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Excavations and trenches are among the most hazardous operations in construction. A cubic yard of soil weighs approximately 2,700-3,000 lbs - a cave-in can be immediately fatal. No worker enters any trench or excavation 5 feet or deeper without a protective system in place.

Per 29 CFR 1926.652 Appendix A:

When in doubt, classify as Type C - the most conservative, most protective.

Maximum slopes for workers in excavation:

Benching only permitted in Type A and Type B soil - never in Type C.

Designated Competent Person for Excavation: _______________

Torch-applied roofing (modified bitumen application using open-flame propane torches) is one of the highest fire-risk activities in the roofing trade. Oregon's wildfire season (July-October) further elevates torch fire risk when ambient conditions are dry. Demo Company LLC treats torch operations as a high-risk activity requiring strict pre-work controls and dedicated fire watch at all times.

Before igniting any torch, the supervisor confirms:

• Hot work permit issued (if required by building owner or GC - see Section 9.4)
• Fire watch person designated, present, and briefed
• Fire extinguishers (minimum 10-lb ABC dry chemical) placed within 30 feet of the work - minimum two extinguishers for torch work
• Combustible roofing debris cleared from a minimum 35-foot radius of torch work area
• Combustible material on walls, parapets, and curbs protected or removed
• Propane hose connections inspected for leaks using soapy water solution (never use flame)
• Propane cylinder stored upright and secured
• Cylinders not used as a torch rest, seat, or step
• All workers in the area notified of torch work
• During wildfire season (July-October): AQI checked; no torch if AQI >=151 without supervisor approval

• A designated fire watch person remains on the roof during all torch operations
• Fire watch continues for at least 30 minutes after the last flame application - monitoring for smoldering or delayed ignition
• Fire watch duties are exclusive - no other work while serving as fire watch

The following minimum distances must be maintained from energized overhead power lines (including insulated lines - assume insulated lines are energized):

Distribution lines (residential/light commercial) are typically 4kV-35kV -> 10-foot minimum distance applies. When voltage is unknown: maintain 10-foot minimum or contact utility for voltage identification.

In addition to federal OSHA distances above, Texas has its own overhead power line statute that imposes separate obligations:

Tex. H&S Code Ch. 752 (Secs. 752.001-752.008) - High Voltage Overhead Lines:

1. 6-foot trigger distance: No person may operate equipment, use tools, or handle materials within 6 feet of a high-voltage overhead line (>600V) without complying with Ch. 752
2. 48-hour advance notification: Before performing any work that will bring a person, tool, or material within 6 feet of a high-voltage overhead line, the responsible party must notify the line operator at least 48 hours in advance - this requirement has NO federal equivalent
3. "Authorized person" exemption: Employees of the line operator working on the line itself may be exempt; Demo Company LLC employees are not treated as exempt under Ch. 752 unless utility/operator status is confirmed in writing for that specific task
4. Penalties: Violation of Sec. 752.007 carries a fine of $100-$1,000 and/or jail up to one year (Class B misdemeanor). Additionally, Sec. 752.008 imposes joint-and-several civil liability for damages to the line operator plus reimbursement of repair costs.

Both the federal 10-foot MAD and the Texas 6-foot/48-hour notification apply simultaneously. Contractors must comply with whichever is more restrictive for the situation.

HVAC technicians use oxy-acetylene or air-acetylene torches for brazing copper refrigerant lines. Plumbers use propane or MAPP gas torches for soldering copper water lines. Both operations carry fire, fume, and thermal burn hazards.

• Inspect torch, hoses, regulators, and cylinders for damage, leaks, or deterioration before each use
• Check connections with approved leak detection solution - never use flame to check for leaks
• Keep fuel gas cylinders upright and secured when in use and in storage
• Protect hoses from damage, heat, and foot traffic; never allow torch to rest on or near hoses

• Ventilation: Provide adequate ventilation - brazing flux and silver brazing alloys generate fumes (zinc oxide, fluorides from flux, silver). Work outdoors or in well-ventilated areas whenever possible; use local exhaust ventilation in confined/enclosed spaces
• Fire prevention (T8 CCR Sec. 4848; NFPA 51B; 29 CFR 1926.352): Before torch work in any structure, inspect the work area for combustible materials within 35 feet. Wet down, remove, or shield combustibles that cannot be moved.
• Fire watch: A designated employee with a readily accessible fire extinguisher (minimum 10-lb ABC dry chemical) monitors the work area during brazing and for minimum 30 minutes after the torch is extinguished. Fire can smolder inside walls, insulation, and structural members long after visible flame is extinguished.
• Protect pipe insulation from torch heat - use heat shields/reflective material
• Do not braze or solder near refrigerant - refrigerant decomposed by heat produces phosgene and hydrofluoric acid fumes
• Phosphoric acid flux (for plumbing soft soldering): wear eye protection; avoid skin contact; flux fumes are irritating to eyes and respiratory tract

• Brazing goggles (shade 4-5) or face shield - protect eyes from UV and heat
• Leather welding gloves
• Long sleeves - heat-resistant clothing
• Leather apron for heavy brazing work
• Ventilate work area or use respiratory protection appropriate for fumes generated (see Section 23)