Subpart Z
Under 1910.1025AppA, “lead” means elemental lead, all inorganic lead compounds, and a class of organic lead compounds called lead soaps, and excludes other organic lead compounds.
The PEL under 1910.1025AppA is 50 micrograms of lead per cubic meter of air (50 µg/m3), averaged over an 8-hour workday.
Under 1910.1025AppA, the action level is 30 micrograms per cubic meter of air (30 µg/m3) as an 8-hour time-weighted average, and it triggers requirements such as exposure monitoring, medical surveillance, and training and education.
Under 1910.1025AppA, lead can enter the body primarily by inhalation (breathing) and ingestion (swallowing); skin absorption is not a common route for elemental or inorganic lead.
Under 1910.1025AppA, skin absorption is not a significant route for elemental lead and inorganic lead compounds covered by the standard; certain organic lead compounds not covered by this standard may be absorbed through the skin.
Under 1910.1025AppA, high short-term (acute) lead exposure can cause serious effects including acute encephalopathy, seizures, coma, and even death; other acute symptoms can include vomiting and rapid neurological decline.
Under 1910.1025AppA, long-term (chronic) lead exposure can damage the nervous, blood-forming, urinary (kidney), and reproductive systems, causing symptoms like fatigue, headaches, memory problems, peripheral neuropathy (e.g., wrist or foot drop), anemia, kidney disease, and reproductive problems.
Under 1910.1025AppA, the health protection goal is to keep worker blood lead levels at or below 40 micrograms per 100 grams of whole blood (40 µg/100g) for most workers over a working lifetime.
Under 1910.1025AppA, PbB is measured because it is the most useful indicator of how much lead is currently being absorbed into the body; it shows current absorption but does not directly measure lead already stored in tissues.
Under 1910.1025AppA, blood lead levels (PbB) are commonly reported in micrograms (µg) or milligrams (mg) per 100 grams (100g), 100 milliliters (100 ml), or per deciliter (dl); these units are essentially equivalent (1 mg = 1000 µg).
Under 1910.1025AppA, an elevated PbB over time implies increasing total body burden of lead and a growing risk of irreversible damage to organs and body systems—the longer PbB remains high, the greater the risk.
Under 1910.1025AppA, common occupations with lead exposure include primary and secondary lead smelting, lead storage battery manufacturing, lead pigment manufacturing and use, solder manufacturing and use, shipbuilding and repair, auto manufacturing, and printing.
Under 1910.1025AppA, behaviors that increase ingestion include handling food, cigarettes, chewing tobacco, or makeup with hands contaminated with lead, or otherwise placing contaminated hands or objects in the mouth.
Under 1910.1025AppA, lead can impair reproductive systems in both men and women, increase the risk of miscarriage, stillbirth, birth defects, and harm the developing fetus; workers who intend to have children should maintain blood lead levels below 30 µg/100g.
Under 1910.1025AppA, a common neurological sign of chronic lead exposure is peripheral neuropathy that can appear as a characteristic wrist drop or foot drop.
Under 1910.1025AppA, a worker should immediately notify their employer if they develop signs or symptoms of lead poisoning or if they want medical advice about the effects of current or past lead exposure on reproductive health; they should also report difficulty breathing during a respirator fit test or while wearing a respirator.
Under 1910.1025AppA, PbB measurements show the amount of lead currently circulating in the bloodstream but do not indicate how much lead is stored in body tissues (the body burden).
Under 1910.1025AppA, routine laboratory tests typically reveal lead-related kidney disease only after about two-thirds of kidney function is lost, meaning early kidney damage may be missed until it is extensive.
Under 1910.1025AppA, if a worker reports difficulty breathing during a respirator fit test or while wearing a respirator, the employer must make available appropriate medical examinations or consultations to evaluate the problem.
Under 1910.1025AppA, the standard focuses on PbB because blood lead reflects the amount of lead being absorbed and is directly linked to health risk—maintaining PbB below target levels (e.g., 40 µg/100g) helps prevent long-term damage that airborne measures alone may not fully capture.
Under 1910.1025AppA, children born to parents one of whom was exposed to excess lead are at higher risk for birth defects, developmental delays, behavioral disorders, or early death, so employers should prevent worker exposures and control take-home contamination.
Under 1910.1025AppA, a worker should immediately notify their employer if they develop signs or symptoms of lead poisoning or want medical advice about reproductive risks; the employer must provide appropriate medical examinations or consultations.
Under 1910.1025AppA, a PbB above 40 µg/100g indicates an increased risk of disease and requires intervention to reduce exposure and provide medical follow-up; the standard’s protection goals are set to avoid sustained PbBs above this level.
Under 1910.1025AppA, workers have a responsibility to learn about lead hazards and controls, follow required workplace practices (like hygiene and respirator use), report symptoms, and help ensure employer compliance with the standard.