Tempered Safety Glass              

Phoenician Resort. Installer: A & J Glass Co.

Glasswerks manufactures tempered and heat strengthened glass to the highest established standards. This glass meets or exceeds the specifications as established by U.S. FEDERAL STANDARDS CPSC 16 CFR 1201 and complies with ANSI Z97.1. Tempered glass produces exceptional strength, thermal resistance and non-hazardous fracture patterns. The tempering process involves heating to about 1200 F. Followed by rapid cooling of the outer surfaces via controlled air blasts, the center is then allowed to cool slowly. This achieves a highly desirable state of surface compression, perfectly balanced by internal tension. This results in improved resistance to rapid temperature changes and impacts, plus a fracture pattern yielding small, relatively harmless fragments rather than hazardous jagged edges and shards. Horizontally tempered glass may contain slight surface waves caused by contact with the rollers. This waviness can be detected when viewing reflected images from a distance. A certain amount of warp or bow is associated with each piece of glass due to the heating and rapid cooling process. On occasion this will show up as distorted reflected images under certain viewing conditions, being more noticeable in reflective glass. These are inherent characteristics of tempered glass and are not defects.

            Glass Quality q3, Maximum Allowable Imperfections for Thickness 6.0 mm (1/4 in.) or Less A A

Imperfections	Up to 2.5 m2 (25ft2)		q3, Glazing Select Quality		Over 7.0 m2 (75 ft2)
			2.5 to 7.0 m2 (25 to 75 ft2)
	Central B	Outer B	Central B	Outer B	Central B	Outer B
Gaseous inclusions, maximum size c	1.6mm (1/16 in.) D,E	2.4mm (3/32 in.) D,E	3.2mm (1/8 in.) D,E	4.8.mm (3/16 in.) D,E	6.4mm (1/4 in.) D,E	6.4mm (1/4 in.) D,E
Open or translucent gaseous inclusions, maximum size c	1.2mm (3/64 in.) D,E	1.6mm (1/16 in.) D,E	1.2mm (3/64 in.) D,E	1.6mm (1/16 in.) D,E	6.4mm (1/4 in.) D,E	6.4mm (1/4 in.) D,E
Knots, dirt and stones, maximun size	0.4mm (1/64 in.) D	0.8mm (1/32 in.) D	1.6mm (1/16 in.) D	1.6mm (1/16 in.) D	3.2mm (1/8 in.) D	3.2mm (1/8 in.) D
Scratches and rubs (intensity)	medium G	medium G	medium G	heavy G	heavy G	heavy G
Crush (intensity, maximum length)	medium G <1.6mm (<1/16 in.) F	medium G <2.4mm (<3/32 in.) F	medium G <3.2mm (<1/8 in.) F	heavy G <4.8mm (<3/16 in.) F	heavy G <6.4mm (<1/4 in.) F	heavy G <6.4mm (<1/4 in.) F
Digs, maximum length	1.6mm (1/16 in.) F	2.4mm (3/32 in.) F	3.2mm (1/8 in.) D	4.8mm (3/16 in.) D	6.4mm (1/4 in.) D	6.4mm (1/4 in.) D
Ream, strings, lines, and other linear distortion (maximum angle or intensity)	45 0 H or medium		90 0 H or Heavy		90 0 H
Wave (intensity)	medium J	medium J	medium J	heavy J	heavy J	heavy J
Process surface imperfections (intensity)	medium K	medium K	medium K	heavy K	heavy K	heavy K

 

A  Greater than 6.0 mm (1/4" in.) in thickness may contain proportionally more and larger imperfections.

B  The central area is considered to form an oval or circle centered on the lite whose axes or diameter do   not exceeded 80% of the overall dimension. The remaining area is considered the outer area.

C  Gaseous inclusions, knots, dirt, and stones may be round or elongated. For elongated imperfections of    this type(s)  the maximum size specified shall be determined by adding the length and width of the  imperfection and dividing by two, for example (L+W)/2

D  Separated by at least 610 mm (24 in.).

E  For imperfections of a smaller size or of less intensity, the minimum separation shall be proportionately less.  The larger of the two imperfections shall govern the separation. Imperfections not specifically mentioned shall be compared to the imperfection they most closely resemble.

F  Separated by at least 610mm (24 in.).

G  Intensity (scratches, rubs, and crush) - When looking through the glass and perpendicular to it using daylight without sunlight or with background light suitable for observing each type of imperfection, the imperfections shall not be detectable at distances greater than the following, except for heavy intensity. Intensity    Distance Faint      203 mm (8 in.) Light     914 mm (36 in.) Medium      3.3 m (132 in.) Heavy   detected at distances greater than 3.3 m (132 in.)

H  Vision interference angle

I   Intensity (ream, string, lines, and other linear distortion) - When evaluating using the shadowgraph, the     intensities of these imperfections are defined as having a shadowgraph readout at distances greater     than or equal to the following: Intensity   Minimum Distance, mm (in.) Light    76 (3) Medium       51 (2) Heavy   25 (1)

J  Intensity (wave)- When evaluated using the shadowgraph, the intensities of wave are defined as having     shadowgraph readouts at distances greater than or equal to the following: Intensity Minimum Distance, mm (in.) Medium   254 (10) Heavy   152 (6)

K Intensity (process surface imperfections)- When viewed in normal reflected light, the imperfections are classified as follows: faint-visible only to the trained eye; light -just noticeable; medium-visible as a slight grayish haze; and heavy- readily visible as a cloudy surface.

* From ASTM C 1036.

Bow Allowance

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