Proper chemical storage is essential in assuring a safe work environment for students, staff, faculty, and visitors. These guidelines will help you store chemicals safely in your work place. For more detailed information, consult the UC Davis Chemical and Laboratory Safety Manual.

Inventory
Federal, state and local regulations require that the campus maintain a chemical inventory. To meet this requirement, Environmental Health and Safety has created a web-based Chemical Inventory System (CIS). The system is a user-friendly way to enter, update, and report chemical inventories.

Labeling
All chemical containers must be clearly labeled. These labels should include the chemical name, chemical manufacturer, major hazard(s), and date received and/or prepared. If a set of abbreviations is routinely used by the lab, please post in a conspicuous place the abbreviations and their meanings.

All hazardous waste containers must be clearly labeled with a UCD Hazardous Waste Label.

Storage
Chemicals must be stored with regard to compatibility and hazard classification. Storage areas must be clearly labeled. Laboratories must establish separate storage areas for each of the following:

• Flammable and combustible organic liquids and solvents,
• Corrosive inorganic acids,
• Dry poisons, dry salts and dry oxidizers,
• Corrosive bases,
• Corrosive organic acids such as trichloroacetic acid.

Cabinets or shelving should be sturdy and secured to the wall. Shelves should be fitted with a barrier or lip at least 1-1/2 inches high to prevent chemicals from falling off the shelves. Corrosives should be stored in wooden cabinets, if possible. Chemicals should not be stored under the sinks in a lab.

When you initially sort your chemicals for storage, cross-reference the Material Safety Data Sheets (MSDSs) for incompatibilities of each chemical with other chemicals in the laboratory. A list of incompatible chemicals is available from EH&S as SafetyNet #4, Partial List of Incompatible Chemicals.

Specific storage guidelines by chemical group are included at the end of this SafetyNet.

Ventilation
If a chemical cabinet or storage area is ventilated, the ventilation system must exhaust through the fume hood exhaust system duct or be independently ducted to the outside of the building. Cabinets shall not be ventilated through the fume hood work surface. Contact EH&S with questions about ventilation in your chemical storage area.

Spills
Keep absorbent material available to absorb spills and leaks. A good general-purpose liquid absorbent is available from the Storehouse (Safe Step Cat. No. 43900-101) or by mixing clay kitty litter with baking soda. Spill cleanup kits for solvents, acids, mercury, hydrofluoric acid, and other chemicals are available commercially. Prepare a spill response plan for your laboratory to control unplanned chemical releases. See SafetyNet #13, Guidelines for Chemical Spill Control.

Outdated Chemicals and Chemical Waste
Outdated chemicals and chemical wastes must be disposed by EH&S. A chemical waste disposal list form can be submitted electronically from the EH&S website. See SafetyNet #8, “Guidelines for Disposal of Chemical Waste”, for specific chemical disposal information.

Carcinogens
Regulated chemical carcinogens must be stored and handled in strict accordance with the UC Davis Chemical Carcinogen Safety Program. A list of regulated carcinogens may be downloaded or found in the UC Davis Chemical and Laboratory Safety Manual. Researchers wishing to use regulated chemical carcinogens must submit a Carcinogen Use Authorization to EH&S.

Smoking
Smoking is not permitted in outdoor areas where chemicals are used or stored in accordance with UC Davis P&P 290-10.

Specific Storage Guidelines by Chemical Group

Requirements for the storage of chemicals are detailed in the California Fire Code (CFC). The National Fire Protection Association Standards also has storage recommendations. Based on the occupancy rating of the space (the use of the space), the maximum allowable quantity of chemicals that can be stored in a given space is determined from the CFC. The types of cabinets and shelving required are also determined from the CFC.

Acids: This includes corrosive materials with a low pH such as: organic acids (e.g., acetic, boric and formic), and inorganic (mineral) acids (e.g., chromic, hydrochloric, sulfuric, nitric). Perchloric acid, when heated above room temperature, and hydrofluoric acid, because of their reactivity and toxicity, have special handling considerations.

1. Segregate organic acids from inorganic (mineral) acids. Many organic acids, like glacial acetic acid, are combustible and consideration should be given to storing combustible organic acids in a flammable liquid storage cabinet.
2. Segregate acids from bases and reactive metals such as sodium, potassium, finely divided magnesium, or zinc.
3. Segregate oxidizing acids, such as nitric, perchloric (heated above room temperature), and chromic from other mineral acids, organic acids, and combustible/flammable materials and liquids.
4. Segregate acids from cyanides and sulfides, such as sodium cyanide and iron sulfide that could liberate toxic gases upon contact.
5. Use bottle carriers, bins, tubs, buckets, or other secondary containment when transporting acids.
6. Store bottles of acid below eye level or in a cabinet specifically designed for storing corrosives. Laminated or epoxy-coated wooden cabinets with plastic-lined shelves are recommended for storing acids. Even purpose-designed metal cabinets and shelves will eventually degrade and potentially fail.
7. Store acid drums and carboys in a cool, dry place, away from direct sunlight and heat sources. Make sure spigots and liquid delivery devices are below eye level. Gravity feed, where a carboy is placed on an upper shelf and (potentially) hazardous liquid dispensed by gravity, is risky and should not be used.
8. Acid waste containers should be stored in non-metal secondary containment - a tub, bucket, tray, or tote - to contain leaks.

Bases: This includes corrosive materials with a high pH such as potassium hydroxide, sodium hydroxide, ammonium hydroxide, calcium hydroxide.

1. Segregate bases from acids.
2. Store solutions of inorganic hydroxides in polyethylene containers.
3. Use bottle carriers, bins, tubs, buckets, or other secondary containment when transporting bases.
4. Store containers of liquid bases below eye level or in a cabinet specifically designed for storing corrosives. Laminated or epoxy-coated wooden cabinets with plastic-lined shelves are recommended for storing bases. Even purpose-designed metal cabinets and shelves will eventually degrade and potentially fail.
5. Base waste containers should be stored in non-metal secondary containment - a tub, bucket, tray, or tote - to contain leaks.

Flammable and Combustible Liquids: This includes liquids with a low flash point and boiling point, such as acetone, toluene, xylene, hexanes, glacial acetic acid.

1. Quantities of flammable liquids greater than 10 gallons in any one room must be stored in a flammable liquid storage cabinet. This quantity may be doubled to 20 gallons, if metal safety cans are used for storage.
2. If flammable liquids need to be refrigerated, a lab-safe refrigerator, manufactured for storing flammable liquids, must be used. Do not store flammable liquids in standard, residential-type refrigerators.
3. Safety cans or drums dispensing or receiving flammable liquids must be grounded and bonded when transferring liquids.
4. Store flammable and combustible liquids separate from acids, bases and oxidizers.

Flammable Solids: This includes solid materials such as calcium carbide, phosphorus pentachloride, lithium, sodium, potassium, and finely divided metals (magnesium, zinc, iron) that may spontaneously ignite in air or on contact with water.

1. These materials react violently in the presence of water, including water vapor as humidity in ambient air. Toxic or flammable gases may be evolved or the material may catch fire on contact with air. Review MSDS', manufacturer's recommendations, and other references carefully for proper storage conditions.
2. Elemental lithium, potassium, and sodium must be stored under mineral oil.

Oxidizers: This includes solids and liquids with an oxidizing functional group (contributing oxygen to a reaction) such as benzoyl peroxide, potassium permanganate, hydrogen peroxide, nitric acid, perchloric acid (heated above room temperature), ammonium nitrate, potassium nitrate.

1. Segregate oxidizers from flammable/combustible liquids and solids. Flammable/combustible liquids and solids contribute fuel to the reaction. Oxidizers contribute oxygen to a reaction and can cause the reaction to rapidly get out of control.
2. Segregate oxidizers from reducing agents like hydroxylamine, sulfur dioxide, oxalic acid, alkali metals, and formic acid.

Highly Toxic and Sensitizing Compounds: This includes liquid and solid compounds such as cyanide, sodium azide, osmium tetroxide, toxins and venoms, isocyanates, phenol and phenolic compounds.

1. Carefully review MSDSs and other sources of hazard information BEFORE using these chemicals.
2. Make sure personal protective equipment is appropriate to the hazard, contacting the chemical manufacturer if necessary.
3. Make sure engineering controls, such as fume hoods and glove boxes, are in good working order, properly certified (within one year) and cleared of unnecessary clutter.
4. Under some circumstances, highly toxic compounds must be stored in a ventilated cabinet. Contact EH&S for advice.
5. Contact EH&S to determine if exposure monitoring is needed. For medical advice, contact Employee Health Services (530-752-2330).

Compressed Gases: 

1. Segregate and clearly mark “full,” “in service,” and “empty” cylinders.
2. Separate gases by hazard classification and compatibility.
3. Secure cylinders upright in a rack or chained with two straps or chains.
4. Replace valve caps when cylinders are not in use.
5. Do not use defective, damaged or unidentified gas cylinders. Remove from service and contact the manufacturer.
6. Use and store extremely hazardous gases only in ventilated safety cabinets. Depending on the gas, monitors, alarms, fire suppression, or other controls may be necessary. Contact EH&S for guidance.
7. Lecture bottles (small compressed gas bottles) must be labelled with chemical name, hazard(s), and date received. Segregate according to hazard class and chemical compatibility and in a secure place. Empty lecture bottles should be labeled, stored separately, and disposed through EH&S.
8. See SafetyNet #60, "Compressed Gas Safety" for additional information about safe handling of compressed gases.

Peroxide-forming Chemicals, such as diethyl ether, tetrahydrofuran, p-dioxane

1. Review SafetyNet #23, "Peroxide Formation in Chemicals" for detailed advice on safe handling of peroxide-forming chemicals.

For additional information, contact your EH&S Safety Advisor, EH&S at 530-752-1493 or ehsdesk@ucdavis.edu.


Reviewed/Revised. 05/2007
DMD