Employers have the responsibility to protect the safety and health of their workers. Construction workers are exposed to a variety of health hazards every day. These men and women have the potential for becoming sick, ill, and disabled for life.
A course called “Health Hazards in Construction,” developed by the Construction Safety Council, Hillside, IL, can prepare an employer or its designated competent person to understand and react to occupational health hazards in construction. This column will present selected excerpts from the course workbook. You can contact the Construction Safety Council at http://www.buildsafe.org.
Course participants learn how to anticipate, recognize, evaluate and control occupational health hazards, which include chemical, physical, and biological hazards. These hazards are especially significant, because a worker’s exposure to hazardous materials on the job can unknowingly be brought back to the worker’s home. Heavy metals such as lead dust, concrete-crusted clothing, and a variety of oils, greases, and solvents can all unintentionally poison a family. So workers have a responsibility to wear personal protective equipment (PPE), practice good hygiene and take advantage of appropriate training programs.
Industrial hygiene is the art and science of anticipating, recognizing, evaluating, and controlling workplace conditions that may cause workers’ injury or illness. Industrial hygienists use personal and environmental monitoring and analytical methods to detect the extent of worker exposure and employ engineering, work practice controls, and other methods to control potential health hazards.
Scientists have been aware of industrial hygiene since ancient times. In the fourth century B.C., Hippocrates noted lead toxicity in the mining industry. In the first century A.D., Pliny the Elder devised a face mask made from an animal bladder. Much later, about 1700, Bernardo Ramazzini, the “father of industrial medicine,” published De Morbis Artificum Diatriba (The Diseases of Workmen).
Chemical hazards in construction include gases, vapors, fumes, dusts, fibers, and mists. Physical hazards come in several forms-temperature, noise, repetitive motion, awkward postures, and ionizing and non-ionizing radiation. Biological hazards include fungi (mold), bloodborne pathogens, bacteria, poisonous plants, and poisonous and infectious animals.
As part of your job as a construction manager or worker, study and learn the hazardous effects of the substances that you work with. Study the dangers associated with the chemical, physical, and biological hazards in construction. Toxicology is the science that studies the poisonous or toxic properties of a substance. The basic assumption of toxicology is that there is a relationship among the dose, or amount; the concentration at the affected site, and the resulting effects.
Generally, hazards associated with a particular job are either inherent (present before the worker shows up); or are created by the work, such as with welding and cutting, use of fuel-powered equipment, etc. To anticipate hazards, workers should survey the job-site conditions and be aware of the actions and behaviors of all other workers-even if they belong to another employer.
Hazardous conditions that can be anticipated on construction job sites include the following:
- Confined or enclosed spaces (hazardous atmospheres)
- Contaminated soil conditions
- Such unsanitary conditions as poor housekeeping or poorly kept toilet facilities
- Presence of hazardous materials such as dangerous coatings on structures and metal-containing alloys, concrete, and silica
- The use of hazardous chemicals such as gases, solvents, and glues
- The presence of residues left by degreasing agents, usually such chlorinated hydrocarbons as chloroform and carbon tetrachloride
- Older buildings and structures and unoccupied dwellings that can harbor fungi/mold, asbestos, and lead
- Extreme temperatures
- Radiological exposures at nuclear power plants, antennas, hospitals, laboratories, and the sun
- Loud noises (use of tools and equipment)
- The presence of plant or animal wildlife (e.g., poison ivy, poisonous venom in snakes, or rabies)
Recognition of Health Hazards
If you see visible clouds of vapor or particles, there may be a serious exposure problem. Remember, however, that most gases and vapors are invisible, and that often the most dangerous particles are too small to see.
If there is chemical dust on the ground or other surfaces, it probably got there by settling out of the air. If disturbed, settled dust can become airborne again. Watch for warning signs on labels and decals. Those are required by OSHA’s Hazard Communication Standard (29 CFR 1910.1200 and other applicable standards).
Do you smell or taste anything? If you smell a chemical, you are inhaling it. However, some chemicals can be smelled at levels well below those that are harmful. The odor threshold is the lowest level of a chemical that can be smelled by most people. If a chemical’s odor threshold is lower than the amount that is hazardous, the chemical is said to have good warning properties. It is important to remember that for most chemicals, the odor thresholds vary widely from person to person.
Some chemicals, like hydrogen sulfide, cause you to rapidly lose your ability to smell them. That is called olfactory fatigue. With these cautions in mind, knowing a chemical’s odor threshold may serve as a rough guide to your exposure level.
Never taste something that might be a hazardous chemical. However, if you inhale a chemical or accidentally get some in your mouth, it may have a particular taste that warns you that you’re being exposed.
Loud noises can severely damage your hearing, and you should wear appropriate hearing protection if exposed to excessive sound levels. Hand tools, power tools, heavy equipment, and blasting are all sources of noise in construction.
Do you feel immediate symptoms? When solvents are breathed in, they enter the bloodstream and travel to other parts of the body, especially the nervous system. The result can be dizziness, headaches, feelings of drunkenness, and tiredness. These symptoms can cause poor coordination, which can contribute to falls and other accidents.
Learn to recognize unsafe conditions and unsafe behaviors. These include not wearing appropriate Personal Protective Equipment such as gloves, respirators, chemical suits, hearing protection, etc. Watch for conditions where engineering or administrative controls have not been implemented. Such controls include adequate ventilation and dust collection systems. Learn and know that a hazard analysis has been completed if one is needed-air monitoring, dust sampling, noise metering, biological monitoring, and medical surveillance. Report safety violations and get them corrected!
Evaluation of Health Hazards
Environmental and personal air monitoring is one way to determine exposure to most chemicals. There are instruments to measure contaminates in the air-hazardous gases, vapors, fumes, dust/fibers and mists; also physical hazards such as noise, heat stress, and radiation.
Air monitoring must be done by a trained health professional-an industrial hygienist or technician. Monitoring can be done by measuring the air in a fixed location in the work area (area monitoring) or by placing the monitoring equipment on individual workers and measuring the amount they are exposed to (personal monitoring).
Personal monitoring is done to determine individual worker exposure, and area monitoring may be done to estimate possible exposure of a group of workers in a particular area. Monitoring is usually done during a specific time period, often as an eight-hour shift or 15-minute period, to ensure compliance with OSHA standards.
For chemicals that are absorbed by routes other than inhalation, such as through the skin or by ingestion, air monitoring may underestimate the amount of chemical absorbed into the body. To ensure accurate exposure assessment, medical surveillance is sometimes necessary. The levels of the chemical or its breakdown products in the body can be measured in the blood, urine, or exhaled air. Such testing is called biological
monitoring.
For several substances, biological monitoring is required by law when air monitoring results are above a certain level. Employers must maintain the results of these tests as employee records.
For information about setting up a class or obtaining a copy of the workbook, please contact Paul Satti, CHST, technical director, at the Construction Safety Council, 4100 Madison St., Hillside, IL 60162. Telephone 708-544-2082, X 213, or e-mail mailto:[email protected].
