Materials Classes

Granulation requirements specify that Class 1 material shall be furnished in lump form, while Class 2 and 3 material shall comply with the following, using US Standard sieves ... 

The requirements of the US Armed Forces are described in Military Specification MIL A-166C (6 January 1975) entitled, Ammonium Picrate (Explosive D) It covers one grade of material, representing two classes with respect to granulation. Class 1 material (coarse) is intended for use in the press-loading of shells, while Class 2 (fine) is used for the manuf of Picratol and other compns. The requirements are as follows ... 

This spec covers one grade of EtCell but two classes Class 1 is of high viscosity, while Class 2 is of low viscosity. Class 1 material shall fuse without charring and be capable of being drawn into a thread at a temperature not lower than 145°C, when tested as specified in opn 8... 

Thermoplastic Point, Class 1 material shall fuse without charring and be capable of being drawn into a thread at a temp not lower than 145°C... 

Copper (a Class 1 material) showed no observable expansion of vapors during the phase when main sequence was followed. Tungsten, on the other hand, showed appreciable expansion of vapors after the onset of vaporization and before the end of vaporization... 

Infrared-sensitive films and plates may be divided into two classes (1) materials of relatively high speed to the extreme red and infrared,... 

Class 1 materials remaining from production by the manufacturing or converting industry where their history is well known. These materials typically are always under the control of the processor. Provided that good manufacturing practice is followed and contamination can be excluded, this material is as suitable for direct contact with foodstuffs as new material. Class 1 material can be defined as post-industrial recycled polymers and corresponds to US FDA s primary recycling (pre-consumer scrap). 

With respect to the more problematic dumping activities it was decided by the Definitive Policy Plan of the Netherlands (1982) that of the dredged sludge from Rotterdam harbour only class 1 material from the western harbour area, which is primarily of marine origin, is permitted for disposal in the sea at the Loswal Noord site (approx. 13 million m per year). 

Not smoke or cany a lighted cigarette, cigar, etc. within 7.6 m. (25 ft.) of an empty tank which contained Class 3 or Division 2.1 materials or a vehicle which contains Class 1 materials. Class 5 materials, or flammable materials in Class 3 or Divisions 2.1, 4.1, and 4.2 ... 

Offering a Class 1 material that is fitted with its own means of ignition or initiation, without providing protection from accidental actuation. 173.60(b)(5) 15,000. 

This does not apply to Class 1 materials, Class 7 materials, or non-bulk packagings for which identification numbers are not required (such as limited quantities or ORM-D). 

ASTM E185-82 also provides the option of including correlation monitor material in the capsules. Correlation monitor material provides an independent check on the irradiation conditions because other specimens of the same correlation monitor material have been irradiated in other reactors and its response to irradiation (embrittlement characteristics) is well documented. An example of a common correlation monitor is Heavy Section Steel Technology (HSST) Plate 02 (an SA533 Grade B, Class 1 material). Correlation monitor material is also included in the surveillance program to provide a means of validating neutron fluence estimates for the surveillance capsules. The data obtained from correlation monitors should... 

The U.S. Department of Transportation organizes explosives to follow the Globally Harmonized System (GHS) of classifying chemicals (see Chapter 24). Explosives are Class 1 materials in the GHS definitions and further divided into Divisions. Table 17-4 lists the DOT and GHS Divisions for explosives. 

The Toxic Gas Model Ordinance requires all Class 1 gases to be contained in a process tube enclosed in a secondary containment tube. Class 1 materials are those with a material hazard index of greater than or equal to 500,000, or that carry a US Department of Transportation classification of Poison A. (Note The Department of Transportation no longer uses the Poison A classification, and there is no direct replacement. Reference Code of Federal Regulations, Title 49, parts 172 and 173 for guidance). 

For purposes of transportation, explosives are regulated as DOT Class 1 materials. This class is further divided into six divisions corresponding to the hazardous properties of the materials. 

In Chapter 1 we suggested a control system structure in which most control loops are vided into three classes (1) material balance, (2) product quality, and (3) constraints. If we look at these loops from the standpoint of classic single-loop theory, we see that the material-balance loops function as low-pass filters (slow dynamics) while the product-quality loops function as bandpass or high-pass filters (faster dynamics). 

The specifications for ammonium picrate cover one grade of material representing two classes with respect to granulation. Class 1 material, which is the coarser of the two classes, is intended for use in the... 

Current interest in DNAN is predominantly as an ingredient in explosive formulations because it is a less-sensitive melt-cast medium than TNT, and it is categorized as a Class 4.1 Flammable Solid and is therefore subject to less stringent international transportation requirements than Class 1 materials. Exposure to DNAN via oral intake, skin absorption, and inhalation is more acutely toxic than that of TNT for a single dose for a single exposure. Some of its properties are presented in Table 2.24. 

Class 2. Quaternary ammonium/carboxylic acids. These materials contain a permanent cationic site (-N Rs) as well as the carboxyl group. At low pH they will, of course, be cationic. At slightly alkaline pH they will become isoelectric and remain so. They can never become anionic in the way that the class 1 materials can. 

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