Storage cabinet venting

The use of organic solvents in a clinical laboratory represents a potential fire hazard and hazards to health from inhalation of toxic vapors or skin contact. These solvents should be used m a fume hood. Storage of organic solvents is regulated by rules set down by OSHA (Table 1-16). However, some local fire department rules are more stringent. Solvents should be stored in an OSHA-approved metal storage cabinet that is properly vented. The maximum working volume of flam-... 

NOTE Label safety cans with contents and hazard warning information. Safety cans containing flammable or combustible liquid waste must have appropriate waste labels. Place 20-L (5-gallon) and smaller containers of flammable liquids that are not in safety cans into storage cabinets for flammable liquids. Do not vent these cabinets unless they also contain volatile toxics or odoriferous chemicals. 

If a ventilated flammable-liquid storage cabinet is used under a fume hood, it should not be vented into the fume hood above it. It should have a separate exhaust duct connected to the exhaust system. Fires occur most frequently in fume hoods. Fire from a fume hood may propagate into a flammable-liquid storage cabinet directly vented into the hood. 

For flanomable, volatile, or odorous chemicals, an NFPA-approved flammables storage cabinet should be used. This is typically a yellow metal cabinet fitted with spark-proof ports that can be connected to local exhaust ventilation (see Figure 8.2.1.1). There is no requirement for ventilation but doing so reduces hazards and odors. However, if flammables storage cabinets are vented they must be ducted directly to outdoors. 

No, OSHA does not require you to vent flammable storage cabinets. However, if you choose to vent the cabinets, they must be vented to the outside. 

From this it should be seen that if an aqueous product is stored in a permeable pack, moisture loss will relate to the external environment and whether it is static or is subject to motion or movement. Storage at, say, 37°C 90% RH will be relatively restrictive to moisture loss, whereas 37°C 30% RH will have a significantly greater gradient and losses could be relatively high (particularly if held in a venting cabinet with a fan). 

Because a substantial amount of energy is required to supply tempered supply air to even a small hood, the use of hoods to store bottles of toxic or corrosive chemicals is a very wasteful practice, which can also, as noted above, seriously impair the effectiveness of the hood as a local ventilation device. Thus, it is preferable to provide separate vented cabinets for the storage of toxic or corrosive chemicals. The amount of air exhausted by such cabinets is much less than that exhausted by a properly operating hood. (Also see section 8.C.4.)... 

The system is a floor-standing instrument that includes a vented cabinet for storage of solvents and reagents. Six solvent/reagent reservoirs are available typically for DMF or NMP as a main wash solvent, piperidine-DMF (1 4) for deprotection, DCM as a secondary reagent, HBTU solution for activation, acetic anhydride as a capping solution, and a TFA-based cleavage cocktail. 

If flammable chemicals are stored in base cabinets, in the U.S. the cabinets must comply with National Fire Protection Association (NFPA) Standards 30 and 45 for flammable chemical storage (322,324). Venting, while not required, is also advisable. 

Storage of corrosive chemicals in underhood cabinets requires that the cabinets have corrosion-resistant interiors, louvered doors, and venting into the chamber of the fume hood to draw corrosive vapors out of the cabinet. 

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