Lab Safety - Chemical Hazards
general chem storage
- store compatible substances together - hazardous liquids stored in secondary containment trays/basins/cabinets with built in containment - never store water-reactive chems near sink etc. - don't store hazardous chems above eye level
general chem handling
- use volatiles in chem fume hood - plan and execute work that will minimize hazardous chem exposure - decontaminate and clean work areas when finished with toxic/hazardous stuff
the ____________ lists information about hazards of a substance
Safety Data Sheet (SDS); (ChemWatch is a SDS online database)
cardinal rule of freshman chem lab: add ______ (or ____ ) to water
acid; base
corrosive substances, ________ and ______, quickly damage proteins in body tissue (especially eyes)
acids; bases
general chem disposal
ask PI how to dispose of the chemicals before you start working
peroxide-forming chemicals can _____ ....
build up potentially explosive peroxide on storage and exposure to air and light (check sds)
remove air example
carbon dioxide fire extinguisher, fire blanket of argon or nitrogen
acute toxins
cause damage bc of a single large exposure
use flammables in ____ _____ ______
chemical fume hood
use all volatile toxic materials in a ______ ______ ______
chemical fume hood (or maybe outside if safer)
protect eyes with _____ _______ ______
chemical splash goggles
must wear ______ _____ ______ when handling corrosives, regardless of amount
chemical splash goggles (face shield recommended for larger amounts)
carcinogen
chemical that causes cancer
suspect carcinogen
chemical that probably causes cancer (but not yet proven)
one of the biggest reactivity risks in the lab is _______ ________
chemical waste (so be careful abt waste containers)
teratogens
chemicals that cause birth defects or reproductive harm
mutagens
chemicals that damage DNA
volatile toxic materials
chemicals with appreciable vapor pressure
the recommended shoes:
close-toed, without woven canvas or leather uppers (since spilled chemicals pass thru them)
first layer of PPE is ______
clothes; wear long pants and sleeves and close-toed shoes; restrain loose hair and clothing
Inherent Safety :
concentrates on removing/avoiding hazards rather than controlling them (ex: use less of hazardous chem, or use less extreme conditions for experiment)
wear ______ _____ when handling strong acids/bases
corrosive-resistant gloves
chronic health hazard
covers a broad range of issues, such as sensitizers that, for the rest of your life, will give you a severe allergic reaction when exposed to that chemical
use a _____ ______ if handling reactive, corrosive, or highly toxic substances in large quantities (>500 mL) in a way that may splash
face shield (tho it's not a replacement for goggles--it protects face not eyes
flammable chemicals stored in ________ _________ ______
flammable materials cabinet (law requires this for containers of one gallon or more)
3 things needed to start a fire:
fuel, oxidizing chemical (air, oxygen), source of ignition (spark, static discharge, bunsen burner)
_________ must be resistant to the particular chemicals that will be handled
gloves (each material protects against a certain subset of chemicals in the lab--so wear the right ones)
4 ways to be exposed to hazardous chemicals:
inhalation (lungs aren't good barrier), skin absorption (skin is pretty permeable especially if broken or if chemical is dissolved in solvent), ingestion (gastrointestinal system designed to absorb chemicals soo...), injection
chronic toxins
injures/sickens from long-term, low-level exposures
remove ignition
keep bunsen burners and heat guns out of chemical fume hood when flammables are in use
the ____ _____ is one of the main items of PPE
lab coat; wear at almost all times in lab, tho don't wear it if ur working with machines that could grab clothing; fire-retardant coats are recommended for flammable stuff (coat must cover knees when sitting down)
PPE provides a _________ line of defense against chemical exposure
last
flammable materials cabinet info
no more than 20 gallons of flammables may be outside flammables cabinet in any lab at one time; keep cabinet closed and latched except when actually removing/replacing containers
don't store ______ _______ with anything else
oxidizing acids (e.g., nitric, perchloric, etc.) (bc they can create dangerous by-products if mixed with other sutff)
engineering controls for chemicals:
re-design experiment, working area, or apparatus to avoid/control hazards (ex: use chem fume hood if working with volatile chemicals)
prevent fires by ________ one or more sides of the fire triangle
removing (remove fuel, air, or ignition)
do not use ______ _______ in chemical labs unless ur sure that ur not exposed to splash from hazardous chemicals to eyes
safety glasses (they protect from impact not splash)
for emergencies, call _________
security (at x6,777) - emergency is anything that is still burning/injuring, unconsciousness or burn beyond 2nd degree, exposure to highly toxic/hazardous substance
acids and bases are stored ________
separately (tho it's acceptable to store them in the same corrosives cabinet if they are in separate containment trays)
some corrosives should nt be used by undergrads without _______ ______ and ____________
special training; first-aid supplies
remove fuel example
substituted a flammable solvent for a nonflammable one
4 basic varieties of chemical hazards:
toxic, flammable, corrosive, reactive
PPE for chemcials:
use chem splash goggles for liquid eye hazards, or chemical-resistant gloves to protect from absorption
many different types of chem reactivity:
water-reactives (ex: sodium metal); air-reactives (ex: pyrophoric compounds); peroxide-formers (ex: diethyl or diisopropyl ether)
administrative controls for chemicals:
write detailed experimental protocol, including steps to fix errors (like spills, splashes, etc.)
general chem labeling
- all permanent chemical containers must have a label with the chem name and the principal hazards (name must be full english chem name, no abbreviation) - don't use lick-and-stick labels, don't use a soluble marker (many solvents dissolve sharpie...) - system of pictograms (Globally Harmonized System) appears on chemical bottles to convey principal hazards
first aid for chem exposures:
- inhalation: move victim to location w fresh air - ingestion: call Maryland Poison Center (800-222-1222) for advice, don't induce vomiting unless SDS or poison center says so - skin exposure: flush with lukewarm water for 15 min, remove affected clothing - eye exposure: flush with lukewarm water at eyewash station for 15 min (hold eyes open) - injection: if chem is toxic/corrosive it's emergency, if otherwise, call occupational health services or student health and wellness center or security (if after hours)
for "routine" exposures:
- notify PI and department of health, safety, and environment (HSE) - if emplyed go to occupational health services - go to student health and wellness center if just student - after-hours? go to emergency department at union memorial hospital - always call first to inform nurse on duty always: bring someone along to help, bring SDS for any chemicals u were exposed to, tell the triage nurse that it's a chem exposure from JHU