MANAGING DEEP SHAFT RECUES

MANAGING DEEP SHAFT RECUES

BY LARRY COLLINS

“Deep shaft rescue” is an informal term used to describe confined-space rescue situations involving victims trapped in pipes, wells, and other vertical shafts–in essence, vertical, belowgrade confined spaces. The Occupational Safety and Health Administration (OSHA) defines a shaft as “any excavation more than 20 feet in depth whose depth to width ratio is 5 to 1 or greater.” Deep shaft includes all vertical mines; ventilation holes for subway systems; bore holes for deep pilings at construction sites; old wells; other vertical belowground passageways; and abandoned septic tanks, natural shafts, caves, sink holes, and any spaces that meet the five-to-one depth-to-width ratio, even if they are less than 20 feet in depth.

Safely managing deep shaft rescues frequently requires a mix of disciplines, including high-angle rope systems, emergency shoring, and mine and tunnel rescue techniques. If the shaft fills with water (a dire situation for anyone trapped below), dive rescue and/or swiftwater rescue techniques may also be required.

Deep shaft rescues generally involve confined spaces. The approaches to both types of incidents are similar, but in deep shaft rescues, extra measures should be taken to address fall hazards and other problems common to these incidents. Experienced, well-trained officers should directly supervise all operations. All personnel entering the so-called danger zone should be fully trained and equipped to deal with confined-space hazards. Strictly enforce standard confined-space entry procedures and safety precautions.

Applicable Regulations

OSHA recently approved regulations intended to provide an overall “umbrella of safety” for tunnel and shaft operations. Other, more stringent regulations vary from state to state. Some of the requirements contained in California Title 8, Industrial Relations, Division 1, Department of Industrial Relations, Chapter 4, Division of Industrial Safety, Subchapter 20, Tunnel Safety Orders, Article 10, Emergency Rescue Procedures and Equipment, for example, include the following:

“Rescue crews shall be qualified in rescue procedures, the use and limitations of breathing apparatus. Qualifications shall be reviewed not less than annually.”

“On job sites where flammable or poisonous gases are encountered or anticipated in hazardous quantities, rescue team members shall all practice donning and using SCBA monthly.”

“The employer shall ensure that rescue teams are familiar with the job site.”

“No person who is physically unfit or who has not had the required training shall be allowed to use permissible self-contained oxygen breathing apparatus for rescue work.”

“Where self-contained oxygen breathing apparatus is required … initial training for rescue crew members … shall be equivalent to 24 hours, and 8-hour refresher training shall be given at least every three months and shall include at least 2 hours in the wearing and use of SCBA.”

These are tough standards for many fire departments and rescue agencies to meet, yet they are necessary to ensure a reasonable level of safety during confined-space rescue operations.

Failure to comply with state and federal mine safety and confined-space regulations may result in citations or criminal prosecution. This is true also for decisions supervisors make under emergency conditions.

The threat of criminal prosecution for failure to follow standard worker safety law is quite real. For example, Article 6425 of the California Labor Code states that any supervisor who willfully violates the Health or Safety Standard, resulting in “employee death or impairment” may be fined up to $10,000 and imprisoned for six months. In one recent case, a construction project supervisor was criminally prosecuted after he willingly bypassed worker safety regulations, resulting in the death of an employee in a confined-space trench accident.

Deep shaft rescues are high-risk operations for all involved. Consequently, the officer in command must seriously consider the potential consequences of committing personnel to enter a confined space. A major factor here is the viability of the victim. If conditions are such that it is impossible for any victim to survive, the question becomes, should rescuers` lives be risked to recover bodies and perform any other nonlife-saving tasks in a deep shaft? The decision becomes even more difficult (and more important) when the victim`s exact condition and conditions within the shaft are unknown. Rescuers have died under such conditions, partly because of the urgency that accompanies situations in which a victim is known to be “trapped” in a shaft and it is not possible to determine from the surface the exact conditions within the shaft. The IC and technical specialists` experience, training, and good judgment are most important at such a time.

The latter part of this article outlines safety considerations and procedures applicable in deep shaft rescues. The two incidents cited below illustrate how critical these factors are for successful operations.

SANTA MONICA MOUNTAINS DEEP SHAFT RESCUE

On May 26, 1995, a female probation work crew was performing weed-abatement work in the rugged Santa Monica Mountains above Malibu. One of the women walked over a rotting piece of plywood covered by a thick layer of dirt and weeds that had hidden beneath it a vertical shaft, 65 feet deep and 30 inches in diameter. The plywood cover collapsed beneath the woman`s weight, and she fell straight to the bottom of the shaft, where she became trapped. She lay there with broken bones and serious internal injuries.

The shaft had been bored into the ground decades earlier, perhaps as part of an abandoned geologic survey. It is one of hundreds of open shafts present throughout Los Angeles County, the results of construction projects, geological tests, water wells, abandoned septic systems, and tunneling projects.

The Response

Minutes after the woman fell, the County of Los Angeles Fire Department (LACoFD) Command and Control Facility received a 911 call. A first-alarm confined-space rescue assignment was dispatched. The assignment included two engines, one brush patrol, one Urban Search and Rescue (USAR) aerial ladder company, one paramedic squad, one hazardous materials task force, one mobile air utility, one air squad (a fire/rescue helicopter), USAR-1 (the department`s central Urban Search and Rescue Company), and one battalion chief.

Air Squad 8 and USAR-1 responded from the LACoFD Special Operations Division facility in Pacoima, about 40 minutes driving time from Malibu. To expedite the response, USAR-1 Captain Donald Roy and Engineer Richard Meline loaded a Larkin rescue frame (described on page 96), confined-space equipment, and rope-rescue gear onto Air Squad 8 and flew in the helicopter. Meanwhile Engineer Ysidro Miranda responded with the USAR-1 apparatus to provide special equipment for the incident, including the unit`s air knife, air vacuum, a large-capacity air compressor, and other items. As Air Squad 8 lifted off, the crew heard the radio size-up report from Engine 71. A woman was confirmed to be trapped at the bottom of a 50-foot-deep shaft with a diameter of 30 inches.

The Operation

Engine 71`s captain, Donald Hull, a USAR instructor and a technical team manager assigned to the LACoFD`s FEMA US&R Task Force, immediately recognized the confined-space nature of the incident, as well as other hazards particular to deep shaft rescues. He established command and directed his crew to begin stabilizing the rescue site by placing plywood around the shaft`s perimeter to prevent point loading of the edges. Concerned that more open shafts might be hidden beneath the brush and dirt on the site, he instructed personnel to check for additional holes. None were found.

He then assigned one of the Squad 71 paramedics to don a rescue harness, tether himself to a secured rope to prevent falling into the shaft, and crawl (on the newly laid plywood deck) to the edge of the hole to maintain constant visual and verbal contact with the victim and to assess her condition. The paramedic remained at the edge of the shaft throughout the incident, watching for telltale signs of deterioration of the victim`s mental state or indications that her physical condition was deteriorating.

The patient was quite agitated at first, leading the paramedic to suspect that she might be suffering from hypoxia resulting from a decreased level of oxygen at the bottom of the shaft. This could not be confirmed until Haz Mat 76 or USAR-1 arrived with atmospheric monitoring equipment.

In the meantime, Hull assigned Engine 88 to begin ventilating the shaft with a fresh air blower and prepare an air line to force compressed air from SCBA bottles into the bottom of the shaft.

The captain of USAR Truck 125 was designated safety officer and rescue group leader until USAR-1`s captain arrived. Truck 125`s crew was assigned to begin setting up dual high-angle rope systems in preparation for lowering a rescuer into the shaft and pulling the rescuer and victim out.

For USAR-1`s Captain Roy, who was aboard Air Squad 8 en route to the incident, this would be the second deep shaft rescue in Malibu within a year. Just nine months earlier, he and Battalion Chief Keno De Varney had supervised the rescue of an 11-year-old boy who had fallen down a 50-foot shaft just six miles from this incident site.

After Air Squad 8 landed, Roy reported to the command post for a face-to-face briefing with Hull and others. Haz Mat 76 Captain Matt Gil explained that his crew had just finished monitoring the shaft and that the oxygen concentration was a low 16 percent [levels less than 19.5 percent require the use of self-contained breathing apparatus (SCBA) or supplied air breathing apparatus (SABA)]. The rescue plan included using standard confined-space rescue techniques, umbilical air systems for the rescuer and victim, dual rope systems, and a Larkin frame from which to lower Meline, the rescuer, into the shaft.

Meline was lowered into the mouth of the shaft to remove the rotted plywood debris that became jammed in the upper third of the shaft when the victim fell through the cover. Some of the plywood, which obstructed nearly two-thirds of the shaft`s diameter, still had a two-inch layer of dirt caked to it; additional soil was piled on top of the pieces. It not only made the plywood heavier and more likely to fall, but it created an inhalation and burial hazard for the victim. Meline scooped the dirt into buckets attached to ropes and tended by personnel on the surface. When the buckets were filled, they were raised and emptied. After the dirt was removed, Meline carefully pulled apart the pieces of plywood and sent them to the surface.

Haz Mat 76 took another atmospheric reading in the shaft and reported that the oxygen content had risen to 20 percent. A harness was lowered to the victim with a rescue rope. She was instructed to don the harness for a lifting operation. The decision to allow the victim to don the harness herself was part of the risk-vs.-gain evaluation made at this incident and required at all technical rescues. In this case, it had been determined that the victim was able to follow commands, even though she was in considerable pain. The reasoning was that it would be safer for all involved to lower Meline just deep enough into the shaft to allow him to supervise and evaluate the victim`s donning of the rescue harness, which was already attached to a dual rope system suspended from the Larkin rescue frame. If she were unable to don the harness properly, Meline would have been lowered to the shaft`s bottom to perform the task.

The woman was raised from the shaft in a little more than an hour and 15 minutes. Various factors contributed to the timely and safe conclusion of this incident. They include the experience acquired by on-scene personnel during previous deep shaft and confined-space operations, their training, their research into shaft rescue incidents that have occurred elsewhere in the country, as well as their adherence to standard principles applicable to deep shaft/confined-space rescue operations.

RESCUE IN ABANDONED GOLD MINE

On Saturday, April 4, 1998, the LACoFD received a report of a man trapped in an abandoned gold mine known as the “Black Jack.” The ensuing rescue from a 900-foot-deep vertical shaft within the mine lasted more than seven hours and required the efforts of 65 LACoFD members and a Sheriff Department mine rescue team.

Black Jack Mine is located near the rural community of Acton, in the mountains that separate Los Angeles from the Mojave Desert. It is one-half of a mile from the infamous Governor Mine, which still entombs the body of a man who succumbed in 1981 to its poisonous atmosphere while exploring the deep mining shafts that honeycomb these rugged hills. Conditions inside the Governor Mine were deemed so hazardous that the recovery operation was halted to protect rescuers` lives; some rescuers barely escaped with their own lives. The Governor Mine was sealed with the corpse left in place. Both the Governor and Black Jack mines are just a few miles from the San Andreas Fault line, to give an indication of the geological makeup of the region.

At 15:33, LACoFD Command and Control dispatched a “person trapped” response, which was later upgraded to a confined-space rescue response. By the time the incident was over, the following units were committed to the incident: Battalion 17; USAR-1 and USAR-2; Truck 24; Air Squad 8; Engines 81, 131, 24, 107, and 1; Patrols 80, 92, and 79; Haz Mat Task Forces 76 and 43; Squad 37; Mobile Air Unit 107; Utilities 4 and 6; Biopack 82; Safety 7; Communications 1; Info. 5; the Battalion 17 USAR Trailer, and the Antelope Valley and Montrose Search and Rescue teams of the Los Angles County Sheriff Department (Montrose SAR is a certified mine rescue team in California).

The Operation

On their arrival, E-80 and Battalion 17 Chief David Moore reported a working rescue deep inside the mine, located one-half mile up a four-wheel-drive road from an access road. Chief Moore established Crown Incident Command and then assigned Engine 80`s captain as Operations. Truck 24, with Captain Al Shriver and Engineer Jeff Hudspeth (both certified in confined-space rescue), arrived soon thereafter. Shriver was assigned as confined-space/tunnel safety officer and Hudspeth as the confined-space rescue entry attendant. As Chief Moore gathered information from the victim`s son, an exclusion zone at the entrance to the mine was established, as were a support zone and an equipment pool. Captain Matt Gil of Haz Mat 76 was assigned as entry team manager.

The victim`s son recounted that they were exploring at approximately the 400-foot-depth of the vertical shaft and had decided to return to the surface; the son was leading. The rope on which the father was hanging suddenly parted, and he fell 50 feet onto a ledge. It was fortunate that he did not fall an additional 400 feet (or more) to the bottom of the shaft.

The son attempted to help his father climb from the mine on another rope, but he reached the limit of his physical abilities at a ledge that was 100 feet below a lateral access shaft. Here, he was forced to leave his father behind to call for help. He reported to Moore that his father had been conscious and talking when he last saw him.

USAR-1 arrived at the scene 15 minutes later. As the on-duty captain of USAR-1, I was assigned as rescue group leader and instructed to evaluate the rescue situation while the USAR-1 engineer began removing essential equipment for the mine entry teams. Engineer Pat Rohaley from Engine 131 was assigned to accompany me into the mine as Entry Team 1 (we both are confined-space rescue-certified), to monitor the atmosphere in the tunnel, make contact with the victim, assess his condition, and rapidly assess the actual rescue problem before exiting to suggest the rescue plan. We were equipped with SCBA, air, haz-mat/air monitors, three sources of light, rescue ropes, tag lines, and other gear.

Two firefighters from Haz Mat Task Force 76 (Phil Enriquez and Cory Lovers were assigned as the rapid intervention team (RIT) outside the mine and identified as Team 2. A high-volume confined-space ventilation fan was placed in service at the tunnel entrance. As Team 1 prepared to enter the mine, members of the Antelope Valley and Montrose SAR teams arrived and checked in with Crown Incident Command. Unified command was established, and members of the Montrose Team were assigned to augment the RIT.

Entry Team 1 went into the lateral entrance of the mine, which extended 80 feet into the mountain through hard rock and then turned right for 60 feet. There they came to the vertical shaft in which the victim was trapped. The atmospheric readings at the vertical shaft were oxygen, 20.5 percent; carbon monoxide, 0; and hydrogen sulfide, 0 ppm. The explosive LEL was negative. Thus assured that there was no explosive hazard, Team 1 set up two floodlights powered by a generator located a safe distance from the mine`s entrance.

Team 1 made voice contact with the victim and determined that he was conscious and oriented, in stable condition, and trapped on a ledge approximately 100 feet below, at the intersection of a lateral tunnel. Because of the angle of the vertical shaft, the entry team could not see the victim. The patient was cold and thirsty; clothing and a canteen of water were lowered to him with a tag line. Team 1 then evaluated possible rescue options. They then assured the victim that they would return shortly and exited the mine, leaving the floodlights and one air monitor in place.

The Rescue Plan

The following plan was adopted:

Keep Team 2 in place as the RIT.

Reconfigure Team 1 by adding two members from the Montrose SAR Team (Bruce Parker and Rick Homan) and two additional LACoFD confined-space team members (Meline and Enrique) to augment USAR-1`s captain and Rohaley, the original Team 1. The new team was designated Team 3 to eliminate any chance that there would be confusion concerning who had actually entered the mine.

Team 3 would enter the mine with USAR-1`s Larkin frame, picket anchors, rope systems, and other equipment. SCBA for each member and the victim would be cached in the working area of the mine in case of a change in the air quality within the tunnels. The mine would be continuously monitored.

Team 3 would rig the rescue systems, maintain contact with the victim, and continue to monitor atmospheric conditions. A rescuer would be lowered to conduct a “pick-off” rescue.

When Team 3 was ready to haul the victim and rescuer from the shaft, four additional confined space and mine rescue-trained personnel would be called in as a rope-hauling team.

The victim would be treated, packaged, and removed from the mine, followed by the rescuers.

The LACoFD`s SABA would be positioned outside the mine in case it were needed for umbilical air supply. The LACoFD`s biopack rebreather SCBAs were already en route from the Special Operations Division to provide long-term “rebreather” SCBA if needed.

Team 3 would bring USAR-1`s remote search camera “probe” (on a 240-foot reel of hard wire) so the operations could be monitored by personnel outside the mine as an added safety measure. The probe would also allow for two-way hard-wire communication.

With rain falling outside, Team 3 entered the mine carrying the search camera probe. Team 3`s leader reestablished voice contact with the victim and explained the plan. Meanwhile, the others assembled the Larkin frame, established a picket anchor system in the tunnel floor, established a two-rope raising and lowering system, and continued to monitor the atmosphere. They took measurements that were relayed to the shoring team outside the tunnel, which constructed two “dead man” anchors from 4 2 4 timber. The anchors were wedged into crevasses across the width of the tunnel.

T-24 built another picket anchor system outside the mine. This system was connected by a mechanical advantage rope system to the picket system in the tunnel, to “back up” the interior anchor system for maximum personnel safety.

The search camera remote probe was lowered into the shaft to attempt to get a view of the victim and any unseen hazards. Several areas of concern were identified. Of primary concern were old timbers that bisected the shaft horizontally every 30 to 40 feet; they could complicate the vertical movement of the rescuer and victim.

Using the Larkin frame, which allows the rescuer to be suspended over the center of a shaft, Team 3 began lowering the rescuer. He had to “step over” the horizontal timbers he encountered in the shaft. When he reached the victim, he treated him for cuts, abrasions, and other injuries. Then he placed a “half-back” vertical lifting C-spine harness and another rescue harness on him. At this point, the rope-hauling team in the mine was augmented by personnel from HMTF 76. With their assistance and the use of a 3:1 hauling system, the victim was raised out of the vertical shaft and placed in a rescue litter. He was quickly removed from the mine, evaluated by Squad 37, and transported to a hospital, where it was discovered that he had a fractured orbit and other serious facial injuries that would ultimately require surgery.

The rope haul team was switched out for personnel from HMTF 43, and Team 3 lowered the main line and safety line back into the shaft to remove the rescuer, who was waiting on the same shelf where the victim was found. The ropes passed “under” the horizontal timbers, meaning the rescuer would also have to go “under” them as he ascended. A safety problem was encountered when the main haul line contacted one of the horizontal timbers, moved it out of position, and left it dangling 50 feet above the rescuer. If it had come loose, it most likely would have struck the rescuer on its way to the bottom of the shaft.

Entry Team 3`s leader called “all stop” so the situation could be assessed. Any further movement of the main line while under tension from the rescuer`s weight might cause the loose timber to fall on him, possibly incapacitating him. There appeared to be only two options: (1) rig a separate raising/lowering system, and lower another rescuer into the shaft to secure the timber and remove it; or (2) have the rescuer ascend the safety line using rope ascenders and use the original main line as a safety line to prevent the main line from affecting the timber.

Option 2 was chosen. Moving very carefully, the rescuer switched over to rope ascenders on the safety line. Team 3 adjusted its tactics to allow him to ascend the rope while providing a safety belay with the original main line (a very delicate operation). Any wrong move might cause the timber to fall on the suspended rescuer and severely complicate the situation. Fortunately, the rescuer was able to ascend without further incident and exited the shaft safely.

At the safety officer`s recommendation, Team 3 exited for rehab. After rehab, the team members reentered and broke down the rescue system. With assistance from other personnel, all equipment was removed to the proper apparatus.

At the conclusion of the rescue operation, Public Works and the Sheriff Department were requested to secure the mine entrance. The victim is still recovering from his injuries.

SAFETY PROCEDURES FOR DEEP SHAFT OPERATIONS

Safety can be especially precarious in a deep shaft rescue operation. Among the precautions, considerations, and procedures vital to success are the following. All are equally important and are not presented in any specific ranking order.

Clothing. Always wear approved fire resistant safety clothing in a space with the potential for toxic or flammable hazards. Turnouts may be too cumbersome and restrictive for the entrants. Consider a NomexT jumpsuit or brush pants, a jacket, and a hood. Don`t forget the obvious safety gear such as helmets, gloves, goggles, boots, and so on.

Respiratory protection. Rescuers in the shaft and near the opening should always wear SCBA or SABA when the atmosphere is or potentially may be IDLH (immediately dangerous to life and health). Rescuers should not enter the shaft if they have to remove their SCBA to fit into the shaft entrance. The entrant must have a facepiece in place with the hose connected before entering the confined space. Lowering the SCBA bottle/ backpack after the rescuer is not acceptable. The bottle/backpack might be dropped and rip the mask off the rescuer`s face, exposing him to the IDLH atmosphere. A rescuer should never remove an air bottle from his back for any reason. If the rescuer cannot get in with the SCBA on his back, he should not enter the shaft or should use SABA, such as an umbilical air system that has a backup air supply for emergency exit.

Although SABA is the most effective respiratory protection for confined-space and deep shaft rescues; it may be cumbersome for rescuers operating in the narrow confines of a shaft. Consider all the objects that must be passed into the entrance of a shaft to support a rescue operation: ropes, hardware, tag lines, air lines, air blower tubes, atmospheric monitors, hardwire communications lines, lighting, patient extraction litters and harnesses, and so on. These items will not only clog the entrance to the shaft and limit emergency egress, but they will reduce the amount of available light and present additional entanglement hazards for the rescuer and victim.

The rescuer should take into the space an extra SCBA or SABA mask for the victim. The entry team should have its own air source. The backup entry team should have its own air source.

Preferably, there should be only one entry team per SABA system. However, a victim air source may also be supplied by the entry team`s SABA system. Thus, a maximum of three air sources (two entrants, one victim) should be run from one SABA system. Three complete sets of SABA are recommended to provide the primary and backup teams with their own air supply with one set to support a failure. If air supply is lost, the emergency escape bottle is used. If air supply is reestablished during exit, rescuers continue to exit.

Psychological implications. Deep shaft rescues evoke a particularly high level of fear. Many people are reluctant to be lowered into the earth for any reason, particularly when required to pass through a narrow opening or some other physical constriction. The diameter of the work area physically restricts movement (and may prevent immediate escape). When exposed to deep shaft or confined-space rescue conditions, some firefighters may discover for the first time that they are claustrophobic. For rescuers already hindered by claustrophobia or other exaggerated fears, exposure to adverse conditions such as those that might be experienced in deep shaft rescue operations may lead to panic and other potentially damaging behaviors.

Additionally, many things can go wrong under the ground, among them complications with umbilical air lines, SCBA systems, and rope systems and the collapse of shaft walls. There is little room for error in a narrow vertical shaft and even less chance for recovery if an accident affecting the rescuers should occur. Backup rescue methods commonly employed during “normal” confined-space rescues are sometimes unfeasible because there may not be sufficient room for backup rescuers to enter the space to assist the original rescuer(s). There may be room for only one person at a time in the shaft. Also, if a major collapse were to occur and if water or a hazardous material were to be introduced, there may be no way to reach the primary rescuer in time to prevent life loss.

Atmospheric monitoring. Consider all confined spaces IDLH until proven otherwise. Test the shaft`s atmosphere prior to entry and before working near the entrance of any confined space. Use test results as a baseline for further testing. Test from the point of entry and preferably every four feet vertically until reaching the bottom of the shaft. Testing instruments may have to be lowered and raised with rope. Follow the manufacturer`s instructions for obtaining samples. Continue monitoring throughout the incident. Atmospheric monitoring is usually done with a direct reading instrument. Monitoring by a three- or four-range monitor should minimally include testing for oxygen percentage, percentage of combustibles (percent of LEL), and toxicity. Monitor before ventilating. Maintain a written record of test results until the incident is over.

Oxygen deficiency is a major hazard. A 1985 OSHA study revealed that of 173 confined-space fatalities, 67 were in nontested, oxygen-deficient atmospheres. Even a small reduction of the oxygen percentage indicates that some process is actively reducing the level of oxygen in the shaft.

Whenever a victim has reportedly become incapacitated or is missing in a deep shaft, suspect IDLH atmospheres until direct monitoring with appropriate instruments proves otherwise. In atmospheres with levels of oxygen below 19.5 percent, SCBA or SABA is required by law for workers and rescuers in the United States.

Whenever a person crosses the plane of the entrance of the confined space, he is considered to have entered the space, or the exclusion zone. To avoid accidental exposure to IDLH products, avoid placing any body part in or near the opening of the space to assess the situation or communicate without proper protection.

Combustible atmospheres may ignite or explode if a source of ignition is present or introduced. Combustible agents may include naturally occurring gases, vapors from liquids such as fuels or solvents, or dusts of combustible materials. Flammable vapors and gases are considered hazardous when they reach 10 percent of their lower explosive limits (LEL).

Some flammable gases may flow into deep shafts naturally or be introduced into the shaft accidentally. An oxygen-enriched atmosphere (23.5 percent +) increases the potential for ignition. Different gases, heavier or lighter than air, will seek lower or higher levels (stratification) in a deep shaft. Desorption of chemicals from the walls of the confined space may create a flammable atmosphere. Dusts may become explosive in certain concentrations. Generally, dusts are considered explosive when particulates reduce visibility to less than five feet, but some materials may reach dangerous concentrations long before this happens.

The atmosphere of a deep shaft might contain asphyxiants and irritants that can cause disease, illness, injury, or death. Effects can be immediate or delayed. As an example, carbon monoxide (CO), formed by incomplete combustion of fuels containing carbon and in the decomposition of organic matter, may be found in some deep shafts. CO is odorless and colorless and may quickly reach lethal levels in a confined space, giving little to no warning before a victim or rescuer is overcome. Also, hydrogen sulfide gas is produced from the natural decomposition of sulfur-containing organic matter and, in extremely high concentrations, by raw sewage. Exposure to low concentrations may cause pulmonary complications. Exposure to higher concentrations may cause unconsciousness and death in seconds. The rotten egg odor may not seem present at higher concentrations because exposure paralyzes the olfactory nerve, which controls the sense of smell.

Ventilation. Ventilation of a deep shaft requires consideration of the following factors:

* Is the victim unconscious? Is the unconsciousness due to a physical injury or the atmosphere in the confined space?

* Is the proper equipment on-scene to safely perform the operation?

* Ventilation, once started, should continue throughout the operation unless it creates additional hazards.

* When ventilating, consider where the exhaust is going. Is it IDLH, and will its removal create a hazardous atmosphere somewhere else?

* Ventilate where it will do the most good for the operation.

* Will the introduction of air into a space that contains a flammable gas bring it to within its explosive limits, thereby increasing the hazard of ignition?

* Entry into a shaft must be considered only after complete ventilation and continued monitoring of the atmosphere have demonstrated that it is safe.

* Should you blow in fresh air or suck out toxic fumes, or both? Consider additional openings that may help with ventilation and will not counteract positive-pressure ventilation.

* Take care to prevent recirculation of contaminated air or circulation of exhaust gases from generators or vehicle exhaust into the shaft.

* Consider the use of built-in ventilation systems and positive-pressure ventilation.

* Ventilate at all levels due to stratification of gases. Air streams need to create continuous turbulence throughout the space to achieve proper ventilation/air exchange.

* Water fog nozzles do not produce small enough water droplets to inert a deep shaft atmosphere. The droplets may also increase flammability due to increased air flow into the space (and may even drown the victim if not used carefully).

* Withdrawing air via an intake duct from the bottom of the space is the most effective method of removing heavier-than-air gases.

* The ventilation fan(s) and ducting should be rated for hazardous atmospheres whenever there is a potential for flammable gases.

* Remember, the only way to assess ventilation effectiveness is to continuously monitor the atmosphere!

Lock out, tag out. Lock-out, tag-out, blank-out procedures are required to prevent severe life hazard from accidental reactivations of machinery or the introduction of toxic substances. All electrical, mechanical, and other forms of energy must be shut down and deenergized prior to entry. All valves, switches, gates, or other control devices must be locked out with a keyed padlock and tag that says “DO NOT REMOVE. DO NOT TOUCH.” Hydraulic lines and pipelines must be blanked or blinded by disconnecting or using a provided steel plate blank-out system. The system shall then be bled to ensure deactivation. The key should stay with the individual who places the lock or be given to a responsible person, such as the safety officer, attendant, or IC. If the device cannot be secured and locked out, you must tag the switch and station an entry team member at the device or switch to prevent activation. Locate a responsible party intimately familiar with the systems to assist.

Harness. All rescuers (including backup rescuers) should wear an approved rescue harness when working near the shaft opening. At the least, the harness should be NFPA-compliant for high-angle rescue operations and capable of suspending and maintaining a rescuer in an upright position. A better choice is a harness certified for use in confined-space rescue operations. When making a vertical entry into a confined space, OSHA requires the entrant to be in a vertical lift harness attached to an approved haul system.

Most confined-space harnesses include features that allow the wearer to invert himself and safely work upside down when necessary. Although inverting carries with it certain health risks for the rescuer (increased blood pressure in the head, for example), some rescuers may have to work while in an inverted position for brief periods. This is a call based on prevailing conditions and the judgment of the individual rescuer and his supervisors (as well as a trained safety officer). Use an approved hoisting device or rope rescue system (with a belay or safety line) for lowering and lifting rescuers in the shaft.

Attach a tag line to the lead entrant if the shaft leads to a horizontal tunnel. This will guide a rescue team to the primary entrant, will guide the primary rescuer back out to the shaft, and can lead the relief teams to the victim.

RIT. Just as in other IDLH situations, at least one RIT is required to remain at the ready outside of the shaft to provide immediate assistance in case of an emergency. In confined-space and deep shaft rescues, there must be at least one RIT member for each primary entry team member. RITs are required by law to wear appropriate protective equipment and must have a separate breathing air source available and ready for immediate use. Essentially, RIT team members should wear the same equipment as the primary rescue team.

Lighting. Use only listed/approved (intrinsically safe) lighting and electronic equipment rated for hazardous atmospheres. Listed/approved lighting will have a UL, FM, or MSA (Mine Safety Administration) rating. Each entrant should have with him a minimum of three light sources.

Tools. Use nonsparking tools (aluminum or coated) in a combustible atmosphere.

Communications. Effective communication between personnel inside the shaft and backup rescuers must be maintained throughout entry. If hazardous materials are involved, standard hazardous materials procedures should also be enforced.

OSHA mandates effective and uninterrupted communications with the entry team during confined-space entries. Communications must be established prior to entry and maintained throughout the operation, be functional when breathing apparatus is in use, and be intrinsically safe.

Point-of-entry control. Point-of-entry control is an absolute must in confined-space entry. The following tasks must be done, and the assigned safety officer must oversee them:

* Keep a written record of the names, functions, and times of entry of each entry team member.

* Monitor the maximum entry time for each entrant. Strictly enforce the established maximum time, which may vary according to the entrant`s air bottle reading and the effort expended.

* Maintain written records of atmospheric tests throughout the incident. Record monitoring by each entry team and at the point of entry.

* Have ready at the entrance to the shaft at all times a backup rescue team equivalent to the entry team in number and protective clothing and equipment. Record their names.

* Maintain visual monitoring of entrants at all times.

Vertical entry considerations. If the operation requires rescuers to be lowered into a shaft, a trained high-angle rescue team supervised by a qualified officer should be assembled and assigned to establish and operate a high-angle system. An officer or other member trained in Rescue Systems I, Rigging for Rescue, or another recognized high-angle rescue course should thoroughly review the conditions and requirements. This individual may be assigned as extrication officer. The extrication officer should be responsible for developing and operating a safe and effective high-angle entry/egress system, with appropriate safety redundancy (i.e., dual rope systems, and so on) and backup rescue capability.

Fall prevention. All personnel operating near the opening to a deep shaft should be properly harnnessed and tied off (belayed) to prevent their accidentally falling into the hole. Plywood or other decking material should be placed around the edges of the shaft to prevent collapse from point loading or the accidental kicking of objects and debris into the shaft.

Engulfment and collapse hazards. These hazards exist in some deep shaft situations, as they do in some aboveground confined spaces such as grain silos, borax silos, and the like. In some cases, a “crust” bridge may develop as material quantity decreases in the shaft or space, creating a thin surface above a hidden void that looks deceptively solid but will not support the weight of rescuers.

On-site cranes or hoists. One question that naturally arises at many deep shaft incidents is, should on-site cranes or hoists be used to lower and raise rescuers and victims? Experience has shown that cranes and other heavy-duty lifting machines may be found at rescue scenes at construction sites and subterranean projects. A qualified individual should carefully evaluate these capabilities before the decision is made to use them to raise and lower personnel and victims. Some machines, because of their immense power and lack of adequately precise controls, may be unsafe for live loads or may be unrated for lifting and lowering people. The danger of using mechanical raising/lowering devices increases when working in the confines of a shaft, which may be very unforgiving if the device is not used with exacting precision.

Do not automatically eliminate consideration of the use of on-site cranes and hoists if they are not rated for live loads. In some cases, they may be the most appropriate way to conduct a timely rescue. The LACoFD and other agencies have used on-site cranes and hoists to successfully manage many subterranean rescue operations, including those in deep vertical shafts. However, using a machine to perform a task for which it is not designed always carries a certain amount of risk. Failure to use due caution may subject rescuers and victims to severe injuries (or worse), worsening the situation and defeating the purpose of the emergency response.

Many shaft rescues can be best handled by establishing standard dual lowering/raising systems with a high-anchor point established over the center of the hole. The Larkin frame, an aluminum device invented by Australian firefighters for cliff rescues, provides an excellent anchor point that can be pivoted directly over the center of the shaft to lower and raise rescuers. Once the rescuers and victim(s) are brought to the surface, the Larkin frame is maneuvered to swing them back over solid ground.

For narrow-diameter shafts, a standard A-frame may provide a workable anchor point sufficiently high over the hole to allow easy entry/egress by rescuers and a patient litter. Naturally, it is safer to rig the A-frame with dual rope systems before it is centered over the mouth of the shaft. This will help prevent a fall into the hole during rigging operations. The A-frame should be adequately secured to prevent it from “walking” as a result of the influences of the rope systems and other factors.

Another method of establishing a high-anchor point is to use a crane or an aerial ladder as an anchor platform. In this case, the crane`s power system or winch is not used to raise or lower victims and rescuers. Instead, the crane or ladder is positioned over the shaft and secured in place using appropriate means (this, of course, assumes that the operator has already calculated the potential forces and has determined that the loads are within the rated capacities of the crane or aerial ladder).

Organizational structure. The organizational structure for deep shaft rescue incidents should be consistent with standard incident command system (ICS) principles and take into consideration the probable need for some level of unified command. Participating agencies may include law enforcement, utility companies, mine/rescue teams, and mine and tunnel safety authorities.

Establish the command post outside but within the line of sight of the immediate operations area. Stage all personnel not immediately assigned to specific duties outside the operations area in an easily accessible location. The first-arriving unit should determine the appropriate command post and staging locations and have the dispatcher relay the locations to all responding fire department companies and other assisting agencies.

Assign a confined space rescue-trained safety officer and rescue group leader. Assign a medical group leader to establish treatment for the victim and, if necessary, rescuers who may become trapped or exposed to IDLH substances. If necessary, establish a search group leader.

Establish an exclusion zone (the danger zone into which no personnel should enter without suitable safety equipment). Establish an operational zone (a 100-foot perimeter around the exclusion zone), in which primary and backup rescue team and support operations will be conducted. Outside the operational zone, establish an equipment pool, logistics, rehab, and entry control. Outside the perimeter of the incident, establish a zone for media, bystanders, and public officials, who will often appear at extended deep shaft operations. Use fire line tape or other barriers to delineate the different zones. Assign a public information officer to deal with the media, and request law enforcement to control crowds and traffic.

Standard operational positions. The following positions, with their attendant duties and responsibilities, are required for successfully managing many deep shaft rescues:

* Rescue group leader or operations officer–supervises the overall rescue operations:

–Develops, with the IC, the rescue plan, which is part of the incident action plan.

–Supervises overall rescue operations.

–Interacts with the safety officer and others to ensure maximum safety.

* Entry team manager–supervises the attendant, rigging team, and litter team and other critical operations at the point of entry.

–Must understand the hazards that may be encountered.

–Develops, executes, and updates the entry plan.

–Maintains overall accountability for safe entry operations to include Lookout, Communicate, Escape Routes, and Safety Zones (LCES).

–Ensures that a written log is maintained.

–Ensures removal of unauthorized persons who enter or attempt to enter the space or work area.

–Ensures and verifies that all tests and procedures are performed and that required equipment is used.

* Safety officer–responsible for ensuring adequate safety procedures, alerting the IC to any unsafe situations, and halting any unsafe operations.

* Air supply officer–responsible for ensuring that a continuous supply of air is maintained to all rescue entrants and the victim (when umbilical air is supplied to the victim) throughout the incident:

–Must have a working knowledge of all equipment and procedures related to a breathing air supply.

–Operates supplied air breathing apparatus (umbilical air system), plans and performs air-bottle exchanges as necessary, and ensures backup air supply.

–Supervises all other tasks related to air supply.

* Primary entry and rapid intervention (RIT)–generally, two-person entry teams are desirable for confined-space rescues. If the shaft will allow that entry be made by only one person at a time, then, naturally, the teams will each consist of one person. The duties of both teams include the following:

–Know the hazards that may be encountered.

–Properly use the equipment provided, including testing and monitoring, communications, SCBA, SABA, and so on.

–Communicate with the attendant as needed.

–Alert the attendant when a dangerous situation or prohibited condition is recognized.

–Exit the space when a hazard or prohibited condition arises, or when the attendant or entry supervisor orders an evacuation.

–Locate and extricate victims from the space.

–Conduct rope rescue operations to remove victims.

–Backup entry teams must be prepared to rescue the primary teams.

* Attendant–monitors the condition and progress of the rescuers in the shaft from the point of entry.

* Rigging team–generally led by the captain of the USAR or rescue company or another person qualified to supervise high-angle rope systems and other systems for inserting and removing rescue teams and the victim from the shaft and extracting trapped victims.

* Line tenders–tend the safety rope of entry teams as they make their way through the confined space; there should be a minimum of one tender per entrant.

* Litter team–four personnel to transport the victim from the point of entry to the medical group.

* Ventilation team–works under the supervision of the air supply manager to ensure continuous and effective fresh air exchange in the confined space.

* Air source manager–works under the supervision of the air supply officer to ensure a constant supply of breathing air from mobile air units, SCBA caches, and so on.

Some may scoff at the commitment of a large number of personnel. For some departments, this response is the equivalent of a second-alarm fire. Be that as it may, years of experience in managing actual deep shaft incidents have shown that this commitment is prudent to ensure reasonable safety for personnel and victim(s).

Victim handling, packaging, and extraction. The type of injury or illness will determine whether BLS or ALS procedures are required. Because rescuers may become entrapped and have to remain in deep shafts and other confined spaces, only minimal first aid–the ABCs, immobilization, and control of major bleeding–is administered until the victim is removed to a safe environment. The priority treatment is removal from the hazardous environment.

Several extrication and immobilization aids are available. Again, the situation, the type of space, the size of the opening, whether there is to be a vertical or horizontal entry, and the victim`s condition will help determine the equipment and methods to be used. For many shaft incidents, an LSP Miller half back, rated for vertical lifting operations, is an excellent extraction harness. A KED is also an excellent choice, if the space allows. Consider commercially made wrist harnesses, which are designed to lift trapped victims by the wrists when other parts of the body are not accessible. The LACoFD has used this method several times to rescue victims trapped between buildings, in trench collapses, and in crevasses.

During extrication, do not block the rescuer`s egress with equipment or the victim. Consider raising the rescuer(s) on the rope system with the victim suspended on the system below in a position that allows both to be raised without creating a blockage.

Ensure that a medical team is awaiting the removal of the patient(s) so that medical care may be initiated/continued.

Decontamination. Be prepared to decontaminate rescuers and victim(s) should it become necessary. Victims should be decontaminated before being loaded into an ambulance or a helicopter for transportation to a hospital. IDLH fumes emitting from a contaminated patient can quickly cause a secondary disaster if the driver of an ambulance or the pilot of a helicopter were to be overcome or if a contaminated patient were to contaminate personnel and patients in the hospital emergency room. n

(Top left) A firefighter is lowered into a narrow shaft during a training exercise. He is breathing fresh air from an umbilical system as a dual-rope system is being used to lower and raise him and a high-volume fan is blowing fresh air into the shaft through collapsible ventilation tubing. (Photos by author unless otherwise noted.) (Top middle) A firefighter is lowered into a deep shaft rescue training prop in Los Angeles County. (Top right) To accomplish the rescue from a 70-foot-deep shaft, two standard fire service ladders were lashed together to form an A-frame, which was then placed over the shaft to provide a high “point of departure” that will allow the rescuer to be lowered into the center of the hole. Guylines were anchored on both sides to provide lateral stability. A dual-rope raising and lowering system was suspended from the A-frame. These are standard techniques taught in Rescue System I, adapted for use in deep shaft confined-space rescue situations. (Photo by Gary Thornhill.) (Bottom left) An aerial ladder may be used to provide a high “point of departure” for the rescuer to be lowered into the center of the shaft. Never load the aerial ladder beyond its rated capacity, and never side-load (“tweaking” the ladder may cause severe damage). This approach should be considered only if the ground has been determined to be sufficiently stable to support the load of the aerial apparatus without compromising the integrity of the shaft walls. Here, it is acceptable because the shaft is lined with steel. Use extreme caution if the shaft has been bored through unsupported earth. (Bottom right) Inside look at a deep shaft rescue prop at the new LACoFD Del Valle Training Center. The ladder is provided for emergency escape or assistance from above if it becomes necessary during the course of training. Emergency escape panels are at the bottom of the shaft prop.

(Top left) While exploring, the victim became trapped on the ledge in this 900-foot-deep vertical shaft in an abandoned gold mine in the Los Angeles suburb of Acton. The seven-hour rescue operation involved the Los Angeles County Fire and Sheriff departments. (Photos by Richard Meline.) (Right) After crawling deep into the abandoned gold mine and monitoring for a toxic atmosphere, personnel from LACoFD USAR-1 and the Montrose SAR Team were able to doff their SCBA, which was kept at hand in case the monitoring instruments indicated a deterioration in conditions. They assembled a Larkin rescue frame, established flood lighting, and built a dual-rope rescue system that was anchored to an interior Spanish windlass “backed up” by “deadman” anchors and yet another picket anchor system outside the mine. (Bottom left) The victim is removed from the mine shaft.

LARRY COLLINS is an 18-year member of the County of Los Angeles (CA) Fire Department; a paramedic; and one of three captains assigned to USAR-1, the LACoFD`s Urban Search and Rescue Unit, with responsibility for supervising deep shaft rescues, confined-space rescues, and other technical rescue operations across Los Angeles County. Collins served as a member of FEMA`s USAR Incident Support Team at the Oklahoma City Bombing and assistant leader of the LACoFD FEMA USAR Task Force (CATF-2) at the Northridge Meadows Apartment Collapse. He is a member of the LACoFD Anti-Terrorism Work Group.