Monthly Lab Safety Officer Meeting Updates: Hazardous Mineral Acids Overview

Monthly Lab Safety Officer Meeting January 31st, 2025

Agenda 1. Announcements a) Change of LSO Form https://forms.gle/BsQQuzsK5F7c3kqq6 b) Reporting Incidents to DRS Phone: 217-333-2755 Email: drs@illinois.edu Submit an Event Report: https://forms.illinois.edu/sec/1674176205?referrer=https://shibboleth.illinois.edu/ c) Anonymous Near Misses and Incidents Form for the JST https://forms.gle/88wVJ8gHXFoMqBtw5 2. Open Discussion Facilities Issues/Updates 3. Recent Near Miss/Incident Reports No incident submitted this month 4. Safety Minute Mineral Acids Hazards and Safe Practices 2

Open Discussion/Facilities Updates Any facilities issues or updates Safety concerns or comments? Suggestions for future meeting topics? 3

Mineral Acids - Hazards Water soluble acids derived from inorganic minerals Highly corrosive to the skin and eyes Reacts violently with water and bases in exothermic reactions Irritant (skin and eye) Skin Sensitizer Acute Toxicity (harmful) Oxidizer Skin Corrosion/Burns Eye Damage Corrosive to Metals Acute Toxicity HCl, H2SO4, HNO3 4

Hydrochloric Acid (HCl) Conc. HCl is 38% (w/w) or 12 M hydrogen chloride (HCl) in water It has a pungent odor and is corrosive to the respiratory system and eyes When mixed with an oxidizer such as sodium hypochlorite (bleach) or potassium permanganate, it will evolve toxic chlorine gas keep away from strong oxidizers! OSHA Hazard Communication Standard: 1 most hazardous, 4 least hazardous 5

Sulfuric Acid (H2SO4) Conc. H2SO4 is ~98% (w/w) or 18 M sulfuric acid in water Very strong dehydrating agent, chars materials made from carbohydrates, such as cotton, paper towels, and wood, by dehydration do not add paper towels to spills! Concentrated sulfuric acid reacts violently with many organic chemicals Causes extremely severe skin burn OSHA Hazard Communication Standard: 1 most hazardous, 4 least hazardous 6

Nitric Acid (HNO3) Nitric acid is supplied as concentrated acid (68-70%, 16M), fuming strength (>86%), and as anhydrous form (100%). It is a strong oxidizer even when fairly dilute and at room temperature. Oxidizes most organic compounds while it is reduced to nitrous fumes. Decomposition can lead to the release of toxic gases and vapors (NOx) OSHA Hazard Communication Standard: 1 most hazardous, 4 least hazardous 7

Storage Store acids in an acid cabinet, preferably in secondary containment. Keep away from bases and chemicals that will liberate toxic gas if in contact with acid, such as azides, bleach, carbides, cyanides, nitrides, sulfides, and metals. Mineral acids should be stored separately from bases, oxidizing agents, organic materials, and combustible materials. Nitric acid must be stored separately from organics, including acetic acid. 8

Safe Handling At all times when handling acids, wear at a minimum standard laboratory attire: closed-toe shoes, long pants, a lab coat, safety glasses, and gloves. When handling large amounts (>500 mL) or when splashing is more likely, wear additional protection to prevent skin contact: A face shield above splash goggles, acid-resistant gloves with long cuffs, and an acid-resistant apron or smock. Always handle concentrated acids in a fume hood to avoid breathing in vapors of the acid or evolving gases. If possible, work in secondary containment to contain spills. Always dilute by adding acid to water and not water to acid. Adding water to concentrated acid may cause violent boiling of the solution and splashing. Solutions of 3 M or less can be handled on a bench top, but keep in mind that they are still corrosive. Work in secondary containment when possible. 9

Waste Disposal Keep acid waste separate from other waste streams and use secondary containment for the waste container. Check the waste solution for evolving gases before pouring it into a waste container. Over- pressurization of closed waste containers has led to violent container ruptures in the past. Accidental adding of HNO3 to waste containing organic materials fire and explosion many major lab accidents!! If the waste solution does NOT contain any hazardous metals, consider elementary neutralization. Depending on the content the neutralized solution can be poured down the drain or submitted to DRS. DRS guideline for neutralizing acid solution: Pour the acid waste into a large quantity of ice (500 grams of ice per 100 mL of acid). Neutralize the mixture with an aqueous basic solution, such as 1M or 10% sodium hydroxide (NaOH) or saturated sodium bicarbonate (NaHCO3) in water until the pH is neutral. The neutralized solution may then be poured down the drain. If the neutralized mixture contains heavy metals (e.g., gold, platinum, lead, chromium), the solution should be labeled and disposed of through the chemical waste management system. 10

Handling Spill Have a spill kit readily available before working with any concentrated acid. Neutralize using NaHCO3 or CaCO3 by spreading that on the spill, then sweep up the neutralized material using a broom, adsorbent pads In the case of a large spill of fuming acid (e.g., conc HCl) outside the hood, or if the spill cannot be contained, evacuate the area immediately, alerting others nearby. Close the door and keep people from entering. Call 911 immediately. 11

Emergency Response Skin Contact: Remove contaminated clothing and rinse the affected skin immediately with copious amounts of water for 15 minutes or until pain is relieved. If skin irritation is visible, seek medical attention. Eye Contact: Use the eye wash to rinse the eye thoroughly for at least 15 minutes, occasionally lifting upper and lower eyelids and rolling the eyeballs. Seek medical attention. Inhalation: Move into fresh air immediately. Seek medical attention. Ingestion: Do not induce vomiting. Rinse the mouth with water. Seek medical attention. Provide the medical team with the Safety Data Sheet SDS for the acid. 12

References https://drs.illinois.edu/Page/SafetyLibrary/MineralAcids MSDS from Fisher Scientific https://www.ehs.harvard.edu/node/7719 13

Thank you for coming! Please forward LSO meeting recap email/slides to your group! We can stay for a few minutes if there are further questions. We are taking attendance based on the participant list! No need to sign in. 14