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LST SAFETY. FRANK O’NEILL (SLAC) 10/21/03 . SAFETY ISSUES. Seismic Fire Electrical Environmental. SIESMIC SAFETY. ~10,000 kg of brass per sextant. Approval from Earthquake Safety Committee 10/17/03 . FIRE SAFETY ISSUES. Combustibility of LST material
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LST SAFETY FRANK O’NEILL (SLAC) 10/21/03
SAFETY ISSUES • Seismic • Fire • Electrical • Environmental
SIESMIC SAFETY • ~10,000 kg of brass per sextant. • Approval from Earthquake Safety Committee 10/17/03
FIRE SAFETY ISSUES • Combustibility of LST material • Flammable Component of Gas Mixture • Wire and Cable Fire Safety Rating
LST MATERIAL COMBUSTABILITY • LST extrusion is constructed of plastic (PVC) • Rated Class V-0 in accordance with UL-94 (Tests of Flammability of Plastic Materials) • Loaded with 20% Calcium Carbonate This provides the PVC with some fire retardant properties • Small scale laboratory fire tests were conducted by Hughes Associates • ASTM E-1354 “cone calorimeter” test • Comparison of RPC and LST samples
TEST RESULTS • The PVC material exhibited significantly better ignitability and heat release rate characteristics than the existing RPC material • The PVC has a strong tendency to intumesce resulting in an insulating layer that inhibits flame spread
GAS MIXTURE • 3 components: Argon, Isobutane, and CO2 • Similar Gas Mixtures utilized on other Detectors • SLD: 2.5% Ar, 9.5% isobutane, 88% CO2 • ZEUS: 3% Ar, 8% isobutane, 89% CO2 • Final decision on mixture pending • Nonflammable mixture will be utilized • Hughes Associates providing consulting services for evaluation of mixtures
Wire and Cable Fire Safety • High Voltage Cable meets the CERN, Safety Instruction 23 • Signal Cables meet the IEC 331-1 (Flame and Fire Propagation Test)
Electrical Safety • High Voltage • Passive over-current protection in power supplies • ~5500 Volts and ~1 nF a ~15 mJ. • Startle hazard • Low voltage • Read-out electronics in VME crates • Usual precautions such as fusing
ENVIRONMENTAL SAFETY • Bay Area Air Quality Management District (BAAQMD) issues SLAC a permit for discharge of VOCs • SLAC may need to modify the permit • Coordination with the SLAC Environmental Protection Department is ongoing