Abrasive blasting is used to smooth and clean rough surfaces. It works by directing a high-velocity stream of an abrasive material, such as sand, crushed walnut shells, glass beads, dry ice, or baking soda, at a surface. First developed in the late 19th century, abrasive blasting is common to remove paint, chemical buildup, or contaminants from various types of surfaces.
There are several major health hazards associated with abrasive blasting. The most common include hearing loss, respiratory illnesses including silicosis, and secondary illnesses resulting from the substance being removed. For instance, if abrasive blasting is used to remove lead paint, the exposure precautions must be taken to limit the amount of lead workers are exposed to.
Adequate ventilation and respiratory protection is essential to prevent workers from injury. Other critical safeguards to take include regular vacuuming to minimize the amount of potentially toxic dust in the air, and the use of appropriate personal protective equipment, including a NIOSH-approved respirator, face protection, eye protection, a helmet, safety shoes, coveralls, and gloves.
In some cases, the abrasive blasting material itself can contain small amounts of toxic substances, such as cadmium. In some circumstances, it may be preferable for worker safety reasons to switch to a different, less toxic type of abrasive material.
Acetone, (CH3)2CO, is a common solvent, first discovered by alchemists during the Middle Ages, where it was known as "spirit of Saturn." In 1836, its chemical structure was determined by chemists Jean Baptiste Dumas and Justus von Leibig. In previous eras it was made from the distillation of starches. A key component in explosive manufacture during the First World War, acetone was so critical to the war effort that the British government paid schoolboys to find horse chestnuts to distill into acetone. Acetone is usually derived from fossil fuels in the modern era, by the petrochemical industry.
In addition to its common household uses, such as a cleaner and nail polish remover, acetone is used as an industrial degreaser, in the pharmaceutical industry, and in medicine, especially in dermatology. (Acetone mixed with alcohol is a common ingredient in skin peels.)
Acetone is not a carcinogen or a mutagen. Rather, its major hazard is its flammability. Acetone vapors are extremely flammable, and it must be carefully stored away from heat sources if used at the consumer level. An especially dangerous hazard results if acetone is combined with hydrogen peroxide; that mixture produces acetone peroxide, an unstable high explosive compound commonly used by terrorist groups. (Industrial and military users generally use safer, more stable explosives, such as TNT, Semtex, or ammonium nitrate-based explosives.)
Secondary hazards are generally limited to irritation from skin contact, eye contact, inhalation or swallowing. As anyone who has dealt with nail polish remover can tell you, the fumes can make you light-headed. Use protective gear as appropriate, including gloves, splash goggles, and vapor respirators.
Aerosol cans are everywhere, used for everything from insecticide to spray paint to cooking spray. The aerosol can was first invented in 1927 in Norway, but first deployed en masse during World War II, as aerosol cans of insecticide saved the lives of thousands of Allied soldiers in the Pacific Theater.
Aerosol cans contain both a payload and a propellant. The payload is the substance that the can distributes, such as insecticide, paint, or olive oil. The propellant is a pressurized gas that allows the payload into the air. In previous decades, the propellant was commonly chlorofluorocarbons (CFCs) which have been since banned due the damage they do to the ozone layer. They have been usually replaced by propane, butane, or isobutane, but some contain carbon dioxide, nitrogen gas.
Empty aerosol cans usually can be safely recycled, but discarded non-empty aerosol cans should be treated as hazardous waste. This is because propellants are dangerous, often flammable, and under pressure. (In addition to their uses as aerosol propellants, propane, butane, and isobutane are all highly flammable used as fuels.) Damaged or overheated aerosol cans can explode, causing a danger to life and property.
The other major hazard caused by aerosols is the product within the can. Insecticides, paint, and solvents may be dangerous to life and limb, and workers should take the necessary precautions associated with the product as well.
Asbestos is a fibrous mineral with incredibly useful properties that have been known since the Roman Empire. Charlemagne had an asbestos tablecloth; King Chosroes II of Persia had an asbestos napkin; and in the 19th and 20th centuries industrial-scale asbestos was used for everything from brake pads to lawn furniture to cement.
Asbestos has lots of advantages as a material: it's cheap, strong, lightweight, fireproof, and an excellent insulator. There's only one problem: asbestos fibers are horrifically toxic if inhaled.
The very same microscopic fibers that make asbestos so versatile also make it incredibly dangerous if those fibers get into the lungs. As early as 1924, British physicians made the direct connection between inhalation of asbestos fibers and respiratory failure, a disease called "asbestosis." Lawmakers on both sides of the Atlantic passed laws to improve ventilation in dusty workplaces over the 1930s and 1940s in response.
But this didn't end the story. Asbestos is also tied directly to mesothelioma, a particularly deadly form of lung cancer which only appears decades after exposure to asbestos. Over 90 percent of mesothelioma patients die within five years of diagnosis. Famous victims include actor Steve McQueen, who was exposed to asbestos both while serving in the US Marine Corps and during his motor racing career. (At the time, asbestos insulation was extremely common in ships, and auto racers would wear fireproof asbestos suits as protective gear.)
Worse yet, the companies involved in the asbestos industry knew about these hazards. And the industry concealed the dangers from the workers exposed to asbestos. This ultimately led to a flood of products liability and personal injury lawsuits which devastated the American asbestos industry, leading ultimately to the bankruptcy of Johns-Manville, then a Fortune 500 company and many other manufacturers. And in Italy, though the conviction was later overturned, billionaire Stephan Schmidheiny was convicted of voluntary manslaughter for his involvement in Italian asbestos workers' deaths.
This litigation is still ongoing-- as evidenced by the legions of asbestos lawyers still advertising on TV, the Internet, and the press. Asbestos is not a hazard, provided that its fibers don't become airborne-- but once asbestos fibers get airborne they become a dangerous carcinogen.
Benzene, C6H6, is a highly flammable, colorless liquid used in gasoline, as a laboratory solvent, and, most commonly, in the chemical industry. Benzene was discovered in 1825 by the English chemist Michael Faraday, under the name "bicarburet of hydrogen." Before the 1950s, benzene was produced from coal; in the modern era, benzene comes from the petrochemical industry.
Benzene is a health hazard and is everywhere. Since the 1940s, it has been well-known that there is no safe exposure level to benzene. Long-term exposure to benzene is linked to bone marrow failure, anemia, leukemia, and is a mutagen that damages DNA.
Breathing benzene vapors is the most common exposure path. Common industrial sources include the rubber industry, petrochemical industry, and in other places that use or process benzene. Other common non-industrial sources of exposure include car exhaust, gas stations, and tobacco smoke. Tobacco smoke is the most common source of exposure.
On rare occasions, low levels of benzene can be found in sodas. Benzoic acid, a common preservative, sometimes reacts with the Vitamin C in some drinks to produce low levels of benzene. (For comparison's sake, a contaminated 12-ounce soda exposes you to the same amount of benzene as a motorist filling up a gas tank.)
OSHA regulations limit benzene exposure to 5 parts per million for 15 minutes, or 1 part per million over 8 hours. When handling benzene, use personal protective equipment, such as face shields, protective clothing, and respiratory protection, as appropriate.
Falls are a major danger in the workplace, and distressingly common. In 2014, 261,930 workers missed at least one day of work from falls, according to the Labor Department. 798 workers died. Falls most commonly occur in the healthcare, retail, and wholesale industries, but the highest frequency of fall deaths occurs in the construction sector. According to the Centers for Disease Control, America spends roughly $70 billion is spent every year in medical costs and workers' compensation expenses due to falls. One in six workplace injuries that cause lost time are slips, trips, and falls.
Falls often result from poor lighting, uneven or obstructed surfaces, improper fall protection use, slippery surfaces covered in oil or water, and weather hazards. Bureau of Labor Statistics drop figures show that 15% of fatal falls involve a drop of of 10 feet or fewer; 59%, 11-30 feet; 17%, 31-50 feet; and 15%, of 51 or more feet. Older workers are especially vulnerable to fall deaths and injuries. Workers over 55 years old make up only 12% of the workforce but suffer 26% of workplace deaths, according to the Bureau of Labor Statistics. Falls cause more traumatic brain injuries among older workers than any other.
Employers are required to train employees that might be exposed to fall hazards. Careful cleaning, proper use of fall protection equipment, and ladder placement are all good ways to prevent fall injuries. When using fall protection equipment, always make sure that the harnesses are fitted correctly.