CREATING HAZ-MAT CONTAINMENT TRAINING DEVICES
BY ALAN VEASEY
According to the OSHA standard regulating hazardous waste operations and emergency response (29 CFR 1910.120), hazardous materials technicians are responders who “approach the point of release in order to plug, patch, or otherwise stop the release of a hazardous substance.” Thus, technician-level training requires the incorporation of procedures and equipment that can be used to stop accidental releases (i.e., containment training).
An important component of training in containment is providing simulated releases for trainees to repair. The following information describes four devices used for containment training at the Workplace and Environmental Safety and Health Program at the University of Alabama at Birmingham/Center for Labor Education and Research (UAB/CLEAR).
SOME ASSEMBLY REQUIRED
All components of the devices described here, with the exception of the chlorine containers, are readily available through local sources such as hardware stores, plumbing supply houses, and industrial supply companies. The fabrication and modification required to create these devices involve minimal mechanical skills and commonly available tools. However, it is assumed that the reader has adequate mechanical skills and access to the tools. Thus, specific instructions on tasks such as fitting pieces of pipe together or drilling and tapping holes are not included.
As in all work activities, good safety practices should be strictly observed when creating training devices. For example, installing a fitting to pressurize a gas cylinder requires that a hole be drilled and tapped in the cylinder side wall. This procedure alone could involve hazards ranging from flying particles from drilling that could damage the eyes to chemical exposure, fire, or explosion should the cylinder contain residual product. Only personnel familiar with the appropriate safety procedures should perform these operations.
Leaking Pipe Stand
The pipe stand is a free-standing device assembled from water pipe. Galvanized metal pipe and fittings are recommended for strength, although PVC tubing can be used if weight is a concern. The incorporation of cam lever couplers allows easy disassembly for storage. The device can be supplied with water using a garden hose or any other suitable source.
Various points of release, and thereby repair operations, can be simulated with the pipe stand. For example, holes of various sizes and shapes can be drilled, cut, or ground into the pipes. Trainees are required to repair these holes using pipe repair clamps or improvised similar items. Likewise, leaks can be created by loosening connections or fittings. This requires that trainees use suitable wrenches to tighten the connections to stop the leaks. Other sources of release may be stopped simply by closing valves.
Items such as the pipe stand can be used to teach good operating procedures. For example, students can be shown that by placing a container below the gate valve and opening the valve before beginning repair operations, they can confine most of the spillage occurring during the operation while reducing the pressure on the leaks they are repairing, thereby minimizing their personal contamination.
One major advantage offered by a device such as the pipe stand is versatility. The size and type of pipes, fittings, and damage to them are limited only by the training objectives, student prerequisites, and trainer imagination. Also, the instructor can readily modify the device.
General Containment Training Device
The general containment training device (a.k.a. “leak monster”) is built from the tank of a junked 30-gallon electric hot water heater. This device is intended to allow practice in a variety of general plug/patch or leak repair operations.
Trainees are instructed to repair flowing leaks as they occur. A preassembled tool kit, from which they must select tools and equipment to use in repair operations, is provided. As existing leaks are stopped, new leaks appear as the water level inside the tank rises. As the device is used by CLEAR, trainees perform procedures such as the following to repair all leaks:
install a 112-inch pipe repair clamp over a large hole in the incoming pipe (which allows water to flow into the tank);
tighten bolts on the upper heater element mounting plate;
install a toggle plug through a small, circular hole in the side wall of the tank;
use chains and load binders to latch a gasket and metal-backing plate over a large, irregularly shaped hole in the side wall;
install a one-inch pipe repair clamp over a hole in the incoming pipe; and
install a fully opened gate valve onto a pipe nipple on top of the tank and then fully close the valve.
The tallest pipe attached to the tank contains six table-tennis balls. If all six steps are correctly executed, a surge of water should blow these balls out the top of the pipe as the gate valve is closed. This serves as a visual indication of a successful outcome.
150-pound Chlorine Cylinder
An actual 150-pound chlorine cylinder serves as the basis for this device. The cylinder was donated to UAB/CLEAR after being taken out of service by a local supplier. The cylinder can be pressurized to allow students to practice a variety of chlorine repair operations. The technique described here could also be used to pressurize a ton container.
The cylinder is pressurized with air through a fitting installed in the side wall. This requires that a hole be drilled into the tank and tapped to accept a 14-inch NPT fitting. For obvious reasons, it is critical to ensure that any container previously used to store hazardous materials is completely empty before drilling, cutting, welding, or doing anything else to the container. The fitting used by CLEAR for attaching an air line to the cylinder is a universal swivel fitting so that the hose always points downward for minimal interference.
For pressurization, CLEAR uses SCBA cylinders that supply air at approximately 2,200 psi. A two-stage regulator is used to maintain the cylinder pressure at 30 psi. A “T” in the airline allows the 150-pound cylinder and the one-ton container to be pressurized from the same regulator. All connections are fitted with quick-connect couplers for ease of assembly and disassembly. Reducing pressure with the regulator is important to decrease pressure-related hazards. However, even at the reduced pressure, instructors are present at all times during student activities to prevent students from taking unsafe actions, such as standing directly in front of fittings and unfastening them.
Students perform chlorine repairs in teams of two. Prior to the arrival of each team, the instructor operating the station ensures that several leaks are available for repair. Leaks can be simulated by loosening fittings (such as the fusible plug, packing nut, or outlet cap) and opening the valve. Likewise, the entire valve can be loosened slightly from the cylinder. Students are given a spray bottle with soap solution for detecting leaks. The bubbling of the soapy film over points of leakage substitutes for the use of an ammonia solution for leak detection in an actual chlorine repair operation.
Trainees are provided with a Chlorine Institute Series “A” emergency kit to use in repair operations. Initially, they use tools provided in the kit to stop leaks in the valve region by tightening connections or closing the valve. Afterward, the instructor removes the outlet cap, opens the valve, and instructs the team to proceed as if it has a leak that the previous methods would not stop. At this point, trainees are required to install the hood assembly provided with the “A” kit over the cylinder valve. Another option would be to equip the cylinder with a valve that intentionally had been damaged so that installation of the hood assembly would be required.
Chlorine Ton Container
The basis for this device is the head from a ton container mounted on a steel frame fitted with casters, carrying handles, and a hoisting ring. CLEAR purchased this item from a commercial supplier of chlorine training aids. Such a device is currently available with a water-line connection to the liquid valve and lower fusible plugs.
The vapor valve on the ton container training aid has been pressurized through an airline fitting installed in the upper eduction pipe. The device is pressurized from the same air supply and regulator used for the 150-pound cylinder.
The ton container head is used in much the same way as the 150-pound cylinder is used in training. Major exceptions are that the fusible plug arrangement is different and the Chlorine Institute “B” kit is required for ton-container repairs.
The same considerations related to pressure hazards discussed for the 150-pound cylinder apply for training operations involving the ton-container head. Similar safety precautions are required.
CONSIDERATIONS FOR IMPLEMENTATION
When training with these devices, as at all other times, the safety of trainees should be the utmost consideration. For example, when conducing training with pressurized containers, the pressure is regulated to a relatively low level, trainees are cautioned, and instructors observe carefully to be sure that trainees do not take actions that might put them at risk. Also, area safety hazards, such as muddy footing conditions, can occur when training with the devices that use water.
The devices described here are versatile in that they can be used in simple exercises to teach basic containment skills or be incorporated into complex exercises such as mock incidents. However, training objectives must be given full consideration anytime devices such as these are implemented into a training program. None of these devices are intended for training below the technician level.
Prerequisites are also an important consideration. Trainees in UAB/CLEAR`s current technician update course are required to repair leaks on three different devices (the general containment training device, the 150-pound chlorine cylinder, and the one-ton chlorine container head) while wearing a level B ensemble of personal protective equipment (PPE). All trainees have had previous training and experience in conducting repair operations while wearing protective gear. However, the same exercise could be used in initial technician-level training if all requisite objectives (such as containment procedures and use of PPE) were covered earlier in the course.
The designs of the devices included in the article were adapted for the most part to the equipment and supplies readily available to UAB/CLEAR. The plans are intended primarily as examples and can be modified as needed to incorporate available components and address the trainer`s specific objectives. In all cases, the ultimate goal is to produce devices that allow trainees to practice the types of containment procedures they may be called on to perform during actual emergency operations. n
ALAN VEASEY is curriculum coordinator for the Workplace and Environmental Safety and Health Program operated by the Center for Labor Education and Research at the University of Alabama at Birmingham (UAB/CLEAR). He has a master?s degree in education and currently is completing a master?s degree in occupational health and safety. UAB/CLEAR provides training for hazardous-waste site remediation and hazardous-materials emergency response and receives financial support from the National Institute for Environmental Health Sciences (NIEHS).
ALAN VEASEY is curriculum coordinator for the Workplace and Environmental Safety and Health Program operated by the Center for Labor Education and Research at the University of Alabama at Birmingham (UAB/CLEAR). He has a master`s degree in education and currently is completing a master`s degree in occupational health and safety. UAB/CLEAR provides training for hazardous-waste site remediation and hazardous-materials emergency response and receives financial support from the National Institute for Environmental Health Sciences (NIEHS).