Standard Operating Procedures
Laboratory Specific
Chemical: Picric acid
Please fill out the form completely. Print a copy and insert into your
Laboratory Safety Manual and Chemical Hygiene Plan.
Refer to instructions for assistance.
_____________________________________________________________________________
Department:________________________
Date when SOP was written:_______
Date when SOP was approved by the lab supervisor: ___________________
Principal Investigator:___________________________________________________
Internal Laboratory Safety Coordinator/Lab Manager:___________________________________
Laboratory Phone:____________________ Office Phone:_____________________
Emergency Contact:____________________________________________________
(Name and Phone Number)
Location(s) covered by this SOP:__________________________________________
(Building/Room Number)
_____________________________________________________________________________
Type of SOP:
Process
Hazardous Chemical
Hazardous Class
Purpose
Picric acid is the chemical compound formally called 2,4,6-trinitrophenol (TNP). This yellow
crystalline solid is one of the most acidic phenols. Like other highly nitrated compounds such as
TNT, picric acid is an explosive. Its name comes from Greek πικρος (pik' ros), meaning "bitter",
reflecting the bitter taste of picric acid.
By far the largest use has been in munitions and explosives. It has found some use in organic
chemistry for the preparation of crystalline salts of organic bases (picrates) for the purpose of
identification and characterization.
In metallurgy a picric acid etch has been commonly used in optical metallography to reveal prior
austenite grain boundaries in ferritic steels. The hazards associated with picric acid has meant it
has largely been replaced with other chemical etchants.
Bouin solution is a common picric acid-containing fixative solution used for histology specimens.
Workplace drug testing utilizes picric acid for the Jaffe Reaction to test for creatinine. It forms a
colored complex that can be measured using spectroscopy.
Picric acid emits a high-pitched whine during combustion in air and this has led to its widespread
use in fireworks.
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Physical & Chemical Properties/Definition of Chemical Group
CAS#:
88-89-1
Class:
Flammable, explosive when dry and Toxic
Molecular formula:
C6H3N3O7
Boiling Point:
> 300 C (Explodes)
Melting Point:
121oC
Decomposition Temperature:
Not available
Potential Hazards/Toxicity
EMERGENCY OVERVIEW: Flammable. Toxic. Explosive when dry. Forms very sensitive
explosive metallic compounds. Toxic by inhalation, in contact with skin and if swallowed. May
cause sensitization by skin contact. Readily absorbed through skin. Target organ(s): Blood.
Kidneys.
Highly important danger information!
Modern safety precautions recommend storing picric acid wet. Dry picric acid is relatively
sensitive to shock and friction, so laboratories that use it store it in bottles under a layer of water,
rendering it safe. Glass or plastic bottles are required, as picric acid can easily form metal picrate
salts that are even more sensitive and hazardous than the acid itself. Industrially, picric acid is
especially hazardous because it is volatile and slowly sublimes even at room temperature. Over
time, the buildup of picrates on exposed metal surfaces can constitute a grave hazard.
Target Organs: Blood, kidneys and liver
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Potential Health Effects:
Eye: May cause eye irritation.
Skin: May cause skin irritation. If absorbed, causes symptoms similar to those of ingestion. May
cause sensitization by skin contact.
Ingestion: May cause irritation of the digestive tract. May cause liver and kidney damage. May
cause headache. May cause tremors and convulsions. May cause unconsciousness. May cause
blood abnormalities.
Inhalation: May cause respiratory tract irritation. May cause effects similar to those described
for ingestion. May cause kidney damage.
Chronic: Prolonged or repeated skin contact may cause sensitization dermatitis and possible
destruction and/or ulceration.
Personal Protective Equipment (PPE)
Eyes: Wear appropriate protective eyeglasses or chemical safety goggles as described by
OSHA's eye and face protection regulations in 29 CFR 1910.133
Skin: Viton gloves must be worn while handling picric acid
Clothing: Wear long pants, closed toed shoes and a lab coat
Respirators: Follow the OSHA respirator regulations found in 29 CFR 1910.134 or European
Standard EN 149. Always use a NIOSH approved respirator when necessary.
Engineering Controls: Use process enclosure, local exhaust ventilation, or other
engineering controls to control airborne levels below recommended exposure limits.
First Aid Procedures
Eyes: Flush eyes with plenty of water for at least 15 minutes, occasionally lifting the upper and
lower eyelids. Get medical aid immediately.
Skin: Get medical aid immediately. Flush skin with plenty of water for at least 15 minutes while
removing contaminated clothing and shoes. Wash clothing before reuse.
Ingestion: If victim is conscious and alert, give 2-4 cupfuls of milk or water. Never give anything
by mouth to an unconscious person. Get medical aid immediately.
Inhalation: Remove from exposure and move to fresh air immediately. If not breathing, give
artificial respiration. If breathing is difficult, give oxygen. Get medical aid.
Notes to Physician: Treat symptomatically and supportively.
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Special Handling and Storage Requirements
Handling: Avoid contact with skin and eyes. Avoid formation of dust and aerosols. Provide
appropriate exhaust ventilation at places where dust is formed. Avoid shock and friction. Keep
away from sources of ignition - No smoking.
Storage: Store in a tightly closed container. Store in a cool, dry, well-ventilated area away from
incompatible substances, heat, sparks, flames or other ignition sources.
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Spill and Accident Procedure
Chemical Spill Dial 911 and x59797
Spill – Wear respiratory protection. Avoid dust formation. Avoid breathing dust. Ensure
adequate ventilation. Evacuate personnel to safe areas. Pick up and arrange disposal without
creating dust. Keep in suitable, closed containers for disposal.
Small (<1 L) – If you have training, you may assist in the clean-up effort. Use appropriate
personal protective equipment and clean-up material for chemical spilled. Double bag spill waste
in clear plastic bags, label and take to the next chemical waste pick-up.
Large (>1 L) – Dial 911 (or 310-825-1491 from cell phone) and EH&S at x59797 for
assistance.
Chemical Spill on Body or Clothes – Remove clothing and rinse body thoroughly in
emergency shower for at least 15 minutes. Seek medical attention. Notify supervisor and EH&S
at x59797 immediately.
Chemical Splash Into Eyes – Immediately rinse eyeball and inner surface of eyelid with
water for 15 minutes by forcibly holding the eye open. Seek medical attention. Notify supervisor
and EH&S at x59797 immediately.
Medical Emergency Dial 911 or x52111
Life Threatening Emergency, After Hours, Weekends And Holidays – Dial 911
(or 310-825-1491 from cell phone) or contact the Ronald Reagan UCLA Medical Center
(emergency room) directly at x52111 (located at 757 Westwood Plaza, enter from Gayley
Avenue). Note: All serious injuries must be reported to EH&S at x59797 within 8 hours.
Non-Life Threatening Emergency– Go to the Occupational Health Facility (OHF),
x56771, CHS room 67-120 (This is on the 6th floor, 7th corridor, room 120. Enter through the
School of Dentistry on Tiverton Drive and proceed to the “O” elevator to the 6th floor.)Hours: M F, 7:30 a.m. to 4:30 p.m. At all other times report to Ronald Regan UCLA Medical Center
(emergency room) at x52111. Note: All serious injuries must be reported to EH&S at x59797
within 8 hours.
Needle stick/puncture exposure (as applicable to chemical handling procedure)– Wash
the affected area with antiseptic soap and warm water for 15 minutes. For mucous membrane
exposure, flush the affected area for 15 minutes using an eyewash station. Page the needle stick
nurse by dialing 231 from a campus phone, enter 93333 when prompted and then enter your
extension. Hours: M – F, 8:00 a.m. to 4:00 p.m. At all other times report to Ronald Regan UCLA
Medical Center (emergency room) at x52111. Note: All needle stick/puncture exposures must be
reported to EH&S at x59797 within 8 hours.
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Decontamination/Waste Disposal Procedure
Waste disposal procedures
General hazardous waste disposing guidelines:
Labeling Requirements for Hazardous Waste Containers:
• A UCLA Hazardous Waste Tag must be placed on each hazardous waste container upon
start of accumulation.
• The On-Line Tag Program (OTP) can be used to print hazardous waste tags right from your
printer.
• One account on the On-Line Tag Program (OTP) can be used for the entire lab. See the OnLine Tag Program1 more information and to get your lab signed up.
Hazardous Waste Storage:
• Hazardous waste must be transferred to EH&S for disposal within 90 days of being
generated.
• Waste containers must be in secondary containment at all times to adequately contain the
contents of the container/spilled materials.
• Hazardous waste must always be appropriately labeled with a UCLA waste tag at all times.
• Containers must be closed when not in use.
• Storage of hazardous waste in fume hoods or under sinks is not recommended.
• Hazardous waste that meets the quantity threshold of 55 gallons of hazardous waste or 1
quart of extremely hazardous waste1 must be transferred to EH&S for disposal within 3
days of reaching these set volumes.
• Report damaged containers to EH&S. EH&S can provide assistance to transfer the contents
to an appropriate container.
• Mark storage areas according to the type of chemicals kept there (e.g. “Corrosive”,
“Flammable”, etc.).
• Containers should be inspected weekly for signs of leaks, corrosion, or deterioration.
Hazardous Waste Disposal:
• Don't dispose of chemicals down the drain!
• Don't dispose of chemicals via trashcans.
• Don't use hoods to intentionally evaporate chemicals.
• Transport the hazardous waste to your designated pick-up location using a sturdy cart and
secondary containment.
• Consult the hazardous waste pick-up schedule1 for the building specific times and locations of
disposal.
Material Safety Data Sheet (MSDS) Location
(State the location of MSDS)
Hardcopy or electronic copy must be available.
Online MSDS can be accessed at http://msds.ehs.ucla.edu.
Protocol/Procedure
(Add specific description of procedure.)
Note: Any deviation from this SOP requires written approval from PI.
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Documentation of Training (signature of all users is required)
I have read and understand the content of this SOP:
Name
Signature
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Date