Facilities

LABORATORY & CHEMICAL HYGIENE PLAN

Corrosive Materials; Flammable Materials; Oxidizers; Moisture Reactive; Compressed Gases; Toxic and Poisonous Substances

Standard Operating Procedure No. 1

Corrosive Materials

Scope: Liquids: Concentrated strong acids, alkali metal hydroxides

Solids:  Non-metallic halides (chlorides, bromides)

Gases:  Halogens and Ammonia

Hazards:   Liquids:  Cause severe and painful burns to human tissue via all exposure routes.  Capable of causing immediate and permanent damage on contact.  Effects exhibited from concentrated acid contact are immediate.  Violent reactions, resulting in the generation of toxic gases and or explosions are capable if acids are mixed with organic solvents or other materials.  Effects exhibited from metal hydroxide contact can be delayed.  Mixing of hydroxides with water generates heat and is very corrosive.

Solids:  Cause severe and painful burns to human tissue via all exposure routes and are acutely toxic.  Non-metallic halides react violently with water, liberating corrosive and toxic gases.  Reaction with acids can explode spontaneously.

Gases:  Halogens such as chlorine, bromine, and iodine are acutely toxic and immediately corrosive upon contact with the skin, eyes, and respiratory system.  They react violently with water and inhalation of fumes can be fatal.  Halogens are extremely strong oxidizers, capable of initiating combustion, sometimes violently, when contacted with a variety of substances.  Ammonia is both acutely toxic and corrosive.

Storage: Liquids:  Store containers when not in use in approved “Corrosive” safety storage cabinets or separate shelving.  If shelving is used, store these materials on lower shelf.  Bases, cyanides, and sulfides, must be separated from acids within the cabinet or shelving unit.  Shelving must have a minimum one-inch lip around the base perimeter.  Purchase glass containers for liquid acids with protective plastic film to minimize spills and splashing if dropped.  Ensure outside of bottles are clean after transfer to prevent corrosion of safety cabinet or shelving unit.  Transfer containers by using a safety bottle carrier when moving from one room to another.  Use rubber stopper for dichromate cleaning solutions to prevent unexpected pressure build-up.

Solids:  Non-metallic halides should be kept tightly sealed when not in use as they react with moisture in the air.

Gases:  Halogens should be stored in a cool, dry place away from direct sunlight.  Halogens must be separated from all other materials and not be stored near any oxidizable or combustible substance.

PPE: Liquids:  Safety Goggles; Rubber Gloves; Instructor Lab-Coat

Solids:  Safety Goggles, Instructor Lab-Coat

Gases:  Safety Goggles; Instructor Lab-Coat

Usage: Liquids:  Concentrated Acids (Hydrochloric, Nitric, Acetic, Hydrofluoric, Sulfuric) and Ammonium Hydroxide must be transferred in the hood.  Recap containers immediately after use.  Ensure leakage from the transfer did not occur on the outside of the container.  When diluting acids, slowly add the acid to the water and not vice versa to prevent violent reaction.  Water should be gently agitated while the acid is slowly added to allow the heat generated to dissipate.  Excessive heat build-up can cause glass containers to rupture.  When making dilute base solutions, follow the same procedure, by slowly adding the desired amount of base material to gently agitated water.

Solids:  Non-metallic halides must be worked with inside of hood.  Care must be exercised to avoid the introduction of water.

Gases:  Halogen gases and ammonia are supplied in gas cylinders.  Cylinders must be well secured during experimentation.  All experiments must be done in hood.  Valves must be opened slowly to prevent rupture or detachment of cylinder tubing and subsequent vapor release.

Waste: Liquids, Solids, Gases:  Contact Maine Department of Environmental Protection for details.  Wastes may be hazardous in nature requiring disposal by a DEP-licensed contractor.  


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