operating procedures (SOP) are intended to provide you with general guidance on
how to safely work with a specific class of chemical or hazard. This SOP is
generic in nature. It addresses the use and handling of substances by hazard
class only. In some instances multiple SOPs may be applicable for a specific
chemical (i.e., both the SOPs for flammable liquids and carcinogens would apply
to benzene). If you have questions concerning the applicability of any item
listed in this procedure contact the EHRS 215-898-4453 or the Principal
Investigator of your laboratory. Specific written procedures are the
responsibility of the Principal Investigator.
compliance with all the requirements of this standard operating procedure is
not possible, the Principal Investigator must develop a written procedure that
will be used in its place. This alternate procedure must provide the same level
of protection as the SOP it replaces. The Office of Environmental Health and
Radiation Safety is available to provide guidance during the development of
Corrosive chemicals are substances that
cause visible destruction or permanent changes in human skin tissue at the site
of contact, or are highly corrosive to steel. Corrosive chemicals can be
liquids, solids, or gases and can affect the eyes, skin, and respiratory tract. The major classes of corrosives include
strong acids, bases, and dehydrating agents.
Liquid corrosive chemicals are those with a pH of 4.0
or lower or a pH of 9 or higher. Solid chemicals are considered corrosive when
in solution; they fall in the above pH range. A highly corrosive chemical has a pH of 2 or lower or a
pH of 12.5 or higher. Injurious
chemicals cause tissue destruction at the site of contact.
Some examples of corrosive
Strong Acids: hydrochloric, sulfuric, phosphoric
Strong Bases: hydroxides of sodium, potassium, ammonia
Corrosives: sulfuric, phosphophrous
pentoxide, calcium oxide
Corrosives: concentrated hydrogen
peroxide, sodium hypochlorite
Corrosive Gases: chlorine, ammonia
Solids: phosphorous, phenol
TO SECTION IN THIS S.O.P.
- Most corrosives
can be used by properly-trained individuals in the laboratory environment
without the need for specific EHRS approval.
Special circumstances, such as abnormally large-scale use may require
evaluation. Contact EHRS at x84453 for
should be notified before purchasing hydrofluoric acid for use in your
laboratory for the first time. See the HF Safety Fact sheet for more details about working with liquid hydrofluoric acid.
should be notified before purchasing certain corrosive compressed gases such as
- Training requirements based on job
duties and responsibilities are determined for each employee by completing the Penn
- Any corrosives
users should have taken an Introduction to Laboratory Safety course as well as
any required annual updates.
- Most introductory programs are offered
monthly. Dates are published in the Almanac
and on the
EHRS website. Annual updates of these programs
completed online. For more information on these
programs or to request a training program on safety or health topics for your
department, please contact Valerie
Perez at 215-746-6652
or send email to: email@example.com
of any container of corrosives with a volume of greater than 5 gallons for
laboratory use requires EHRS approval.
- A hazard
assessment for work involving corrosives must thoroughly address the issues of
proper use and handling, fire safety, chemical toxicity, storage, and spill
- A hazard
assessment must be conducted when a process/reaction/work-up/or purification is
changed or when scaling-up any corrosives use to more than 10 times the
- The first
time a highly hazardous corrosive material such as concentrated sulfuric or
nitric acid is used for a process, a hazard assessment should be conducted.
request EHRS can assist you in performing a thorough hazard assessment.
Corrosive Chemical Storage Cabinets
should be segregated according to the Chemical Storage and Transportation section of the Chemical Hygiene Plan
- Cabinets: Specially designed corrosion resistant
cabinets should be used for the storage of large quantities of corrosive
materials. For new lab construction, renovations, and whenever possible in
existing labs, the specifications for acid cabinets found in the Laboratory
Design & Equipment section of the EHRS website
should be followed. Cabinets for storing
alkaline corrosive materials should be of the same construction whenever
- If no corrosion-resistant cabinet is
available, store corrosives on plastic trays.
- Do not store corrosive liquids above
- Engineering Controls
(ventilation, shielding, vacuum protection)
- Safety Shielding: Shielding is required any time there is a
risk of explosion, splash hazard or a highly exothermic reaction. All manipulations of corrosives which pose
this risk should occur in a fume hood with the sash in the lowest feasible
position. Portable shields, which
provide protection to all laboratory occupants, are also acceptable.
- Special Ventilation:
Corrosive materials must be handled in a chemical
fumehood if production of corrosive vapor is anticipated. Manipulation of corrosives outside of a fume
hood may require special ventilation controls in order to minimize exposure to
the material. Fume hoods provide the best protection against exposure to corrosives
in the laboratory and are the preferred ventilation control device. Always attempt
to handle quantities of corrosives greater than 500 mL in a fume hood. If your
research does not permit the handing of large quantities of corrosives in your
fume hood, contact the EHRS to review the adequacy of all special ventilation.
- Vacuum Protection:
Evacuated glassware can implode and eject
flying glass, and chemicals. Vacuum work involving corrosives must be conducted
in a fume hood, glove box or isolated in an acceptable manner. Mechanical vacuum pumps must be protected
using cold traps and, where appropriate, filtered to prevent particulate
release. The exhaust for the pumps must be vented into an exhaust hood. Vacuum
pumps should be rated for use with corrosives.
- Personal Protective Equipment
- Splash proof goggles in addition to
standard laboratory personal protective equipment (PPE)
consisting of a 100% cotton lab coat, closed toe shoes and nitrile gloves must
be worn when there is a significant risk of splash. Pouring very large volumes or handling
particularly corrosive materials may require additional PPE
consisting of thicker gloves and an apron. Contact EHRS with assistance in
selecting chemical resistant personal protective equipment that is appropriate
for the materials you are handling and the type of work you are doing.
- Eye protection in the form of safety
glasses must be worn at all times when handling corrosives. Ordinary (street)
prescription glasses do not provide adequate protection. (Contrary to popular
opinion these glasses cannot pass the rigorous test for industrial safety
glasses.) Adequate safety glasses must meet the requirements of the Practice
for Occupational and Educational Eye and Face Protection (ANSI Z.87. 1 1989)
and must be equipped with side shields. Safety glasses with side shields do not
provide adequate protection from splashes; therefore, when the potential for a splash
hazard exists other eye protection and/or face protection must be worn. In addition to safety glasses, a face shield
should be worn when splash or spray is foreseeable.
- Gloves must be worn when handling corrosives. Disposable nitrile gloves (4 mil minimum
thickness) provide adequate protection against accidental hand contact with
small quantities of most laboratory chemicals.
Lab workers should contact EHRS for advice on chemical resistant glove
selection when direct or prolonged contact with hazardous chemicals is anticipated.
- Some examples of when specialty gloves
may be necessary are: Handling of
hydrofluoric acid, when immersion in corrosive liquids is anticipated, when
large volumes of corrosive liquids are being transferred or dispensed.
- At a minimum, 100% cotton lab coats,
closed toed shoes and long-sleeved clothing must be worn when handling corrosives. Additional protective clothing, such as a
chemical-resistant apron, should be worn if the possibility of skin contact is
- Protect all skin surfaces from contact
with corrosive or irritating gases and vapors.
- Emergency Irrigation (Eyewash and
- A safety or drench shower should be
available within 10 seconds of travel from where the corrosives are used.
- Safety showers are tested annually by facility’s
- Where the eyes or body of any person
may be exposed to corrosives, suitable facilities for quick drenching or
flushing of the eyes and body shall be provided within the work area for
immediate emergency use. Bottle type
eyewash stations are not acceptable.
- Eyewashes must be activated weekly by
laboratory workers to ensure proper function of equipment and to flush the
Carrying out your work
Consult the Material Safety Data Sheet (MSDS) for
any new corrosive chemicals you introduce to your lab. Fully assess the potential hazards and
consider what safety equipment will be needed before you begin your work. EHRS can provide you with an MSDS for any
chemical you plan to use.
process for liquids should be designed to minimize the potential for splash,
splatter, or other likely scenarios for accidental contact.
- Do not
pour water into acid. Slowly add acid to
water with stirring and cooling if heat generation can be anticipated.
involving acids and bases are often very exothermic
- Use only heat resistant labware
- Allow for extra volume in your mixing or reaction
vessel to account for expansion and/or foaming
- It may be necessary to pre-cool solutions and
cool while mixing or reacting
- Corrosive Gases
compressed gases can burn and destroy body tissue (especially the eyes or
respiratory contact) on contact. The
magnitude of the effect is related to the solubility of the material in the
body fluids. Highly soluble gases such
as ammonia or hydrogen chloride can cause severe nose and throat irritation,
while substances of lower solubility such as nitrogen dioxide, phosgene, or
sulfur dioxide can penetrate deep into the lungs. Corrosive gases also can corrode metals. Warming properties such as odor or eye, nose
or respiratory tract irritation may be inadequate with some substances. Do not rely upon these symptoms as warning of
procedures detailed in the Compressed Gases Standard Operating Procedure should be followed for work with corrosive
manipulations of materials that pose an
inhalation hazard in a chemical fume hood to control exposure.
prevent environmental pollution and damage to equipment it may be necessary to
trap and or scrub exhaust from processes which utilize corrosive gases even
when working in the fume hood. Contact
EHRS for assistance with design and set-up of gas neutralization processes.
corrosive gases are to be discharged into a liquid, a trap, check valve, or
vacuum break device must be employed to prevent dangerous reverse flow.
and valves must be closed when the cylinder is not in use and flushed with dry
air or nitrogen after use.
- All corrosives
must be clearly labeled with the correct chemical name. Handwritten labels are acceptable; chemical
formulas and structural formulas are not acceptable.
- The label
on any containers of corrosives should say “Flammable” and include any other
hazard information, such as “Flammable” or “Toxic”, as applicable.
- Heating/Open flame
- Do not
store corrosives in chemical fume hoods or allow containers of corrosives in
proximity to heating mantles, hot plates, or torches.
transferring, and dispensing of corrosive solids must be performed carefully to
avoid aspiration and ingestion of airborne powders and solids.
materials of construction for lab apparatus and vessels that will come in
contact with corrosive chemicals must be evaluated for compatibility with the
chemical in use.
corrosives in secondary containment, preferably a polyethylene or other
non-reactive bottle carrier and/or a sturdy cart designed for chemical
combining acid and water, always add ACID to WATER
- Small spills
- Anticipate spills by having the
appropriate clean up equipment on hand. The appropriate clean up supplies can
be determined by consulting the material safety data sheet. This should occur
prior to the use of any corrosives.
- Corrosive spill controls neutralize the
hazardous nature of the spilled material. Acids and bases require different
types of spill control materials.
acid and base neutralizing spill kits are available from Fisher Scientific.
carbonate (soda ash) can also be used to neutralize spills of acidic liquids
prior to clean-up. Do not attempt to
neutralize a hydrofluoric acid spill.
EHRS should be notified to handle all spills involving hydrofluoric
the event of a spill all personnel in the area should be alerted. Turn off all
sources of ignition.
- Waste disposal
are hazardous wastes. Questions
regarding waste disposal should be directed to the EHRS.
caps for 1-gallon sized plastic containers are available from EHRS for
collection of wastes that are likely to produce gas. These wastes include mixtures of corrosive
liquids and peroxides (such as Piranha and Chromerge).
- Personnel: Immediately flush contaminated area with copious amounts of water
after contact with corrosive materials. Remove any jewelry to facilitate
removal of chemicals. If a delayed response is noted report immediately for
medical attention. Be prepared to detail what chemicals were involved.
- If the incident involves hydrofluoric acid (HF), seek
immediate medical attention.
- If there is any doubt about the severity of the injury, seek
immediate medical attention.
- Area: Decontamination procedures vary
depending on the material being handled.
Contact EHRS in the event of a large spill.
- Large spills
- Do not attempt to handle a large spill
of corrosives. Vacate the laboratory immediately and call for assistance.
- Office of
Environmental Health & Radiation Safety, 215-898-4453
- University Police 511
or 215-573-3333. This is a 24 hour service.
on the scene, but at a safe distance, to receive and direct safety personnel
when they arrive.
- Pull the
- Turn out
the lights and close your laboratory door when everyone is out
- Call 511
from a university phone or 215-573-3333 from a safe location to
give Penn Police more information about the fire situation
yourself available to give emergency responders information as needed