optimum drilling and blasting efficiency. 

• Maximum liability protection. 

• Complete compliance. 

• Greatest total savings. 

• Employs OSMRE encouraged use of response spectra (see page 81). 

• Provides OS!1RE approved evidence of regulatory compliance and damage potential. 

82 
Available Compliance Options 

OPTION 4 DISADVANTAGES: 

• Every shot must be monitored. 

• The instrument must be frequency responsive. 

• Highest cost, neglecting possible savings offset. 

• Needs careful and thorough implementation. 

When considering any of the above options, only the operator can really decide what is best for his own particular situation. The simplest and cheapest options tend to be more restrictive, and 

do not offer the side benefits that frequently moderate the 

apparent cost and effort involved in the less restrictive options. 

83 
CHAPTER 10 

PREDICTION AND CONrROL ME'IliODS 

When any monitoring methods are carried out that collect 

vibration data against distance and explosive weight data, it is 

possible to analyze that data in such a way that it becomes an 

indicator of the vibration effects for future blasting and not 

merely a record of past events. Since it is obviously better to 

know in advance whether blast vibrations will be excessive, rather 

than merely to record them hopefully, these prediction and control 

methods are presented as the core of efficient, safe and 

responsible blasting operations. 

Whether the purpose is to develop a modified scaled distance, 

for compliance under Section 816.67(d)(3)(ii), or to ensure that 

the limits imposed under Section 816.67(d)(Z)(i) or (4)(i) and (ii) will not be exceeded, or simply to control critical blasting 

effects, the basic technique is the same. The underlying principle is that each mine or blasting site is different from another, and 

that minor differences exist within each site, such as the geology and techniques of blasting, hole size and depth, drill and blast 

pattern, and blast hole loads, in addition to the location and 

distance to structures of concern. 

Scaled Distance (Ds) is a fundamental relationship between 

distance in feet from the blast to the recording instrument or 

point of concern and the maximum explosive charge weight in pounda 

per 8 ms delay period. It is expressed as the distance, feet, divided by the square root of the charge weight per delay, potmds, 

thus: 

!, 

2 

Ds = D/W 

When statistical analysis techniques are applied to blast 

vibration data pairs, peak particle velocity against the scaled 

distance at which that velocity was measured, a site specific velocity attenuation formula can be developed. The technique is 

known as a least squares regression analysis, and the velocity attenuation formula takes the form: 

13 

V = H(Ds) 

where V = peak particle velocity, inches/second, 

H = particle velocity ('y' axis) intercept 

at Ds = 1.0, 

Ds = scaled distance, and 

S = curve slope (decay exponent - always negative). 

85 
Prediction and Control Methods 

The variable values H and S are constants for each particular site: each regression analysis carried out on the PV/Ds data pairs will determine a specific value for each of these terms. Generally speaking, H can vary between perhaps as low as 20 or 30 to as high 

as 1000 or more. The slope 13 will normally be no lower than -l.l 

or -1.2 or so, and will sometimes be as high as -2.2 or -2.4. The 

often quoted and referenced general use velocity attenuation 

formula published in the DuPont Blasters' Handbook (16th Edition, 

p. 426) is: 

-1.6 

V = 160(Ds) 

This is of course, very conservative, and is not site specific, being derived from data obtained over a very wide range of 

geographically and geologically different blasting sites. 

Conservative as this formula is, it is not as conservative or 

limiting as the dictates of Section 816.67(d)(2)(i) and (3)(i). The following table relates the two and indicates the need for 

proper site specific velocity determination and prediction techniques, whenever the local conditions are anything more than 

completely non-critical: 

DISTANCE Ds(3)(i) PV(2)(i) (Permitted) PV (DuPONT FORMULA) (Probable max. actual) 

0-300 ft. 50 1.25"/sec. 0.30"/sec. 301-5000 ft. 55 1.00"/sec. 0.26"/sec. 5000 ft. + 65 0.75"/sec. 0.20"/sec. 

It is this type of restriction - essential when no monitoring is to take place - that can be circumvented and replaced by site 

specific, factual and far less restrictive compliance options when 

prediction and control methods are fully exploited. 

A plot of particle velocity versus scaled distance is a complex curved line on linear graph paper. To show this relationship as a 

straight line, and to compress a wide range of values onto a single sheet, the plot is made on logarithmic co-ordinates. The slope of 

the curve, being negative, shows that as the scaled distance 

increases, the peak particle velocity decreases. 

The data pairs, carefully and systematically collected as 

discussed in Chapter 9 (Compliance Options: Modified Scaled 

86 
Prediction and Control Methods 

Distance) are input to the regression analysis calculation, which 

can be perfonned on any small computer, or even a progranmable calculator. The resultant equation is for a geometric curve in the 

fonn: 

b 

Y =ax 

or: 

log y = log a + b log x 

which shows a linear relationship between both x and y in terms of logarithms. Drawn on 3 cycle "log-log" paper, the curve can be represented as a straight line, and can accommodate a scaled distance range of 1 to 1000, and a peak particle velocity range of 0.01 to 10.0 inches per second. 

The statistical confidence level adjustment procedures described in this manual are those commonly used throughout the blast vibration control profession, and therefore: 

• If the data collection methods recommended in this manual 

are closely adhered to, 

• If at,least thirty data pairs are obtained (preferably in excess of thirty), 

• If the data is properly distributed, 

• If appropriate distinction is made between coal, overburden, and presplit blasts, and 

• If the topography between the blast and seismograph is sensibly considered, 

then the regulatory limits will not be exceeded. 

To assure the reliability of the equation, the attenuation fonnula must be adjusted statistically to a 95% confidence level, and the 'goodness of fit' or coefficient of determination (r 2 ) of the data should be no less than 0.7. The standard deviation, used in establishing the confidence level, should be as close as possible to zero. In actual fact, it is not likely under practical conditions that the standard deviation will be less than 0.2, but it should not be much greater than 0.5 or so. 

If the standard deviation becomes too large, the H variable of the attenuation fonnula will increase to the point that the 95% confidence level will only be attainable at large scaled distances, approaching the non-site specific scaled distances allowable under Section 816.67(d)(3)(i). In order to derive maximum benefit, in this respect, the standard deviation should be reasonably low. 

87 
Prediction and Control Methods 

When the goodness of fit is too low, below 0.7 or so, this is an 

indication that there is some problem or inconsistency in the 

data. When this occurs, a review of the data and test procedures is advisable, and a series of additional tests must be carried out. 

Even if the data is not usahle in a predictive manner, or if a 

modified scaled distance cannot be established in this way, the 

results are. still of great value. This might be the situation 

where the analysis, while not providing the looked for results, has 

nevertheless made a clear statement that must not be ignored: 

"THE DATA IS NOT GOOD! wok for a problem that may exist in the data collection, recording methods, drilling and blasting procedures, or blast design." 

While this may not actually identify the problem, it has 

alerted the operator to the fact that a problem exists. If he then 

reviews his records and procedures, if he then looks for the 

difficulty, the chances are very good that some sort of 

inconsistency or deviation will be found. Once identified in this 

way, corrective action can be taken, and a problem will be resolved 

which otherwise would have gone unrecognized. 

The resultant information should never be regarded as final, as 

long as some ongoing vibration monitoring is to take place. As 

soon as new data becomes available, it may be added to the old, and 

the attenuation formula, and supporting information, constantly updated for optimum reliability. 

PREDICTIVE DATA: USAGE FOR MODIFIED Ds 

Once a minimum of 30 data pairs has been collected and the 

regression analysis performed, by the mine operator or by an 

independent consultant, the analysis and supporting data must be 

submitted to the appropriate regulatory authority. On approval, a 

specific attenuation formula will be authorized for use at the 

location where the data was collected. 

In order to determine exactly what modified scaled distance 

must be used in planning the blast, the distance to the structure 

of interest or concern must be known, so that the appropriate maximum peak particle velocity may be arrived at under Section 

816.67(d)(2)(i). 

Let it be supposed, for example, that the distance in question 

was 1385 ft. From the regulation, at this distance the maximum 

allowable peak particle velocity would be: 

1.00 inch/second. 

88 
Prediction and Control Methods 

Let it also be ·supposed that the site specific attenuation 

formula derived from the collected data was: 

-1.51 

V = 149.2(Ds) 

Since this formula can be rewritten: 

1/1.51 

Ds = (149.2/V) 

substituting the allowable 1.0 inch per second velocity for V 

will give, at the distance of 1385 ft., a modified scaled distance 

of: 

27.5 

NOTE: This scaled distance is for this shot only, in terms of 

a maximum of 1 inch per second velocity, at the 

structure of interest, at a distance of 1385 ft. It has 

to be recalculated for every other shot, dependent on 

the distance to the structure of interest, which in turn 

dictates the allowable velocity. 

Since the scaled distance formula: 

k 2 

Ds = D/W 

can also be rewritten as: 

W = (D/Ds) 2 

again, using this example's values for substitution, it can 

therefore be calculated that using the modified scaled distance, 

the maximum explosive charge weight per delay that could be 

detonated at 1385 ft. distance would be: 

2536 lbs. 

Using the Section 816.67(d)(3)(i) scaled distance regulation alone, at 1385 ft., a scaled distance of 55 would have been 

permitted, allowing a maximum explosive charge weight per delay of 

only: 

634 lbs. 

Obviously, this is only a hypothetical example, but the 

attenuation formula selected for the argument is not in any sense 

extraordinary. The increase in allowable charge weight, according 

to circumstances - and care in collecting the base data - may be 

less, even considerably less, but it could even be more. What this 

89 
Prediction and Control Methods 

example does try to illustrate, however, is that the potential to remove, or lighten the restrictive significant load on the operator is a very 

per 

one. From being restricted to no more than 634 lbs. 

operator 

delay to over 2500 lbs. per delay does not mean that the 

can design 

has to shoot 2500 lbs. per delay, but it does mean that he 

drilling 

his blast up to that charge weight per delay in terms of costs, optimum breakage, and blasting efficiency, rather than simply to comply with the regulations. 

Appendix 'A', between pages 135 and 149, contains a complete 

of 

computer program, written in BASIC, that will run on the majority small IBM and IBM compatible computers, from the IBM PCjr., through the PC to the AT. This program is designed specifically embody to 

all 

all the requirements of the OSMRE regulations, and to permit 

distance 

the necessary steps to be taken to prepare a modified scaled application Also to be submitted to the regulatory authority. included in this appendix is a reference to a general use regression analysis program that will permit complete and versatile 

OSMRE 

control of blasting vibrations, without specific reference to the regulations, and a similar, but simpler, hand calculator program, on pages 164 and 165. 

PREDICTIVE DATA: USAGE FOR COMPLIANCE \iiTII 

SECTION 816.67(d)(4)(i) - BLASTING LEVEL CHART - AND FOR GENERAL AND CRITICAL PREDICTIVE PURPOSES. 

For compliance, the collected data must be frequency responsive, as already discussed. While the basic techniques are 

predominant 

the same, the maximum permissible velocity is based on the frequency of the vibration, rather than on the distance alone. 

Let it be assumed that the data collection and regression analysis provided the same attenuation formula as in the previous example. Taking a critical, close distance example, for comparison 

ft., 

purposes, 

permitting 

let the distance from the blast to the structure be 275 

and 

a maximum of 1.25 inches per second under (2)(i), let it be assumed that in the case of the frequency responsive data, 

excess 

the 

of 

predominant frequencies at this short distance were in 30 Hz, allowing a maximum velocity under (4)(i) of 2 inches per second. 

Under (2)(i) the modified scaled distance would become 23.7, allowing a maximum explosive charge weight per delay of: 

134.6 lbs., at 275ft. 

still 

If 

monitor 

compliance were sought under (4)(i), while the operator must every shot for both velocity and frequency, the 

90 
Prediction and Control Methods 

scaled distance that could be used to design the next shot would be: 

1/1.51 

Ds = (149.2/2) = 17.4 

allowing, at 275 ft. distance: 

W = (275/17.4) 2 = 250 lbs. per delay. 

Again, using precisely the same attenuation formula, and only changing the method of compliance - the operator's option- it is clear that nearly twice the weight of explosive can be detonated! At close distances, under critical conditions, this kind of difference can truly be said to provide relief from restriction. Efficient and practical blasting methods can indeed be used at close distances, and the operator will remain in complete compliance with OSMRE regulations. Care must be exercised, however: though these calculations are based on the statistical probability of NOT exceeding 2.0 inches per second at a confidence level of 95%, and it is therefore likely that recorded vibrations will be well below this level, nevertheless IF a velocity in excess of 2.0 inches per second were recorded then the operator would be subject to a violation. 

Quite apart from considerations of compliance or not, these methods offer complete control and protection when: 

• Blasting has to be carried out within short 

distances of sensitive structures well within 

the perrni t area • 

• Allegations of blasting damage are made at 

locations, distant or close, where no vibration 

measurements had been made. The maximum possible effects can be accurately calculated. 

These methods and applications are discussed fully in Appendix 'A', together with examples of typical calculations. 

91 
CHAPTER 11 

FREX)UENCY CONSIDERATIONS 

It is important to be able to determine the frequency content 

of a ground vibration signal because the response of structures to 

blasting vibration is dependent on both particle velocity and 

frequency. Frequency is the number of oscillations per second that 

the ground surface vibrates as the seismic energy created by a 

blast passes by a particular location. Frequency is usually 

expressed in units called Hertz (Hz). (1 Hz = 1 oscillation per 

second.) 

A structure, like a tuning fork, will vibrate at a fundamental 

natural frequency when excited. The maxinn.nn response of a house to 

blasting vibration occurs when the frequency of the ground motion 

matches the natural frequency of the house. On the other hand, 

when there is a mismatch between the ground vibration frequency and 

the natural frequency of the house, very little energy is 

transmitted into the structure. 

This dependence on both particle velocity and frequency is the 

rationale for the OSMRE blast vibration regulations. Recent US 

Bureau of Mines research has determined that the fundamental 

natural frequency of low rise (1 or 2 story) residential structures 

is in a range of 3 to 12 Hz. These low frequencies are more 

predominant at greater distances from a blast, and this is the 

reason for the more restrictive particle velocity limit of 0.75 

inch per second at distances beyond 5001 ft. from the blast site. 

At close in distances, up to 300 ft. from a blast, high frequencies 

(above 40 Hz) predominate the vibration record. These higher 

frequencies are well above the fundamental natural frequencies of 

residential structure, so a higher particle velocity limit of 1.25 

inch per second is allowed. 

When the ground vibration frequencies can be shown to be higher 

than 30 Hz, then the blaster would be permitted a peak particle 

velocity of 2 inches per second regardless of the distance away 

from a blast, by using the Alternative Blasting Level Criteria 

shown in Figure 1 [Section 816.67(d)(4)(i)&(ii)], Figure 12 in this 

Manual, page 24. 

The Alternative Blasting Level Criteria permit the most 

accurate prediction of blast vibration effects, provide the best 

defense in the event of litigation and offer mininn.nn restrictions 

on blasting procedures and therefore, the optinn.nn . potential 

efficiency and cost savings, while still offering maxinn.nn 

protection to the homeowner. In order to be able to use these 

Alternative Blasting Level Criteria, it is necessary for the · explosives user to determine the frequency content of the blasting 

vibrations. 

93 
Frequency Considerations 

The frequencies present in a ground vibration seismogram are a 

result of three effects: the source, the geology of the travel path 

from the source to the seismograph, and the geology of the 

seismograph location. The blast frequency spectrum may be quite 

simple with the energy concentrated in one narrow frequency band. 

Such a condition would obtain at larger distances from a blast, 

when higher frequency components have been attenuated. Figure 41 

is an example of such a relatively simple waveform. As can be 

seen, it is only necessary to determine the time interval between 

two adjacent peaks in order to calculate the frequency. 

0 0.1 

PEAK PARTICLE VELOCITY= 0.35 IN/SEC 

0.2 0.3 0.4 0.5 

TIME (SEC) 

PERIOD= T= 0.054 SEC 

FREQUENCY= 1/T= 1/0.054= I 8 Hz 

Figure 41. 

0.6 

Calculation of frequency for a simple waveform. 

For such simple waveforms, the frequency can easily be 

determined by measuring the time required for one oscillation of 

the waveform. 

A more sophisticated method to determine the frequency content 

of a blast vibration recording would be a Fourier analysis. 

Because a blast vibration recording is not a continuous event, that 

is, it starts at a specified time and has a limited duration, it is 

called a discrete signal. In addition, the particle velocity 

levels are not necessarily periodic in that the peak values do not 

remain constant from one cycle to another, but vary, usually having 

the largest peaks early in the waveform and decreasing with time 

later in the waveform. As a result of having these properties, the 

Fourier transform will calculate only the relative amplitudes of 

the vibration frequencies contained in a waveform, but will not 

enable one to assign a peak particle velocity to any particular 

frequency. The plot of a Fourier amplitude spectrum normalized to 

the maximum peak particle velocity of the entire waveform can be 

used to estimate the particle velocity contributions for the 

various frequencies present. Such an estimate would be 

conservative, in that the overall waveform peak particle velocity 

94 
is a result 

present. This 

this chapter. 

Frequency Considerations 

of contributions from all the frequency components 

subject will be discussed in greater detail later in 

F""oncy (Hz) 

Figure 42. 

Fourier amplitude spectrum for a simple waveform. 

The plot of the Fourier amplitude spectrum for the simple 

waveform previously discussed is shown in Figure 42. It can easily 

be seen that the amplitude at 18 Hz predominates the spectrum. 

The overall peak particle velocity of the entire waveform was 0.35 

inches per second. For this specific particle velocity recording, 

the 0.35 inches per second can be assumed to be almost entirely 

composed of 18 Hz energy. 

A complex waveform results when two frequency components are 

present. These frequencies could represent the between hole and 

between row delay periods, or one frequency could be from the 

effects of soil thickness at the seismograph location, and the 

second frequency from a repetitive firing time in the blast design. 

LOW FREOlENCY ANALOG WAVEFORM 

HIGH FREC:U:NCY ANALOG WAVEFORM 

RESU..TANT ANALOG WAVEFORM 

Figure 43. 

Analog waveform with high and low frequency components. 

Figure 43 shows a waveform made up of a high frequency and a 

low frequency component. The particle velocity of the low 

95 
Frequency Considerations 

frequency component is twice that of the high frequency component. 

In this particular example, the particle velocity for each 

frequency component can be measured directly from the waveform. 

Figure 44 represents a more complex waveform which results when two 

frequency components are present, having equal particle velocities, 

but different phase relationships. It would not be possible to 

analyze this waveform by direct measurements, since the peak level 

is dependent on not only the particle velocity of each component 

but also on the phase relationship. 

0,35lnlsec 

.rV 

_,.-. .-·,, .... 

.,/ .......... 

. ' 

· ..... -

0.45lnlsec 

lQW FFIEOl£NCY ANALOG WAVEFORM 

HIGH FREQUENCY ANALOG WAVEFORM 

RESU..TANT ANALOG WAVEFORM 

Figure 44. 

Analog waveform with two frequencies 

showing the effect of phase relationships. 

~;~ l PEAK PARTICLE VELOCITY • 0,271n/sec 

II (\ (\ (\_/\(\,., Oo/\ !\ o <> V' 0 = <> c:. 

.1 0,2 ,3 

TIME (SEC) 

PERIOD: T1 ~ 0.053SEC FREQUENCY: F1~-1/T1 "i 1/0.053= 19 HZ 

PERIOD: T2: 0,027SEC FREQUENCY.= F2: 1fT2: 110.027., 38 HZ 

Figure 45. 

Calculation of frequency for a waveform 

with two predominant frequencies. 

96 
Frequency Considerations 

Figure 45 is an actual blast vibration record containing two 

frequency components. The period for one frequency is .053 seconds 

(19 Hz) and for the second frequency the period is .027 seconds (38 

Hz). Calculating the particle velocity for each of these 

frequencies is more difficult than for a simple wave having only 

one frequency present. 

One method of determining the particle velocity of each of the 

frequency components would be to filter the original waveform to 

pass only that frequency to which it is desired to assign a 

particle velocity. If the blast vibration waveform has been 

recorded on magnetic tape, then analog or digital filtering would 

be done to selectively pass those frequencies of interest. The 

waveform in Figure 44 has been filtered using digital methods to 

first pass only the 38 Hz component, and then to pass only the 19 

Hz component. These results are shown in Figure 46. The Fourier 

amplitude spectrum for this blast (Figure 47) shows similar 

results, in that the amplitude of each of the two frequencies are 

approximately equal. 

ORIGIN.-.L WAVEFORM 0.28 IN/SEC 

(\ (\ (\ f\..111\AQo(\ 1\ 

VVCAJ\)V V VV~ V~t:::J <::> <"")<:::::::> <> <:> C> 

38 HERTZ COMPONENT 0.15 IN/SEC 

> 1\ 0 I\ r\ 0 Q Q J"\. 1\ 1\ (\ 0 A 0 A a 7 0 (TO\) 0 0 VUVVV \TV V" 0 uc u 

19 HERTZ COMPONENT 0.16 IN/SEC 

CJ V\J v ...... v v v c> <:::> v c;; 

Figure 46. 

Results of digital filtering. 

FREQUENCY CHZJ 

Figure 47. 

Fourier amplitude spectrum for a waveform 

with two predominant frequencies. 

97 
Frequency Considerations 

An evl!n more complex waveform is shown in Figure 48. The Fourier amplitude spectrum shows three frequencies present: 8, 19 and 42 az. The results of digital filtering show the particle velocities associated with each frequency. 

ORIGINAL WAVEFORM 0.423 IN/SEC 

• • *Vll V V W'9J V vv crro..;o if v 'V e c:> 

8 HERTZ COMPONENT 

19 HERTZ COMPONENT 

n 041:;> " 0 0 

42 HERTZ COMPONENT 

0,107 IN/SEC 

0.138 IN/SEC 

avo- ;C;$00 

0.321 IN/SEC 

_f\0 01\ oft/\(\" cc/)0,., 0" vo 0 V 0 vv4JY • v o o 

FOURIER AMPLITUDE SPECTRA 

FREQUENCY (HZ) 

Figure 48. 

0 

a:::::::::> C5 == 

Analysis of blast vibration waveform 

with three frequency components. 

An alternative method to determine the frequency content of a waveform would be to calculate a response spectrum. These 

response spectra can be used to predict how structures will respond to blasting vibrations. A structure is defined as a single degree of freedCIII model having mass, stiffness and damping. The actual values of mass and stiffness need not be known, since the effect of both factors determine the system's natural frequency. The model needs only to be defined in terms of natural frequency and damping. Damping is a measure of the frictional loss of energy in the structure as it vibrates. The response spectrum, while it can 

98 
Frequency Considerations 

be used to determine the dominant frequencies 

motion, contains much useful information on 

responding. 

present in the ground 

how the structure is 

The response method calculates the maximum relative motion 

between the ground and a structure of a specific natural 

frequency. The range of structure natural frequencies for which 

this maximum relative motion has been calculated on Figure 49 is 3 

to 50 Hz. The response spectrum normalized to the maximum peak 

particle velocity can than be used to estimate the particle 

velocity contributions from the various frequency components. As 

can be seen on Figure 49, the normalized response spectrum gives 

conservative approximations of the peak particle velocities 

calculated by the use of digital filters. 

>-

>--

2.0 

C3 .2 

0 

_J 

"' > "' > . .0 ' 

;::: .o ... 0 

_J 

!l! " 

.04 

.02 

·" iS 

"' s:: .2-4 ~ 

:~~ N .17 , 

.15 ° .12 c: 

,097 '"'0 

.073 "' ~ 

-a .049 5; 

-i 

0 

r 

:gg "' <.020 , 

.017 b: .015 0 

.012 =i ,009 -< 

0 

.007 ~ 

"' "' .005 (") 

~ 

·"'--'---t-'-;l"c-..._.r_..-l,!r-...._...,,*,~'--;\,;-._r~--.lr-..._*_.___,,_.._ ..... oo, 

FREQUENCY (HZ) 

Figure 49. 

Response spectrum of a blast vibration waveform 

with three frequency components. 

Further information on this subject may be found in the 

Medearis report "The Development of Rational Damage Criteria for 

Low Rise Structures Subject to Blasting Vibrations", and in the 

Dowding report "Cracking and Construction Blasting". In addition 

99 
Frequency Considerations 

to these, the reader is referred to the two leading Bureau of Mines 

publications, RI 8485 and RI 8507, that deal specifically with 

frequency considerations. 

In concluding this chapter, it is appropriate to refer again to 

the preamble to the Rules and Regulations (Federal Register, Vol 

48, No. 46, Tuesday March 8, 1983) , where on page 9800: " OSM 

acknowledges that response spectra analysis as used in the RI 8507 

study (Siskind and others, 1980) and by vibration consultants 

provides a unique solution because it sets allowable limits 

accurately by predicting the range of potential damage This 

technique if applied on a case by case basis might prove to be the 

best substantiation of the actual damage range. In order to allow 

such technique, and to provide operators the option to increase 

velocities above the maximum limits set for general compliance, OSM 

has included in Section 816.67(d)(4) an alternative method using Figure 1." 

100 
CHAPTER 12 

RECORD KEEPING 

Records should always be made by a responsible person at the 

time of the event. This responsible person should be, or be 

delegated by, the certified blaster, under whose direction all 

blasting must be conducted. A blaster is required to be present at 

all shots, together with at least one other person [Section 816.61(c)(3)]. 

It goes without saying that a blast vibration seismogram alone, 

unsupported by adequate records, is virtually useless. Even when 

the instrument itself can be programmed to record the date and time 

automatically, or when the sound channel possesses a 'VOICE' 

function to permit verbal comments and information to be recorded 

on the magnetic tape together with the blast, seismograph records 

must be supported by proper written records. 

All blasting operations, whether or not they are subject to any regulations, must always be fully documented. This is quite apart from any consideration of compliance with OSMRE regulations. It is 

simple common sense to insist on a complete record keeping program wherever and whenever explosives are concerned. The risk of 

litigation is very real, and this risk alone should convince 

operators that good, clear, and complete records are essential. In 

the event of litigation, they are certain to be called into 

evidence; and as evidence they should be absolutely unassailable. 

OSMRE regulations, in fact, establish a minimum standard for 

what should be regarded as the essentials of adequate blast and 

vibration records (Section 816.68): 

• They must be kept at least 3 years. It is wise to 

keep them for much longer. 

• They must contain the name of the operator conducting the blast. 

• They must include the location, date and time of the blast. 

• They must be signed by the certified blaster conducting the 

blast, and show his or her name and certification number. 

• They must identify the nearest dwelling, public building, school, church, community or institutional building outside 

the permit area (except those described in Section 

816.67(e)) and establish the direction and distance from 

the nearest blast hole to that nearest structure. 

101 
Record Keeping 

o They must note weather conditions, including those which 

may cause possible adverse blasting effects. 

o They must record the type of material blasted. 

o They must incorporate sketches of the blast pattern, including number of holes, burden, spacing, decks 

and delay pattern. 

o They must specify the diameter and depth of holes, and the type and length of stemming. 

o They must record the types of explosives used, the total 

weight of explosive used per hole, and the maximum weight of explosives detonated in any one 8 millisecond period. 

o They must specify the initiation system. 

o They must provide details of mats or other 

protections used. 

These details must always be provided for any irrespective of whether or not vibration monitoring is 

place. 

blast, 

to take 

If vibration monitoring is required by OSMRE regulations, then 

the following information must also be included in the records: 

o Type of instrument; sensitivity (or "range setting") and calibration signal or certification of annual 

calibration. 

o Exact location of instrument, and the date, time and 

distance from the blast. 

o Name of the person and firm (can be the operator) taking the reading. 

o Name of the person and firm (can be the operator) analyzing the seismographic record. 

o The vibration level and/or airblast recorded. 

The above vibration monitoring records are also the minimum 

necessary to support any seismogram or airblast recording, even if 

monitoring is not required by regulation. If monitoring is carried 

out, for whatever reason, it cannot be over emphasized that proper records must be kept. Attempts have been made in the past to 

reconstruct "blast records" from explosives supply invoices, and to 

develop support for seismograms from memory. Such poor record 

102 
Record Keeping 

keeping must never be tolerated. In 

absence of such documentation places 

precarious position. 

the event of 

a defendant 

litigation, the 

in an extremely 

One point that sometimes causes a certain amount of confusion, 

and that can lead to argument, is the "shot to structure or 

instrument" distance. The regulations require recording the 

direction and distance from the nearest blast hole to the nearest 

structure. From the point of view of vibration data collection and 

vibration prediction, where the scaled distance is the basic 

criterion, it is important to measure the distance from the center 

of the group or row of holes that represent the maximum charge 

weight per 8 ms delay. It may be that two or more groups of holes 

having similar charge weights per delay may have to be considered. 

In that event, the distance recorded would be that distance - and 

charge weight per delay - that resulted in the lowest scaled 

distance. In most cases, only academic differences will be 

observed; but in case significant differences do appear, both 

distances should be recorded and identified: --

REPORT OF BLASTING OPERATION County: ___ Twp: ___ _ 

State: ---------

Permit: ____ Mine ID# __ _ 

(Military) 

Today's Date ____ Time of blaot: ____ (Time ) Location of blast: _______________ _ 

Supervisor, in-charge of blast: Name: _______ Signature: ____________ ,Lic.~llioo'"'oo;c,-;;roo,Cl>7.udeT 

Collllll<!rcial or (Company Owned or) 

Distance for 01 nurest hole to: (Circle one) Dwelling, School, Church, Institutional bldg.: ______ ft.{Leaaecl Property) 

Dir.-ction to property: N S E W Weather Conditions at titne of blast: ( ) Cloudy __ , Clear __ , Partial Overcase• ___ _ 

Temp. __ , Barometric Reading __ , Wind Description _____ ,Remarks _______________ _ 

Material blasted:() Overburden __ , Part1ng __ , Other __ Explain•-----------------

Total number of holes shot: ___ Burden ___ ft. Spacing ___ h, 

Depth of holes: From: ____ ft TO ____ ft. Diameter of holes: ______ inches. 

Type of explosives used ) AN-FO-Bagged Bulk __ , Other Exphin'cc--,_-------------

----:r;;t"at weight of 

_______________________ E,xplosives used: ______ ll Decking: 'ies No 

Max. pound• detonated within any 8 ms period: ___ // Max. number of holes detonated with any 8ms period: ____ _ 

Method of d"tonation:() Nonel __ , Electric cap __ , Other __ , Explain ______________ _ 

Type of circuit used:( ) Series __ , Pat"allo!.l __ , Nonel __ , Other __ Explain ____________ _ 

Stetrming information: Type used: _____ ,Depth: ____ ft., Was protective cover <.tsed? Yes No 

Type of dellty detonator used: ________ . Minimum delay periods _______ ,millisecond. 

Distance from nearest hole to seistector: ft. Exact location of seistector: __________ _ 

Name of mine personnel servicing seistector: {print) _______________________ _ 

.. 

. " " .. . .. 

..0 lt"1: 0 0 ... .. 

... " .. .... 

Name of firm analyzing seistector print-outs=----------------------

Name of person analyzing print-out•=-------------------------

Seistector reading of this blast: _________________________ _ 

Figure 50. 

Typical blast record form. 

103 
Record Keeping 

HASTING ""POH 

Mi~ ________ Pit MQ·-------""1•1• uood -----

________ Dri!l 

Ti• ________ rotte<n ------'-"a<l in uood -----

Ori\lu _______ No_ Of Holoo -----

Sltaotor ------- Holo Dio. ------ S~ift 

Holpor -------

HOLI!S SHOT 

~--~--~--•w __ •~-- I 

HOLES SHOT 

~·--•~ __ w•------~ 

. . . . . 

II 

Figure 51. 

Blasting report (1). 

OUUI.C llfOU 

"'"' .......... DO<o .. Ill 

··- Loodlooood 

Orlllo< ..... , .. ! .. 

·-· .. l!olo o\o. Sill" 

...... 

IIDIZJIIIOt 

- --- --- --.- ··--

Figure 52. 

Blasting report (2). 

104 
Record Keeping 

Figure 50, on page 103, shows a typical blast record form that 

provides the operator with an efficient and complete record of each 

event. It can include seismograph records, and can be used in 

conjunction with Figures 51 and 52, opposite, to provide sketches 

of the blast and delay pattern. 

Figure 53, below, shows a representative blast and seismograph 

analysis form, as provided by a consultant for use with his 

instrumentation. Figure 54, on page 106 shows another example of 

this, with a slightly different format. In this case, the form is 

provided with carbon copies which may be retained with the 

operators blast records. 

VIBRA·TECH BLAST AND SEISMOGRAPH ANALYSIS 

ComJHny ----------- Operllton: Name------------Calli CJ Quarry CJ Constr_ 0 

State Other------

------------------------------BUST DATA--------------------------- snotNo __ Elurden __ rt Tot.IIE•ptosi~es __ tbs Ma• Explo/Detay __ tbs Delay Nos -====== Date S~ctng -- h __ lbs Max Holes/Delay Delay Mlr _ 

Tome Ooameter __ fo __ lbs Cost Nearest Bldg ___ It No of Timer Corcur~ __ _ 

No Holes __ Stemmtng __ h __ lbs O~r Nearest Bldg m• 

Depth __ fl Stem. Ty~ -- __ tbs WeatMer Blaster 

Euct Blast Location _ Blasters Comments 

SEISMOGA.A.PH DATA Euct Locat•on of~o~••~• ~~:~:~~~~~::~~~~~~~~~=~~0~"~' ~To~S~•~,.~~~~~h~ Seos No __ Cassette No Opll!rltor Meter:: (Partocle Veloc•ty ___ '" 

Fla,.,ge ------ ops Trogger Level ---ops Wtlness A or Overpressure __ OBo 

:':,,.:"",7.,.:7'.,:::":7'""7.,.7.,.:::":7', ----------------VIBRATION MEASUREMENTS <"o•··••• •oc~ ,., 0 ..,_, 

Transverse __ on'sec 

Ver!•CII .nlse<: 

Peak Ground Vobratoon •s (l•dnon) (on ueess of} 

Pelk Aor Overpressure os lwothon) (on e~cess Ql) 

Longotudonal __ in/sec Analyst's Rematks 

Figure 53. 

Anatys•s By 

11moror 

hmotol 

Typical blast and seismograph record form (1). 

on.'sec 

Pre-blast and post-blast 

documentation. Whether the 

surveys also need very careful record 

initial survey employs written or tape 
Record Keeping 

recorded notes, it is essential that complete contemporaneous 

records be kept that will: 

• Identify the property, property owner, and date and 

time of the survey. 

• Identify the person making the survey, and the operator. 

• Determine the condition of the structure, document any 

pre-existing defects and positively relate any 

photographic or separate tape records to the body of 

the report. (Figure 55 shows typical pre-blast 

inspection forms that can be employed for the written 

methods of defect recording.) 

• Assign identification numbers to all photographic 

negatives as they are exposed, retaining these numbers 

through to the final report. Any unused, or spoiled 

frames should be explained. 

• Identify particularly historic or fragile buildings 

or specially valuable and fragile contents that 

might be particularly vulnerable to blast vibrations, as 

discussed in this Manual on page 9, and as required under 

Section 850.13(b)(lO)(iii). 

Recording ,, ______ Client: _________ Job Location: __ _ 

Reported By: ---------Tltle: _____ Sels.ll _______ Cameral• __ _ 

Date 

Time 

No.ot Holes 

Max. 1/Delay 

Tote! Chg. 

Olatance 

BLAST DATA 

Location of shot point _______ _ 

Comments-----------

SEISMIC DATA. 

Sets. Range 0.25 1.0 .4.0 (circle uttlng) 

Digital Readout: 

l ___ _ 

v ___ _ 

T ___ _ 

"----

F:>n USE BY VME ONLY 

l 

v ___ _ 

T ___ _ 

"----

Sound __ _ 

Test Location _____ ~:::S~c:•':·-=======D _ 

=FO::R~V=M=E~U=SE:_O::N:l::_Y::_::R:EPO:::RT::_E:D:_:B>_:Y~: ====-'D=A~TE~':::--===~C::O:MMENTS: 

Figure 54. 

Typical blast and seismograph record form (2). 
·~· 

·~· 

Record Keeping 

I 

I 

·~· 

DATa: 

11001* 

............,IDn,po•-""'11 

Olf..-DTOIIGOI C 

... _ ~--·.:.·-------.. - .. --·- __ .. ___ ... _ ..... _ 

" _C'OII _____ _ 

·" 

Figure 55. 

-·-

.... -·--·--

00 --0 

IOI' .... UIUOCI' VIII. 

YUC ~0 

...... o...-noouu -----

f-----

--0 -c -

c ___ c c c 

1---" c c 

-c ~c 

CAC-fiT ·--·--- , __ .. __ 

Typical pre-blast inspection forms. 

107 
CHAPTER 13 

CITIZEN INTERESTS: RIQITS, PROTECTION AND INFORMATION 

This section of the OSMRE Blasting Guidance Manual is 

specifically directed to the Citizen, whose safety and property are 

protected by the OS~ffiE regulations. All the other sections are for 

the information and guidance of the Mine Operator, so that he may 

properly comply with the requirements of the regulations, and 

therefore ensure the safety of the citizen's person and property. 

This section will provide the citizen w~th information on his 

rights under the law, how the regulations will protect and assist 

him, where he may go to obtain protection, and information on just 

what to expect in terms of perceived blasting effects, and what to 

look for when blast vibration damage is suspected. 

RIQITS AND PROTECTIONS UNDER OSMRE REGULATIONS 

LONG TEP~I: Initially, before a mine is permitted, the citizen 

is free to exercise the most powerful right that he has, during the 

actual permd.tting process, to express any objections he may have to 

the mine being there in the first place. Since this manual is to 

guide those involved in an existing m.ine, miners or citizens, the 

premise will be made that the mine has been permitted, and is, or 

shortly will be, in operation. 

The citizen is assured that public or private lands which are 

subject to surface mining will be reclaimed and returned to 

substantially the same form and condition as they were prior to the 

nunlng operation. Obviously, the time element involved will be long 

term, since many mines will have "lives" of ten, fifteen, or twenty 

years, and even longer in some cases. The State Regulatory 

Authority or OSMRE will be able to advise on the projected length 

of time that any mine is planned to remain in operation. 

When mined land is reclaimed, the law requires that the 

original contours are restored to as practical an extent as 

possible, that the original water courses, and availability of 

surface and ·ground water, are not changed, inside or outside the 

permit area. Local features and wildlife habitat such as rocky 

outcrops have to be restored in a reasonable manner, while topsoil 

must be replaced and vegetation must be reseeded. That these 

regulations are in fact proving both practical and effective can be 

evidenced by a visit to virtually any modern surface coal mine, 

particularly in the Western grasslands. The public are frequently 

unaware that the land that they are viewing has already been mined 

through and reclaimed: at first glance it is frequently taken for 

virgin, unmined land. 

109 
Citizen Interests 

SHORT TERM: The law also provides protection for the citizen 

from the short term effects of surface coal mining. These short 

term effects largely derive from the "adverse effects" of blasting 

that are specifically addressed, to the mine operator, in Chapter 3 

of this Manual. Although the long term effects and protections 

mentioned on the preceding page refer to permitting, reclamation 

and non-blast considerations that are strictly outside the scope of 

this Manual, the short term effects - generally from blasting - are 

very much within its scope, and are therefore discussed in detail 

for the benefit of, and better understanding by, the citizen. From 

the citizen's point of view - understandably sometimes somewhat 

different from that of the mine operator - the protection provided 

by the regulations can be summarized as follows: 

• The prevention of injury to persons. 

• The prevention of damage to private property 

outside the Permit Area. 

• The prevention of damage to public property 

outside the Permit Area. 

The citizen will notice, however, that this does not provide 

any real degree of protection against annoyance. This is 

understood, and this particular point will be discussed - hopefully 

to the citizen's satisfaction- later in this chapter. 

THE PREVENTION OF INJURY TO PERSONS 

Explosives themselves are a great deal safer to use and to 

handle than most people generally imagine. This is not to say that 

explosives are not potentially dangerous: of course they are, and 

they should only be used by experienced and trained personnel, 

working under the supervision of a Certificated Blaster. Dynamite 

is now very little used in production blasting anymore except as a 

"primer" to detonate or initiate the main charge, most probably a 

"blasting agent" rather than a "high explosive". A stick of 

dynamite, however it might be portrayed in an adventure movie, is 

in fact considerably safer to handle than is a gallon can of 

gasoline! The main risk that might be incurred from handling 

dynamite, particularly with bare hands on a hot day, would be to 

develop a very severe headache, due to absorption of 

nitro-glycerine through the skin! Accidents can happen, however, 

and it is for that reason, amongst others, that OSMRE demands 

proper experience and training. The citizen will not be exposed to 

this risk, of course, and therefore the only possible way in which 

personal injury could result would be from "flyrock". 

Flyrock and the dangers attendant to it are described in 

Chapters 3 and 4, pages 20 and 21, and 30 and 31. Flyrock can even 

cause death, and therefore the regulations take this hazard very 

110 
Citizen Interests 

seriously indeed, as it is without doubt the most dangerous single 

adverse effect of blasting. 

Having established that, how do the regulations protect the 

citizen? Since there is no practical way to guarantee that flyrock 

will never occur - some "fly" or "throw" is actually normal to most 

blasting operations, and blasting mats or dirt cover have to be 

used for maximum control - the obvious way to eliminate the danger 

is to prevent flyrock from occurring where people can be present, 

or to prevent people from being where flyrock might present a 

danger. The regulations therefore mandate that flyrock must travel 

no more them half the distance to the nearest occupied dwelling or 

other structure, beyond the posted blasting control area, or beyond 

the permit boundary. This is also the fundamental reason why 

unauthorized persons are not permitted to be inside these areas. 

Any citizen who is threatened by flyrock outside these areas 

has immediate cause for reporting a violation of regulations. 

It would be difficUlt to imagine how the other two adverse 

effects of blasting, ground motion and air blast, cotild cause 

personal injury under any normal circumstances, certainly to any 

person who was not a member of a blasting crew, and when an 

accidental detonation did not take place. From the viewpoint of the 

citizen, it is reasonable to assert that the only risks presented 

by these effects wotild be to property. 

THE PREVENTION OF DAMAGE TO PROPERTY 

Without question, the most common single cause of damage to 

property resUlting from blasting operations is due to flyrock. 

Obviously, the regulations to protect the citizen from injury will 

also protect his property from damage, and shoUld damage occur from 

flyrock, it is also evidence of a violation of the regulations. The 

evidence is also virtually indisputable, except, as noted on Page 

31, in the case of windshield glass breakage, or hail damage to 

vehicles. 

While ground motion, or vibration, is the second most common 

cause of damage, it is nevertheless only truthfUl to point out that 

actual damage due to blast vibrations is in fact quite rare. This 

is mentioned as much to stress the very carefUl and conservative 

nature of the OSMRE regulations on vibration limitations, them to 

defend the mine operator. 

These limitations, shown on pages 22-25 of this manual, allow 

under some circumstances up to 2.0 inches per second particle 

velocity, and under others as low as 0.2 inches per second, because 

of the different damage effects of ground motion of varying 

frequencies. This also explains the apparent anomaly of permitting 

higher velocities at short distances, because the frequencies of 

111 
Citizen Interests 

ground motion are higher at short distances, and higher frequency 

vibrationa have been found to be less damaging. Although the Bureau 

of Mines research which forms much of the basis for the OSMRE 

regulations has shown that there is a possibility of minor damage 

at velocities even slightly below 1.0 inch per second, in normal 

conditions, with properly constructed buildings, damage is unlikely 

to appear at velocities under 3.0 inches per second. IVhenever 

damage is referred to in this context, it is also necessary to 

remember that minor, threshold, cosmetic damage is what is meant. 

(See Chapter 4, page 29.) When major, structural damage, such as 

the collapse of brickwork, extensive and serious cracking 

threatening structural integrity, or concrete cracking is found 

(apart from the small drying-out or temperature cracks to be found 

in virtually all concrete) then either the ground motion exceeded 3 

or 4 inches per second, or some other reason exists for the damage. 

See "CAUSES OF STRUCTURAL DEFECTS" on pages 4 to 6 of this manusl. 

If an operator is in compliance with the regulations, the 

citizen's house will be effectively protected from damage, even 

when the blasting vibrations are repeated on a daily basis over a 

period of years. It is a relatively simple thing to check on 

whether an operator is in compliance, and that is by measuring - or 

"monitoring" the vibrations over a period of time. Many mine 

operators own or rent monitoring instnnnents, and most will readily 

accede to a request from a householder to monitor vibrations in 

this wa)'· Blast vibration consultants, too, will be happy to carry 

out this service, either in person,· or simply by means of an 

instrument rental for a short period. Most available instruments 

are very easy to use, and are quite impartial: they will accurately 

report a vibration level regardless of who owns them, or who 

switches them on! 

If velocities in excess of the regulatory levels are recorded, 

then regardless of the method of regulatory compliance that the 

operator has chosen (See Chapter 9, page 73), it will be apparent 

that the operator is in violation of the regulations. This is 

because the "scaled distance" option is so safe and conservative 

that it is almost impossible to exceed regulatory vibration levels 

when it is used. In any case, should this situation arise, 

subsequent seismic tests would be able to establish this 

possibility. If the operator is using one of the velocity 

limitation options, then there would be no question at all. 

Where airblast is concerned, although this is the effect that 

causes the most annoyance of all, it is also the effect that causes 

the least damage. Airblast that can cause even minor damage is so 

much higher - some 10 to 15 times higher - than the maximum allowed 

under the OSMRE regulations, that it can virtually be discounted as 

a possible cause of damage. In any event, whenever airblast does 

cause damage, it always shows up first as broken window panes. If a 

building suffers structural damage, and it does not have any broken 

windows, then the cause was other than airblast. 

112 
Citizen Interests 

This, then, is one area of the regulations where annoyance plays as much a part in the thinking behind the regulations as does 

damage. It does not totally eliminate the problem, but it does 

bring it within reasonable bounds. Airblast can be monitored, in 

the same way as ground motion, and if an airblast level is measured 

at an occupied dwelling that is in excess of the regulatory limits, 

then the mine operator is in violation of the regulations. 

In fairness to the operator, it might also be stated that 

airblast is the most difficult of all the adverse effects of 

blasting to control, because of the many weather and atmospheric variables, and other factors outside the control of the mine 

operator. OSMRE does not of course condone at any time any breach 

of the regulations, and any such recorded breaches·constitute 

violations regardless of the circumstances. OSMRE does however 

concede that an occasional airblast violation does not 

automatically indicate unwillingness to comply on the part of the 

operator. 

PRE-BLAST SURVEYS 

The OSMRE regulations are quite clear and specific on the 

rights of the citizen when it comes to the question of pre-blast 

surveys. Sections 816.62 (a), (b), & (c) require that a mine 

operator notify all residents living within a half mile radius of 

the mine permi~area, at least thirty days before the blasting 

program is to begin, on how to request a pre-blast survey. The 

resident, or the owner of the property, may request that such a 

survey of his home be carried out, and this request may be made 

either to the mine operator, or to the regulatory authority. The 

mine operator may carry out the survey, or he may employ others to 

do this on his behalf. If he employs a third party in this way, that person is likely to be a professional consultant who is 

experienced in this type of survey. In either event, it will be 

carried out at no charge to the resident or owner of the property. The survey nrust be prompt, and the report of the survey, a copy of 

which must be supplied to the person requesting the survey, must 

also be prompt. If the resident or owner disagrees with the content 

of the survey, a detailed description of the areas of disagreement 

may be submitted to both the operator and the Regulatory Authority. 

Updated reports of any additions, modifications or renovations 

mu3t also be surveyed and provided by the operator to the resident 

or owner, if requested. 

The pre-blast survey provides one of the most powerful protections and controls that it is possible to have on the often 

argued question of damage liability. A householder may be certain 

in his own mind that a particular crack or defect is the direct 

result of blasting activity at the neighboring mine. If a pre-blast 

survey does not record such damage, and inspection and 

113 
Citizen Interests 

investigaticn of his complaint shows the defect to be there, then 

there can be no further argument. Note that in this case the 

purpose of the survey is not to detennine whether the operator is 

in violation of the regulations or not. The operator is in 

compliance with the regulations, merely by carrying out the surveys 

as required. The survey itself simply detennines whether any 

subsequent damage complaints are actually damage or not: obviously, 

if the determination is that the damage was caused by the blasting 

operation, then it is the operator's responsibility to repair or 

recompense the householder for that damage. OSMRE, however, cannot 

compel a mine operator to repair or recompense the householder. 

RestHution is often a legal matter. 

The pre-blast survey also protects the mine operator from 

unjustified damage claims. Whatever defects are recorded prior to a 

blasting program cannot subsequently be claimed as blast vibration 

damage. A resident or owner does not have to submit to or request a 

preblast survey, but if he declines such a service it might well 

weaken any subsequent claim he might then make for damage he claims 

was suffered due to that blasting. 

BLASTING TI~ffiS AND SCHEDULES 

Another protection provided to the citizen by the OSMRE 

regulations is the requirement that blasting take place in 

accordance with published schedules, and within specified hours. 

Blasting schedules must be published in a local newspaper at least 

ten days, but not more than thirty days, before the start of a 

blasting program. Copies of the schedule must be distributed to 

local governments and public utilities, as well as to all local 

residents within a half mile of the blasting site as described in 

the schedule. The operator must republish and redistribute the 

schedule at least every 12 months, at least ten days but not more 

than thirty days before blasting, whenever the schedule area or 

blasting times differ significantly from the previous information. 

All blasting must take place during daylight hours unless more 

restrictive times are specified. If night-time blasting is approved 

by the regulatory authority, it must be based on evidence from the 

operator that the public ''ill be protected fror:1 adverse noise and 

other ir:lpacts. 

All other unscheduled or night-time blasts can only be 

conducted on an emergency basis, for reasons of operator or public 

health or safety. In such a case, the operator must notify all 

residents within half a mile by audible signals, and he &ust 

document the reasons for, and conditions of, the unscheduled blast. 

A typical example of such an unscheduled blast might be that the 

operator had loaded a shot, but had to vacate the area for safety 

reasons, say due to a thunderstorm. If night had fallen before the 

thunderstorm had ceased to threaten, and the operator felt that it 

114 
Citizen Interests 

was an unacceptable hazard to leave the loaded shot overnight, then 

he would be justified in carrying out the unscheduled blast, 

provided of course that he made notification of the blast and 

documented it properly, as required by the OSMRE regulations. 

PERCEIVED BLAST VIBRATION EFFECTS 

Thus far in this chapter vibration intensities have been 

referred to, unavoidably, in tG!rms of "particle velocity". 

Normally, when a member of the public hears someone - mine 

operator, government official or consultant speak of vibrations 

in unintelligible language - "point six five inches per second" - he cannot help but consider that it is just so much "gobbledygook'" 

and that perhaps the "experts" are even trying to hide things from 

him. Why can't they speak in terms that everyone understands? 

Unfortunately, no-one has yet invented terms for this rather 

specialized field that everyone does understand. 

What can be done in this chapter, however, that may at least 

alleviate this problem, is to discuss in simple everyday terms the 

way that human beings feel or perceive blasting vibrations. 

First, there is no doubt at all that some people can feel 

vibrations almost as low as instruments can measure them. It is 

often commented that human senses are very dull compared to those 

of animals, though it is not often realized how keen in fact some 

of these human senses are! The sense of touch, for instance. 

Stretch a hUl'lan hair across a smooth surface, or overlap t•,;o thin 

sheets of paper, and nu1 a finger across, and few people will have 

any problB~ at all in feeling just two or three thousandths of an 

inch! Although many people these days - especially the young - have 

reduced hearing ability, the hun~n body as a whole is astonishingly 

sensitive to ground vibrations. Levels can be felt that present 

absolutely no danger at all to structures. In fact, houses are 

vibrating much of the time to one extent or another. People, 

particularly heavy ones, or active children, generate motion that 

at times approaches or even exceeds - the limits set by OSMRE. 

Climbing or descending stairs, jumping, door slamming or even just 

walking across a floor can cause considerable motion in a 

structure. The fact is that 1~en people themselves are in motion, 

they do not notice any movement in the structure of their homes. 

So how do most people react to, and actually feel blast 

vibrations? The most obvious effect is usually the airblast. Since 

it does not always contain frequencies that humans can best hear, 

it is not always a very loud event. It is usually perceived as 

anything from a dull thUl'lp to a loud bang. A loud bang is not 

always a "high" airblast, and conversely, a dull thump may in fact 

be one. It might even be inaudible! The house may well react, or 

respond, the structure may creak, the windows may rattle, and, if a 

person is not expecting it, it may be quite startling. It is most 

unlikely ever to cause damage. 

115 
Citizen Interests 

Ground motion, or ground vibration, can be experienced in 

different ways. A very low frequency vibration, such as might be 

experienced from a large blast on a mine a long way off, might not 

be recognized as a vibration, only as sense of unease, or even a 

passing feeling of slight giddiness. Kigher frequency and highe+ 

intensity motion is much more obvious and recognizable, 

particularly if the structure responds. Humans are frequently 

disturbed by vibration levels that are perfectly permissible under 

the OSMRE regulations. This is discussed in the manual under the 

heading of "HUMAN SUBJECTIVE TOLERANCE" in Chapter 5, pages 35, 36 

and 37. 

When vibration levels occur which approach or exceed the 

regulation limitations, there is no doubt at all that most people 

find this unpleasant, and their cause for alarm is normally quite 

justified. It is the reason why most consultants advise their 

clients to try to keep well below the regulatory levels, and only 

plan to risk approaching them 1vhen blasting in those locations must 

be carried out. 

A common complaint involves the rattling of crockery. yfuen a 

person is at rest in his home, and the vibration from a nearby mine 

blast causes the crockery to rattle, then he is disturbed by this, 

and frequently worries about whether such a vibration could have 

caused any damage to his home. In investigating such complaints, 

however, it is sometimes noticeable that the crockery rattles 

simply when a person walks across the floor. When this is pointed 

out, it may be that that person, in motion, just did not realize 

that this was happening. Sometimes, though, the person admits that 

knowing that the rattling is due to a normal household activity is 

not worrying, but 1vhen it happens due to action of explosives, then 

who knows what that might have done! 

Apart from the normal activity of the occupants, a structure is 

subjected to daily, seasonal and incidental outside causes of 

motion. Some are very sHght, and unnoticeable to the casual 

observer, such as daily and seasonal temperature changes. The 

structure, however, is nevertheless affected by such temperature, 

and therefore dimensional, changes. Seasonal Qoisture differences 

can cause the ground the house is built on to expand and contract. 

More obvious causes of structural movement are high winds, 

thunderstorQs, and earthquakes. Nearby highways or railroads, ru1d 

of course airports, can all cause vibrations. 

Even unoccupied dwellings, if left undisturbed, will eventually 

deteriorate to the point of collapse. 

ACTUAL BLAST VIBPJ\TION EFFECTS 

One very important consideration concerns the response of a 

structure to a blast vibration. This has already been referred to 

116 
Citizen Interests 

briefly above. Rather like the wine glass that was shattered by the 

opera singer holding a sustained note, a structure has a "natural" 

frequency at which it will vibrate when "excited". lfuen an incoming 

gro\ll1d motion is at that same natural frequency, then the structure 

is "excited", and the resulting response can well exceed the 

intensity of the incoming ground motion. This again is the reason 

why the regulations permit higher vibrations at high frequencies 

than they do at low frequencies. Because of this also, since this 

phenomenon has already been taken into accolll1t, the regulations 

control the incoming ground motion only. From the point of view of 

perception, therefore, a person will be less disturbed by a blast 

when he is outside his house than 1vhen he is inside it. From the 

viewpoint of actual effects, hmvever, the citizen may well have 

noticed the potted plants on his window sill vibrate, and he nay 

consider it reasonable to req11est that vibration measurements be 

taken on the window sill. The mine operator would be justified in 

declining that request, as it would only measure the response of 

the structure at that point, and not be a valid measurement of 

gro\ll1d motion \ll1der the OSMRE regulations. 

lfuen frequencies are very low, about L, to 12 Hz, and structures 

respond, then the maximum danger of actual damage occurring exists. 

A small possibility exists of damage at velocities even below 1.0 

inch per second, which accounts for the low velocities allowed on 

the Blasting Level Chart, Figure 12 on page 24 of this manual. As 

frequencies increase, the likelihood of structural response 

decreases, and the allowable limits increase. The actual effect of 

a ground vibration close to, but not exceeding 2.0 inches per 

second, at a frequency at or above 30 Hz would be a highly 

perceptible vibration, and probably a very annoying one, but one 

that would not cause damage. 

Incidentally, ground motion has to be far above these levels to 

threaten wells or aquifers, although these problems are frequently 

feared and complained of. 

ANNOYANCE 

The above discussion on perceived and acttilll vibration effects 

has had the central theme of annoyance running through it. 

Unfortunately, annoyance is very difficult to quantify, and it is 

further complicated by the fact that not all human beings are 

annoyed by the same things. Some of us simply do not 1>•orry about 

things that drive others crazy. It can also help to recognize that 

as far as a local surface mine is concerned, the citizen who 

originally tended to benefit from the operation, and who did not 

oppose the application, will be far less annoyed by the operation 

than the citizen who did oppose that operation, and 1>•ho had to 

watch it become an established operation in the face of his 

objections. 

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Citizen Interests 

For those who do find that they are rul!loyed by surface mining, 

and cannot help .but be rul!loyed by surface mining, the following is 

a sincere discussion that they will hopefully find of some 

consolation, and that may even lead the way to a reconciliation 

with that rul!loyance. 

Certainly as far as the the airblast limitations are concerned, 

annoyance was very definitely considered when the regulations were 

written. The airolast allowed by OSMRE is less than half the level 

allowed by OSHA for impulsive noise. Except in emergencies, or when ~pecifically approved by the Regulatory Authority, as already 

discussed, no blasting is allowed at night, and the published 

schedules and notification system ensure that people are not taken 

by s~prise or startled by the blasting. 

Ground vibration presents a rather more difficult problem where 

rul!loyance is concerned, since humans are so sensitive, and can 

perceive - and be rul!loyed by - remarkably low, though certainly not 

damaging, levels of vibration. In order that explosives be used 

efficiently as a tool for breaking rock, it is sometimes necessary 

to generate vibrations that not only can be distinctly felt, but 

that some people might find find highly ffil!loying. These can be 

perfectly legal levels, within OSMRE regulatory limits, and quite 

safe, presenting absolutely no risk of damage. Nevertheless, for 

many people, they can, and do, ffil!loy. 

A possible solution to the problem lies in efforts to establish 

and maintain good relations between the citizen and the 1nine 

operator. It is normal, of course, for the operator to promote such 

relations, but in order for the maximum mutual benefit to be 

derived from such efforts, the citizen should attempt to extend his 

own hand no matter how difficult this may at first seem to be. An 

unbiased attempt to achieve mutual understanding is often a good 

first step. 

Understanding that the viei'Point of the operator is going to be 

significantly different than that of the citizen, and that this 

does not automatically signify an adversary situation, is a 

considerable step towards achieving good mine operator and citizen 

relations. Whereas it is sometimes the case that the citizen feels 

forced into an adversary situation by the mine, it can be that the 

mine, or at least some of its personnel, can feel precisely the 

same pressures. While the citizen feels that the mine threatens his 

peace, his environment, his residence, and his quality of life, the 

mine personnel qm also feel threatened by citizen complaints, 1~ch seem to jeopardize their very livelihoods. If the accounts 

that they make of the same situation might be widely disparate, and 

would seem to prove that one or the other just cannot be telling 

the truth, patience and understanding may well show that this is 

not the case: both are being entirely truthful by their own lights. 

118 

. I 
Citizen Interests 

Witness the blaster who tells the consultant arriving at the 

blasting site: "Those people on top of the hill! They're giving me 

fits! I've told them that there is nothing to worry about, but they 

complain every time I shoot! You will have to do something about 

them!" 

The consultant sets up his instrument at thej_r house, and finds 

that they are quite nice people, but rather afraid of the blasting. 

There is nothing strange about that. 

They say to the consultant: "That dyoamiting is getting on our 

nerves the house shakes every time it goes off! The man that's 

doing it told us that there was nothing to IY'orry about, but you 

should feel it when he blasts! You will have to do something about 

it, for we are worried about the damage it nrust be doing to the 

house!" 

The consultant explains to them that he is there to make sure 

that the house is not damaged: that is what the instrument is for. 

The blaster, who has, and uses his own instrument, did not bother 

to explain this - after all, they were too busy complaining! The 

consultant also tells them that although the vibrations will not 

harm the house, they will certainly feel the motion, and may be 

bothered by it. He tells them that they will feel the vibrations 

much more strongly if they remain inside the house, and suggests 

that they stay outdoors. 

TI1e shot is fired, and the consultant notes the 

levels: 0.15 inches per second, not nearly enough to 

damage, but certainly enough for the people to feel, 

alarm them if they are inside the house and there 

degree of structural response. 

vibration 

cause any 

and even to 

is any real 

They say to the 

it was going to 

nothing at all?" 

consultant: "That IY'as not as bad as you said 

be! But why did the blaster say we would feel 

The explanation is simply that the blaster, who is entirely 

familiar and comfortable with blasting and explosives, had told 

them merely what he believed to be true, that it was nothing to 

worry about, and that they wouldn't feel a thing. Once that was 

explained to the householders, together with the comment that the 

blaster had never been inside the house when he fired his shots, 

then a mutual understanding was established, and the foundation was 

laid for a better relationship in the future. 

The whole direction of this manual to the Mine Operator is to 

enable him to comply with the OSMRE regulations, and therefore to 

minimize the adverse effects of that operation. It is certain that 

the citizen's safety and property will be protected. It is not 

always possible to control the physical effects of blasting 

operations to such an extent that people will not be aware of the 

119 
Citizen Interests 

activity. Mining does have some adverse effects, and the annoyance that derives from those effects is genuinely regretted. One cannot build highways and bridges or new developments or, for that matter, permit and operate mines without causing annoyance to some. These 

are all legal and even desirable activities, benefiting the majority of the people, and are sometimes essential to all of us. Certainly we are all dependent on our future energy supplies, and perhaps coal is even a more acceptable source of energy to most people than nuclear sources are. Some of this coal mining activity will cause annoyance. But with care and understanding, one can at least try to remove some of the sharpest edges from that annoyance. 

ACTUAL BLAST DAMAGE CRITERIA 

The Bureau of Mines research on blast vibration damage is detailed and extensive. Among the conclusions drawn by RI 8507 (see page 29 of this manual for this document's definition of threshold damage due to blast produced ground vibration) are the following: 

• Home construction is also a factor in the minimum expected damage levels. Gypsumboard (Drywall) interior walls are more damage resistant than older, plaster on wood lath construction. 

• Practical, safe criteria for blasts that generate low-frequency ground ground vibrations are 0.75 in/sec for modern gypsumboard houses and 0.50 

in/sec for plaster on lath L,teriors. For 

frequencies above 40 Hz, a safe particle velocity maximum of 2.0 in/sec is recommended for all houses. 

• All homes eventually crack because of a variety of environmental stresses, including humidity and 

temperature changes, settlement from consolidation and variations in ground moisture, wind and even water 

absorption from tree roots. Consequently there May be 

no absolute minimum damage threshold when the vibration (from any cause, for instance slamming a door) could in 

some case precipitate a crack about to occur. 

• Human reactions to blasting can be the limiting factor. Vibration levels can be felt that are 

considerably lower than those required to produce damage. Human reaction to vibration is dependent 

on event duration as well as level. Particle velocities of 0.5 in/sec •.. ( 1-sec vibration) .•• should be tolerable to about 95 pet of the people perceiving it 

as "distinctly perceptible". 

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Citizen Interests 

This, amongst other things, at least tells us that the Bureau 

of Mines research personnel experienced considerable difficulty quantifying and qualifying blast vibration damage! lihat sort of 

difficulty will the layman have when attempting to determine if he 

has suffered blast damage? 

First, he will have to have been considerably startled or 

disturbed by the high level of the vibration, if he was there to 

observe it. If he was, a~d he actually observed damage occur, then 

he will have no doubts at all, and will be able to testify quite confidently. 

Secondly, he will have to look for small, almos.t hairline 

cracks that are fresh, without dust, spider webs, insect detritus 

or paint inside them. Small fallen flakes of paint or plaster will 

be an indication, as will be the widening of existing cracks. One 

problem in determining 1vhether an existing crack has widened, of 

course, derives from 1-1hether its original dimension was either 

known or recorded. Imagination can cause cracks to widen, especially if the observer is distressed. 

Thirdly, he may observe cracks in the jointing paper covering the separations between gypsum wall and ceiling panels. Again, he 

should make sure that these are in fact fresh, for many such small 

imperfections can pass unnoticed for years until the householder 

fears that blasting may be harming his house, and he starts looking for signs of damage. 

Many of these small cracks will typically run from the corners 

of openings such as doors or windows, or follow separations between 

building elements. Outside brickwork cracks, normally in the mortar 

between the bricks, will also follow the same pattern, running from 

the corners of openings, and also from lintel tops, or below sills. 

A "stairstep" crack is quite typical in bricl<l-rork, though a 

stairstep crack running diagonally from ground level near a corner 

to the ~-rall corner above ground level, very often indicates 

settlement rather than blast damage. 

Concrete, particularly reinforced concrete, is very resistant 

to blast vibration damage. Cracks will not normally appear in 

concrete below perhaps 10.0 inches per second, a velocity that is 

not only far higher than OSNRE regulations permit, but that would 

normally cause undisputed and quite extensive cracks to occur to 

plaster, gypsumboard and brickwork. Damage to concrete is therefore 

normally accompanied not only by exceptionally high velocities, but 

also by other, and obvious damage. 

Whenever the citizen suspects, therefore, that his home is 

suffering from the effects of excessive blast vibrations, he should 

without delay carefully and thoroughly inspect the 1vhole structure 

or engage an expert to inspect it - or, within the terms of the 

OSNRE regulations and the comments on page 10 of this manual, 

1 ~, 
Citizen Interests 

request a post-blast survey. He should document, and measure, or 

mark and date, every crack, so that widening or lengthening of 

cracks becomes a matter of documentation and not mere imagination. If he is sufficiently expert in photography, he can support any evidence he may find with good, clear, photographs, but he must 

also document the photographs carefully so that no possible confusion can arise as to identification or location. 

In fact, any concerned citizen, even ·if he is quite distant 

from the mine, and is not able to feel any vibrations, ground motion or airblast, should nevertheless inspect his home carefully from time to time. He will be able to see that his home presently has more defects than he might otherwise have imagined, and, should 

the mining operation approach closer, or use heavier explosive loading, when the vibrations will then become perceptible, he will 

be spared I:IUch worry and speculation. 

SPECIFIC COMPLAINT PROCEDURES 

STATES WITH APPROVED STATE PROGRAMS 

If residents or homeowners believe that their property has been 

damaged, or that there has been a violation of any of the blasting regulations, they may register a formal complaint with the the 

State Regulatory Authority who has jurisdiction over the program. 

A person may request an inspection of the mine where blasting is taking place. The request for an inspection should be a signed, written statement (or an oral report followed by a signed written 

statement) giving the State reason to believe that a violation 

exists. The statement should set forth a phone number and address 

where the person can be contacted. 

The identity of any person supplying information to the State 

shall remain confidential if requested by the person. If the person elects to accompany the inspector on the inspection, anonymity 

cannot be guaranteed. 

Within a specific period of time 1vhich varies from State to 

State, the person requesting the inspection must be informed of the 

results of that inspection, and a description of any enforcement 

action that was taken. 

The complainant will be info~ed of the informal and formal 

review rights that he may have under State law and regulation if he 

is not satisfied by the action of the State. It must be kept in 

mind at this point that the inspection may take the form of a 

special investigation which may include the taking of seismographic readings. This very often can take several weeks. 
Citizen Interests 

Should the complainant not receive satisfaction from the State Regulatory Authority, he may request an inspection/investigation by the Office of Surface Mining Reclamation and Enforcement (OSMRE) Field Office with 

responsibility for program evaluation in that State. 

In this case, OSMRE will revi·:w the action of the State Regulatory Authority and determine the course of action that it will take. Should a Federal inspection result, it will be carried out according to the procedures outlined in Part B of this secton, Federal Program States. 

Should OSMRE receive a complaint or request for a Federal inspection, and it is determined that the State Regulatory Authority has not been contacted, OSMRE will refer the matter to the State for resolution. 

FEDERAL PROGRAM STATES 

These are States where OSMRE has primary authority to regulate coal mining and reclamation operations under Public Law 95-87. 

A person may request a Federal inspection by furnishing any OSMRE office with a signed, written statement (or an oral report followed by a signed, written statement) giving the reason why (s)he believes that a violation exists. This statement must set forth a phone number and address where the person can be contacted. 

The identity of any person supplying information to OSMRE shall remain confidential, if requested by the person requesting the inspection. If the person elects to accompany the inspector on the inspection, anonymity cannot be guaranteed. OSMRE will keep the person's name confidential unless required to disclose the name under the Freedom of Information Act (5 U.S.C. 552) or other Federal law. 

If a Federal inspection is conducted, the complainant will be notified in advance when the inspection is to take place, and wi 11 be allowed to accompany the in spec tor during the inspection. 

Within 10 days of the Federal inspection, or, if there is 

no Federal inspection, within 15 days of receipt of the person's written complaint, the Office will send to the person the following: 

l. A description of the enforcement action, which may consist of copies of the Federal inspection report and all Notices of Violation and Cessation Orders. 

2. If no Federal inspection was conducted, an explanation of the reason why. 

123 
Citizen interests 

3. An explanation of the person's right, if any, to 

informal review of the action or inaction of the 

Agency. 

If a person is not satisfied with a decision or the results 

of an investigation into his complaints, he may ask the 

Director, OSMRE in writing for an informal review. The Agency 

has 30 days from the receipt of that request to inform the 

person of the results of that review. 

The results of the informal review will also advise a 

person of his rights to formal review under Section 525 of 

Public Law 95-87. 

The OSMRE will give copies of all materials associated with 

the results of the inspection/investigation to the person 

alleged to be in violation, except that the name of the person 

supplying information shall be removed unlss disclosue is 

required under the Freedom of Information Act, or if the person did not request confidentiality. 

REGULATORY AUTHORITIES 

OSMRE: WESTERN FIELD OFFICES 

FIELD OFFICE & ADDRESS: TELEPHONE NO: 

Office of Surface Mining (816) 374-5527 

Reclamation & Enforcement 

Kansas City Field Office 

1103 Grand Avenue, Rm. 502 

Kansas City, MO 64106 

Office of Surface Mining (505) 766-1486 

Reclamation & Enforcement 

Room 216 

219 Central Avenue, N.W. 

Albuquerque, NM 87102 

Office of Surface Mining (918) 581-7927 

Reclamation & Enforcement 

Tulsa Field Office 

333 West 4th St., Rm. 3432 

Tulsa, OK 74103 

124 

RESPONSIBLE FOR: 

Iowa, Kansas, 

Missouri & 

Nebraska 

Arizona, 

California, 

Colorado, 

New Mexico & 

Utah 

Arkansas, 

Louisiana, 

Oklahoma & 

Texas 
Citizen Interests 

Office of Surface Mining (307) 261-5776 Reclamation & Enforcement 

Casper Field Office 

100 East B St., Rm. 2128 

Casper, WY 82601-1918 

WESTERN FIELD OPERATIONS 

Administrator 

Office of Surface Mining Reclamation & Enforcement 

Brooks Towers, 2nd Floor 

1020 15th Street 

Denver, CO 80202 

(303) 844-5421 

OSMRE: EASTERN FIELD OFFICES 

FIELD OFFICE & ADDRESS: TELEPHONE NO: 

Birmingham Field Office (205) 254-0890 Office of Surface Mining 228 West Valley Ave., Rm. 302 Homewood, AL 35209 

Springfield Field Office (217) 492-4495 Office of Surface Mining 600 East Monroe St., Rm. 20 

Springfield, IL 62701 

Indianapolis Field Office (317) 269-2626 Office of Surface Mining 46 East Ohio St., Rm. 520 

Indianapolis, IN 46204 

Lexington Field Office (606) 233-7327 Office of Surface Mining 340 Legion Dr., Suite 28 

Lexington, KY 40504 

Columbus Field Office (614) 866-0578 Office of Surface Mining 2242 S. Hamilton Rd., Rm. 202 Columbus, OH 43232 

Harrisburg Field Office 

Harrisburg Transportation Center 

3rd Floor, Suite 3C 

4th & Market Sts. 

Harrisburg, PA 17101 

(717) 782-4036 

125 

Alaska, Idaho, 

Montana, North 

Dakota, Oregon, South Dakota, 

Washington & 

Wyoming 

All States 

west of the 

Mississippi 

River 

RESPONSIBLE FOR: 

Alabama, Georgia and Mississippi 

Illinois 

Indiana 

Kentucky 

Ohio & 

Michigan 

Pennsylvania, 

Rhode Island, 

Massachusetts 
Citizen Interests 

Knoxville Field Office t615) 673-4504 

Office of Surface Mining 530 Gay St., s.w., Suite 400 

Knoxville, TN 37902 

Big Stone Gap Field Office 

Office of Surface Mining P.O. Box 626 

Big Stone Gap, VA 24219 

Charleston Field Office 

Office of Surface Mining 603 Morris Street 

Charleston, WV 25301 

(703) 523-4303 

(304) 347-7158 

EASTERN FIELD OPERATIONS 

Administrator 

Office of Surface Mining 10 Parkway Center 

Pittsburg, PA 15220 

(412) 937-2828 

Tennessee 

Virginia & 

North Carolina 

West Virginia & 

Maryland 

All States 

east of the 

Mississippi 

River 

WESTERN STATE REGULATORY AGENCIES 

STATE 

AK 

AR 

co 

AGENCY: ADDRESS: TELEPHONE: 

Department of Pouch M (907) 456-2400 

Natural Resources Juneau, AK 99811 

Department of 

Pollution Control 

and Ecology 

Department of 

Natural Resources 

Division of Mined 

Land Reclamation 

8001 National Drive (501) 562-7444 

Little Rock, AR 72209 

423 Centennial Bldg. (303) 866-3567 

1313 Sherman St. 

Room 424 

Denver, CO 80203 

IA Department of Wallace State (515) 281-5851 

Soil Conservation Office Building 

KS Mined Land 

Conservation & 

Reclamation Board 

Des Moines, IA 50319 

107 West 11th St. 

p.o. Box 1418 

Pittsburg, KS 66762 

(316) 231-8540 

LA Department of Office of Conservation (504) 342-5528 

Natural Resources p.o. Box 44275 

Baton Rouge, LA 70804-4275 

126 
MO 

MT 

NM 

ND 

OK 

OR 

TX 

UT 

WY 

AL 

GA 

KY 

Citizen Interests 

Land Reel amation 

Commission 

Department of 

State Lands 

Energy & Minerals 

Department 

Pub lie Service 

Commission 

Department of 

Mines 

Dept. of Geology & Mineral Indus. 

Railroad Commission of Texas 

Dept. of Natural 

Resources, Div. of 

Oil, Gas & Mining 

Deptartment of 

Environmental 

Quality, Div. of 

Land Quality 

11 7 East Dunkin 

P.o. Box 176 

Jefferson City, MO 65102 

Capitol Station 

1625 11th Avenue 

Helena, MT 59620 

(314) 751-4041 

(406) 444-2074 

Mining & Minerals (505) 827-5974 

Division 

525 Camino de las Marquez Santa Fe, NM 87501 

Capitol Building Bismarck, ND 58505 t701) 224-2249 

4040 N. Lincoln Blvd. (405) 521-3859 

Suite 107 

Oklahoma City, OK 73105 

1129 S. Santiam Rd. 

Albany, OR 97321 

P.O. Drawer 12967 

Capitol Station 

Austin, TX 78711 

3-Triad Center #350 

355 West N. Temple Salt Lake City, 

UT 84180-1203 

Equality State 

Bank Building 3rd Floor 

122 w. 125th St. 

Cheyenne, WY 82002 

(503) 967-2039 

(512) 463-6900 

t801) 538-5340 

t)07) 777-7756 

EASTERN STATE REGULATORY AGENCIES 

Alabama Surface Box 2390 (205) 221-4130 Mining Commission Jasper, AL 35502-2390 

Surface Mined Land P.o. Box 233 (912) 744-3346 Reclamation Program Macon, GA 31202 

Natural Resources 6th Floor (502) 564-2141 

& Environmental Capitol Plaza Tower 

Protection Cabinet Frankfort, KY 40601 

127 
Citizen Interests 

and: Department of 

Sur face Mining 

Reclamation & 

Enforcement 

MD Energy 

Administrator 

and: Dept. of Natural 

Resources, Bureau 

of Mines 

MI Dept. of Natural 

Resources 

MS Dept. of Natural 

Resources 

and: Bureau of Geology 

Div. of Mining & 

Reclamtion 

OH Dept. of Natural 

Resources 

PA Department of 

Environmental 

Resources 

TN Bureau of 

Environment 

Dept. of Health 

& Environment 

VA Dept. of Mines, 

Minerals & Energy 

WV Dept. of Energy 

3rd Floor 

Capitol Plaza Tower 

Frankfort, KY 40601 

Tawes State Office 

Building 

580 Taylor Avenue 

Annapolis, MD 21401 

69 Hill Street 

Frostburg, MD 21532 

(502) 564-6940 

{301) 269-2788 

(301) 689-4136 

Stevens T. Mason Bldg. <517) 373-2329 

P.o. Box 30028 

Lansing, MI 48909 

2380 Hwy. 80 West (601) 961-5099 

Jackson, MS 39216 

2525 Northwest St. (601) 354-6228 

P.O. Box 5348 

Jackson, MS 39216 

1885 Fountain Square (614) 265-1092 

Bldg. D-3 

Columbus, OH 43224 

P.O. Box 2063 (717) 787-2267 

Harrisburg, PA 17120 

T.E.R.R.A. Bldg. 

150 9th Ave. North 

Nashville, TN 37203 

2201 W. Board St. 

Richmond, VA 23220 

(615) 741-3657 

(804) 257-0330 

1615 Washington St. E. (304) 348-3500 

Charleston. WV 25311 

1 ? R 
APPENDIX I A' 

~SION ANALYSIS 

(i) Notes on data collection. 

(ii) Notes on data recording. 

(iii) OSMRE Approved regression analysis program: LISTING. 

(iv) OSMRE Approved regression analysis program: USE. 

(v) OSMRE Approved regression analysis program: EXAMPLE. 

(vi) Notes on Vibra-Tech regression analysis program. 

(vii) Example of V-T regression analysis: 

(same data as in (v) above) 

(viii) Example of regression curves, and "blaster aid" curves 

(V-T Analysis, same data) 

(ix) V-T regression analysis calculator program. 
APPENDIX I A I : REGRESSION ANALYSIS 

( i) NOTES ON DATA COLLECTION: 

In addition to the rules outlined in Chapter 9, pages 77-78, 

the fundamental principle in good data collection is simple common 

sense. The supporting principle is consistency. lfuen it is 

remembered that these are basically exercises in comparisons, then 

these fundamentals become obvious. 

To commence any analysis exercise of this type, the area in 

which the analysis is to be performed should be documented and 

studied. All the examples in this Appendix will be based on the 

fictitious Blackrock Coal Company, of Blackrock, Wyorado, and the 

studies and analyses based on their #2 Pit Overburden will be 

typical of a small surface mine operation in the \vest, but, of 

course, will also be fictitious. 

Mrs. Smith 

0 

20501 

Mrs. Jones 

0 \0' 

l::l,800' 

Mine Buildings 

0 0920' 

0 

460 1 

6 Seismograph Location 

aoo' showing distance from shot, teet 

Figure 56. 

"Eaglefeather Mine, Blackrock, Wyorado." 

131 

17001 
Appendix 'A': Regression analysis 

Let it be assumed that the area surrounding the Blackrock tf2 Pit be as shown in Figure 56, on the previous page. The pit itself is some 1000 ft. northeast of the mine complex, and the major 

terrain features are a hill, 500ft. high, 1000· ft. northeast of 

the pit, and a river 1600 ft. southeast of it. Seismograph readings have been taken at all of the Marked seismograph locations, for both coal and overburden shots, and the results have 

not seemed to have brought any real help. The attenuation formula 

developed did not offer any real advantage over the scaled distance rule - or over the DuPont Handbook formula, and the co-efficient of detennination - the "goodness of fit" - at a disappointing .56 looked more like a "badness of fit". 

This is a situation that does not encourage much enthusiasm about the accuracy of statistical prediction techniques! 

First: COAL and OVERBURDEN results (as well as PRE-SPLIT 

results) must be separated, and analyzed separately. 

Second: Look again at Figure 56. 

There may be valid reasons why it lvas desirable to take 

measurements behind the hill 1700 ft. from the blast, and across the river 2200 ft. from it. The possibility of complaints at those sites is one very good reason to monitor. The facts that the open pit and a hill lie between one site and the blast, and the open pit and a river lie between the other site and the blast are also very good reasons why those results should be excluded from any regression analysis. 

In fact, both seismograph positions across the pit from the shot, at 820 ft. distance, are also less than desirable. In this instance, the area generally behind the blasting location should again be separated from the area in front and across the pit, unless of course consistent results indicate that the vibration attenuation characteristics are similar in the two areas. This is unlikely. 

If the western half of the area is selected for the study, it 

can then be recognized that: 

(a) the topography and geology are generally similar; 

(b) no vibration-absorbing features: pit, hill, or river, 

are present to cause untypically low results; and 

(c) the remainder of the area contains all significant 

or critical structures: the mine complex itself, and both the Smith and Jones residences, where 

complaints have originated in the past. 

Allowing that, for the sake of convenience, all overburden 

132 
Appendix 'A': Regression analysis 

blasting will take place in the marked 'shot' area, and that the explosive charge weight per delay will vary from 50-1500 lbs., if the data collected is confined to this general area, and if the rules set down in Chapter 9 are followed, then the results will be 

much more encouraging. 

A ne'" vibration prediction analysis may now be performed: 

(ii) NOTES ON DATA RECORDING: 

Again, reference should be made to Chapter 9, and also to Chapter 12. It has been already agreed that distances and explosive charge weights will be measured and not guessed. Asking some blasters for exact, measured distances and charge weights is often something of a problem, and will give an indication of how seldom these two vital measurements are known, for certain. It is essential however that the mnnber of unknmm factors be reduced as much as possible; hence, NO GUF13SING! 

lfuat is the goal of the analysis? If it is to determine the suitability of a low scaled distance, or to predict a velocity at a low scaled distance, then some of the data at least must be measured at or belmv these low scaled distances. Although the likelihood of real damage at a high scaled distance say 100 or 

more - is virtually non-existent, it is a fact that householders 

can and do complain at those high scaled distances. If damage complaints are to be countered by reference to, and prediction made 

at high scaled distances, then some of the data, at least, must be measured at or above these high scaled distances. Even if the vibration traces are flat, some recordings should be made at high scaled distances. This points again to the major disadvantage of the seismically triggered unit. It is very convenient and sometimes essential when measuring close in to the blast, at a low scaled distance, but at a high scaled distance it may not record at all! Under complaint situations, a flat trace, made at the time the shot was fired, is much better than no record at all, even when it is noted that the instrument did not trigger. 

Again, if it is desired to predict into a high particle velocity range, some at least of the data should be recorded at, or 

very near to, the highest velocity desired. Maximum charge weights per delay for reliable prediction should not greatly exceed charge weights in the gathered data, as also minimum distances predicted should not be very much less than the actual closest distances at 'vhich vibrations were measured. While it is recognized that the fundamental numerical operator in this is the non-dimensional scaled distance, and as such it should apply to any distance or charge weight, nevertheless large excursions from experimentally gathered distances or charge weights imply significantly different blasthole diameters. Significantly altered shot geometry can have 

an effect on the vibration levels (see Chapter 3, page 22, Control of Adverse Effects). To this extent, ·therefore, care and common 

133 
Appendix 'A': Regression analysis 

sense must be exercised not to extrapolate too far beyond the 

limits of the gathered data. 

In accordance with all of the foregoing principles, therefore, 

the vibration data collection exercise has been carried out, and 

the Blackrock Coal Company finds that it is in possession of 31 

good data points. 

The following computer programs will perform regression analyses on this data, first using the OS~ffiE approved program, designed specifically to satisfy the requirements of the ~fudified 

Scaled Distance Formula regulation. The same data will also be 

processed using Vibra-Tech Engineers' simpler general purpose regression program, and comparisons and comments made on the 

derived output. Both programs, incidentally, produce identical 

formulas and predictions • 

. For those without easy access to a computer, these calculations 

are still possible using a programmable hand calculator. A typical regression analysis program that will run on a Ti 59 calculator is 

also included in this Appendix. Although the input is directly in 

Scaled Dista~ce versus Velocity (Scaled Distances have to be 

calculated separately prior to running the program, as opposed to 

entering distance, charge weight and velocity), the output is 

precisely the same as the computer programs. Any differences that 

might be noted between any of these programs will be very small 

indeed, and will be due simply to variations in the accuracies of 

the operating systems. As such, they may be ignored. Any significant difference will be found to be due to an error in 

program or data entry. 

134 
Appx. 'A' OSMRE program listing 

10 REM *~'*****************~·************************************************* 20 REM 

30 REM 

40 REM 

50 REr1 

60 REM 

70 REM 

80 REM 

90 

100 

110 

120 

130 

REM 

REM 

REM 

REM 

REM 

140 REM 

150 REt-'1 

160 REM 

170 REM 

180 REM 

190 REM 

200 REM 

REM 

REM 

REM 

REM 

REM 

REM 

REM 

210 

220 

230 

240 

250 

260 

270 

PROGRAM "BLAST" 

Wr~itten By: Gt~egot'Y L. Mot'lock 

U.S. Office of Surface Minin8 

Westet·n Technical Center• 

1020 15th St. 

Den vet', CO 80202 

This pt·oc:wam pet•fot·ms a lineat" regt"ession analysis of blast 

data and will predict peak particle velocity at a given 

distance from a blast. Also, based upon your data, this program 

will pt·oduce a table showing the ma:<imum chat"ge-per·-delay f.ot' 

vcwious distances. Three items of input data at"e needed pet' 

shot; the distance ft·om the shot, the ma:dmum weight of e:<plos1VE-? 

pet' delay, and the measur ... ed ma:<imum peak pat•ticle velocity. 

This program will not extrapolate peak velocities. If you need to 

know particle velocities for a certain scaled distance, you must 

~1ave measur·ed data above and below that scaled distance. 

The pt~o~p"a.m also provides information about the 'goodness of fit' 

of the collected data. This pt•o8t"am also J=!t"ovides a 

graphical outJ=~ut to the screen. A minimum of 30 data pairs are 

needed for a reliable analysis (assuming that good data collectjor·l 

techniques have been adhered to> but, for non-critical purposes it 

is possible to derive results from a lesser number. 

280 

290 REM ********************************************************************** KEY OFF 

300 OPT! ON BASE I 

310 SCHEEN 0: WIDTH 80: COLOR 15,1,1 

320 

.330 

340 

DIM 0(99) ,WC99) .VELOC<99l ,DISCRP$(3) ,XC99>,Y<99) 

REM 

IFLG'l.=O 

350 CLS 

360 PRINT" 0 S M 

Y S I S" 

370 PRINT 

B L A S T V I B R A T I 0 N 

380 REM Choose data input method 

R E G R E S S I 0 N 

390 PRINT''Do you want to: 1. Read data from a disk file?'' 

400 PRINT" 2. Update data or edit from a disk file?" 

410 PRINT" 3. List files on disk?'' 

420 PRINT" 4. Input new data?" 

430 ON ERROR GOTO 390 

440 INPUT "[Default: 4J ";ANS1"1.. 

450 ON ERROR GOTO 0 

460 REM 

470 IF ANS1%.<0 OR ANSl%.:>4 THEN PRINT: PRINT"?--Invalid entt•y. Re-enter.": 

GOTO ~_!;90 

480 ON ANSl%. GOTO 500,550,610,690 

490 GOTO 690 

500 PRINT 

510 INPUT ''Enter file name for data file--> '',FILE$ 

520 IF FILE$="" GOTO 500 

530 GOSUB 1090 'Readit subroutine 

540 GOTO 800 

550 PRINT 

560 INPUT ''Enter file name for data file--> '',FILE$ 

570 IF FILE$="" GOTO 550 

580 GOSUB 1 090 'Read it sub t~ou tine 

135 

A hl A L 
Appx. 'A': O~flli program listing 

590 GOSUB 1540 'Manual subr~outine 

600 GOTO BOO 

610 CLS 

620 FILES 

630 INPUT "Press <ENTER> to continue 11 ,ANS$ 640 PRINT 

650 GOTO 390 

660 REM 

670 REM Default c ..... ll for· manual data input and optional save. 680 REM 

690 N:t.=O 

700 PRINT 

710 PRINT ''Enter vibration study description - 3 lines -'':PRINT'' Should include DATE, NAME 1!-. LOCATION" 

720 PRINT 

730 FOR IF.= I TO 3: LINE INPUT OISCRP$ <IF.> 

740 NEXT IF. 

750 REM 

760 GOSUB 1540 'Manual subroutine 

770 REM 

780 REM Star~t Calculations 

790 REM 

BOO SOMAX=O < 1> /SQR <ABS <W < 1> » 

BlO SDMIN=SOMAX 

820 REM 

830 DMAX=O: EMAX=O 

B40 FOR I:t.=l TO N:t. 

B50 IF D<I:t.>>DMAX THEN D~AX=O<I:t.> 

860 IF W<I:t.>>EMAX THEN EMAX=W<I:t.> 

B70 NEXT IF. 

B80 FOR I:t.=l TO N:t. 

B90 DS=D<I:t.>ISQR<ABS<W<I:t.>>> 

900 X<I:t.>=LOG<DS> 

910 Y<I:t.>=LOG<VELOC<I:t.>> 

920 REM 

930 IF DS<SDMIN THEN SDMIN=OS 

940 IF DS>SDMAX THEN SDMAX=DS 

950 NEXT IF. 

960 REM 

970 GOSUB 2450 'Regres subroutine 

9BO REM 

990 GOSUB 2900 ·outpt subr~outine 

1000 REM 

1010 SYSTEM 

1020 END 

1030 REM*********************************************************************** 1040 REM SUBROUTINE READIT 

1050 REM 

1060 REM This subroutine will read a previously created data file from disk. 1070 REM The data should consist of three 80 c:hat·ac:ter description 1 ines 

1080 REM followed by the data (distance, chat•ge, veloc:i ty). 

1090 PRINT 

1100 PRINT" -Reading file. Please wait -" 

1110 ON ERROR GOTO 1430 

1120 OPEN FILE$ FOR INPUT AS Ill 

1130 ON ERROR GOTO 1380 

1140 REM 

1150 FOR I:t.=1 TO 3 

1160 LINE INPUT tll,DISCRP$(I:t.> 

1170 NEXT I:t. 

llBO REM 

1190 N:t.=O 

136 
Appx. 1 A 1 : OSMRE program listing 

1200 REM 

1210 REM Read loop 

1220 REM 

1230 ON ERROR GOTO 1380 

1240 IF EOF(1) THEN GOTO 1310 

1250 N7.=N7.+1 

1260 INPUT#l,D<N%),W(NY.>,VELOCCN%> 

1270 GOTO 1240 

1260 REM 

1290 REM End loop 

1300 REM 

1310 ON ERROR GOTO 0 

1320 CLS 

1330 REM 

1340 GOTD 1480 

1350 REM 

136() REM Error section 

1370 REM 

1380 RESUME 1390 

1390 F'RINT 

1400 PRINT"---Ert~or while try ins to read ";FILE$;" ---" 

1410 PRINT: INPUT "Enter another~ file name fot~ data--> ",FILE$ 

1420 GOTO 1090 

1430 RESUME 1440 

1440 F'RINT 

1450 PRINT"---Errot~ while try ins to open ";FILE$;" ---" 

1460 PRINT:INPUT ''Enter another file name for data--> '',FILE$ 

1470 GDTO 1090 

1480 CLOSE 111 

1490 RETURN 

1500 REM*********************************************************************** 

1510 REM SUBROUTINE MANUAL 

1520 REM 

1530 REM This routine will allow the user to manually input data. 

1540 REM Start of data input 

1550 REM 

1560 PRINT 

1570 F'RINT "DATA INF'UT SECTION." 

1580 F'RINT 

1590 PRINT "Data must be entered in consistent units:" 

1600 PRINT ''It is usual for distance to be in 'feet·,•• 

1610 PRINT "chat~ge-pet~-delay to be in ·pound&·, and peak" 

1620 PRINT "particle velocity to be in 'inches-per~-second. ·" 

1630 F'RINT 

1640 PRINT "Press <ENTER> key alone after~ entering all data. 11 

1650 REM 

1660 REM Data input loop 

1670 REM 

1680 REMII~~~~~~#II*IIII#II#IIII#IIII#IIIIIIII##IIIIIIIIIIIIII~II#IIIIIIII~#~IIIIIIIIIIIIIIII#II#IIIIIIII###IIIIIIIIIIIIII##II 

1690 NF.=N%+1 

1700 PRINT 

1710 PRINT USING "Entet" distance No. tt4t------------------>";N%t 

1720 INF'UT "' "',D(NXI 

1730 IF D(NXI=O THEN GOTO 1860 

1740 PRINT USING "Enter maximum charge-per-delay No. tUt-->" 'N%; 

1750 INPUT " ",W<N'Y.> 

1760 IF W(NXI=O THEN GOTO 1860 

1770 PRINT USING "Enter~ particle velocity No. 11--------->"tN'Y.; 

1780 INF'UT " "',VELOC(NXI 

1790 IF VELOC(NXI=O THEN GOTO 1860 

1800 GOTO 1690 

1810 REM 

137 
Appx. 1 A 1 : OSMRE program listing 

1820 REM End of data input loop 

1830 REM 

1840 REM####################################################################### 

1850 REM 

1860 N'l.=N'l.-1 

1870 IF N/.<30 THEN PRINT;PRINT "--WARNING-- A valid analysis r·e~uir•es 30 or~ mor~e data pair~s" 

1880 REM 

1890 REM Give user a chance to edit input -data 

1900 GOSUB 3510 Edit subr~outine 

1910 REM 

1920 PRINT 

1930 INPUT ''Do you wish to save this data to disk? [Default; Yl'';ANS$ 

1940 IF ANS$= '"' THEN GOTO 1980 

1950 IF LEFT$CANS$,1)="N" OR LEFT$<ANS$,1)="n" THEN RETURN 

1960 IF LEFT$(ANS$,1><.>"Y" AND LEFT$CANS$,1><>"y" THEN F'RINT:PRINT"?---Invalid i 

nput. Re-enter.": GOTO 1920 

1970 REM 

1980 PRINT 

1990 PRINT ''You can write a new file or overwrite an old file.'' 

2000 INPUT ''Enter data lile name--> '',FILE$ 

2010 IF FILE$=~·" THEN GOTO 1980 

2020 ON ERROR GOTO 2060 

2030 OPEN FILE$ FOR OUTPUT AS #1 

2040 GOTO 2100 

2050 REM Ert~ot'· recovet~y 

2060 PRINT 

2070 PRINT "---Er~ror--could not open ";FILE$ 

2080 GOTO 1920 

2090 REM 

2100 ON ERROR GOTO 2310 

2110 REM 

REM Write data to file 

REM 

PRINT 

2120 

2130 

2140 

2150 

2160 

2170 

2180 

2190 

2200 

2210 

2220 

PRINT " - Writing file. Please Wait -'' 

FOR I'l.=! TO 3 

PRINT!!!, USING "&"; DISCRP$ <I'l.l 

NEXT IX 

REM 

FOR I'l.=1 TO N'l. 

PRINTII1,USING 

NEXT I'l. 

2230 REM 

2240 CLOSE #! 

2230 ON ERROR GOTO 0 

2260 CLS 

2270 GOTO 2330 

2280 REM 

2290 REM Ert•ot~ sect ion 

2300 REM 

2310 PRINT 

2320 PRINT "---An errot• occurred while wt•iting the data file." 

2330 STOP 

2340 REM 

2330 RETURN 

2360 REM*********************************************************************** 2370 REM SUBROUTINE REGRES 

2380 REM 

2390 REM This subroutine perfot·ms a standard 1 in eat• regression analysis. 

2400 REM It finds the line Y=BO+BlX from a scattered data set. 

2410 REM Input consists of the scattered d~ta arrays X And Y and N, the 

138 
Appx. 'A': OSMRE program listing 

2420 REM number~ of data pairs. This subr•outine outputs: BO-the Y inter·cept; 

2430 REM B1-tt1e slope; S--the sample standat•d deviation; Xba.r·-the mean of the 2440 REM x·s; SSX-the sum of the squares of X; and r-the coefficient of carr. 

24~i0 SUMX=O 

2460 SLJMY=O 

2470 SUMX2=0 

2480 SW1XY==O 

2490 SUt1Y2=0 

2500 REM 

2510 REM Calculate the sums used for calculating the sums of s9uares 

2520 REM 

2530 FOR I'l.=l TO N% 

2540 SUMX=SUMX+X(!/.) 

2550 SUMY=SUMY+Y ( !/.) 

2560 SUMX2=SUMX2+X(lf.)····2 

2570 

2580 

2590 

SUMY2=SUMY2+Y (!/.) ···2 

SUMXY•SUMXY+XCIXI*Y<IXI 

NEXT !'l. 

2600 REM 

2610 REM Calculate the sums of squares 

2620 REM 

26:!.0 XN=N% 

2640 IF N'%<3 THEN PRINT: PRINT"-----Er·t•or·--- Must have mor•e data~": STOP 

2650 REM 

2660 SSX=SUMX2-SUMX''2/XN 

26 70 SSY=SUMY2-SUMY·····2/ XN 

2680 SSXY=SUMXY-SUMX-M·SUMY I XN 

2690 REM 

2700 REM Calculate the means 

2710 REM 

2720 YBAR=SUMY/XN 

2730 XBAR=SUMX/XN 

2740 REM 

2750 REM Calculate the coefficients 

276<) REM 

2770 Bl=SSXY/SSX 

2780 BO=YBAR-·B1*·XBAR 

2790 REM 

2800 REM Calculate the sample standar~d deviation and the coefficient of cor~r~. 

2810 REM 

2820 S=SQR ( (SSY-Bl*SSXY) /XN) 

2830 R=SSXY /SQR (SSX-M·SSY) 

2840 REM 

2850 RETURN 

2860 REM****************-M·***********·*******-M-************************-M·********·M- 2870 REM SUBROUTINE OUTF'T 

2880 REt1 This subt'outine pt"ovides the output choices. 

2890 REM 

2900 CLS 

291 (l R2=R2920 Q=EXPIB0+2*S) 

2930 F'RINT"O U T P U T S E C T I 0 N" 

2940 PRINT 

2950 PRINT USII'JG "The 95/. confidence level e~uation is: PV=####.#+t:*<Ds)·""·##.:M:#";Q 

; 81 

2960 PRINT USING "The coefficient of detet"mination (t"·~-2- '9oodness of fit') is: #.##";R2 

2970 PRINT USING "This analysis has #4+# data pait'S. ";Nt. 

2980 IF N'f.<-30 THEN PRINT "--WARNING-- A valid analysis t'e~uit"es 30 or mot"e pait•s 

2991) REM 

3000 REM Find the applicable scaled distances 

139 
Appx. 1 A 1 : OSMRE program listing 

3010 REM PV for 0 to 300 ft 

3020 PV=1.25 

3030 GOSUB 4640 'Solve subt·outine 

3040 IF DS1<SDMIN THEN PRINT:PRINT"---Er~r~or~---":PRI'NT"You do not have data with 

a low enou9h scaled distance to pr~edict for a":PRINT" distance for~ 0 to 300 ft." 

:GOTO 3110 

3050 IF DSl>SDMAX THEN PRINT:PRINT"---Ert"ot .. ·---":PRINT"You do not have data with 

a high enough scaled distance to predict for a'':PRINT'' distance for 0 to 300 ft. 

":GOTO 3110 

3060 PRINT 

3070 PRINT USING "The scaled distance for 0 to 300 ft. is: ***·*:M";DSl 

3080 REM 

3090 REM PV for .301 to 5000 ft 

3100 REM 

3110 F'V=l! 

3120 GOSUB 4640 'Solve subt .. outine 

3130 IF DSl<SDMIN THEN PRINT:PRINT"---Et"t .. ot"---";PRINT"You do not have data with 

a low enough scaled distance to pr~edict fot' a":PRINT" distance for~ 300 to 5000 f 

t.":GOTD 3200 

3140 IF DS1>SDMAX THEN PRINT:PRINT"---Er~ror~---":PRINT"You do not have data with 

a high enough scaled distance to predict for~ a":PRINT'' distance fat~ 3c)Q to 5000 

ft. ": GOTO 3200 

3150 PRINT 

3160 PRINT USING "The scaled distance fat~ ::!·01 ft. to 5000 ft. is: ###.##";051 

3170 REM 

3180 REM PV fat• 5001 ft and beyond 

3190 REM 

3200 PV=.75 

3210 GOSUB 4640 'Solve subr~out ine 

3220 IF DS1<SDMIN THEN PRINT:PRINT"---Et~r~or---":PRINT"You do not have data with 

a low enough scaled distance to predict fat~ a":PRINT" distance for 5000 ft and b 

eyond .. ":GOTO 3290 

3230 IF DS1>SDMAX THEN PRINT:PRINT"---Er~r~or~---":PRINT"You do not have data with 

a high enoush scaled distance to pr~edict for a":PRINT" distance for 5000 ft and 

beyond.": GOTO 3290 

3240 PRINT 

3250 PRINT USING "The scaled distance for~ 5001 ft. and b~yond is: 4UUt.tttt'';DS1 

.3260 REM 

3270 REM Ask fat~ opt itms 

3280 REM 

3290 PRINT 

3300 PRINT"Do you want: 

3310 PRINT" 

1. Calculated charge per delay for given distance?'' 

2. Pt'inted table of distan~e vs. charge per delay and su 

mmar~y?" 

3320 PRINT" 3. Scaled Distance for~ any maximum velocity?" 

3330 PRINT" 4. Maximum velocity for any Scaled Distance!?" 

3340 PRINT" 5. Plot of data and 95/. confidence level line?" 

3350 PRINT" 6. Quit?" 

3360 INPUT "[Default: 6J";Ahl51/. 

3-370 IF ANS 1 /.=0 THEN GOTO .3450 

3380 REM 

3390 IF ANSl%<1 OR ANS1%>6 THEN PRINT:PRINT"?--Invalid input. Re-entet~. ": G 

OTO 3290 

3400 IF ANSl/.=1 

:3410 IF ANS1%=2 

3420 IF ANS1/.=3 

3430 IF ANS1%=4 

3440 IF ANSl%:::~~~5 

3450 RETURN 

THEN 

THEN 

THEN 

THEN 

THEN 

GO SUB 

GOSUB 

GO SUB 

GOSUB 

GOSUB 

4750: CLS:GOTO 3290 

5200; CLS:GDTD 3290 

6480: CLS:GOTO 3290 

6810: CLS:GOTO 3290 

7210: CLS:GDTD 3290 

3460 REM********************************************************************** 

3470 REM SUBROUTINE EDIT 

3480 REM This subt~outine will allow the editing and printout of input data 

140 
• 3490 

3500 

3510 

3520 

353C) 

3540 

Appx. 'A': OSMRE program listing 

REM Pr~intout section 

REM 

PRINT 

INPUT ''Do you want a print-out of the input data? [Default: Nl '';ANS$ 

IF ANS$="" THEN GOTO 3850 

IF LEFT$(ANS$,1)=''N'' OR LEFT$<ANS$,1)=''n'' THEN GOTO 3850 

3550 IF LEFT$ <ANS$, 1> <>"Y" AND LEFT$ <ANS$, 1 > <>"y" THEN PRINT:PRINT".·?--Inval id in 

put. 

3560 

3570 

3580 

3590 

3600 

3610 

3620 

3630 

Re-enter.": GOTO 3510 

REM 

PRINT 

PRINT" 

REM 

IF'AGE/.=0 

NCOUNT/.=0 

Please Wait, Writing to Prin~er 

REM 

IPAGE'l.=IPAGE%+1 

--" 

3640 

3650 

LPRINT CHH$(12); : LPRINT"Input data summary for:": LPRINT 

FOR I/.=1 TO 3. 

3660 

3670 

3680 

3690 

LPRINT DISCRP$CI'l.) 

NEXT I% 

LPRINT 

LPRINT USING "NOTE; Scaled Distance fat~ r•efet~ence only. 

Page,##"~IPAGE/.: LPRINT 

3700 LPRINT '' Line No. Distance/ft. Charqe/lb. Peak Velocity/ips 

Scaled Dist.*" 

3710 REM 

3720 ICOUNT'%.=0 

3730 REM 

3741) ICOUNTi' .. =ICOUNT/..+1 

3750 IF fCOUNT/.>50 T,HEN GOTO 363.0 

3~60 NCOUNT'l.=NCOUNT%+1 

3770 DST=D<NCOUNT'l.l/SQRCA8SCWCNCOUNT'l.))) 

3780 LPRINT USING " ### ####tt##### 11###!1#!1#!1!1 #####!I!I#!I#!I.U 

###:It#### .• #"; NCOUNT/.; D <NCOUNT/.) ~ W <NCOUNT%>:; VELOC <NCOUNTi:>:; OST 

3790 REM 

3800 IF NCOUNTI..<t'>li'. GOTO 3740 

3810 IFLG%=1 

3820 REM 

3830 REM Sct~een pt~intout 

3840 REM 

3850 NCOUNT'%.=0 

3861) CLS 

3870 PRINT 

3880 PRINT 

3890 PRINT 

3900 PRINT 

3910 PRINT 

3920 PRINT 

DISCRP$ (1) 

DISCRP$(2) 

DISCRPSC3) 

"* Note; Scaled Distance for t~efet~ence only." 

caled Dist. *" 

3930 PRINT 

3940 REM 

ICOUNT'l.=O 

Line No. Distance/ft. Char9e/lb. 

REM 

ICOUNT'l.=!COUNT/.+1 

IF I COUNT'l. ~.: 16 THEN GOTO 4050 

INPUT "Do you want to see mot~e data? [Default: YJ";ANS$ 

IF ANS$="" THEN GOTO 3860 

Peak Velocity/ips 

IF LEFTS<ANS$,1)="N" OR LEFTS<ANS$,1)="n" THEN GOTO 4120 

s 

3950 

3960 

3970 

;:.98() 

.399!) 

4000 

4010 

4020 

put. 

4030 

4040 

IF LEFT$CANS$,1><>''Y'' AND LEFT$CANSS,1><>''y'' THEN PRlNT:PRINT''?--Invalid in 

Re-entet~. ": GOTO 3990 

GOTO 3860 

REM 

141 
Appx. 'A': OSMRE program listing 

4050 NCOUNT'I.=NCOUNT'la+ 1 

4060 DST=D<NCOUNT~)/SQR<ABS<W<NCOUNT%))) 

4070 PRINT USIN13 " 111111 IIII(Uit+t+t+llllll llllt+t+t+llllllllll tltltllllllllllllll!ll. !Ill 

llll411141114141. 41"; NCOUNT~; D <NCOUNT1.) 1 W <NCOUNT~>; VELOC <NCOUNT~>; DST 

4080 IF NCOUNT~<N~ THEN 130TO 3970 

4090 REM 

4100 REM Editing section 

4110 REM 

4120 PRINT 

4130 PRINT"Do you wish to; 1. Edit vibration study description?" 

4140 PRINT" 2. Edit d•ta?" 

4150 PRINT'' 3. Re-print data?" 

4160 PRINT'' 4. Quit editin9?" 

4170 INPUT "CDefault: 4J ";ANS17. 

4180 IF ANS 1 %==0 THEN GOTO 4260 

4190 REM 

4200 IF ANSl'l..Cl OR ANSl%>4 THEN PRINT:PRINT"?--Invalid response. Re-enter": G 

OTO 4120 

4210 IF ANS1%=4 THEN 130TO 4260 

4220 IF ANSl%=3 THEN GOTQ 3511) 

4230 IF ANSl%•2 THEN GOSUB 4300: GOTO 4120 'Edit data 

4240 IF ANSl%=1 THEN GOSUB 4490: GOTO 4120 'Edit description 

4250 REM 

4260 RETURN 

4270 REM********************************************************************** 

4280 REM EDIT DATA 

4290 REM 

4300 PRINT 

4310 INPUT "Enter line number~ to edit, pr~ess <ENTER> to 9uit --> ",NED% 

432cj IF NEDh=O THEN GOTO 4450 

4330 IF NED'l.< 1 OR NED'l.>N'l. THEN PRINT: PRINT"?---N out of range. Re-enter~.": 

GOTO 4300 

4340 PRINT 

4350 PRINT USING "Enter~ distance No. tttl= ------------------)";NED%; 

4360 INPUT '' '',D<NED%> 

4370 IF D <NED%> ==I) THEN GOTO 4340 

4380 PRINT USING "Enter~ ma:<imum charge-per~-delay No. #tl= -->";NED%; 

4390 INPUT " ", W <NED~) 

4400 IF W<NED~>•O THEN 130TO 4380 

4410 PRINT USING "En-ter pat"ticle velocity No. tt# --------->";NED%; 

4420 INPUT '' ",VELOC(NED/.) 

4430 IF YELOC<NED~>=O THEN 13DTO 4410 

4440 130TO 4300 

44::10 RETURN 

4460 REM********************************************************************* 4470 REM EDIT DESCRIPTION 

4480 REM 

4490 PRINT 

4:500 PRINT "The current description is:": PRINT 

4510 PRINT DISCRP$ ( 1> 

45Z<) PRINT DISCRP$ <2> 

4530 PRINT DISCRP$(3) 

4540 PRINT:PRINT "Input 3 new lines of descr~iption. <Follow each line by <ENTER;: 

) " 

4550 FOR 1/.=1 TO 3 

4560 Ll NE I NF'UT D I SCRP$ < I 'l. > 

4570 NEXT I'l. 

4::180 RETURN 

4590 REM *****************************************.*************************** 4600 REM SOLVE SUBROUTINE 

4610 REM This subt"outine will find the scaled distance for a given partic:le 

4620 REM velocity. The scaled distance approximated by intersecting the 

142 
Appx. 'A' : OSMRE program listing 

4630 REM particle velocity with the pt~ediction line plus 2 standard devs. 4640 IF N%<3 THEN PRINT:PRINT "---Insufficient data for analysis: MUST have at 1 

east 3 pairs---'':STOP 

4650 IF N%>99 THEN PRINT:PRINTu---Too many data points.--- 11 :PRINT 11 Data ewrays ha 

ve been averwr it ten": STOP 

4660 REM 

4670 DS1=EXP (<LOG <PVl -B0··2*Sl /81 l 

4680 REM 

4690 RETURN 

4700 REM********************************************************************* 4710 REM SUBROUTINE INTRAT 

4720 REM This subroutine allows the user to interactively try diffet~ent 

4730 REM blasting scenarios and have the results pt"inted to the sct"een. 4740 REM 

4750 PRINT 

4760 INPUT ''Enter distance to critical structure. Press <ENTER> to 9Uit--> '',DIS TAN 

4770 IF DISTAN=O THEN GOTO 5000 

4780 IF DISTAN<O THEN PHINT:PRINT"Errot~ -- Distance must be positive~": GOTO 

4750 

4790 REM 

4800 REM Find the maximum allowable particle velocity for the given distance. 4810 REM 

4820 GOSUB 7140 'DISTAN SUBROUTINE 

4830 REM 

4840 REM Find tt1e scaled distance for the maximum particle velocity. 

4850 REM 

4860 GOSUB 4640 'Solve Subr~out ine 

4870 REM 

4880 REM Check Scaled distance ran9e 

4890 REM 

4900 IF DS1<SDMIN THEN GOSUB 5020: GOTO 4750 

4910 IF DSI>SDMAX THEN GOSU13 5090: GOTO 4750 

4920 REM 

4930 REM Output resul. ts 

4940 REM 

4950 W= <DISTAN/DS1 l '·2 

4960 PRINT 

4970 PRINT USING "At a distance of***** ft., you may use a";DISTAN 

4980 PRINT USING "maximum charge of ###### lbs./delay";W 

4990 GOTO 4750 

5000 RETURN 

5010 REM ***********ERROR OUTPUT******** 

5020 PRINT 

5030 PRINT"---Error---" 

5040 PRINT USING "The lowest scaled distance for yow~ data is tUUt.#4t";SDMIN 

5050 PRINT "You do not have data with a low enough scaled distance" 

5060 PRINT USING "to pt~edict for a distance of tt##tttt ft. ";DISTAN 

5070 RETURN 

5080 REM************ERROR OUTPUT******** 

5090 PRINT 

5100 PRINT"---Et~ror---" 

5110 PRINT USING "The highest scaled distance for your~ data is I'##.##";SDMAX 

5120 PRINT 11 You do not have data with a hish enough 5c:aled distance" 

5130 PRINT USING "to predict for a distance of tttl:##tt ft.";DISTAN 

5140 RETURN 

5150 REM******************************************************************* 5160 REM SUBROUTINE TABLE 

5170 REM This subroutine provide~ a table of maximum charee/delay for 

5180 REM different distances 

5190 REM 

5200 PRINT 

143 
Appx. 'A': OSMRE program listing 

5210 PRINT " 

5220 HEM 

Printin8 table. Please waiL. 

52-30 REM Du tpu t for 0-300 f t 

5240 REM 

5250 PV=1.25 

5260 GOSUB 4640 'SUBROUTINE SOLVE 

5270 IFLG%=1 

5280 REM 

CHR$ ( 12); 

--'' 

5290 LPRINT 

5:500 LF'R I NT 

5310 LPRINT 

5320 LF'RINT 

5-:~;:;o LF'RINT 

5340 LPRINT 

5350 LPRINT 

''OSM Charge Wei9ht per Delay Table for 0 - 300 ft'' 

USING "based on ## data pait~s for~;"; Nl.. 

DISCRP$ <I) 

OISCRF''$ <2) 

DISCRP$(3) 

5360 LPRINT 

5370 LF'RINT 

5380 LPRINT 

a.rge(lb)" 

5:390 REM 

USING "The scaled distance fat~ this distance r~ange is ###.##"~OS! 

DistCft) ChargeClb) Oist<ft) Charge<lb) 

5400 IF DSl<SDMIN THEN GOSUB 6:320~ GOlD 5570 

5410 IF OSI>SOMAX THEN GOSUB 6380: GOTO 5570 

5420 REM 

54:::::0 FOH 0:.=50 TO 1:32 STEP 2 

5440 01=1'%. 

5450 02=01+84 

5460 03=01+168 

5470 Cl=<Dl/051)"·2 

5480 C2= C02/D51) ,···2 

5490 C3=<D3/DS1> ..... 2 

OistCft) Ch 

5500 LPRINT USING " ##:lUI=# ###### ##### ##lUI 

# ######II ; 01 ; c 1 ; 02; C2; 03; C3 

5510 1\IEXT I/. 

5520 LF'RINT 

5530 IF N/.<30 THEN LPRINT"---WARNING--- A valid analysis t~equit"es :so ot' more d 

ata pairs." 

5540 REM 

5550 REM Output for 301 to 5000 ft 

5560 REM 

5570 F'V== 1 ! 

5580 GOSUB 4640 'SUBROUTINE SOLVE 

5590 REM 

5600 IF C3=0 GOTO 3290 

5610 IF 03=0 GOTO 3290 

562(' LF'R I NT CHR$ C 12) ; 

5630 LPRINT "OSM Chat"ge Wei8ht pet~ Delay Table fot' 301 - 5000 ft" 

5640 LF'RINT USING "based on## dat~ pait~s fot":";Nt. 

5650 LF'RINT DISCRPSCl) 

5660 LPRINT DISCRP$(2) 

5670 LF'RINT DISCRP$(3) 

5680 LPRINT 

5690 LPRINT USING "The scaled distance fot" this distance t'ange is ###.##";DS! 

5700 LPR!NT 

5710 LPRINT DistCft) Charge(lb) DistCft> ChargeClb> DistCft) Ch 

at~geClb>" 

5720 REM 

5730 IF DS~<SDMIN THEN GOSUB 63~0: GOTO 5960 

5740 IF DSI>SDMAX THEN GOSUB 6380: GOTD 5960 

5750 

5760 

5770 

5780 

REM 

FOR I/.=350 TO 1850 STEP 50 

01=!% 

02=01+1550 

144 
5790 03=01+3100 

5800 Cl=(Dl/081>.--2 

5810 C2= (02/DSl) --'2 

5820 C3=<D3/DS1)"2 

5830 L.PRINT USING " 

Appx. 'A': OSMRE program listing 

####4+# 

# ######'';Dl;Cl;D2;C2;D3;C3 

5840 NEXT l'l. 

5850 REI1 

5860 01=5000~ 

5870 CI=<DI/DS!)A~ 

5880 LPRINT USING " 

.. tUI .. IIII"; D I ; C I 

5890 LPRINT 

#### 

5900 LPRINT"Although the above c:hat·•ge weights-per~-delay at~e authot•ized under· the 

5910 LPRINT''regulations, they may exceed, or greatly exceed, practical limitatio 

ns." 

5920 IF N'l.<30 THEN : LPRINT"---WARNING--- A valid analysis t'E!9Uir•es 30 ot· mot·e d 

a.ta pairs." 

5930 REM 

5940 REM Output fat· 5001 ft and beyond 

5950 REM 

5960 PV=.75 

5970 GOSUB 4640 'SUBROUTINE SOLVE 

5980 REM 

5990 IF C.3=0 GOTO -3290 

6000 IF 03=0 GOTO 3290 

6010 LPRINT CHR$ < 12); 

6020 LPRINT "OSM Chat~ge Weight pet~ Delay Table for 5001 ft and beyond'' 

6030 LPRINT USING "based on ##data pa;i.t"S fat·: ";Ni'-

6040 LF'R I N"f D I SCRF'$ ( I ) 

6050 LF'RINT DISCRP$(2) 

6060 LF'RINT DISCRF'$(3) 

6070 LPR1NT 

6080 LPRINT USING "The scaled distance fot• this distance t•ange is tt#4t.##";DS1 

609(1 LPR I NT 

6100 LPRINT II 

arge < lb)" 

6110 REM 

Dist<ft) Charge(lb) Dist (ft) Char·ge(lb) 

6120 IF DS1<SDM1N THEN GOSUB 6320: GOTO 6310 

6130 IF 051)5DMAX THEN GOSUB 6380: GOTO 6310 

6140 REM 

6150 FOR 1%=5050 TO 7500 STEF' 50 

6160 01=1% 

6170 02=01+2500 

6180 03=01+5000 

6190 C1=(01/D51)A2 

6200 C2= CD2/DS1) -"2 

6210 C3=<D3/DSI)A2 

'Dist<ft) Ch 

6220 LPR1NT USING " ###tttt ###tttUt ***** ####4t4f: #### 

# ######";D1;C1;02;C2;D3\C3 

6230 NEXT 1% 

6240 LPRINT 

6250 LPR I NT "Although the above c:har~ge wei ghts-pet•-de 1 ay ar·e author~ i zed undet· the 

6260 LPRINT''resulations, they may exceed, or greatly exceed, practical limitatio 

ns." 

6270 IF NX<30 THEN : LPRINT"---W/~RNING--- A valid analysis r·equir·es 30 at· mot·e d 

ata pairs." 

6280 GOSUB 8350 'END SUBROUTINE 

6290 REM*************ERROR OUTF'UT********* 

6300 CLS 

6310 RETURN 

145 
Appx. 'A': OSMRE program listing 

6320 LPRINT 63~50 LPRINT"---Error~---" 

6:340 LPRINT USING "The minimum scaled distance fat~ this data, 4t:ttt.tt, ";SDMlN 

6:350 LPRINT"is not low enough to pr~edict for this particle velocity." 

6360 RETURN 

6370 REM***·it*********ERROR OUTPUT********* 

6380 LPRINT 

6390 LPRINT"---Ert"or--- 11 

6400 LPRINT USING "The maximum scaled distance for this data, t+tt#.##,";SDMAX 

6410 LPRINT"is not high enough to pt·edict for this particle velocity." 

6420 RETURN 

6430 REM******************************************************************* 6440 REM SUBROUTINE SCALE 

645(1 REM This subr•outine will r•epor•t the scaled distance for· any lnaximum 

6460 REM particle velocity. 

6470 REM 

6480 PRINT 

6490 INPUT "Enter~ maximum pat .. ticle velocity. Pt"ess <ENTER> to quit.---> ",PV 

6500 IF PV=O THEN GOTO 6640 

6510 REM 

6520 GOSUB 4640 'SUBROUTINE SOLVE 

6530 REM 

6540 IF PV<O THEN-PRINT:PRINT" .. ?--Invalid input. Pat"ticle velocity must be positi 

ve.": GOTO 6480 

6550 REM 

6560 IF DS1<SDMIN THEN GOSUB 6660: GOTO 6480 

6570 IF DSl>SDMAX THEN GOSUB 6720: GDTO 6480 

6580 REM 

659(1 F'R I NT 

6600 PRINT USING "Fot" a maximum pat"ticle velocity of ti=:M.:M:M ips";PV 

6610 PRINT USING "the scaled distance will be: #tUt.##";DSl 

6620 GOTD 6480 

6630 REM 

6640 RETURN 

6650 REM*************ERROR OUTPUT********* 

6660 PRINT 

6670 PRINT"---Et"t"Or'---" 

6680 PRINT USING "The minimum scaled distance for this data, tUt#.##, ";SDMlN 

6690 PRINT"is not low enough to pt"edict fot" this maximum p•t"ticle velocity." 

6700 RETURN 

6710 REM*************ERROR OUTPUT********* 

6720 PRINT 

6730 PRINT"---Et"t"or---" 

6740 PRINT USING "The ma:dmum scaled distance fot" this data, #4t4t.l:4t,"tSDMAX 

6750 PRINT" is not high enough to predict for this maximum pat"ticle velocity." 

6760 RETURN 

6770 REM********************************************************************** 

6780 REM SUBROUTINE YELO 

6790 REM This subroutine will report the max. velocity for any scaled distance 

6800 REM 

6810 PRINT 

6820 INPUT "Enter scaled distance. Press <ENTER> to quit.---> ",DSl 

6830 IF DS1=0 THEN GOTO 6950 

6840 IF 081<0 THEN PRINT:PRINT"?---Invalid input. Scaled distance must be positi 

ve.": GDTD 6810 

6850 IF DS1<SDMIN THEN GOSUB 6970: GOTO 6810 

6860 IF DSl>SDMAX THEN GOSUB 7030: GDTO q810 

6870 REM 

6880 PY=EXP <B0+2*S+Bl*LOG <DSll) 

6890 REM 

6900 PRINT 

6910 PRINT USING "Fot" a &caled di»tance of *t1=4t.4Ut, ";051 

146 
Appx. 'A': OSMRE program listing 

6920 PRINT USING ''the maximum pat·ticle velocity will be: ##.## ips'';PV 

69~JO f::.:EM 

6940 f30TO 6U 10 

69~:i0 h:ETUFi'N 

6960 I;:EM-iHHt·*lHI·-l•****"EPROH OUTPUT li"-il··lf·* li-*-IE-** 

6'·770 F'f~ 1 NT 

6980 F'F\: 11'-l'"t "---·--[: rTot··-.. ·--·-" 

-------- ------

69'?0 F'PINT USir-.IG "lhe mu1imum scaled distance fat· this data is ###.##.";SDMII-.l 

7000 F'RINT "Th~-? scaled distance input is too low." 

7010 RETURN 

7020 REt·1*****·ll--ll-1f-11·*-11--li-E.RROf:;: OUTF'UT·II-*11-*·IH*** 

70~:o PF~ I NT 

7040 F'Fi: I NT" ------Cr·r'or'------- '' 

7050 PRIN'T USING ''The maximurn scaled distance tor this data is ###.##.'';SUMAX 

7060 PRINT ''The scaled distance input is too hi8h.'' 

7U70 F\:ETURI\1 

7080 REM*~****"'******ll-******************************************************** 7090 HEM SUBROUTINE F'ARTV 

7100 nEM This :.3ubr·outine will t•etur·n the ma:dmum r·egulatot·y allowable par·ticlE.' 

7110 HEt1 veloc.ity fm' a q1· ... ·~.:m distance. rhese velocities a1·'e ft'Om 

/120 I.:;:Et1 30 CFF~ 816.6"7, 1984 

7130 HEM 

7140 F'\/:=.'75 

7150 IF DISTAN =501)1) ffiEN PV~1 ~ 

7161) 1~ DISTAN(~31)1) l'HEt~ PV=1.25 

7170 F.;£TUf\N 

7181) REM~**ll-"'~*****-~*********~*ll-********************************************** 7190 F(E!-1 SUBFI.OUT I NE G~:r4PH 

T200 RE/'1 

7'210 LOCATE 1.8,14:F'Rit,JT"I'•Iln. Ds ";~3Dl~IIN 

7'220 CLS 

7:,~30 LOCF1TE 12, ~5 

7241) Pf~IN"r•·--- F·ress :.ENlER~ when you ve finished lookin9 at qraphics ---'' 

7250 PRIN'f:PR1NT 

7260 INPUT ''Do you have a gt'aphics board, or a F'Cjr·? [Default: YJ '';ANS$ 

727u 1 r· f-W-IS$="" THEN DOTO 7320 

7281) IF LEFT$<ANSS, ll=''Y'' OR LEFT$1ANSS,ll=''y'' 1·HEN GOTO 7320 

7290 IF LEFT$((-\NS$,11 ··"N" AND LEFT$1ANS$,1l<.:="n" THEN GOTO 7250 

7300 REM Return if no 9raphics equipment 

7.:.1 0 RETURN 

T)20 ON E:Rr-t'OF: GOTO 7350 

7:~.:.0 GOTO "7410 

?:4c) REM Et'ror section 

7351:1 RESUME 7360 

7360 SCREEN 0: WIDTH 81): COLOR 15,1,1: CLS 

73'70 PRINT:PRINT''--·-Er·r·or---'' 

7381J PRINT ''Check gt•aphics capability'' 

7390 ON ERROR GOTO 0 

7400 RETURN 

741U SCREf.::N ~:CLS: lF IFLGi;=l THEN LF-'Rlt-...lf CHR$<12}; 

7420 HEM dt·aw :-~y .:,:~_:~is and scale fOt' plot 

74.Yl Lli"JE (91), 15~-5!-·(:590,156), l,BF:LINE (9(1 25}-(92,1~5), 1,BF 

7440 LINE (9U, 156) -· (9::2~ 158), 1, BF 

"/4~U LINE (256.156)- 1258.158/,1, BF 

7461) LINE 1422.156)-(4~4.158), l,BF 

7470 LINE 1588,156l-C590,158),1,BF 

7480 LINE .(90, 25>- 184, 26), 1, BF 

7490 LINE <90,67)-(84,68l,1.BF 

7500 LINE 190,11)8)-(84,109) ,l,BF 

7510 LINE (90, 155)-(84, 1561, l,BF 

7520 LOCATE 4,6:PRINT "10.0" 

7530 LOCATE 9,7:PRINT "1.0" 

147 
Appx. 'A' : OSMRE program listing 

7540 LOCATE 14,8:PRINT ".1" 

7550 LOCATE 20,8:PR1NT ".01" 

7560 LOCATE 21,12:PRINT "1" 

LOCATE 21.32:PRINT "10" 

LOCATE 21,52:PRINT "100" 

LOCATE 21,72:PRINT "1000" 

7570 

7580 

7590 

7600 

7610 

7620 

7630 

7640 

7650 

7660 

7670 

7680 

7690 

7700 

7710 

7720 

7730 

7740 

7750 

7760 

7770 

7780 

T790 

7800 

7810 

7820 

LOCATE 22,35:PRINT "Scaled Distance <Ds)" 

LOCATE 23, 19:PRINT"Plot o .. f Data and 95% Confidence Level Line" 

LOCATE 11, !:PRINT "F'ar·ticle" 

LOCATE 12, !:PRINT "Velocity" 

LOCATE 13,3:PRINT"<FV)" 

LOCATE l,l:PRINT USING "&";OISCRP$(1) 

LOCATE 2,1:PRINT USING "&:";DISCRF"$(2) 

LOCATE 3,1:PRINT USING "&";DISCRF'$(3) 

LOCATE 18,14: PRINT USING "Min. Ds = llllll.llll"; SDMIN 

LOCATE 19,14:PRINT USING "Max. Ds = IIIIII.IIII";SDMAX 

REM routine to plot scattered data set 

FOR I'l.= I TO N% 

DST=D ( !%) /SGIR <W ( !%) ) 

XX=.43*LOGCOST> 

YY=.43*LOG<VELOC<I%)) 

IF XX>3 GOTO 7820 

IF XX<O GOTO 7820 

IF YY>l GOTO 7820 

IF YY<-2 GOTO 7820 

XX=500*XX/3+90 

Y¥=155--130* CYY+2> F5 

CIRCLE <XX,YY>,2 

NEXT I% 

7830 REM plot of 95% confidence line within data limits 

7840 PVo:::CBO+Bl*LOG<SDMIN>>+2*S 

7850 PV1=CBO+Bl*LOGCSDMAX>>+2*S 

7860 YY==-. 434294*F"V. 

7870 YY=1~5-130*<YY+2)/3 

7880 Y1=.434294*F'Vl 

7890 Y1=155-130*(Y1+2)/3 

7900 XX=. 434294·111-LOG <SDMIN> 

7910 XX=90+500*XX/3 

7920 X1=.434294*LOG<SDMAX> 

79:;!.(l X1=90+500*Xl/3 

7940 LINE CXX,YY>-<·Xl,Yl) 

7950 REM Define data limits as Dashed lines 

7960 YMA=YY·-8 

7970 

7980 

7990 

8000 

8010 

8020 

8030 

8040 

8050 

8060 

8070 

8080 

8090 

8100 

8110 

8120 

8130 

8140 

8150 

FOR 1/.=1 TO 5 

LINE CXX-1,YMA>-CXX,YMA+2),1,8F 

YMA==YMA+4 

NEXT !% 

YMA=Y1-8 

FOr...: 1'1..=1 TO 5 

LINE <X1-l.YMA>-CX1~YMA+2), l,BF 

YMA=YMA+4 

NEXT 1% 

LOCATE 19,35 

PRINT 11 PV = " 

LOCATE 19,40:PRINT USING "IIIIII.IIII";GI 

LOCATE 19,46:PRINT"*Ds" 

LOCATE 18,49:PRINT USING "IIII.#II";BI 

REM Solution for scaled distance fat· 

PV=1.25 

GOSUB 4640 'SOLVE SUBROUTINE 

IF DSI<SDMIN OR DSI>SDMAX THEN DSI=O 

SF125=DS1 

148 

1.25, 1, and .7:5 IPS 
Appx. 'A': OSMRE program listing 

8160 F'V=l! 

8170 GOSUB 4640 'SOLVE SU!:JROUTINE 

8180 IF DSl<SDMIN OR DSl>SDMAX THEN DS1=0 

8190 SF!=DS! 

8200 PV=.75 

8:210 GOSUB 4640 'SOLVE SUBROUTINE 

8220 IF DS1<SDMIN OR DSl>SDMAX THEN DSI=O 

8230 SF75=051 

8240 LOCATE 4,62:PRINT" Dist. Ds" 

8250 LOCATE 5,61:F'RINT"====::::===========<=====" 8260 LOCATE 6,62:F'RINT" 0-~500 " 

8270 LOCATE 7,62:F'RINT" 301-5000" 

8280 LOCATE 8,62;PRINT"Beyond 5000" 

8290 LOCATE 6,75:PRINT USING "##.##";SF125 

8300 LOCATE 7,75:PRINT USING "##.##";SF1 

8310 LOCATE 8,75:PRINT USING "#II.##";SF75 

8320 LOCATE 24,1: INF·UT "",ANS$:SCREEN O:WIDTH 80: COLOR 15, I, 1: CLS: ON ERROR GO TO 0: RETURN 

6330 REM***********-:11·*****************************-*·**-ll·************************** 8340 REM SUBROUTINE END 

8350 LPRINT CHR$ ( 12>; 

8360 LPRINT USING "The 9'5"/. confidence level equation is: PV=####.#41=*<Ds)····tttt.tt#"; 

Q;Bl 

8370 LPRINT: LPRINT USING "lhe coef·ficient of deter~mination <r~····2- 'goodness of fit') is: #.##";R2 

8~~80 LPRINT:LPRINT:LF'RINT "Regr~ession Analysis is complete: r~efer~ to above infor~ mation, and to pr~inted" 

e.-~90 LPRINT "Distance vs. Char~ge weight tables for~ all futur~e blast de'Eii~ns." 

8400 LPRINT 

8410 LPRINT "Modified Scaled Distances st1ould be reviewed and t"enewed:" 

8420 LPRINT 1. At least once a year"." 

8430 LPRINT 2. Whenever geological or geographical site conditions change si gnificantly." 

8440 LPRINT 

ly." 

8450 RETURN 

3. Whenever blasting methods or~ blast design ct1anges significant 

149 
APPENDIX I A I : OSMRE PROGRAM USE 

The officially approved OSMRE Computer program is listed in full in IBH BASIC between pages 135 and 149. It will rnn on the IBM PC, PCjr, AT and XT and most IBM "Conpatibles". It may be entered directly from the listing, but to avoid the tedium of this very long entry, and to eliminate possible errors in entry, it is 

available on disc, in BASIC and FORTRAN, as detailed on page 166. 

The program is extremely easy to use, and has been developed specifically to enable non-computer trained personnel to perform 

the necessary calculations to permit compliance with the requirB~ents of Alternative Scaled Distance applications. It will permit the print-out of entered data as a record of blast vibrations used in the calculations, and will automatically follow the regulations in terms of permissible velocities at different distances. It will permit viewing a plot of the data and the 95% confidence level attenuation curve on the monitor screen, and it provides full data editing and storage/recall from floppy discs. It permits the printing out of a complete Charge Weight/Distance Table for each of the regulatory maximum velocity distance ranges. It also prints out the 95% upper confidence level attenuation formula, together with the coefficient of determination ("goodness of fit") to enable all non-regulatory prediction calculations to be performed. · 

Following loading the program into the computer, it will be found that the clear prompts, and built-in error protection will enable virtually anyone to follow the proper procedures. The 

program will not permit extrapolation beyond the limits of the experimental data, although the Charge Weight/Distance Tables will print out "permissible" Charge Weights possibly greatly in excess of the range of collected data. This is because the regulations 

themselves do not limit charge weights as such, only Scaled Distances, and once a particular scaled distance is permitted, then, strictly speaking, it may be expressed as any combination of distance and charge weight together. For this reason, the user is warned that he must exercise caution and discrimination, and that he should refer to the discussions on this subject on pages 133 and 134, and page 22. 

Returning to the exercise on the Blackrock Mine 112 Pit Overburden data, the following pages show a printout from the OSMRE Program, as follows: page 151: "Input data sur.Tllary", page 152: "OSH Charge Height Table for 0 - 300 ft.", page 153: "OSM Charge IJeight Table for 301 5000 ft.", page 154: "OSM Charge Height Table for 5001 ft. and beyond", and on page 155 the 95% confidence level formula, the "goodness of fit" and a warning on review and renewal. 

150 
Appx. 'A' : OSMRE program example 

Input data summary for: 

Blackrock Coal Company, Eaglefeather Mine, 

Blackrock Wyot'ado. Septembet' 3, 1986. 

+1=2 Pit Overbut'den: Alter·native Scaled Dist. 

NOTE: Scaled Distance for reference only. Page, 1 

Line No. Distance/ft. Chat·ge/ lb. Peak Velocity/ips Scaled Dist.* 

1 220 230 1.10 14.5 

2 800 925 0 .. 36 26. :::;; 

3 1200 110 0.02 114.4 

4 220 560 1.40 9.3 

5 920 690 0.34 35.0 

6 1200 420 0.28 58.6 

7 2050 245 0.02 131.0 

8 1200 85 0.02 130.2 

9 800 125 0.17 71.6 

10 2050 135 0.01 176.4 

11 BOO 1570 0.86 20.2 

12 2050 110 0.01 195.5 

13 1200 430 0.28 57.9 

14 920 247 0.18 58.5 

15 800 250 0.24 50.6 

16 460 270 0.84 28.0 

17 800 1240 0.48 22.7 

18 2050 250 0.03 129.7 

19 1200 160 0.04 94.9 

20 46(1 480 0.38 21.0 

21 225 530 1.10 9.8 

22 460 650 0.50 18.0 

23 920 330 0.21 50.6 

24 BOO 745 o. 33 29. :::; 

25 460 970 0.98 14.8 

26 460 1100 0.94 13.9 

27 2050 190 0.02 148.7 

28 800 95() 0.42 26.0 

29 920 260 o. 13 57. 1 

30 BOO 1530 0.51 20.5 

31 800 1160 0.82 23.5 

151 
Appx. 'A': OSMRE program example 

DSM Char~ge Weight per Delay Table fot• 0 - :3(10 ft 

based on 31 data pai r·s for: 

Bl ackt·•ock Coal Company, Eaglefeathet• Mine, 

Blackt•ock Wyorado. September· 3, 1986. 

#2 F'i t Ovet•bur .. den; Altet•native Scaled Dist. 

The scaled distance for· this distance r·ange is 23.56 

Dist<ftl Charse < lb > Dist(ft) Char·se < lb) Dist<ft> Char·se < lb > 

50 5 134 32 218 86 

52 5 136 33 220 87 

54 5 138 34 222 89 

56 6 140 35 224 90 

58 6 142 36 226 92 

60 6 144 :3"7 228 94 

62 7 146 38 :230 95 

64 7 148 39 232 97 

66 8 150 41 2::!.4 99 

68 8 152 42 236 100 

70 9 154 43 238 102 

72 9 156 44 240 104 

74 1 <) 158 45 242 106 

76 10 160 46 244 107 

78 11 162 47 246 109 

80 12 164 48 248 111 

S2 12 166 50 250 iD 

S4 13 168 51 252 l14 

S6 13 170 52 254 116 

SB 14 172 53 256 118 

90 15 174 55 258 120 

92 15 176 56 260 122 

94 16 178 57 262 124 

96 17 180 58 264 126 

9S 17 182 60 266 127 

100 IS 184 61 268 1.29 

102 19 186 62 270 131 

104 19 188 64 272 133 

106 20 190 65 274 135 

108 21 192 66 276 137 

110 22 194 6S 278 139 

112 23 196 69 280 141 

114 23 198 71 282 143 

116 24 200 72 284 145 

118 25 202 74 286 147 

120 26 204 .75 2SB 149 

122 27 206 76 290 152 

124 28 208 78 292 154 

126 29 210 79 294 156 

128 30 212 81 29b 15S 

130 30 214 83 298 160 

132 31 216 S4 300 lb2 

152 
Appx. 'A': OSHRE program example 

OSM Chat~ge Weight pet~ Delay rable far~ .3.01 -~ 5000 ft 

based on 31 data pairs for: 

Blackrock Coal Company, EaslefeatheJ~ Mine, 

Blackrock Wyorado. September 3, 1986. 

#2 Pit Dverbu1·den: Alternative Scaled Dist. 

The scaled distance tor this distance range is 26.99 

Dist<ft) Ct1ar•ge ( 1 b) Dist <+t> Ch.~u·ge ( lb) 

350 168 1900 4956 

400 220 1950 5220 

450 278 2000 5491 

500 343 2050 5769 

550 415 2100 6054 

600 494 2150 6:345 

650 580 2:200 6644 

700 673 2250 6949 

750 772 2:3oo 7262 

800 879 2350 7581 

850 992 2400 7907 

900 1112 2450 8240 

950 1239 2500 8580 

1000 1373 2550 8926 

1050 1513 2600 9280 

1100 1661 2650 9640 

1150 1815 27<)0 10007 

1200 1977 2750 1 o:3e1 

1250 2145 2800 10762 

1300 2320 2850 11150 

1350 2502 2900 11545 

1400 2691 2950 11946 

145() 2886 :;:;ooo 12:555 

1500 3089 3050 12770 

1550 3299 3100 1-3192 

1.600 3514 3150 1:5621 

1650 3737 3200 14057 

1700 3967 3250 14499 

1750 4204 3300 14949 

1800 4448 .3350 15406 

1850 4698 3400 15869 

Dist(ft) Char~ge ( 1 b J 

3450 16339 

.3500 16816 

3550 17300 

.3600 17791 

3650 18288 

3700 18793 

3750 19:3(1..£~ 

3800 19822 

3850 20347 

3900 20879 

3950 21418 

4000 21964 

4Q50 22516 

4100 23076 

4150 23642 

4200 24215 

4250 24"795 

4300 25:582 

4350 25976 

4400 26576 

4450 27184 

4500 27"798 

4550 28419 

4600 2904"7 

4650 29682 

4700 30324 

4750 30972 

4800 31628 

4850 32290 

4900 32959 

4950 3:3635 

5000 34.318 

Although the above charge weishts-per~-delay are authorized under the 

regulations, they may e:-;ceed, at~ gr~eatly e:<ceed, pr~actical limitations. 

153 
Appx. 'A': OSMRE program example 

OSM Charge Weight per Delay Table for~ 5001 ft and beyond 

based on 3l data pair~s for: 

Blac::krock Coal Company, Eaglefeather~ Mine, 

Blackroc:k Wyor~ado. September~ 3, 1996. 

#2 Pit Over··bur~den: Alter~na.tive Scaled Dist. 

The scaled distance for this distance range is 32.16 

Dist(ft) 

5050 

51 0(1 

5150 

5200 

5250 

5300 

5350 

5400 

5450 

550(1 

5550 

:51>00 

:51>50 

5700 

5750 

5800 

5850 

5900 

5950 

1>000 

1>050 

1>100 

6150 

6200 

6250 

6300 

1>350 

1>400 

1>4:50 

1>5<)0 

1>550 

6600 

6650 

6700 

1>750 

1>800 

1>850 

1>900 

1>950 

7000 

7050 

7100 

7150 

7200 

7250 

7300 

7350 

7400 

7450 

7500 

Char~se < lb > 

24657 

25148 

25643 

21>144 

26649 

27159 

271>74 

28193 

28718 

29247 

29781 

30320 

3081>4 

31413 

31966 

32525 

33088 

33656 

34229 

34801> 

.35389 

35976 

31>51>9 

3711>1> 

3771>7 

38374 

38981> 

391>02 

40223 

40849 

41480 

42111> 

42751> 

43402 

44052 

44707 

4531>7 

41>032 

41>701 

47375 

48055 

48739 

49428 

50121 

50820 

51523 

52231 

52945 

531>1>2 

5438[5 

Dist<ft) 

7550 

7600 

71>50 

7700 

7750 

7800 

7850 

7900 

7950 

8000 

8050 

8100 

8150 

8200 

8250 

8300 

8350 

8400 

8450 

8500 

8550 

81>00 

8650 

8700 

8750 

8800 

8850 

8900 

8950 

9000 

9()50 

9100 

9150 

9200 

9250 

9.300 

9350 

9400 

9450 

9500 

9550 

91>00 

91>50 

9700 

9750 

9800 

9850 

9900 

9950 

10000 

Char~se<lb) 

5511-3 

55845 

50582 

57324 

58071 

58823 

59580 

60341 

1>1107 

1>1878 

62654 

63435 

64220 

65011 

65800 

66606 

1>7411 

68221 

69035 

1>9855 

701>79 

71508 

72342 

73181 

74024 

74873 

75721> 

71>584 

77447 

78315 

79187 

80065 

80947 

81834 

82726 

83623 

84524 

85431 

81>342 

87258 

88179 

89105 

90035 

90971 

91911 

92856 

93801> 

9471>1 

95720 

91>1>85 

Dist (ft> 

10050 

10100 

10150 

10200 

10250 

10300 

10350 

10400 

10450 

10500 

10550 

101>00 

10650 

10700 

10750 

10800 

10850 

10900 

10950 

11000 

11050 

11100 

11150 

11200 

11250 

11300 

11350 

114<)0 

11450 

11500 

115:50 

11600 

111>50 

11700 

11750 

11800 

11850 

11900 

11950 

12000 

12050 

12100 

12150 

12200 

12250 

12300 

12350 

12400 

12450 

12500 

Char~ge ( lb) 

97654 

981>28 

991>07 

1(10591 

,101579 

1025T5 

103571 

104574 

105582 

106595 

1071>12 

108635 

1091>1>2 

110694 

111731 

112773 

113820 

114871 

115927 

116988 

118054 

119125 

120201 

121281 

122307 

123457 

124552 

125651 

121>751> 

127865 

128980 

130099 

131223 

132352 

133485 

134624 

135767 

131>915 

13801>8 

139226 

140389 

141551> 

142728 

143905 

145087 

146274 

14741>1> 

148662 

14981>4 

151070 

Although the above charge weights-per-delay are authorized under~ the 

regulations, they may exceed, or greatly exceed, practical limitations. 

154 
Appx. 1 A 1 : OSMRE program example 

The 95/. confidence level equation is: F'V= 22:.3.50*(Ds>····-1.64 

The coefficient of determination (rA2 - 'goodness of fit') is: 0.91 

Regression Analysis is complete: refer to above information, and to printed 

Distan\:e vs. Chat'se weight tables for~ -all future blast designs. 

Modified Scaled Distances should be reviewed and renewed: 

1. At least once a year. 

2. Whenever geological ot~ eeosraphic:al site conditions change significantly. 

3. Whenevet~ blasting methods or blast design changes significantly. 

155 
APPENDIX 'A': VIBRA-Trof Rl!X;RFSSION PROGRAM NOTES. 

Also available is a rather less sophisticated coEl]luter program, written in BASIC. This prograr.J can be regarded as cornpler.Jentary to the Approved OSMRE Program, since it is aimed principally at general vibration control arJd prediction rather than specific OSMRE Regulations compliance. It will permit so~What greater versatility 

in performing prediction calculations, and demands greater operator familiarity with prediction techniques. It is not essential for compliance with OSMRE regulations. For identical data input, however, it will arrive at precisely the same 95% confidence level attenuation formula and "goodness of fit", so that mathematically it is equally valid, and can be used for compliance if desired. 

The first departure from the OSMRE program occurs when the user is asked to specify square or cube root scaled distance scaling. This to enable regression analyses to be performed on air 

overpressure. While it is acknowledged that air overpressure predictions have to be made with the utmost caution because of the large number of variables involved, and therefore they should be undertaken only with great care and circumspection, nevertheless it is felt that the ability to examine possibilities in this area should not be denied the operator. If the cube root scaling option is chosen, then vibration unit references continue in terms of PSI rather than in INS/SEC. 

Data entry is somewhat different, and no prov1s1on is made for data storage to, or recall from, diskettes. Prompts are given for specific name, address, date and operation details entry, and as the program proceeds a printout is made giving a complete record of the analysis. A warning is given at the beginning that at least 30 data pairs should be used, but analysis can be run on considerably less. If analysis is made on less, the printout contains the warning that more data is needed for a valid analysis. At the conclusion of data entry, an opportunity is given for correcting any erroneous entries. Data is printed as entered, and then reprinted as corrected. 

The output then follow·s: ·the 95% confidence level arJd the 50% confidence level formulas are given, together with the coefficient of determination and the standard deviation. According to the "goodness" of the coefficient of determination, and depending on the number of data pairs input, appropriate warnings or comments 

are made. Following this, coordinateD for drawing the cUL-ves, the 50%, and both upper and lower bound 95% confidence level curves, 

are given at the maximum and at the minimum scaled distances of the input data. The reason for this is simply that, particularly when communicating with citizen groups where the tendency is to stress "worst-case scenarios", the velocities given are always maximums. Citizen groups, etc., who discuss these velocities forget this in 

many cases, and it is frequently very useful to be able to point 

156 
Appendix 'A' : V-T Program 

out that While the worst-case velocities may in fact occur 

occasionally, perhaps 5% of the time, MOST of the tine the 

velocities will best be indicated by the 50% regression line, While 

occasionally, perhaps 5% of the time, the velocities may even be as 

LOW as is indicated by the lower bound curve. 

TI1e more significant departure from the OSMRE program now 

occurs. The user is asked to enter the MAXIMilll DESIRED vibration 

level. TI1is now has no automatic reference to OSMRE regulations. It may have, if the user is applying for a modified scaled distance 

formula, or if the user wishes to control his blast vibrations in 

accordance with the Figure 1 (OSMRE Regulations) Blasting Level 01Brt. On the other hand, the operator may simply wish to conduct 

blasting operations as close as possible to one of his own rnine 

installations. If, on the advice of his consultant, it was 

considered that 4 or even 6 inches per second 1~as a safe maximum 

velocity, then this is the figure that would be input. Whatever 

level is chosen, for 1ihatever reason, regulatory or protective, the 

program then prints out a scaled distance that should result in a 

velocity not exceeding this. Based on this scaled distance, the 

program then permits calculations of maximum charge weight against 

a minimum distance, and minimum distances against a specific charge weight. 

The following pages show a printout of a regression analysis performed with the Vibra-Tech program, using the identical data 

input as the OSMRE program. In this case, however, it is presumed that the user wishes to comply with the Regulations in accordance 

with the Blasting Level 01art, and that the vibration analyses show 

that the predominant frequencies lie above 30 Hz. He will 

therefore choose 2" per second as his maximum permissible velocity, and the derived "safe" scaled distance, and the following calculations, are all based on this maximum velocity. 

The regression curve example on page 161, and the "Blaster Aid" 

curve example on page 162, are self-e:qJlanatory. They r:JaY be drawn 

from the output of either of the regression analysis programs (OSMRE providing the upper bound line only) though they are not 

essential to any prediction or compliance technique, only supportive. The "Blaster Aid" curve simply translates a scaled 

distance into a Distance vs. 01arge Weight per Delay curve, for the convenience of field personnel. 

157 
APPENDIX I A I : V-T COMPUTER PROGRAM EXAMPLE 

~!BRA-T£~ ENlliE£115 ltC. 8120 N. 51£Rlllr!N lll~D. SUIT£ ~ 

IIESTII!NSTER, CIL!IIADO 80003. T£l.EPIIJNE: 13031 42'H99o 

******************************************* .. •************* * LEAST-SQUARES REGRESSION ANALYSIS * 

********************************************************* 

Date: 

Company: 

Addr~ess: 

Operation: 

09/03/1985 

BLACKROCK COAL COMPANY 

EAGLEFEATHER MINE BLACKROCK WYDRADD 

*2 PIT OVERBURDEN 

- GROUND MOTION ANALYSIS -

31 Data pairs 

NO. DIST E/MAX PV 

1 220 230 1.1 

2 BOO 925 .3b 

3 1200 110 .02 

4 220 560 1.4 

5 920 690 .34 

6 12(")0 420 .28 

7 2(150 245 . 02 

B 1200 B5 .02 

9 BOO 125 0 17 

10 2050 135 0 01 

11 BOO 1570 .B6 

12 2050 110 0 01 

13 1200 430 .28 

14 920 247 0 lB 

15 BOO 250 .24 

11> 460 270 .B4 

17 BOO 124(1 0 4B 

lB 2050 250 .03 

19 1200 160 .04 

20 460 4BO .3B 

21 22:5 530 1. 1 

22 460 650 .5 

23 920 330 .21 

24 BOO 745 .33 

25 460 970 .9B 

26 460 1100 .94 

27 2050 190 . 02 

2B BOO 950 .42 

29 920 260 .13 

30 BOO 1530 .51 

31 BOO 1160 .82 

SQUARE ROOT SCALING 

E/MAX D!ST 1/2 PV 

LBS FT Ds IPS 

230 220 14.5 1.1 

158 
V-T computer program example 

925 800 26.3 .36 

110 1200 114.4 .02 

560 220 9.3 1.4 

690 920 35 • 34 

420 1200 58.6 .28 

245 2050 131 .02 

85 1200 1'50.2 .02 

125 800 71.6 .17 

135 2050 176.4 .01 

1570 800 20.2 .86 

110 2050 195.5 • 01 

430 1200 57.9 • 28 

247 920 58.5 • 18 

250 BOO 50.6 .24 

270 460 2B .B4 

1240 BOO 22.7 .4B 

250 2050 129.7 .03 

160 1200 94.9 .04 

480 460 21 • 3B 

530 225 9.B 1. 1 

651) 460 !B .5 

330 920 50.6 • 21 

745 BOO 29.3 • 33 

970 460 14.8 .9B 

110(1 460 13.9 • 94 

190 2050 14B.7 .02 

950 BOO 26 . 42 

260 920 57.1 • 13 

1530 800 2(). 5 .51 

1160 BOO 23.5 .B2 

The attenuation formulas at-e: 

F'V= 223.502 •<Ds)·"-1.641 (93% Confidence level) 

PV= 89.473 *<Dsl''·-1.641 (50% Confidence level) 

Coefficient of determination ('Goodness of fit'>~ .908 (1.0 =Perfect> 

This shows EXCELLENT fit of data: it may be used with confidence 

Standar-d Deviation = .458 <O=PERFECT) 

COORDINATES FOR DRAWING CURVE: 

At Ds = 9.3 Max. PV 5.75 Inches p&w Second (95;1,+) 

At Ds 9.3 Avg. PV m 2.3 Inches per Second (50;1,) 

At Ds 9.3 Min. PV = • 92 Inches per Second (95;1,-

At Ds 100 Max. PV = .117 Inches per Second ( 9:5)'.+) 

At Ds = 100 Avg. PV = • 047 Inches per Second <50%) 

At Ds 100 Min. PV .019 Inches poor Second (9:5;1,-) 

At Ds = 195.46 Ma)(. PV = .039 Inches p•r S•cond (95X+l 

At Ds 195.46 Avg. PV = .016 Inches per S•cond (50%) 

At Ds 19:5.46 Min. PV = .006 Inches per Second (95;1,-) 

159 
V-T computer program example 

MAXIMUM desired gr~ound vibr~ation is: 2 inches pet• second 

In or•der NOT TO EXCEED 2 IPS. use a scaled dista.nc:e NO LESS than: 

< 17. 69 > 

At a distance of 188 feet, NO MORE THAN: 

112 lbs pet• delay must be fir•ed 

in order that 2 ins/second NOT BE EXCEEDED! 

At a distance of 351 feet, NO MORE THAN: 

393 lbs per delay must be fired 

in ot•det• that 2 ins/second NOT BE EXCEEDED! 

If minimum charge per delay that MUST be fired is: 

112 lbs, then it must be AT LEAST 

188 feet distant from any critical structure where 

2 ins/sec MUST NOT BE EXCEEDED! 

If minimum charge per delay that MUST be fired is: 

85 lbs, then it must be AT LEAST 

1_64 feet distant fr•om any critical str·uctut•e where 

2 ins/sec MUST NOT BE EXCEEDED! 

VI BRA-!EDt EIIGUEE!IS INC. 

IESTI1INSTER, Cll.IJWIO 

9LACk:ROCK COAL COMPANY 

09/03/1985 

160 
0 

z 

0 

0 

LIJ 

(/) 

' (/)• 

LIJ 

:r 

~& 

I • 

>-

!:: 

0 

0 

..J 

LIJ 

> 

LIJ 

..J 

0 

i= • 

0:: 

<( "- . "' <(' 

LIJ 

"-

REX;RESSION CURVE EXAMPLE 

a.ACKROCK COAL COMPANY 

EAGLEFEATHER MINE 

BLACKROCK, WYORADO 

VELOCITY ATTENUATION CURVE: 31 data pairs: 

-1.641 

V - 223.502CDa) 

(UPPER BOUND, 

95'16 CONFIDENCE LEVEL) 

3 4 5 6 1 8 '1100 l 4 5 1 8 91,000 

•n Ds ~ D/W 

161 
'Blaster Aid' curve example 

EXPLOSIVE CHARGE WEIGHT PER DELAY vs. DISTANCE 

V=223.502CDar1•

641 C95%CONFIDENCE LEVEL) 

MAX. VELOCITY :2.011 /SECOND: De • 17.69 

6 7 8 t ~ 3'56789 

DISTANCE- FEET 

162 
APPENDIX I A I : V-T CALCULATOR PROGRAM 

The following calculator program may be used with the Texas Instruments Ti 59 calculator and stored on a magnetic card for ease of further loading. It will require both sides of a standard TI magnetic card. It will provide the 50% probability fornrula, the standard deviation, the coefficient of deterrrril1ation, and it will calculate PV against Scaled Distance, to a 50% confidence level. 

It will provide the "Safe" Scaled Distance, to a 95% confidence level, on the input of a maximum desired or allowed particle velocity. Based on this 95% confidence level Scaled Distance, it will calculate nuL~ charge weight per delay against distance. Following these calculations, the 95% confidence level formula may be determined, since recalling memory register 29 will display the 95% confidence level 'y' axis intercept. Used in conjunction with the forunliae provided in Appendix 'B' it will therefore permit full regression analysis, and all necessary calculations required for all OSMRE Regulations compliance and vibration predictions. 

Data entry is simply scaled distance versus particle velocity (hence the references throughout the text to "data pairs" - these 

are the data pairs used in all the calculations), so that the first 

step is to calculate all scaled distances from the data distances and charge weights. Remember that the computer programs incorporate this calculation, and do not round off the results: if it is wished to compare results from a computer program with the calculator program, scaled distances nust be used which are not rounded off. This would not be necessary in normal practice, so this fact might be recalled should the results of any calculations differ slightly. The mathematics are identical, however. 

For the first data pair, enter scaled distance, then press "A". Enter the first particle velocity, then press "B". Following each such data pair entry, the display >rill show the number of data pairs entered. Repeat this procedure for each data pair until all have been entered. Press "C" to calculate the slope, "D" to calculate the 'y' axis intercept, and "E" to calculate the standard deviation. Pressing "E"' will show the coefficient of determination, r 2 • Coordinates for the 50% curve may be obtained by entering any scaled distance and pressing "A'", when the display will then show the corresponding particle velocity. Entering any 

particle velocity that it is desired NOT to exceed, and then pressing "B' " , will then display the minimum scaled distance to 

use. Entering a distance in feet, and then pressing "C"' will calculate the maxlimEn allowable charge per delay based on this scaled distance. As already mentioned, recalling memory register 29 will permit the 95% confidence formula to be determined. 

Always use caution, for no guidance or warnings are provided! 

163 
000 

001 

002 

003 

004 

005 

006 

007 

oo::: 

00'3 

010 

011 

012 

013 

014 

015 

016 

017 

l)lg 

0 1 ·;.. 

020 

021 

022 

023 

024 

025 

026 

027 

028 

02'3 

030 

0:31 

032 

0:3::: 

0:34 

1):35 

036 

0:37 

0:3:3 

(1:3'3 

040 

041 

042 

04~: 

044 

045 

046 

047 

04:0: 

04'3 

?E. LBL 

11 A 

2:;: LN>~ 

25 CLR 

91 R/S 

76 LBL 

12 8 

c~~: LW~ 

7:3 I+ 

":-

11 R/S 

?E. LBL 

c 

43 F.:CL 

01 01 

65 ~< 

43 RCL 

04 04 

55 

43 RCL 

(1:3 

95 = 

42 ::;TO 

10 10 

43 RCL 

06 06 

75 

4:2: F.:CL 

10 10 

= 

'i-2 STD 

11 11 

43 F.:CL 

04 04 .-,.~ • .. •-:- .;:. ,::_i ... ~ ... 

c;: c:' ·-'·-· 

03 

95 

o:;: 

= 

42 :3TD 

12 12 

43 RCL 

05 05 ..,,. 

i ·-' 

42 STD 

13 

43 F.:CL 

l . ., 

·-· 

V-T calculator program 

050 

051 

052 

05::: 

054 

055 

056 

057 

05:3 

05'3 

060 

061 

062 

o.:.:;: 

064 

065 

066 

067 

(16:3 

06'3 

070 

071 

072 

07:3 

074 

075 

076 

077 

078 

07'3 

o:::o 

081 

0:32 

0~3 :;: 

(1:34 

085 

0:36 

o:::? 

o:::::: 

089 

090 

0'31 

0'32 

0'3:3 

0'34 

0'35 

0'36 

097 

09B 

0'39 

11 11 

55 

43 RCL 

1:3 13 

95 = 

42 STD 

14 14 

91 

76 LBL 

14 D 

4:3 F.:CL 

04 04 .... 

·-··-' 

4:~: RCL 

0:2: 03 

65 ::< 

43 F.:CL 

14 14 

'35 = 

42 STD 

15 15 

43 F.:CL 

01 01 

55 

43 RCL (1~: 03 

'35 = 

?5 

4:3 RCL 

15 15 

'35 = 

22 I t·lV 

2:3 Ull< 

42 STD 

16 16 

91 f.(.···::; 

76 LBL 

15 E "•3 F.:CL 

01 01 

43 F~CL 

14 14 

'35 = 

42 STD 

17 17 

43 F.:CL 

04 04 ..,, 

I ·-' 

164 

100 

1 01. 

102 

103 

104 

105 

106 

107 

108 

1 o·::< 

11 I) 

111 

112 

11 :2: 

114 

115 

116 

117 

118 

119 

120 

121 

122 

124 

125 

126 

12? 

128 

12'3 

130 

1 ~: 1 

1:32 

1 :3:;: 

134 

135 

1:36 

137 

1 ~:8 

1:39 

140 

141 

142 

143 

144 

145 

146 

147 

14:3 

149 

17 17 

'35 = 

42 STD 

18 18 

43 RCL 

16 16 

23 LN>:: 

65 >~ 

43 F.:CL 

18 18 

g.:. - .J ..,~ 

( ·-· 

= 

4:3 RCL 

06 06 

'35' = 

42 ::;ro 

19 19 

4:3 F~CL 

14 14 

65 ::< 

02 2 

t.5 ::< 

43 F~CL 

1 '3 1 9 

•=t 1:' - ·-· 

= 

42 STD 

20 20 

43 RCL 

16 16 

2:3 LN::~: 

._ 

":•-? .. _, , '··' ...... ':-

42 STD 

21 21 

4:3 F.:CL o~: 03 

:35 1 ..... ::-:; 

42 STD 

:22 .-. .-, .::..::. 

4:3 RCL 

14 14 ·~· ·:· '···-=· ·-· ·-· {' .... 65 ::< 

4:3 RCL 

05 05 

85 + 

4:3 RCL 

02 02 

85 + 

4:3 RCL 

20 20 
150 

151 

152 

15:;: 

154 

155 

156 

157 

15S 

15'3 

160 

161 

162 

1 •. -, .. t•-.) 

164 

1 .• c:' 

.i. t·--· 

166 

'35 = 

65 ::< 

43 RCL 

.-.. -, .-, .-, .:::..::. .::..::. 

9~5 = 

85 + 

43 RCL 

21 21 

95 = 

:::4 n,: 

42 STD ":':• ·:· ·:• ':• .:..·-· .:.-·-· ·:! 1 ~: .. ···::; 

{ t· L.E:L. 

10 E' 

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1 1 11 

167 :::3 ;:-:;::: 

16'3 

170 

1 71 

172 

173 

174 

42 ::;nJ 

Z:4 24 

43 RCL 

01 01 

~~ 

·-··-· 43 F.:CL 

175 03 03 

176 '35 = 

1 7'3 

1 :::o 

181 

.:t2 STO .-, c:' .-, C' 

.::,._1 .::.-• 

43 F~CL 

02 02 

1:::2 43 F.:CL 

185 

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1B7 

1 :::::: 

1S9 

1'30 

191 

1 '3 c: 

1'33 

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.;:.._1 .::. ·-· 

95 = 

26 26 

43 F.:CL 

24 24 ~~ 

._l._l 

194 43 F:~CL 

195 ~~t. 26 

1 '3t. 

1'37 

= ·~ 1 F:.·· ::; 

i '=' LE:L 

lt. A• 

V-T calculator program 

200 

201 

202 

203 

204 

205 

206 

207 

20'3 

210· 

211 

212 

213 

214 

~~ 15 

216 

42 STD 

27 27 

43 RCL 

16 16 

65 X 

53 ( 

43 RCL. 

•:>7 ·:<7 

~· .:-1 

45 '·j'X 

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14 14 

54 ) 

'315 = 

'31 R ..... s 

76 LE:L 

17 E:· 

42 STD 

217 28 2:3 

21::: 

219 

220 

221 

222 

.-, .-,.-, 

.::..::.-:· 

224 

53 ( 

5:3 ( 

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65 

02 

54 

2 

) 

225 22 r t-~··.·' 

226 23 Ut·; 

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2:32 2'3 2'3 ·:··:··:· 

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234 4::: F.:CL .-.--.1::" 

.;.: . .:·--· ~~36 

237 

··:.·:··=· 

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240 

241 

242 

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2'3 2'3 

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245 42 ::;To ~:46 

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24'? 

30 ::::o 

'31 F.: .. ···::; 

, t• LBL 

:::: c:· 

165 

250 

251 

252 

253 

254 

255 

256 

257 

258 

259 

260 

261 

42 STD 

31 31 

53 ( 

43 RCL 

31 31 

55 

43 RCL 

:;:o 30 

54 ) 

'35 = 

-:'11 R ..... s 
COMPUTER AND CALCULATOR PROGRAM AVAilABILITY 

The three computer/calculator programs described in Appendix 

'A' of this manual are: 

1. The OSMRE Approved Regression Analysis Computer Program. 

This program, written by OSMRE engineers, is designed specifically 

to permit compliance with the Modified Scaled Distance Option, 

[(Section 816.67(d)(3)(ii)]. It will also permit compliance with 

other options, since it provides the 95% upper confidence level 

vibration attenuation formula from which all other prediction 

calculations may be made. It will permit data storage onto disc, 

and data retrieval from disc. It will run on IBM PC and 

compatibles. The program is written in BASIC and FORTRAN on a 5\" 

Floppy Diskette, and includes full instructions for use. 

2. The V-T "General Use" Regression Analysis Computer Program. 

This program is not specific to any particular OSMRE Regulations 

compliance option, but pernrits more versatile prediction and 

control. It will also permit full OSMRE compliance. It does not 

provide for data storage or retrieval on disc. It will run on IBM 

PC and compatibles. The program is written in BASIC only on a 5\" 

Floppy Diskette, and includes full instructions for use. 

3. The V-T Regression Analysis Program for the Ti59 Calculator. 

TI1is is a simplified calculator program that will permit both OSMRE 

Regulations compliance and prediction and control, since it will 

provide the 95% confidence level attenuation fo~a. The program 

is stored on a Ti Magnetic Card, and includes full instructions for 

use. 

Any of the above may be obtained by calling the following 

toll-free number: 

1-800-233-6181 

166 
APPENDIX 'B' 

USEFUL FORMULAE 
USEFUL FORI'1ULAE 

1. SCALED DISTANCE RELATIONSHIPS: 

t 

Os = 0/W W = (0/0s) 2 0 = Os x W 

Where D = distance, feet; and W = charge weight 

per delay, 1 bs. 

t 

2. VELOCITY ATTENUATION CURVE RELATIONSHIPS: 

-B 

PV = H x ( Ds) 1/s 

Ds = (H/V) 

Where H = y axis intercept @ Ds = 1 and B = slope. 

3. AIR OVERPRESSURE 

4. 

dB = 20 log (P/Po) 

where P = OVERPRESSURE, P.S.I. 

-9 

and Po= 2.9 x 10 (base reference pressure). 

GENERAL: SEISMIC MOTION: 

PV = 2nfA 

PV 

A = 2nf 

PV 

f = lii7i 

where f = frequency, Hz 

A = single displacement, 

t 

VR = (L 2 + V2 + T2 ) 

NOTE: TRUE Resultant: Waveform must be searched to 

find Max VR, where L, V, & T all occur at the 

same instant, otherwise VR is PSEUDO Resultant. 

ER = 0.274 VR 2 ("Energy Ratio") 

5. ACCELERATION: 

2TTfV 4n 2 f2A 

g = 386 ; g = 386 

169 

386g 

PV = 2nf 

ins. 
APPENDIX I c I 

GLOSSARY 
GLOSSARY 

From Bureau of Mines Information Circular IC 8925, 1983. 

ACOUSTICAL IMPEDANCE. -The nathematical expression characterizing a material as to its energy transfer properties. The product of its unit density and its sonic velocity. 

ADOBE CHARGES. -See mud cap. 

AIRBLAST. -An airborne shock wave resulting from the detonation of explosives. May be caused by burden movement or the release of expanding gas into the air. Airblast may or may not be audible. 

AIRDOX. -A system that uses 10,000 psi cor.1pressed air to break undercut coal. Airdox will not ignite a gassy or dusty atmosphere. 

AUJMINUM. -A metal conmonly used as a fuel or sensitizing agent in explosives and blasting agents. Normally used in finely divided particle or flake form. 

AMERICAN TABLE OF DISTANCES. -A quantity/distance table published by IME as Pamphlet No. 2, which specifies safe explosive storage distances from inhabited buildings, public highways, passenger railways and other stored explosives materials. 

AMMJNIUM NITRATE (AN). -The most conmonly used oxidizer in 

explosives and blasting agents. Its formula is NH~N0 • 

ANFO. -An explosive material consisting of ammonium nitrate and fuel oil. The most commonly used blasting agent. 

AXIAL PRIMING. -A system for priming blasting agents in which a core of priming material extends through most or all of the blasting agent charge length. 

BACK BREAK. -Rock broken beyond the limits of the last row of holes. 

BACK HOLES. -The top holes in a turmel or drift round. 

BASE CHARGE. -The main explosive charge in a detonator. 

BATF. -Bureau of Alcohol, Tobacco and Firearms, U.S. Department of the Treasury, ~~ch enforces explosives control and security regulations. 

173 
Glossary 

BEDS OR BEDDING. -Layers of sedinentary 

by a surface of discontinuity. As a rule, 

separated along these planes. 

rock, usually separated 

the rock can be readily 

BENCH. -The horizontal ledge in a quarry face along which holes 

are drHled vertically. Benching is the process of excavating 

whereby terraces or ledges are worked in a stepped sequence. 

BINARY EXPLOSIVE. 

ingredients, such as 

shipped and stored 

high explosive. 

-An explosive based on two nonexplosive 

nitromethane and ammonium nitrate, which are 

separately and mixed at the jobsite to form a 

BLACK POWDER. -A low explosive 

nitrate, carbon, and sulfur. 

because of its low energy, 

sensitivity to sparks. 

consisting of sodium or potassium 

Black powder is seldom used today 

poor fume quality, and extreme 

BLAST. -The detonation of explosives to break rock. 

BLAST AREA. -The area near a blast within the influence of flying 

rock missiles, or concussion. 

BLASTER. -A qualified person in charge of a blast. Also, a person 

·(blaster-in-charge) who has passed a test, approved by OSM, which 

certifies his or her qualifications to supervise blasting 

activities. 

BLASTERS' GALVANOMETER; BLASTERS' MULTIMETER. -See galvanometer; 

nrultimeter. 

BLASTHOLE. -A hole drilled in rock or other material for the 

placement of explosives. 

BLASTING AGENT. -An explosive that meets prescribed criteria for 

insensitivity to initiation. For storage, any material or mixture 

consisting of a fuel and oxidizer, intended for blasting, not 

otherwise defined as an explosive, provided that the finished 

product, as r:lixed and packaged for use or shipment, cannot be 

detonated by means of a No. 8 test blasting cap when unconfined 

(BATF). For transportation, a material designed for blasting which 

has been tested in accordance with CFR49, Section 173.14a, and 

found to be so insensitive that there is very little probability of 

accidental initiation to explosion or transition from deflagration 

to detonation (DOT). 

BLASTING CAP. -A detonator that is initiated by safety fuse 

(MSHA). See also detonator. 

BLASTING CIRCUIT. -The electrical circuit used to fire one or 

more electric blasting caps. 

174 
Glossary 

BLASTING CREW. -A group of persons whose purpose is to load 

explosive charges. 

BLASTING MACHINE. -Any machine built expressly for the purpose of 

energizing electric blasting caps or other types of initiator. 

BLASTING MAT. -See mat. 

BLASTING SWITCH. -A switch used to connect a power source to a blasting circuit. 

BLISTERING. -See mud cap. 

BLOCKHOLE. -A hole drilled into a boulder to allow the placement of a small charge to break the boulder. 

BOOSTER. -A unit of explosive or blasting agent used for 

perpetuating or intensifying an explosive reaction. A booster does 

not contain an initiating device but is often cap sensitive. 

BOOTLEG. -That portion of a borehole that remains relatively intact after having been charged with explosive and fired. A bootleg may contain unfired explosive and should be considered hazardous. 

BOREHOLE (Blasthole). -A drilled hole, usually in rock, into which explosives are loaded for blasting. 

BOREHOLE PRFSSURE. -The pressure which the hot 

detonation exert on the borehole wall. Borehole 

primarily a function of the density of the explosive of explosion. 

gases of 

pressure is 

and the heat 

BRIDGE WIRE. -A very fine filament wire imbedded in the ignition element of an electric blasting cap. An electric current passing through the lYire causes a sudden heat rise, causing the ignition element to be ignited. 

BRISANCE. -A property of an explosive roughly equivalent to 

detonation velocity. An explosive with a high detonation velocity has high brisance. 

BUBBLE ENERGY. -The expanding gas energy of an explosive, as 

measured in an underwater test. 

BULK MIX. -A nass of explosive material prepared for use without packaging. 

BULK STRENGTII. -A strength of an explosive per unit volume. 

BULLDOZE. -See mud cap. 

175 
Glossary 

BURDEN. -The distance from an explosive charge to the nearest 

free or open face. Technically, there may be an apparent burden and 

a true burden, the latter being measured in the direction in which 

displacement of broken rock will occur following firing of the 

explosive charge. Also, the amount of material to be blasted by a 

given hole, given in tons or cubic yards. 

BURN CUT. -A parallel hole cut employing several closely spaced blastholes. Not all of the holes are loaded with explosive. The cut 

creates a cyHndrical opening by shattering the rock. 

BUS \~IRES. -The two wires, joined to the connecting wire, to 

which the leg wires of th~ electric caps are connected in a 

parallel circuit. Each leg wire of each cap is connected to a 

different bus wire. In a series-in-parallel circuit, each end of 

each series is connected to a different bus wire. 

BUTT. -See bootleg. 

CAP. -See detonator. 

CAPPED FUSE. -A length of safety fuse to which a blasting cap has 

been attached. 

CAPPED PRIMER. -A package or cartridge of cap-sensitive explosive which is specifically designed to transmit detonation to other 

explosives and which contains a detonator (MSHA). 

CAP SENSITIVITY. -The sensitivity of an explosive to initiation, expressed in terms of an IME No. 8 test detonator or a fraction 

thereof. 

CARBON MONOXIDE. - A poisonous gas created by detonating explosive materials. Excessive carbon monoxide is caused by an 

inadequate amount of oxygen in the explosive mixture (excessive fuel). 

CARDOX. -A system that uses a cartridge filled with liquid carbon 

dioxide, which, when initiated by a mixture of potassium perchlorate and charcoal, creates a pressure adequate to break 

1mdercut coal. 

CARTRIDGE. -A rigid or semirigid container of explosive or 

blasting agent of a specified length or diameter. 

CARTRIDGE COUNT. -The number of 1~- by 8-in. cartridges of 

explosives per 50-lb case. 

176 
Glossary 

CARTRIDGE STRENGTH. -A rating that compares a given volume of 

explosive with an equivalent volume of straight nitroglycerin 

dynamite, expressed as a percentage. 

CAST PRIMER. -A cast unit of explosive, usually pentolite or 

composition B, commonly used to initiate detonation in a blasting 

agent. 

CHAMBER.IN:;. -The process of enlarging a portion of blasthole 

(usually the botto~) by firing a series of small explosive charges. 

Chambering can also be done by mechanical or thermal methods. 

CHAPMAN-JOUQUET (C-J) PLANE. -In a detonating explosive column, 

the plane that defines the rear boundary of the primary reaction 

zone. 

CIRCUIT TESTER. -See galvanometer; multimeter. 

CLASS A EXPLOSIVE. -Defined by the U.S. Department of 

Transportation (DOT) as an explosive that possesses detonating or 

otherwise maxi.nun hazard; such as, but not limited to, dynamite, 

nitroglycerin, lead azide, black powder, blasting caps, and 

detonating primers. 

CLASS B EXPLOSIVE. -Defined by DOT as an explosive that possesses 

flammable hazard; such as, but not limited to, propellant 

explosives, photographic flash powders, and some special fireworks. 

CLASS C EXPLOSIVE. -Defined by DOT as an explosive that contains 

Class A or Class B explosives, or both as components but in 

restricted quantities. For example, blasting caps or electric 

blasting caps in lots of less than 1,000. 

COLLAR. -The mouth or opening of a borehole or shaft. To collar 

in drilling means the act of starting a borehole. 

COLLAR DISTANCE. -The distance from the top of the powd.er column 

to the collar of the blasthole, usually filled with stemming. 

COillMN CHARGE. -A long, continuous charge of explosive or 

blasting agent in a borehole. 

COMMERCIAL EXPLOSIVES. -Explosives designed and used for 

commercial or industrial, rather than military applications. 

COMPOSITION B. -A mixture of RDX and TNI which, when cast, has a 

density of 1.65 g/cu em and a velocity of 25,000 fps. It is useful 

as a primer for blasting agents. 

177 
Glossary 

CONDENSER-DISCHARGE BLASTING ~lACHINE. · -A blasting ~chine that 

uses batteries or magnets to energize one or more condensers (capacitors) whose stored energy is released into a blasting circuit. 

CONFINED DETONATION VELOCITY. -The detonation 

explosive or blasting agent under confinement, borehole. 

velocity of an 

such as in a 

CONNECTING WIRE. -A wire, smaller in gage than the lead wire, used in a blasting circuit to connect the cap circuit ~v.ith the lead wire or to extend leg wires from one borehole to another. Usually considered expendable. 

CONNECTOR. -See MS connector. 

CONTROlLED BLASTING. -Techniques used to control overbreak and produce a competent final excavation wall. See line drilling, presplitting, smooth blasting, and cushion blasting. 

CORDEAU DETONANT FUSE. -A term used to define detonating cord. 

CORNISH CUT. -See parallel hole cut. 

CORO~ CUT. -See parallel hole cut. 

COUPLING. -The degree to which an explosive fills the borehole. Bulk loaded explosives are completely coupled. Untamped cartridges are decoupled. Also, capacitive and inductive coupling from powerlines, which may be introduced into an electric blasting circuit. 

COYOTE BLASTING. -The practice of driving tunnels horizontally into a rock face at the foot of the shot. Explosives are loaded into these tunnels. Coyote blasting is used where it is impractical to drill vertically. 

CRITICAL DIAMETER. -For any explosive, the minirrRm1 diameter for propagation of a stable detonation. Critical diameter is affected 

by confinement, temperature, and pressure on the explosive. 

CROSSLINKING AGENT. -The final ingredient added to a water gel or slurry, causing it to change from a liquid to a gel. 

CURRENT LIMITING DEVICE. -A device used to prevent arcing in electric blasting caps by limiting the amount or duration of 

current flow. Also used L, a blaster's galvanometer or multimeter 

to assure a safe current output. 

CUSHION BLASTING. -A surface blasting technique used to produce competent slopes. The cushion holes, fired after the main charge, have a reduced spacing and employ decoupled charges. 

178 
Glossary 

ClJSHION STICK. -A cartridge of explosive loaded into a 

Bmll-diameter: borehole before the primer. The use of a cushion 

:.>tick is not generally reconrnended because of possible resulting 

bootler;s. 

CUT. -An arrangefilent of holes used in underground mining and 

tunnel blasting to provide a free face to which the remainder of 

the round can break. Also the opening created by the cut holes. 

ClJTOFFS. -A portion of a column of explosives that has failed to 

detonate owing to bridging or a shifting of the rock formation, often due to an improper delay system. Also a cessation of 

detonation in detonating cord. 

DEAD PRESSING. -Desensitization 

pressurization. Tiny air bubbles, literally squeezed from the mixture. 

of an explosive, caused by required for sensitivity, are 

DECIBEL. -The unit of sound pressure conrnonly used to measure 

airblast from explosives. The decibel scale is logarithmic. 

DECK. -A small charge or portion of a blasthole loaded with 

explosives which is separated from other charges by stenrning or an 

air cushion. 

DECOUPLING. -The use of cartridged products significantly smaller 

in diameter than the borehole. Decoupled charges are normally not 

used except in cushion blasting, smooth blasting, presplitting, and 

other situations where crushing is undesirable. 

DEFLAGRATION. -A subsonic but extremely rapid explosive reaction 

accompanied by gas formation and borehole pressure, but without 

shock. 

DELAY BLASTING. -The use of delay detonators or connectors that 

cause separate charges to detonate at different times, rather than 

simultaneously. 

DELAY CONNECTOR. -A nonelectric, short-interval delay device for 

use in delaying blasts that are initiated by detonating cord. 

DELAY DETONATOR. -A detonator, either electric or nonelectric, with a built-in element that creates a delay between the input of 

energy and the explosion of the detonator. 

DELAY ELECTRIC BLASTING CAP. -An electric blasting cap with a 

built-in delay that delays cap detonation in predetermined time 

intervals, from milliseconds up to a second or more, between successive delays. 

179 
Glossary 

DELAY ELEMENT. -That portion of a blasting cap which causes a 

delay between the instant of application of energy to the cap and 

the time of detonation of the base charge of the cap. 

DENSITY. -The weight per unit volume of explosive, expressed as 

cartridge count or grams per cubic centimeter. See loading density. 

DEPARTMENT OF TRANSPORTATION (DOT). 

regulates safety in interstate shipping hazardous materials. 

DETALINE SYSTEM. -A nonelectric system 

caps in which the energy is transmitted 

means of a low-energy detonating cord. 

-A Federal agency that 

of explosives and other 

for initiating blasting through the circuit by 

DETONATING CORD. -A plastic-covered core of high-velocity elqplosives, usually PETN, used to detonate charges of explosives. The plastic covering, in turn, is covered with various combinations 

of textiles and waterproofing. 

DETONATION. -A supersonic explosive reaction that propagates a 

shock wave through the explosive accompanied by a chemical reaction 

that furnishes energy to sustain the shock wave propagation in a 

stable manner. Detonation creates both a detonation pressure and a 

borehole pressure. 

DETONATION PRESSURE. -The head-on pressure created by the 

detonation proceeding down the explosive column. Detonation 

pressure is a function of the eA~losive's density and the square of 

its velocity. 

DETONATION VELOCITt. -See velocity. 

DETONATORS. -Any device containing a detonating charge that is 

used to initiate an explosive. Inclurles, but is not limited to, blasting caps, electric blasting caps, and nonelectric 

instantaneous or delay blasting caps. 

DITCH BLASTING. -See pro~agation blasting. 

DOT. -See Department of Transportation. 

DOWNLINE. -The line of detonating cord in the borehole which 

transmits energy from the trunkline down the hole to the primer. 

DRILLING PATTERN. -See pattern. 

DROP BALL. -Known also as a headache ball. An iron . or steel 

weight held on a wire rope which is dropped from a height onto 

large boulders for the purpose of breaking them into smaller 

fragments. 

180 
Glossary 

DYNAMITE. -The high explosive L,vented by Alfred Nobel. 

explosive in which .the sensitizer is nitroglycerin or 

explosive oil. 

Any high 

a similar 

FlJIELON PATTEPJN. -A delay pattern that causes the true burden, at 

the time of detonation, to be at an oblique angle from the original free face. 

ELECTRIC BLASTING CAP. -A blasting cap designed to be initiated 

by an electric current. 

ELECTRIC STOR!1. -An atmospheric disturbance of intense electrical 

activity presenting a l1azard in all blasting activities. 

EMULSION. -An explosive material containing substantial 

of oxidizers dissolved in water droplets surrounded 

immiscible fuel. Similar to a slurry in some respects. 

amounts 

by an 

EXPLODING BRIDGE HIRE (EBW'). -A wire that explodes upon application of current. It takes the place of the primary explosive in an electric detonator. An exploding bridge wire detonator is an 

electric detonator that employs an exploding bridge wire rather 

than a primary explosive. An exploding bridge wire detonator 

functions instantaneously. 

EXPLOSION. -A thermochemical process in which mixtures of gases, solids or liquids react with the almost instantru1eous formation of 

gaseous pressures and sudden heat release. 

EXPLOSION PRESSURE. -See borehole pressure. 

EXPLOSIVE. -Any chemical mixture that reacts at high velocity to 

liberate gas and heat, causing very high pressures. BATF 

classifications include high e:l.."Plosives and low explosives. Also, 

any substance classified as an explosive by DOT. 

EXPLOSIVE MATERIALS. -A term which includes, but is not 

necessarily limited to, dynamite and other high explosives, slurries, water gels, emulsions, blasting agents, black powder, pellet powder, initiating explosives, detonators, safety fuses, squibs, detonating cord, igniter cord, and igniters. 

EXTRA DYNAMITE. -Also called ammonia dynamite, a dynamite that 

derives the major portion of its energy from am8onium nitrate. 

EXTRANEOUS ELECTRICITY. -Electrical energy, other than actual 

firing current, which may be a hazard with electric blasting caps. Includes stray current, static electricity, lightning, radio-frequency energy, and capacitive or inductive coupling. 

181 
Glossary 

FACE. -A rock surface exposed to air. Also called a free face, " 

face provides the rock with room to expand from fragmentation. 

FIRING CURRENT. -Electric current purposely int~oduced into a 

blasting circuit for the purpose of initiation. Also, the amount of 

current required to acUvate an electric blasting cap. 

FIRING LINE. -A line, often permanent, extending from the firing 

location to the electric blasting cap circuit. Also called lead 

wire. 

FLASH OVER. -Sympathetic detonation bet~;een explosive charges or 

between charged blastholes. 

FLYROCK. -Rock that is propelled through the air fror:1 a blast. 

Excessive flyrock may be caused by poor blast design or unexpected 

zones of weakness in the rock. 

FRACTURING. -The breaking of rock with or without t:lOVet:lent of the 

broken pieces. 

FRAGMENTATION. -The extent to which a rock is broken into pieces by blasting. Also the act of breaking rock. 

FUEL. -An ingredient in an explosive ~mich reacts 1-1ith an 

oxidizer to forrn gaseous products of detonation. 

FUEL OIL. -The fuel, usually No. 2 diesel fuel, in AN-FO. 

FUME CLASSIFICATION. -An IME quantification of the amotmt of 

fumes generated by an explosive of blasting agent. 

FUME QUALITY. -A measure of the toxic funes to be expected ~en a 

specific explosive is properly detonated. See fumes. 

FUMES. -Noxious or poisonous gases liberated fror:1 a blast. May be due to a low fume quality explosive or inefficient detonation. 

FUSE. -See safety fuse. 

FUSE LIGHTER. -A pyrotechnic device for rapid and dependable lighting of safety fuse. 

GALVANOMETER. -(More properly called blasters' galvanometer.) A 

measuring instrument containing a silver chloride cell and/or a 

current limiting device which is used to measure resistance in an 

electric blasting circuit. Only a device specifically identified as 

a blasting galvanometer or blasting multit:leter should be used for 

this purpose. 

182 
Glossary 

GAP SENSITIVIlY. -A measure of the distance across which an 

explosive can propagate a detonation. The gap may be air or a 

defined solid material. Gap sensitivity is a measure of the 

likelihood of sympathetic propagation. 

GAS DETONATION SYSTEM. -A system for initiating caps in which the 

energy is transmitted through the circuit by oeans of gas 

detonation inside a hollow plastic tube. 

GELATIN. -An explosive or blasting agent 

consistency. The term is usually applied to 

may also be a water gel. 

that has a gelatinous 

a gelatin dynamite but 

GELATIN DYNAMITE. -A highly lmter-resistant dynamite with a 

gelatinous consistency. 

GENERATOR BLASTING MACHINE. -A blasting machine operated by 

vigorously pushing down a rack bar or twisting a handle. Now 

largely replaced by condenser discharge blasting machines. 

GRAINS. -A system of weight measurement in 1vhich 7,000 grains 

equal 1 lb. 

GROUND VIBRATION. -A shaking of the ground caused by the elastic 

wave emanating from a blast. F.xcessive vibrations may cause damage 

to structures. 

HANGFIRE. -The detonation of an explosive charge at a time after 

its designed firing time. A source of serious accidents. 

HEADING. -A horizontal excavation driven in an underground mine. 

HERCUDET. -See gas detonation system. 

HERTZ. -A term used to express the frequency of ground vibrations 

and airblast. One hertz is one cycle per second. 

HIGH EXPLOSIVE. -Any product used in blasting which is sensitive 

to a No. 8 test blasting cap and reacts at a speed faster than that 

of sound in the explosive medium. A classification used by BATF for 

explosive storage. 

HIGHWALL. -The bench, bluff or ledge on the edge of a surface 

excavation. This term is most commonly used in coal strip mining. 

183 
Glossary 

IGNITACORD. -A cordlike fuse that burns progressively along its 

length with an external flame at the zone of burning and is used for lighting a series of safety fuses in sequence. Burns with a spitting flame similar to a Fourth-of-July sparkler. 

IME. -The Institute of Makers of Explosives. A trade organization dealing with the use of explosives, concerned with safety in manufacture, transportation, storage, handling and use. The !ME publishes a series of blasting safety pamphlets. 

INITIATION. -The act of detonating a high explosive by means of a 

cap, a mechanical device, or other means. Also the act of detonating the initiator. 

INSTANTANEOUS DETONATOR. -A detonator that contains no delay element. 

JET LOADER. -A system for loading AN-FO into small blastholes in which the AN-FO is drawn from a container by the venturi principle and blown into the hole at high velocity through a semiconductive loading hose. 

JOINTS. -Planes within a rock mass along which there is no resistance to separation and along which there has been no relative movement of the material on either side. Joints occur in sets, the planes of which may be mutually perpendicular. Joints are often called partings. 

JUMBO. -A machine designed to contain two or more mounted drilling units that may or may not be operated independently. 

KERF. -A slot cut in a coal or soft rock face by a mechanical cutter to provide a free face for blasti_ng. 

LEAD WIRE. -The wire connecting the electrical power source with the leg wires or connecting wires of a blasting circuit. Also called firing line. 

LEDC. -Low energy detonating cord, which may be used to initiate nonelectric blasting caps. 

LEG WIRES. -Wire connected to the bridge 

cap and extending from the waterproof plug. used to connect the cap into a circuit. 

of an electric blasting The opposite ends are 

LIFTERS. -The bottom holes in a tunnel or drift round. 

184 
Glossary 

LINE DRILLING. -A Method of overbreak control in which a series 

of very closely spaced holes are drilled at the perimeter of the 

excavation. These holes are not loaded with explosive. 

LIQUID OXYGEN EXPLOSIVE. -A high explosive made by soaking cartridges of carbonaceous materials in liquid oxygen. This 

explosive is rarely used today. 

LOADING DENSITY. -An expression of explosive density in terms of 

pounds of explosive per foot of charge of a specific diameter. 

LOADING FACTOR. -See powder factor. 

LOADING POLE. -A pole made of nonsparking material, used to push explosive cartridges into a borehole and to break and tightly pack the explosive cartridges into the hole. 

LOW EXPLOSIVE. -An explosive in which the speed of reaction is 

slower than the speed of sound, such as black powder. A 

classification used by BATF for explosive storage. 

LOX. -See liquid oxygen explosive. 

MAGAZINE. -A building, structure, or container specially constructed for storing explosives, blasting agents, detonators, or 

other explosive materials. 

MAT. -A covering placed over a shot to hold down flying material; usually made of woven wire cable, rope, or scrap tires. 

MAXIMUM FIRING CURRENT. -The highest current (amperage) recommended for the safe and effective performance of an electric 

blasting cap. 

METALLIZED. -Sensitized or energized with finely divided metal 

flakes, po~Yders, or granules, usually aluminum. 

MICHIGAN CUT. -See parallel hole cut. 

MICROBALLOONS. -Tiny hollow spheres of glass or plastic which are 

added to explosive materials to enhance sensitivity by assuring an 

adequate content of entrapped air. 

MILLISECOND. -The unit of measurement of short delay intervals, equal to 1/1000 of a second. 

MILLISECOND DELAY CAPS. -Delay detonators that have built-in time 

delays of various lengths. The interval between the delays at the 

lower end of the series is usually 25 ms. The interval between 

delays at the upper end of the series may be 100 to 300 ms. 

185 
Glossary 

MINIMUM FIRING CURRENT. -The lowest current (amperage) that will 

initiate an electric blasting cap within a specified short interval 

of time. 

MISFIRE. -A charge, or part of a charge, which for any reason has 

failed to fire as planned. All misfires are dangerous. 

MONOMETHYLAMINENITRATE. -A compound used to sensitize some water 

gels. 

MS CONNECTOR. -A device used as a delay in a detonating cord 

circuit connecting one hole in the circuit with another or one row 

of holes to other rows of holes. 

MHSA. -The Mine Safety and Health Administration. An agency under 

the Department of Labor which enforces health and safety regulations in the mining industry. 

MUCKPILE. -A pile of broken rock or dirt that is to be loaded for 

removal. 

MUD CAP. -Referred to also as adobe, bulldoze, blistering, or 

plaster shot. A charge of explosive fired in contact with the 

surface of a rock, usually covered with a quantity of mud, wet 

earth, or similar substance. No borehole is used. 

MULTIMETER. -(More properly called blasters' multimeter.) A 

multipurpose test instrument used to check line voltages, firing circuits, current leakage, stray currents, and other measurements 

pertinent to electric blasting. Only a meter specifically designated as a blasters' multimeter or blasters' galvanometer should be used to test electric blasting circuits. 

NATIONAL FIRE PROTECTION ASSOCIATION (NFPA) . -government association that publishes standards 

material and ammonium nitrate. 

-An industry 

for explosive 

NITROCARBONITRATE. -A classification once given to a blasting 

agent by DOT for shipping purposes. This term is now obsolete. 

NITROGEN OXIDES. -Poisonous gases created by detonating explosive materials. Excessive nitrogen oxides may be caused by an excessive 

amount of oxygen in the explosive mixture (excessive oxidizer), or 

by inefficient detonation. 

NITROGLYCERIN (NG). -The explosive oil originally used as the 

sensitizer in dynamites, represented by the formula C3H5 (0N0 2 ) 3 • 

NITROME'IHANE. -A liquid compound used as a fuel in two-component (binary) explosives and as rocket fuel. 

186 
Glossary 

NITROPROPANE. -A liquid fuel that can be combined with pulverized 

ammonium nitrate prills to make a dense blasting mixture. 

NITROSTARCH. -A solid explosive, similar to nitroglycerin in 

function, used as the base of "nonheadache" powders. 

NONEL. -See shock tube systen. 

NONELECTRIC DELAY BLASTING CAP. -A detonator with a delay 

element, capable of being initiated nonelectrically. See shock tube 

system; gas detonation system; Detaline System. 

NO. 8 TEST BLASTING CAP. -See test blasting cap No. 8. 

OSHA. -The Occupational Safety and Health Administration. An 

agency under the Department of Labor which enforces health and 

safety regulations in the construction industry, including blasting. 

OSMRE. -The Office of Surface Mining Reclamation and Enforcement. 

An agency under the Department of Interior which enforces surface 

environmental regulations in the coal mining industry. 

OVERBREAK. -Excessive breakage of rock beyond the desired 

excavation limit. 

OVERBURDEN. -Worthless material lying on top of a deposit of 

useful materials. Overburden often refers to dirt or gravel, but 

can be rock, such as shale over limestone or shale and limestone 

over coal. 

OVERDRIVE. -The act of inducing a velocity higher than the steady 

state velocity in a powder column by the use of a powerful primer. 

Overdrive is a temporary phenomenon and the powder quickly ass-umes 

its steady state velocity. 

OXIDES OF NITROGEN. -See nitrogen oxides. 

OXIDIZER. -An ingredient in an explosive or blasting agent which 

supplies oxygen to combine with the fuel to form gaseous or solid 

products of detonation. Ammonium nitrate is the most common 

oxidizer used in commercial explosives. 

OXYGEN BALANCE. -A state of equilibrium in a mixture of fuels and 

oxidizers at which the gaseous products of detonation are 

predominately carbon dioxide, water vapor (steam), and free 

nitrogen. A mixture containing excess oxygen has a positive oxygen 

balance. One with excess fuel has a negative oxygen balance. 

187 
Glossary 

PARAlLEL CIRCUIT. -A circuit in which two wires, called bus 

wires, extended from the lead wire. One leg wire from each cap in 

the circuit is hooked to each of the bus wires. 

PARAlLEL HOLE CUT. -A group of parallel holes, some of which are 

loaded with explosives, used to establish a free face in tunnel or 

heading blasting. One or more of. the unloaded holes may be larger than the blastholes. Also called Coromant, Cornish, burn, shatter, 

or Michigan cut. 

PARALLEL SERIES CIRCUIT. -Similar to a parallel circuit, but 

involving two or more series of electric blasting caps. One end of 

each series of caps is connected to each of the bus wires. 

Sometimes called series-in-?arallel circuit. 

PARTICLE VELOCITY. -A measure of ground vibration. Describes the 

velocity at which a particle of ground vibrates when excited by a 

seismic wave. 

PATTERN. -A plan of holes laid out on a face or bench which are 

to be drilled for blasting. Burden and spacing dimensions are 

usually expressed in feet. 

PELLET POWDER. -Black powder pressed into 2-in-long, 1\-in to 

2-in diameter cylindrical pellets. 

PENTAERY'DIRITOLTETRANITRATE (PEIN). -A military explosive compound used as the core load of detonating cord and the base 

charge of blasting caps. 

PENTOLITE. -A mixture of PEIN and TNT which, when cast, is used 

as a cast primer. 

PERMISSIBLE. -A machine, material, apparatus, or device that has 

been investigated, tested and approved by the Bureau of Mines or 

MSHA, and is maintained in permissible condition (MSHA). 

PERMISSIBLE BLASTING. -Blasting according to MSHA regulations for 

underground coal mines or other gassy underground mines. 

PERMISSIBLE EXPLOSIVES. -Explosives that have been approved by MSHA for use in underground coal mines or other gassy mines. 

PEIN. -See pentaerythritoltetranitrate. 

PLACARDS. -Signs placed on vehicles transporting hazardous 

materials, including explosives, indicating the nature of the cargo. 

PLASTER SHOT. -See mud cap. 

188 
Glossary 

PNEUMATIC LOADER. -One of a variety of machines, powered by 

compressed air, used to load blasting agents or cartridged water 

gels. 

POWDER. -Any solid explosive. 

POWDER CHEST. -A substantial, 

equipped with a lid and used 

storage of explosives. 

nonconductive portable container 

at blasting sites for temporary 

POWDER FACTOR. -A ratio between the anount of powder loaded and 

the amount of rock broken, usually expressed as pounds per ton or 

pounds per cubic yard. In some cases, the reciprocals of these 

terms are used. 

PREBLAST SURVEY. -A documentation of the existing condition of a 

structure. The survey is used to determine whether subsequent blasting causes damage to the structure. 

PREMATURE. -A charge that detonates before it is intended. 

Prematures can be hazardous. 

PRESHEARING. -See presplitting. 

PRESPLITTING. -A form of controlled blasting charges are fired in closely spaced holes at 

excavation. A presplit blast is fired before 

called preshearing. 

in which decoupled the perimeter of the 

the main blast. Also 

PRESSURE VESSEL. -A system for loading AN-FO into small diameter 

blastholes. The AN-FO is contained in a sealed vessel, to which air 

pressure is applied, forcing the AN-FO through a semiconductive 

hose and into the blasthole. Also known as a pressure pot. 

PRilL. -In blasting, a small porous sphere of ammonium nitrate 

capable of absorbing more than 6 pet. by weight of fuel oil. 

Blasting prills have a bulk density of 0.80 to 0.85 g/cu em. 

PRIMARY BLAST. -The main blast executed to sustain production. 

PRIMARY EXPLOSIVE. -An explosive or explosive mixture, sensitive 

to spark, flame, impact or friction, used in a detonator to 

initiate the explosion. 

PRIMER. -A unit, package, or cartridge of cap sensitive explosive used to initiate other explosives or blasting agents and which 

contains a detonator (MSHA). 

PROPAGATION. -The detonation of explosive charges by an impulse from a nearby explosive charge. 

189 
Glossary 

PROPAGATION BLASTING. -The use of closely spaced, sensitive 

charges. The shock from the first charge propagates t~ough the 

ground, setting off the adjacent charge, and so on. Only one 

detonator is required. Pr~rily used for ditching in damp ground. 

PROPELLANT EXPLOSIVE. -An explosive that normally deflagrates and 

is used for propulsion. 

PULL. -The quantity of rock or length of advance excavated by a 

blast round. 

RADIOFREQUENCY ENERGY. -Electrical energy traveling through the 

air as radio or electromagnetic waves. Under ideal conditions, this 

energy can fire an electric blasting cap. !ME Pamphlet No. 20 

recommends safe distances from transmitters to electric blasting 

caps. 

RADIOFREQUENCY TRANSMITTER. -An electric device, such as a 

stationary or mobile radio transmitting station, which transmits a 

radiofrequency wave. 

RDX. -Cyc.lotrimethy~enetrinitramine, an explosive substance used 

in the manufacture of compositions B, C-3 and C-4. Composition B is 

useful as a cast primer. 

RELIEVERS. -In a heading round, holes adjacent to the cut holes, 

used to expand the opening ~de by the cut holes. 

RIB HOLES. -The holes at the sides of a tunnel or drift round, 

which determine the width of the opening. 

RIP RAP. -Coarse rocks used for river bank or dam stabilization 

to reduce erosion by water flow. 

ROTATIONAL FIRING. -A delay blasting system in which each charge 

successively displaces its burden into a void created by an 

explosive detonated on an earlier delay period. 

ROUND. -A group or set of blastholes required to produce a unit 

of advance in underground headings or tunnels. 

SAFETY FUSE. -A core of potassium nitrate black powder, enclosed 

in a covering of textile and waterproofing, which is used to 

initiate a blasting cap or a black powder charge. Safety fuse burns 

at a continuous, uniform rate. 

190 
Glossary 

SCALED DISTANCE. -A ratio used to predict ground vibrations. As 

commonly used in blasting, scaled distance equals the distance from 

the blast to the point of concern, in feet, divided by the square root of the charge weight of explosive per delay, in pounds. 

Normally, when using the equation, the delay period must be at 

least 9 ms. 

SECONDARY BLASTING. -Using explosives to break boulders or high bottom resulting from the primary blast. 

SEISMJGRAPH. -An instrument that measures and may supply a 

permanent record of earthborne vibrations induced by earthquakes or 

blasting. 

SEMICONDUCTIVE HOSE. -A hose, used for pneur.Jatic loading of 

AN-FO, which has a minimum electrical resistance of 1,000 ohms/ft 

and 10,000 ohms total resistance and a maximum total resistance of 

2,000,000 ohms. 

SENSITIVENESS. -A measure of an explosive's ability to propagate 

a detonation. 

SENSITIVITY. -A measure of an explosive's susceptibility to 

detonation upon receiving an external impulse such as impact, shock, flame, or friction. 

SENSITIZER. -An ingredient used in explosive compounds to promote greater ease in initiation or propagation of the detonation 

reaction. 

SEQUENTIAL BLASTING MACHINE. -A series of condenser discharge blasting machines in a single unit which can be activated at 

various accurately timed intervals following the application of 

electrical current. 

SERIES CIRCUIT. -A circuit of electric blasting caps in which 

each leg wire of a cap is connected to a leg wire from the adjacent 

caps so that the electrical current follows a single path through the entire circuit. 

SERIES-IN-PARALLEL CIRCUIT. -See parallel series circuit. 

SHATTER CUT. -See parallel hole cut. 

SHELF LIFE. -The length of time for which an explosive can be 

stored without losing its efficient performance characteristics. 

SHOCK ENERGY. -The shattering force of an explosive caused by the 

detonation wave. 

191 
Glossary 

SHOCK TUBE SYSTEM. -A system for initiating caps in Which the 

energy is transmitted to the cap by means of a shock wave inside a 

hollow plastic tube. 

SHOCK WAVE. -A pressure pulse that propagates at supersonic velocity. 

SHOT. -See blast. 

SHOT FIRER. -Also referred to as the shooter. The person who actually fires a blast. A powde~~. on the other hand, may charge or load blastholes with explosives but may not fire the blast • 

. SHUNT. -A piece of metal or metal foil which short circuits the ends of cap leg wires to prevent stray currents from causing accidental detonation of the cap. 

SILVER CHLORIDE CELL. -A low-current 

galvanometer and other devices used 

electric blasti~~ caps and circuits. 

cell used in a blasting 

to measure continuity in 

SLURRY. -An aqueous solution of amnonium nitrate, sensitized with 

a fuel, thickened, and crosslinked to provide a gelatinous consistency. Sometimes called a ~mter gel. DOT may classify a slurry as a Class A explosive, a Class B explosive, or a blasting agent. An explosive or blasting agffi1t containi~ substantial portions of water (MSHA). See emulsion; water gel. 

SMOOTH BLASTING. -A method of controlled 

underground, in which a series of closely spaced at the perimeter, loaded with decoupled charges, highest delay period of the blast round. 

blasting, used 

holes is drilled 

and fired on the 

SNAKE HOLE. -A borehole drilled slightly into the floor of a quarry face. Also, boulder. 

downward from horizontal 

a hole drilled under a 

SODIUM NITRATE. -An oxidizer used in dynamites and sometimes in blasting agents. 

SPACING. -The distance bet~veen boreholes or charges in a row, measured perpendicular to the burden and parallel to the free face of expected rock movement. 

SPECIFIC GRAVITY. -The ratio of the ~reight of a given volume of 

any substance to the weight of an equal volume of water. 

SPLITTER CORD. -See Ignitacord. 

SPRINGING. -See chamberi~. 

192 

0 
Glossary 

SQUARE PATTERN. -A pattern of blastholes in which the holes in 

succeeding rows are drilled directly behind the holes in the front 

row. In a truly square pattern the burden and spacing are equal. 

SQUIB. -A fire device that burns with a flash. Used to ignite black powder or pellet powder. 

STABILITY. -The ability of an explosive ~terial to maintain its physical and chemical properties over a period of time in storage. 

STAGGERED PATTERN. -A pattern of blastholes in which holes in each row are drilled between the holes in the preceding row. 

STATIC ELECTRICITY. -Electrical energy stored on a person or object in a manner similar to that of a capacitor. Static electricity n~y be discharged into electrical initiators, thereby detonating them. 

STEADY STATE VELOCITY. -The characteristic 

specific velocity, under specific conditions, diameter, will detonate. 

velocity at which a 

in a given charge 

STE21MING. -The inert material, such as drill cuttings, used in the collar portion (or elsewhere) of a blasthole to confine the 

gaseous products of detonation. Also, the length of blasthole left uncharged. 

STICK COUNT. -See cartridge count. 

STRAY CURRENT. -Current flowing outside its no~l conductor. A result of defective insulation, it may come from electrical equipment, electrified fences, electric railways, or similar items. Flow is facilitated by conductive paths such as pipelines and wet ground or other wet materials. Galvanic action of two dissimilar metals, in contact or connected by a conductor, nay cause stray current. 

STRENGTH. -A property of an explosive described in various terms such as cartridge or weight strength, seismic strength, shock or bubble energy, crater strength, ballistic mortar strength, etc. Not 

a well-defined property. Used to express an explosive's capacity to do work. 

STRING LOADING. -The procedure of loading cartridges end to end in a borehole without deforming them. Used mainly in controlled blasting and permissible blasting. 

SUBDRILL. -To drill blastholes beyond the planned grade lines or below floor level to insure breakage to the planned grade or floor level. 

SUBSONIC. -Slower than the speed of sound. 

193 
Glossary 

SUPERSONIC. -Faster than the speed of sound. 

SWELL FACTOR. -The ratio of the volume of a material in its solid 

state to that when broken. May also be expressed as the reciprocal 

of this number. 

SYMPATHEIIC PROPAGATION (SYMPATHEIIC DEI'ONATION). - Detonation of 

an explosive material by means of an impulse from another 

detonation through air, earth or water. 

TAMPING. -The process of compressing the stemming or explosive in 

a blasthole. Sometimes ~sed synonymously with stemming. · 

TAMPING BAG. -A cylindrical bag containing stemming material, 

used to confine explosive charges in boreholes. 

TAMPING POLE. -See loading pole. 

TEST BLASTING CAP NO. 8. -A detonator containing 0.40 to 0.45 g 

of PETN base charge at a specific gravity of 1.4 g/cu em, and 

primed with standard weights of primer, depending on the 

manufacturer. 

TOE. -The burden or distance between the bottom of a borehole and 

the vertical free face of a bench in an excavation. Also the rock 

left unbroken at the foot of a quarry blast. 

TRANSIENT VELOCITY. -A velocity, different from the steady state 

velocity, which a primer imparts to a column of powder. 

TRINITROTOUJENE (TNT). -A military explosive compound used 

industrially as a sensitizer for slurries and as an ingredient in 

pentolite and composition B. Once used as a free-running pelletized 

powder. 

TRUNKLINE. -A detonating cord line used to connect the downlines 

or other detonating cord lines in a blast pattern. Usually runs 

along each row of blastholes. 

TUNNEL. -A horizontal underground passage. 

ThiO-COMPONENT EXPLOSIVE. -See binary explosive. 

UNCONFINED DEI'ONATION VELOCITY. -The detonation velocity of an 

explosive material not confined by a borehole or other confined 

medium. 

194 
Glossary 

V-CUT. -A cut employing several pairs of angled holes, meeting at 

the bottoms, used to create free faces for the rest of the blast 

round. 

VELOCITY. -The rate at which the detonation wave travels through 

an explosive. May be measured confined or unconfined. 

Manufacturer's data are sometimes measured with explosives confined 

in a steel pipe. 

VENTIJRI lOADER. -See jet loader. 

VOLUME STRENGTH. -See cartridge strength or bulk strength. 

WATER GEL. -An aqueous solution of arrrnonium nitrate, sensitized 

with a fuel, thickened, and crosslinked to provide a gelatinous 

consistency. Also called a slurry. May be an explosive or a 

blasting agent. 

WATER RESISTANCE. -A qualitative ~easure of the ability of an 

explosive or blasting agent to withstand exposure of l<ater liithout 

becoming deteriorated or desensitized. 

WATER STEMMING BAGS. -Plastic bags containing a self-seaHng 

device, which are filled with lvater. Classified as a perr.lissible 

stemming device by MSHA. 

v/EIGHT STRENGTH. -A rating that compares the strength of a given weight of explosive with an equivalent weight of straight 

nitroglycerin dynamite, or other explosive standard, expressed as a 

percentage. 

195 
APPENDIX 'D' 

BIBLIOGRAPHY 
BIBLIOGRAPHY 

Recorrrnended publications: 

1. U.S. Government: Laws and Regulations: 

Public Law 95-87 (30 USC 1201 et seq.) 

30 CFR 816 et seq. 

2. U.S. Department of the Interior, Bureau of Mines: 

Bulletin 656: "Blasting Vibrations and 

Structures", 1971. Harry R. Nicholls, Charles F. 

I. Duvall. 

Their Effects on 

Johnson and l<ilbu= 

Information Circular 8925: "Explosives and Blasting Procedures Manual", 1983. Richard A. Dick, Larry R. Fletcher, and Dennis V. D'Andrea. 

Report of Investigations 8485: "Structure Response <md Damage Produced by Airblast From Surface Mining", 1980. David E. Siskind, Virgil J. Stachura, Mark S. Stagg and John H. Kopp. 

Report of Investigations 8506: 

Ground Vibrations and Seismograph Stagg and Alvin J. Engler. 

''Measurement of 

Calibration", 

Blast 

1980. 

Induced 

Mark S. 

Report of Investigations 8507: "Structure Response and Damage 

Produced by Ground Vibration From Surface Mine Blasting", 1980. David E. Siskind, M.S. Stagg, J.W. Kopp, and C.H. Dowding. 

Report of Investigations 8508: "Airblast Instrumentation and Measurement Techniques for Surface Mine Blasting", 1981. Virgil J. Stachura, David E. Siskind and Alvin J. Engler. 

199 
-----------------------------~ 

Bibliography 

Report of Investigations 8896: "Effects of 

a 1-lood-Frane House", 1984. Mark S. Stagg, 

Michael G. Stevens and Charles H. Dowding. 

Repeated Blasting on 

David E. Siskind, 

3. ATF P 5400.7 (11/82): "ATF Explosives Law and Regulations", 

1982. 

4. Independent publications and reports: 

"Blaster's Handbook" 16th Edition, 1980. 

Division, E.I. Du Pont de Nemours & Co., 

Delaware, 19898. 

Explosives Products 

(Inc.), Wilmington, 

"Blaster's Handbook" 6th Edition, 1968. Canadian Industries 

Limited, Explosives Division, Montreal, Quebec, Canada. 

"Blasting Operations", Gary B. Hemphill, 1981. McGraw-Hill Inc. 

"Blasting Technique", R1.me Gustafsson, 1981. Dynamit-Nobel, 

\Vien. 

"Blast Vibration Analysis", G.A. Bollinger, 1971. Southern 

Illinois University Press, Carbondale, Illinois, 62901. 

"Blast Vibration Monitoring & Control", C.H. Dmvding, 1985. 

Prentice-Hall, Englewood Cliffs, N.J. 

"Control of Vibration and Blast Noise 

Mining." Vols. I to IV, December 1978. \Viss, 

Associates, Inc, Northbrook, IL. Report to 

J0255022. NTIS PB-299 887. 

from Surface Coal 

Janney, Elstner and 

USBH, Contract No. 

"The Developnent of Rational Damage Criteria for Low-Rise 

Structures Subjected to Blasting Vibrations", August 1976. Kenneth 

Medearis (Kenneth Medearis A9sociates), Final Report to Crushed 

Stone Association, lvashington, D.C. 

200 
Bibliography 

"Geologic Factors Affecting Vibration from Surface Mine 

Blasting", Final Report to USB!1, T!,rin Cities. Contract H.0222009: 

September 1985. Vibra-Tech Engineers, Hazleton, Pennsylvania. 

"The Modern Technique of Rock Blasting", U. I..angefors & B.A. 

Kihlstrom, 1963. John Hiley & Sons, Inc. N.Y. 

5. Citizen Interests: 

"Blasting Damage- A Guide for Adjusters & Engineers", 2nd 

Edition, 1972. Claims Bureau, Engineering and Safety Service and 

Property Claim Services of American Insurance Association. 

"Strip Mine BlasUng", Albert Fritsch, Dennis Darcey, Gerard 

McMahon, Elaine Bmn1s & Brian Ulrickson, 1977. Center for Science 

in the Public Interest, Hashington, D.C. 

"Citizens' Blasting Handbook", Mark L. Morgan, Albert J. Fritsch, 1978. Appalachia-Science in the 

Corbin, KY. 

11-U.S, GOVERNMENT PRINTING OFFICE: 1987 774-613/65093 

201 

Edwin A. Moss & 

Public Interest,