The hazardous waste environment is typically an uncontrolled situation where virtually any kind of problem affecting people or the environment can occur. Improper control and handling of the hazardous substances can result in very dangerous results. The situation is further complicated by the fact that there may be hundreds or even thousands of chemicals at the site and they may interact and become even more dangerous to the workers. These individuals are not only stressed by direct exposure but also by the disorderly physical environment and having to wear protective clothing for long periods of time. The combination of all these factors may result in immediate and obvious health and safety problems or long-term problems.

Workers at hazardous waste sites may be exposed to: toxic chemicals, fire and explosions, states of oxygen deficiency, ionizing radiation, biological hazards, safety hazards, electrical hazards, heat stress, cold exposure, and extreme noise. The exposures may be to individual hazards or multiple hazards at the same time, which enhances the potential for disease and injury and possibly even death.

Toxic chemicals may be present in gaseous, liquid, or solid states. They may enter the body through inhalation, ingestion, a puncture wound, or skin absorption. They may cause acute effects which will result in almost immediate symptoms, or chronic effects which may be an accumulation of low concentrations of the chemicals over time. Some chemical effects may be temporary and reversible and others permanent depending on the chemical, time and concentration of exposure, and the individual. Cancer or respiratory diseases are some of the serious side-effects which may occur and may not be seen for many years. Disease potential may depend on the chemical, its concentration, its route of entry, length of exposure, and personal factors such as smoking, consumption of alcohol, medications taken, nutrition, age, and sex. Inhalation is an extremely serious route of entry into the body as well as direct contact of the skin and eyes with the hazardous material.

Explosions and fires can occur spontaneously. However, it is typically the movement of containers of the chemicals or the mixing of incompatible chemicals that causes explosions and fires to occur. The hazards created in addition to those already noted above concerning exposure to toxic chemicals include intense heat, smoke inhalation, open flames, and flying objects.

Diseases caused may include infections, allergies, respiratory conditions, cancers, communicable diseases, and chronic disabilities. Diseases may be spread by food, water, air, animals, vectors, skin contact, and inhalation.

Injuries may occur as a result of damage to joints, fractures, puncture wounds, damage to eyes and ears, sprains, strains, and damage to the skin. Unstable wastes, heavy wastes, cave-ins at disposal sites, fires, explosions, improper processing equipment, and inadequate training of operators may be the cause of injuries. Other concerns are sharp objects, slippery surfaces, steep grades, uneven terrain, and unstable surfaces such as walls or flooring within the disposal area.

Oxygen deficiency occurs when there is less than 16% oxygen in the environment. This may affect the level of attention to surroundings and conditions, judgment, and coordination, and causes nausea, vomiting, brain damage, heart damage, unconsciousness, and death. Typically, this occurs when another gas replaces oxygen within the environment or the individual is working in confined or low-lying spaces.

Radioactive materials may produce alpha particles, beta particles, and gamma rays. Alpha particles can be hazardous if ingested or inhaled. Alpha particles have limited penetration and are stopped by clothing and the outer part of the skin. Beta particles can cause burns to the skin and damage the subsurface blood system. They are also dangerous if inhaled or ingested. Gamma rays pass through clothing and human tissue and cause serious permanent damage to the body. Protective clothing is not effective. (See endnote 94.)

There are numerous electrical hazards from overhead power lines to downed electrical lines, and buried cables which may be cut by heavy equipment when digging up land.

Heat stress is especially significant for people wearing protective clothing. The body is unable to get rid of heat and moisture in an effective manner when enclosed in the personal protective equipment that is used to protect the worker from various hazards at the disposal site. The problem can occur in as little as 15 minutes. Heat stress may cause rashes, cramps, and drowsiness, and impair the individual’s ability to function and think clearly. Cold exposure may occur when the individuals are exposed to low temperatures and a significant wind which results in a low wind-chill factor.

Noise is created by the large equipment being used and can easily startle the workers or distract them. Physical damage may occur to the ear and result in pain and temporary or permanent hearing loss. The interference with communications can prevent the individual from being alerted to a dangerous situation.

Best Practices in Mitigation of Occupational Health and Safety Problems

  • • Establish a risk assessment process within the facility based on good industry knowledge and experience of actual problems within the overall field of endeavor. Pay special attention to the problems and needs of: young workers and older workers; pregnant and nursing women; migrant workers; untrained or inexperienced workers; and individuals involved in maintenance, members of the community, and special contractors.
  • • Develop and implement a comprehensive occupational health and safety plan for all workers in all departments based on specific hazards, means of prevention and mitigation, employee training, environmental controls, and proper supervision and management of personnel.
  • • Eliminate known hazards when possible and mitigate the effects of those that cannot be eliminated.
  • • Develop a special permit-to-work system for those types of high risk jobs which need special personnel who are physically fit, highly trained and experienced, have excellent judgment, and are good workers. There may be a permit system for hot work, cold work, electrical work, confined spaces, complex equipment, isolation areas, radiation, etc.
  • • Conduct job safety analyses to determine potential critical situations which could lead to disease and injury for all positions within the facilities in order to be able to establish appropriate standard operating procedures, use of personal protective equipment, necessary training, and appropriate supervision.
  • • Determine the concentrations of the different types of hazards as well as the amount of time of exposure that the workers encounter in any operation whether it is hazardous materials handling, hazardous waste handling, or non-hazardous waste handling.
  • • Use special safety lockout procedures to make sure that equipment cannot start operating when a maintenance worker is performing an assignment on it.
  • • Especially during shutdowns and maintenance work, ensure that all vessels are emptied and the workers, using a buddy system, are wearing appropriate personal protective equipment including respiratory devices.
  • • Have all testing equipment fully calibrated and checked and then utilized during the cleanup process to make sure that hazardous chemicals are not entering the air and causing potential serious injury to workers.
  • • Determine if the equipment is cool enough to work on before providing any type of maintenance.
  • • Recognize the potential for occupational hazards due to continuous hot work or working in confined areas where hazardous substances have been stored. Use special precautions to prevent worker fatigue, disease, and injury.
  • • Minimize the amount of highly volatile and poisonous substances that is kept in storage in the facility.
  • • Reduce the amount and frequency of transfer of highly hazardous substances within the facility.
  • • Reduce and minimize the levels of toxicity or infectivity of the materials and increase the level of safety of the workers by use of appropriate personal protective equipment, necessary ventilation devices, and limitations of time of exposure to the substances.
  • • Utilize rigorous workplace monitoring and competent supervisory control of all activities and personnel.
  • • Install gas detectors in hazardous areas which will give immediate indication of leaks and potential disastrous results.
  • • Use select barrier creams especially when exposed to aromatic hydrocarbons.
  • • Remove all potential sources of ignition where flammable or explosive materials are being processed, used, or stored.
  • • Produce, store, use, and transport acids with the greatest care and continuous monitoring as well as an alarm detection system because of the extremely corrosive and hazardous materials involved. Only use specially trained workers.
  • • Conduct a noise and vibration survey to determine where the problems occur and provide necessary personal protective equipment as well as limit the time of exposure of workers.
  • • Provide automatic alarms and shut-off systems where problems occur with machinery and if safety devices have been altered or removed.
  • • Establish areas for workers to walk away from moving vehicles. Ensure that all walkways are made of non-slip materials.
  • • Control entry into all enclosed areas and areas of production, storage, and transportation of hazardous chemicals. All individuals entering these areas must have appropriate training and personal protective equipment. They must be closely supervised and use the buddy system.
  • • Provide first-aid equipment and emergency showers in the event of spills or other accidents. Make sure that water usage by the individuals will not contribute to the problem.
  • • All workers should have physical examinations before working with hazardous materials and periodic follow-ups. The examinations should include all necessary laboratory tests.
  • • If a worker is exposed to a hazardous material, the individual should be immediately decontaminated and examined by appropriate medical authorities as well as given necessary tests to determine levels of contamination. Proper treatment should start immediately and be closely followed by medical personnel.
  • • Employees working with hazardous materials should be kept to a minimum and special precautions should be taken including: limited time exposure by individuals, regular cleaning of contaminated surfaces, proper maintenance of all equipment by specialists, use of personal protective equipment, and prohibiting all eating, drinking, and smoking in hazardous materials areas. Further, facilities should be provided for showers and changes of clothing before the individual leaves the industrial complex.
  • • Special precautions should be taken around all moving parts of machinery to avoid contact with clothing or the individual.
  • • Do not wear contact lenses in contaminated areas.
  • • Never allow a worker to go into a confined space or low-lying area alone and ensure that the individual has proper personal protective equipment as well as a secure communications system within the equipment. These individuals need to be closely supervised and only allowed to work within the confined environment for brief periods of time.
  • • Determine if radioactive material is emitting alpha, beta, or gamma rays. Alpha radiation can be stopped by protective clothing. It must never be inhaled or ingested. Beta radiation can cause serious burns to the skin and damage the blood system. It must never be inhaled or ingested. Use protective clothing and complete and total personal hygiene and decontamination efforts to prevent problems. Gamma radiation will pass through clothing and human tissue and can cause serious damage to the body. Chemical protective clothing will not help. Use respiratory equipment and other protective equipment to keep the individual from inhalation, ingestion, injection by accident, or skin absorption of alpha and beta radiation. If the radiation level is above 2 mrem per hour, shut down the site and have a health physicist evaluate the potential hazards to workers.
  • • All biological hazards should be destroyed before sending the material to any landfill site. However, workers are still subject to contact with poisonous plants, insects, or animals which may spread disease to them.
  • • Employees should be constantly checking for potential safety hazards on-site, avoiding them, and immediately notifying their supervisors concerning the situation.
  • • Employees should be aware of electrical hazards and have information concerning all buried cables to avoid cutting them during any type of excavation or other work.
  • • All work should cease during electrical storms and weather conditions should be monitored very closely.
  • • All workers wearing personal protective equipment must be closely supervised to make sure that they are not suffering from heat stress. They should be immediately removed from the environment and taken to a cool place and allowed to rest before resuming work. During the work there should be frequent breaks for these individuals.
  • • All workers should be protected against cold injury by removing them to a proper place to warm up, especially when the wind-chill factor is very low. Proper warm clothing in layers should be worn.
  • • Employees should not be subjected to more than 90 dB on the A-weighted scale without proper means of ear protection and should not be allowed to stay within the very noisy environment for long periods of time.
  • • Since each portion of the hazardous waste site varies from other portions depending on the chemicals and other hazardous materials being stored and processed, always evaluate temperature at the site which if high may increase the vapor pressure of most chemicals; wind speed and direction; amount of rainfall, diversion tactics, and levels of water in a given area; amount of moisture present which could affect the process or, if limited, increase the amount of dust; actual vapor emissions; and the types of work activities being carried out.
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