Specific Chemicals Guidelines

Hazardous chemicals used across the University research community may pose a wide range of health risks. Risk may result into health hazards ranging from minor irritation to major carcinogenicity and fertility damage. Physical hazards, such as flammability and reactivity, can also have serious consequences. This section provides information on best practices for the use and storage of specific chemicals for laboratories. 

Cal/OSHA regulations require all laboratories using hazardous chemicals to take specific safety measures to ensure safe lab operations. 

Guidelines for Safely using Formaldehyde

Formaldehyde is a colorless, strong-smelling gas commonly used in research as an aqueous solution for preservation. Formaldehyde is a sensitizing agent and is a known human carcinogen that is linked to nasal cancer and lung cancer. Acute exposure is highly irritating to the respiratory system and can cause headaches and eye and throat irritation at very low concentrations. Researchers can be exposed via inhalation when vapors escape into the workplace. Dermal exposure can happen when unprotected hands or bare skin come in contact with the liquid formaldehyde.  

The Occupational Safety & Health Administration’s (OSHA) Formaldehyde Standard (29 CFR 1910.1048) protects employee exposure to formaldehyde gas, its solutions, and materials that release formaldehyde. 

Researchers must always work with formaldehyde in a certified chemical fume hood with quantities above 0.1 mL. In addition, use non-latex gloves, such as nitrile or butyl when handling formaldehyde. Avoid contact of the eyes and skin with liquids containing one (1%) percent or greater formaldehyde. Do not reuse PPE and/or clothing that has become contaminated with formaldehyde before it is cleaned or laundered. Store contaminated PPE and clothing in containers labeled as: 

DANGER FORMALDEHYDE -CONTAMINATED (CLOTHING) EQUIPMENT AVOID INHALATION AND SKIN CONTACT  

EH&S Training Resources 

TC3750 is an online RASCAL training course available to employees who use formaldehyde (i.e. formalin) and/or paraformaldehyde. The course is designed to meet the training requirements of OSHA Formaldehyde Standard, 29 CFR 1910.1048 and is required for all users across the Columbia University who are exposed to greater than 0.1 ppm of formaldehyde and when a chemical fume-hood is not used.

Individuals over-exposed to formaldehyde shall be referred to Workforce Health and Safety (WHS) at Columbia University Medical Center or another healthcare provider for immediate medical consultation. The Principal Investigator/Supervisor should make employees familiar with the spill kit, its location and proper use. (For major spills call EH&S during regular work hours or Public Safety on campus during evening hours, weekends and holidays) 

The Principal Investigator/Supervisor is the primary contact and he/she shall establish appropriate procedures and communicate to their employees, how to handle emergencies minimizing injury. 

Employees working with quantities of formaldehyde greater than 0.1 mL outside of a certified chemical fume hood are required to contact EH&S at [email protected] to discuss exposure prevention methods. 

In addition, to maintain formaldehyde exposure below the limits established by the OSHA Standard 29 CFR 1910.1048, the EH&S occupational safety team can perform risk assessment upon request. The OSHA Permissible Exposure Limit (PEL) for formaldehyde is 0.75 ppm and the OSHA Short-Term Exposure Limit (STEL) is 2.00 ppm. The occupational safety team would perform risk assessment and if needed would perform exposure monitoring. The team would provide necessary guidance and recommend prudent work practices to minimize exposure level. 

Guidelines for Safely using Isoflurane

Isoflurane is the most commonly used halogenated anesthetic in animal research. It is a clear, colorless, volatile liquid at room temperature and pressure. Researchers can be exposed, via inhalation when vapors escape into the work environment during the administration of anesthesia.  

Vapors can escape into the work environment if leaking, unsealed or poorly sealed anesthetic systems are being used. Using a nose cone that do not form a tight seal or opening an active induction chamber to retrieve the subject also contributes to presence of waste anesthetic gas in the work environment. 

Although the relationship between overexposure to isoflurane and adverse health effects is not well-defined, most references in the occupational health literature recommends taking precaution to control exposure during animal surgical procedures. 

Safe work practices can reduce or eliminate potential exposure. These work practices include ensuring the proper function of the vaporizer (e.g., tight-fitting hose connections), the use of proper engineering controls (e.g., chemical fume hoods or snorkel trunks), to control fugitive vapor during procedures. Manufacturer’s recommendations should be followed for maintaining vaporizers. Typically, these should be calibrated at least annually. Hard ducted biosafety cabinets and chemical fume-hoods are the most favored choices for engineering controls. These systems have ventilation capability to efficiently capture fumes and exhaust them out of the work area, hence protecting the user. The user can place the entire gas mixing and delivery system into a certified chemical fume hood or a ducted biosafety cabinet. Downdraft tables and snorkel exhausts also serve the same function and can be used if placing the delivery system in an enclosed space is not practical.  

Researchers may prefer passive and active scavenging systems. Scavenging systems use activated charcoal to remove waste isoflurane gas. An efficient scavenging system can remove 90% of waste gases from ambient air. In addition to the scavenging system, researchers should perform anesthesia delivery in a well-ventilated room. 

A small chemical spill is the one that the laboratory staff is capable of handling safely without the assistance of safety and emergency personnel. In the event of a small chemical spill, use the following information for a safe cleanup process. 

  • Alert people in immediate area of spill. 
  • Open outside windows, if possible. 
  • Wear protective equipment, including safety goggles, gloves and long-sleeve lab coat. 
  • Avoid breathing vapors from spill. 
  • Confine spill to as small an area as possible.  
  • Do not wash spill down the drain
  • Use appropriate spill kits/sorbents to absorb spill. Collect contaminated materials and residues and place in container. Contact EH&S 212-305-6780 for proper disposal. 

EH&S is available to evaluate potential exposures and perform evaluations of vaporizing apparatuses upon request. Requests may be placed by completing the Hazard Assessment Form 

Isoflurane Policy

External Resources:   

Guidelines for Safely using Hydrofluoric Acid

Hydrofluoric Acid (HF) is an inorganic acid which is derived from dissolving hydrogen fluoride in water. HF is a noncombustible, colorless, fuming liquid or gas with a strong, irritating odor. HF readily dissolves in water to form colorless hydrofluoric acid solutions; dilute solutions are visibly indistinguishable from water. It is present in a variety of over-the-counter products at concentrations of 6% to 12%. 

All use of HF requires the presence of proper engineering controls. HF should always be handled inside a properly functioning chemical fume hood that is identified with signage indicating HF is used in the area. Before use, always confirm the fume hood is certified and working properly. 

NEVER STORE HF IN GLASS CONTAINERS! Hydrofluoric acid reacts with many materials therefore avoid contact with glass, concrete, metals, water, oxidizers, reducers, alkalis, combustibles, organics and ceramics. HF must be stored in tightly closed containers made of polyethylene. Secondary containment of polyethylene must also be used. Protect containers from physical damage. Storage facilities should have adequate ventilation and be constructed for safe containment of acids. 

Hydrofluoric acid is an extremely hazardous material. Lab personnel should utilize a buddy system and never work alone.  

Hand Protection: Heavy neoprene, thick nitrile rubber, or butyl gloves are best for working with HF (note that HF attacks natural rubber); however, the increased thickness of the gloves reduces dexterity, increasing the possibility of spills. Wear two pairs of nitrile exam gloves at a time, changing the outer pair often. When working with larger quantities of HF in procedures that do not require as much dexterity, wear heavy nitrile or neoprene rubber gloves, with a nitrile exam glove worn under the outer glove. Confirm that all glove lengths are sufficient to cover any exposed skin between the wrists and lab coat cuffs. 

Body Protection: When working with HF, wear clothing and personal protective equipment (PPE) that provides protection in the event of a spill: long-sleeved shirt, long pants, and closed shoes, in accordance with the University’s PPE Policy. Always wear a lab coat, chemical-resistant neoprene apron and sleeves. Do not wear shorts and sandals in laboratory.  

Eye Protection: Indirectly vented chemical goggles, along with a face shield, should be worn when handling HF to prevent eye/face exposure. 

Skin Exposure: Rapid decontamination is critical to minimizing/preventing injury. If exposure occurs, remove contaminated clothing and immediately wash the affected area with copious amounts of water for 5 minutes. Have someone else call for medical assistance during this time. It is critical to apply 2.5 % calcium gluconate first aid gel to affected areas after washing with copious amounts of water for a minimum of 5 minutes. Don a new pair of gloves in order to avoid secondary HF burns while applying the calcium gluconate gel. Anyone who provides assistance should also use the appropriate PPE. Calcium gluconate binds HF and prevents it from penetrating deeper into tissues. In the unfavorable situation where calcium gluconate gel is not available, flushing with water should be continued for 15 minutes or until emergency medical assistance arrives.  

Inhalation: Immediately remove victim to clean air until emergency personnel arrive on scene. Unlike external splashes, inhalation exposure is a serious medical emergency and is more problematic because there are no immediate decontamination procedures. Call for immediate medical assistance. Keep person calm until medial help arrives. 

Eye Exposure: Immediately flush eyes for at least 5 minutes with copious amounts of water, then switch to using 1% calcium gluconate solution as the flushing agent until emergency personnel arrive on scene. In case of unavailability of 1% calcium gluconate solution, keep flushing eyes with water until emergency medical assistance arrives. Do not use calcium gluconate gel on the eyes.

Guidelines for Safety working with Methylene Chloride

Methylene Chloride, also called Dichloromethane or DCM, is a halogenated solvent utilized in many laboratory and chemical processes such as liquid-liquid chromatography and organic syntheses, as well as for its general solvent properties.

Effective April 2024, the Environmental Protection Agency (EPA) under the Toxic Substances Control Act (TSCA) subjected methylene chloride to new regulations to protect users against the neurotoxic and carcinogenic effects of inhalation and dermal exposure. The new regulations establish an Existing Chemical Exposure Limit (ECEL) and Short-Term Exposure Limit (STEL) of 2 parts per million (ppm) as an 8-hour Time Weighted Average (TWA) and 16ppm as a 15-minute TWA, respectively.

Safe work practices can reduce or eliminate potential exposure to a chemical. If possible, consider eliminating the use of methylene chloride or replacing methylene chloride with a safer alternative. Resources regarding potential methylene chloride substitutions can be found in the links section at the end of this page.

If the elimination or substitution of methylene chloride is not feasible, engineering controls should be utilized to ensure minimal exposure. Work with methylene chloride should be performed in a chemical fume hood or glove box whenever possible. If a fume hood is not available or is not able to be used for a specific application, contact EH&S to assist in identifying alternative controls.

Many common glove materials do not provide strong protection from methylene chloride, including nitrile, latex, neoprene, and butyl rubber. At a minimum, double glove with nitrile or neoprene combination gloves when performing low risk work (i.e. pipetting and handing of mL scale quantities) with methylene chloride.  The double glove barrier will protect against momentary, incidental contact, but not significant contact or heavy exposure.

Gloves should always be changed frequently and whenever contamination occurs. 

Gloves of laminates of polyethylene (PE)/ethylene vinyl alcohol (EVOH), polyethylene vinyl alcohol, and ethylene vinyl alcohol (PVA/EVA), polyvinyl alcohol (PVA), Silver Shield, or another laminate resistant to methylene chloride are the preferred material type. These gloves should be used for any high-risk activity (i.e. pouring and other handling that is prone to splashing) or when working with high volumes of methylene chloride. Disposable gloves (e.g. nitrile, neoprene, etc.) can be layered over laminated gloves to protect the inner gloves and provide dexterity if needed.

A small chemical spill is the one that the laboratory staff is capable of handling safely without the assistance of safety and emergency personnel. In the event of a small chemical spill, use the following information for a safe cleanup process.

-Alert people in immediate area of spill.

-Open outside windows, if possible.

-Wear protective equipment, including safety goggles, gloves and a lab coat.

-Avoid breathing vapors from spill.

-Confine spill to as small an area as possible.

-Do not wash spill down the drain

For more information about what to do in the event of a chemical spill please refer to the Chemical Spills and Explosions page on the EH&S website.

EH&S is available to evaluate potential exposures and perform assessments of methylene chloride use. Labs should notify EH&S prior to starting work with methylene chloride and before changing protocols using methylene chloride. Requests may be placed by completing the Methylene Chloride Use Survey.  

External Resources:

EH&S is available to evaluate potential exposures and perform evaluations of vaporizing apparatuses upon request. Requests may be placed by completing the Hazard Assessment Form