Subpart Z
Use a personal sampling pump at a flow rate of 2 liters per minute for full-shift sampling of airborne inorganic arsenic. This is the sampling flow rate specified in Appendix B to 1910.1018 for personal, full-shift samples.
A full-shift air sample for arsenic should be collected for at least 7 hours. Appendix B to 1910.1018 specifies that samples collected should be full shift (at least 7-hour) samples.
Collect particulate inorganic arsenic on a 0.8 micrometer pore size membrane filter, 37 mm diameter. Appendix B to 1910.1018 specifies using a 0.8 µm membrane filter (37 mm diameter) for sampling.
Collect volatile arsenicals using a midget bubbler containing 15 mL of 0.1 N sodium hydroxide (NaOH). Appendix B to 1910.1018 recommends using a midget bubbler filled with 15 mL of 0.1 N NaOH for volatile arsenicals like arsenic trichloride.
The sampling and analysis method should have an accuracy of not less than ±25 percent (with a 95% confidence limit) at 10 µg/m3. Appendix B to 1910.1018 specifies this accuracy requirement for 10 micrograms per cubic meter of air.
For inorganic arsenic concentrations between 5 and 10 µg/m3, the method of sampling and analysis should have an accuracy of not less than ±35 percent with a 95% confidence limit. See Appendix B to 1910.1018 for this requirement.
Personal sampling is required for exposure assessment; Appendix B to 1910.1018 specifies sampling with a personal sampling pump, indicating the intended method is personal sampling rather than only area sampling.
Use a personal sampling pump set to 2 L/min with a 0.8 µm pore size, 37 mm membrane filter for particulates; for volatile arsenicals, use a midget bubbler with 15 mL of 0.1 N NaOH. These are the recommended procedures in Appendix B to 1910.1018.
No; arsenic, arsenic trioxide, and arsenic trichloride are described as nonflammable. Appendix B to 1910.1018 lists them as nonflammable in the fire data section.
Heat is identified as a condition that contributes to instability for arsenic compounds, and certain incompatibilities exist. Appendix B to 1910.1018 notes that heat contributes to instability and that hydrogen gas can react with inorganic arsenic to form the highly toxic gas arsine.
Employers should avoid allowing hydrogen gas to contact inorganic arsenic because hydrogen can react with inorganic arsenic to form arsine, a highly toxic gas. Appendix B to 1910.1018 identifies this incompatibility explicitly.
Arsenic trichloride has a vapor pressure of about 10 mm Hg at 23.5°C and a boiling point of 130.2°C, indicating it is volatile at room temperature and can generate airborne vapors that require controls. Appendix B to 1910.1018 provides these physical properties, which inform the need for ventilation, capture, and appropriate sampling (e.g., using a bubbler for volatile arsenicals).
Arsenic trioxide has limited solubility in water—about 3.7 grams per 100 cc at 20°C—so it persists as a particulate under many conditions and requires controls for dust and inhalation exposure. Appendix B to 1910.1018 lists this solubility value in the physical properties section.
Use a 0.8 micrometer pore size membrane filter, 37 mm diameter; the fine pore size captures respirable and inhalable arsenic particulates effectively for quantitative analysis. Appendix B to 1910.1018 specifies 0.8 µm, 37 mm filters for sampling.
The accuracy requirements (±25% at 10 µg/m3 and ±35% for 5–10 µg/m3) must be met with a 95 percent confidence limit. Appendix B to 1910.1018 sets these accuracy and confidence requirements for sampling and analysis.
Appendix B recommends full-shift samples (at least 7 hours) for exposure assessment; it does not specify short-term sampling procedures, so use full-shift personal sampling as the default method and consult 1910.1018 or an analytical laboratory for validated short-term methods. See Appendix B to 1910.1018 for the recommended full-shift approach.
For nonvolatile inorganic arsenic particulates, collect on a 0.8 µm membrane filter (37 mm) using a personal pump at 2 L/min; for volatile arsenicals (e.g., arsenic trichloride), use a midget bubbler with 15 mL of 0.1 N NaOH to trap vapors. Appendix B to 1910.1018 distinguishes these collection methods.
Because health-based limits for arsenic are expressed in low micrograms per cubic meter, methods must be accurate at those levels (±25% at 10 µg/m3 and ±35% at 5–10 µg/m3 with 95% confidence) to reliably determine compliance and health risk; this requirement is specified in Appendix B to 1910.1018.
Contact between inorganic arsenic and hydrogen can form arsine, a highly toxic gas; workplaces should control sources of hydrogen, segregate incompatible chemicals, and use engineering controls to prevent contact. Appendix B to 1910.1018 explicitly notes this incompatibility and the danger of arsine formation.