12.6 Work Zone Traffic Control, PPE, Fall Protection, Fire Extinguishers, First Aid & Bloodborne Pathogens

The hazards that happen outside the plant fence

WPI's collection outline lists configure traffic plans and set up signs for traffic control, monitor work and job site conditions to ensure the protection of workers, pedestrians, and vehicular traffic, and safety procedures for personal protection equipment (respiratory protection, safety glasses, gloves, hard hats, fall protection), fires (prevention, fire extinguishers), first aid, infectious diseases and bloodborne pathogen protection, and lifting. The distribution outline lists follow safety practices (traffic control, confined spaces, hazmat, lockout/tagout, excavation).

Work zone traffic control

Being struck by a vehicle is a leading cause of death in utility work. Colorado follows the Manual on Uniform Traffic Control Devices (MUTCD) and CDOT standards, which divide every work zone into the same five parts:

1. Advance warning area — signs telling drivers what to expect, at spacing based on approach speed.
2. Transition area — the taper where traffic shifts, delineated by channelizing devices.
3. Buffer space — longitudinal and lateral separation between traffic and the work. Nothing and no one occupies the buffer.
4. Work area — where the crew works, closed to traffic.
5. Termination area — a downstream taper returning traffic to normal, with an END ROAD WORK sign.

Practical requirements:

• Set up from the direction of oncoming traffic, and take down in the reverse order, removing devices from the far end first so the crew is never exposed downstream of an open lane.
• Taper length depends on speed and lane width; higher speeds need much longer tapers.
• High-visibility apparel meeting the applicable ANSI/ISEA class is worn by everyone in the zone, at night with retroreflective material.
• Flaggers are trained and certified, stand in an escape-route position, never in the traffic lane they are controlling, and use STOP/SLOW paddles rather than flags where practical.
• Night work requires lighting that does not blind approaching drivers, plus additional retroreflectivity.
• Pedestrian routes must be maintained, accessible, and separated from the work — a detoured sidewalk that dumps pedestrians into a traffic lane is a violation and a hazard.
• Vehicle positioning: park to shield the crew, use rotating or strobe beacons, and never back up without a spotter.

Personal protective equipment

PPE is the last line of defense, below elimination, substitution, engineering controls, and administrative controls in the hierarchy. It protects one person and only if it is worn, fits, and is maintained.

A dust mask is not respiratory protection for a gas or vapor. Chlorine, hydrogen sulfide, ammonia, and solvent vapors require an appropriate cartridge or supplied air, and an oxygen-deficient or IDLH atmosphere requires SCBA or a supplied-air respirator with escape bottle — never an air-purifying respirator.

Fall protection

Water and wastewater facilities are full of fall hazards: tank roofs and access ladders, clarifier walkways, open wet wells and manholes, basin edges during drain-down, and ladders into vaults.

• Guardrails, covers, and hole protection are the preferred engineering controls. An open manhole is guarded or attended at all times, never left open and unattended even briefly.
• Personal fall arrest uses a full body harness, a connector rated for the application, and an anchorage capable of the required load. Body belts are not acceptable for fall arrest.
• Anchor above the dorsal D-ring where possible, and calculate the fall clearance: free fall distance plus deceleration distance plus harness stretch plus a safety margin. On a short ladder or a low walkway, a lanyard may not have room to arrest before impact, which is why self-retracting lifelines are used in low-clearance situations.
• Rescue plan. Fall protection without a plan to retrieve a suspended worker is incomplete. Suspension trauma can be life threatening within minutes, so prompt rescue is part of the plan, not an afterthought.
• Ladders are inspected, set at the correct angle, extended three feet above the landing, and tied off.

Fire prevention and extinguishers

• Class A — ordinary combustibles. Class B — flammable liquids. Class C — energized electrical. Class D — combustible metals. Class K — cooking media.
• Most utility extinguishers are ABC dry chemical. Carbon dioxide units are used around electronics and control panels because they leave no residue.
• PASS: Pull the pin, Aim at the base of the fire, Squeeze the handle, Sweep side to side.
• Extinguishers are inspected monthly for pressure, access, and damage, and serviced annually.
• Fight a fire only if it is small and incipient, you have the right extinguisher, you are trained, you have a clear escape route at your back, and the fire is not growing. Otherwise evacuate and call.
• Utility-specific fire risks: methane and digester gas, hydrogen from onsite hypochlorite generation and from battery charging, oxidizers such as calcium hypochlorite and permanganate stored near organics, diesel and gasoline, and electrical faults in wet environments.

First aid and bloodborne pathogens

Wastewater work involves routine exposure to sewage, and the standard of care is straightforward:

• Hepatitis B vaccination is offered to employees with reasonably anticipated occupational exposure, and tetanus is kept current.
• Universal precautions: treat all blood and body fluids, and raw sewage, as potentially infectious.
• Hand hygiene before eating, drinking, smoking, or touching the face, and no eating or drinking in work areas.
• Cover cuts and abrasions with waterproof dressings before entering a work area.
• Wash and disinfect any exposure immediately, flush eyes at an eyewash for 15 minutes, and report every exposure incident so post-exposure evaluation can occur.
• Sharps are a real hazard in collection work; needles reach sewers, and puncture-resistant gloves and containers are used.
• Keep a stocked first aid kit and trained responders on each crew; CPR and first aid certification is standard.

Manual material handling

Back injury is the most common lost-time injury in utility work. Controls in order: eliminate the lift with a hoist, cart, or jib; reduce the load; team lift; then technique — load close to the body, feet apart, lift with the legs, no twisting, and clear the path before lifting.