Quantity-distance

The hazard posed can be limited by maintaining a zone free of people and property around a storage area of explosive material. The minimum radius of the zone depends on the type and quantity of explosive, the extent and type of barrica ding, and the magnitude of loss that would be encountered if an explosive incident occurred. The maximum distance to which hazardous explosive effects propagate depends on the blast overpressure created, which as a first approximation is a function of the cube root of the explosive weight, W. This is termed the quantity distance and is defined as... 

Safety Manual , AMCR 385-100 (April 1970), 11-1 to 11-34, 17-1 to 17-35, 18-1 to 18-13 19-1 to 19-36 (Storage and handling of chemical agents and munitions quantity-distance tables storage of expls ammo quantity-distance classification and storage compatibility)... 

The numerical values of most physical quantities are expressed in terms of units. The distance between two points, for example, can be specified by the number of meters (or feet, Angstroms, etc.). Similarly, time cap be expressed in seconds, days or, say, years. However, the number of days per year varies from one year to another. The quantities, distance (length) and time, as well as mass, are usually chosen to be primary quantities. In terms of them Newton s second law for the force on an object, can be written as force = mass, distance/(time)2. The definition of the primary quantities allows dimensional expressions to be written, such as [force] — MLT-2 in the present example. Note, however, that in everyday life one speaks of the weight of an object (or a person). Of course the weight is not the mass, but rather the force acting on the object by the acceleration due to gravity [acceleration] = LT 2. 

Indeed it does, as can be shown by the fits made in Britain for bomb damage to houses, following World War II. These fits, illustrated in Fig. 17, now form part of the basis for the British Quantity-Distance tables for explosives safety. 

Freund, D., Origin and Subsequent Modification of Explosive Safety Quantity-Distance (ESQD) Standards Special Reference to Naval Weapons—Volume 1, DTNSRDC/SD-78-4, May 1978. 

Each state has its own regulations regarding distances. For instance, the table on p 810 of TM 9-1904, gives the Intraplant Quantity-Distance Table as prescribed by New Jersey State laws... 

Bombs and c omponents should be stored in an area set aside for this purpose. Such an area should be located at greater than missile distance from artillery ammo storage and removed from operating areas, inhabited areas and public highways railways. These distances are given in Quantity -Distance Table for classes 9 10, in Ref 5,pp 66 -7 and in Sect 7, Ref 7. The magazines must be fireproof... 

All the above-mentioned bldgs and other structures within US Ordnance establishments shall be located at such distances, one from the other, as prescribed by Quantity-Distance Tables given in Ref 2, seen 17 and Ref 3,pp 44-80... 

Storage (for every expl) Dry hazard class (quantity - distance) 9 and compatibility group ... 

Sensitivity classification (for quantity-distance storage). Class 7, formerly Class 9 (Ref AMC Safety Manual AMCR 385 224, change 12, p 17-63, 9 Nov 1964)... 

Refs 1) Anon, Ammunition and Explosives Standards , TM 9-1300-206 (1973), Chapt 5, pp 5-1 to 5-31 (Quantity-Distance Regulations, Classes and Tables) 2) C.E. Gregory, Explosives for North American Engineers , Trans Tech Publications, Cleveland (1973), 252—56 3) Anon, Ammunition and Explosives Safety Standards , AR 385-64 (1975)... 

On an industrial scale, operations are commonly carried out by remote control (Ref 10) and the considerations of quantity-distance (Ref 48) and barrier design (Refs 13 75) apply. On a lab scale, remote weighing, mixing and pressing are usually not practical, and the protection of personnel must take the form of shielding for eyes, face and hands, as well as thru protection for the hair and the choice of suitable clothing. 

Federal Register 41, (74), 15972—16131 (April 1976). Order as Publication of Docket HM-103/112, Amendments (Part II) from the Supt of Doc, Gov t Printing Office. Washington, DC 47) Anon, DOD Ammunition and Explosives Safety Standards , Publication DOD 5154.4 (Mar 1976) 48) Anon, Quantity-Distance... 

Table of Distances, American. See under Quantity-Distance Concepts in article entitled Safety in the Energetic Materials Field in this Vol... 

Hazards classification is the assignment of a material or an end item (in this case only in-process materials) to a particular hazard class which best describes the threat presented by the material. This requires the use of a hazards classification procedure which provides the guidelines and criteria on which the choice of the hazards class is based. The assigned hazards, class of the material is then used as the basis for selecting the proper quantity-distance relationship. Thus, if the hazards classification procedure erroneously assigns a material to the wrong class, either safety is compromised or excessive safety requirements are imposed. Both possibilities are expensive. 

Quantity-distances established to keep overpressure below window breakage level for inhabited buildings. 

Barricades, quantities, distances established to keep lethal fragments below a density of one per 600 sq ft at personnel location. 

The Safety Manual AMCR 385-100 prescribes general safety rules for the US Army Materiel Command including those relevant to facility construction for explosive materiel operations and storage requirements, personal protective clothing and equipment together with quantity distance standards of explosives. 

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