Definition/ Indicators

—The hazardous substance has been identified or is an unknown, and requires the highest level of protection for skin, eyes, and the respiratory system based on either the measured (or potential for) high concentration of atmospheric vapors, gases, or particulates; or the site operations and work functions involve a high potential for splash, immersion, or exposure to unexpected vapors, gases, or particulates of materials that are harmful to skin or capable of being absorbed through the skin.

—Substances with a high degree of hazard to the skin are known or suspected to be present, and skin contact is possible; or

—Operations must be conducted in confined, poorly ventilated areas, and the absence of conditions requiring Level A have not yet been determined.

—When an event is uncontrolled or information is unknown about: the type of airborne agent, the dissemination method, if dissemination is still occurring or it has stopped.

—The type and atmospheric concentration of substances have been identified and require a high level of respiratory protection, but less skin protection.

—The atmosphere contains less than 19.5 percent oxygen; or

—The presence of incompletely identified vapors or gases is indicated by a direct-reading organic vapor detection instrument, but vapors and gases are not suspected of containing high levels of chemicals harmful to skin or capable of being absorbed through the skin.

—A liquid-splash-resistant ensemble used with the highest level of reparatory protection.

—The suspected aerosol is not longer being generated, but other conditions may present a splash hazard.

—The atmospheric contaminants, liquid splashes, or other direct contact may adversely affect or be absorbed through any exposed skin.

—The types of air contaminants have been identified, concentrations measured, and an air-purifying respirator is available that can remove the contaminants; and

—All criteria for the use of air-purifying respirators are met.

—Selected when the atmosphere contains no known hazards.

Work functions preclude splashes, immersion, or the potential for unexpected inhalation of or contact with hazardous levels of any chemicals.

Ensemble/ Component

—A fully encapsulated, liquid and vapor protective ensemble selected when the highest level of skin, reparatory and eye protection is required.

—Positive pressure, full face-piece self-contained breathing apparatus (SCBA), or positive pressure supplied air respirator with escape SCBA, approved by the National Institute for Occupational Safety and Health (NIOSH).  Closed-circuit Rebreather/ open circuit SCBA.

—Totally-encapsulating chemical-protective suit.

—Gloves, outer, chemical-resistant.

—Gloves, inner, chemical-resistant.

—Boots, chemical-resistant, steel toe and shank, outer booties.

—Disposable protective suit, gloves and boots (depending on suit construction, may be worn over totally-encapsulating suit).

—Coveralls.*

—Long underwear.*

—Hard hat (under suit), personal cooling system, chemical resistant tape.*

*Optional/as needed.

—A liquid-splash-resistant ensemble used with the highest level of reparatory protection.

—Positive pressure, full-face piece self-contained breathing apparatus (SCBA), or positive pressure supplied air respirator with escape SCBA (NIOSH approved).

—Hooded chemical-resistant clothing (overalls and long-sleeved jacket; coveralls; one or two-piece chemical-splash suit; disposable chemical-resistant overalls).

—Gloves, outer, chemical-resistant.

—Gloves, inner, chemical-resistant.

—Boots, outer, chemical-resistant steel toe and shank.

—Boot-covers, outer, chemical-resistant.

—Hard hat, personal cooling system, chemical resistant tape.*

—Coveralls.*

—Face shield.*

*Optional/as needed.

—A liquid-splash-resistant ensemble, with the same level of skin protection as Level B, used when the concentration(s) and type(s) of airborne substances(s) are known and the criteria for using air-purifying respirators are met.

—Full-face or half-mask, air purifying respirators (NIOSH approved).

—Hooded chemical-resistant clothing (overalls; two-piece chemical-splash suit; disposable chemical-resistant overalls).

—Gloves, outer, chemical-resistant.

—Gloves, inner, chemical-resistant.

—Boots (outer), chemical-resistant steel toe and shank.

—Boot-covers, outer, chemical-resistant.

—Coveralls.*

—Hard hat, face shield, personal cooling system.*

—Escape mask.*

—Face shield.*

*Optional/as needed.

—A work uniform affording minimal protection: used for nuisance contamination only.

—Coveralls.

—Boots/shoes, chemical-resistant steel toe and shank.

—Boots, outer, chemical-resistant (disposable).*

—Gloves.*

—Safety glasses or chemical splash goggles.*

—Hard hat.*

—Escape mask.*

—Face shield.*

*Optional/as needed.

Definition/ Indicators

—The hazardous substance has been identified or is unknown,  and requires the highest level of protection for skin, eyes, and the respiratory system based on either the measured (or potential for) high concentration of atmospheric vapors, gases, or particulates; or the site operations and work functions involve a high potential for splash, immersion, or exposure to unexpected vapors, gases, or particulates of materials that are harmful to skin or capable of being absorbed through the skin.

—Substances with a high degree of hazard to the skin are known or suspected to be present, and skin contact is possible.

—Operations must be conducted in confined, poorly ventilated areas, and the absence of conditions requiring Level A have not yet been determined.

—When an event is uncontrolled or information is unknown about: the type of airborne agent, the dissemination method, if dissemination is still occurring or it has stopped.

—The type and atmospheric concentration of substances have been identified and require a high level of respiratory protection, but less skin protection.

—The atmosphere contains less than 19.5 percent oxygen; or

—The presence of incompletely identified vapors or gases is indicated by a direct-reading organic vapor detection instrument, but vapors and gases are not suspected of containing high levels of chemicals harmful to skin or capable of being absorbed through the skin.

—Necessary to provide sufficient vapor protection for the intended operation, where direct contact of liquid droplets is probable, and where victims are not ambulatory but symptomatic.

—The agent or threat has generally been identified and where the actual release has subsided.  Exposure include possible contact with residual vapor or gas and highly contaminated surfaces.

—The atmospheric contaminants, liquid splashes, or other direct contact may adversely affect or be absorbed through any exposed skin.

—The types of air contaminants have been identified, concentrations measured, and an air-purifying respirator is available that can remove the contaminants; and

—All criteria for the use of air-purifying respirators are met.

—Use well after the release has occurred or in the peripheral zone of the release scene.  Or when there is no potential for vapor or gas exposure and exposure to liquids is expected to be incidental through contact with contaminated surfaces.

—Necessary to provide sufficient liquid protection for the intended operation, where direct contact of liquid droplets is possible, and where victims are impaired but ambulatory.

—Selected when the atmosphere contains no known hazards.

—Work functions preclude splashes, immersion, or the potential for unexpected inhalation of or contact with hazardous levels of any chemicals.

Ensemble/ Component

—A fully encapsulated, liquid and vapor protective ensemble selected when the highest level of skin, reparatory and eye protection is required.

—Positive pressure, full face-piece self-contained breathing apparatus (SCBA), or positive pressure supplied air respirator with escape SCBA, approved by the National Institute for Occupational Safety and Health (NIOSH).  Gas tight.

—Totally-encapsulating chemical-protective suit.  Highest levels of permeation resistance. Highest level of physical hazard resistance.

—Disposable protective suit, gloves and boots (depending on suit construction, may be worn over totally-encapsulating suit).

—Gloves, outer, chemical-resistant.

—Gloves, inner, chemical-resistant.

—Boots, chemical-resistant, steel toe and shank.

—Coveralls.*

—Long underwear.*

—Hard hat (under suit).*

*Optional/as needed.

—A liquid-splash-resistant ensemble used with the highest level of reparatory protection.

—Positive pressure, full-facepiece self-contained breathing apparatus (SCBA), or positive pressure supplied air respirator with escape SCBA (NIOSH approved). Not gas tight, but still low levels of leakage (< 2%).

—Hooded chemical-resistant clothing (overalls and long-sleeved jacket; coveralls; one or two-piece chemical-splash suit; disposable chemical-resistant overalls).  Permeation resistance and shower test to show no penetration of liquid.

—Gloves, outer, chemical-resistant. Lower levels of physical hazard resistance.

—Gloves, inner, chemical-resistant.

—Boots, outer, chemical-resistant steel toe and shank.

—Boot-covers, outer, chemical-resistant.*

—Coveralls.*

—Hard hat.*

—Face shield.*

*Optional/as needed.

—A liquid-splash-resistant ensemble, with the same level of skin protection as Level B, used when the concentration(s) and type(s) of airborne substances(s) are known and the criteria for using air-purifying respirators are met.

—Full-face or half-mask, air purifying respirators (NIOSH approved).  Not gas tight.

—Hooded chemical-resistant clothing (overalls; two-piece chemical-splash suit; disposable chemical-resistant overalls).  Must be liquid tight, not tested on gases.

—Gloves, outer, chemical-resistant.

—Gloves, inner, chemical-resistant.

—Coveralls*7.

—Boots (outer), chemical-resistant steel toe and shank.*

—Boot-covers, outer, chemical-resistant (disposable).*

—Hard hat.*

—Escape mask.*

—Face shield.*

*Optional/as needed.

—A work uniform affording minimal protection: used for nuisance contamination only.

—Coveralls.

—Boots/shoes, chemical-resistant steel toe and shank.

—Boots, outer, chemical-resistant (disposable).*

—Gloves.*

—Safety glasses or chemical splash goggles.*

—Hard hat.*

—Escape mask.*

—Face shield.*

*Optional/non-mandatory.

Definition/ Indicators

—The hazardous substance has been identified or is unknown, and requires the highest level of protection for skin, eyes, and the respiratory system based on either the measured (or potential for) high concentration of atmospheric vapors, gases, or particulates; or the site operations and work functions involve a high potential for splash, immersion, or exposure to unexpected vapors, gases, or particulates of materials that are harmful to skin or capable of being absorbed through the skin.

—Substances with a high degree of hazard to the skin are known or suspected to be present, and skin contact is possible.

—Operations must be conducted in confined, poorly ventilated areas, and the absence of conditions requiring Level A have not yet been determined.

—When an event is uncontrolled or information is unknown about: the type of airborne agent, the dissemination method, if dissemination is still occurring or it has stopped.

—The type and atmospheric concentration of substances have been identified and require a high level of respiratory protection, but less skin protection.

—The atmosphere contains less than 19.5 percent oxygen: or

—The presence of incompletely identified vapors or gases is indicated by a direct-reading organic vapor detection instrument, but vapors and gases are not suspected of containing high levels of chemicals harmful to skin or capable of being absorbed through the skin.

—The atmospheric contaminants, liquid splashes, or other direct contact may adversely affect or be absorbed through any exposed skin.

—The types of air contaminants have been identified, concentrations measured, and an air-purifying respirator is available that can remove the contaminants; and

—All criteria for the use of air-purifying respirators are met.

—Selected when the atmosphere contains no known hazards.

—Work functions preclude splashes, immersion, or the potential for unexpected inhalation of or contact with hazardous levels of any chemicals.

Ensemble/ Component

—A fully encapsulated, liquid and vapor protective ensemble selected when the highest level of skin, reparatory and eye protection is required (level A).

—Closed circuit rebreather or open circuit Self-Contained Breathing Apparatus (SCBA) or, when appropriate, Supplied Air Breathing Apparatus (SABA) (level A).

—Reusable or limited-use fully encapsulated chemical resistant suit ensemble (level A).

—Chemical Resistant Gloves, including thermal as appropriate to hazard (level A).

—Chemical resistant boots, steel or fiberglass toe and shank (level A).

—Chemical Resistant Outer Booties (level A).

—Disposable protective suit, gloves and boots (depending on suit construction, may be worn over totally-encapsulating suit).

—Two-Way Local In-suit Communications.

—Personnel Accountability System to alert for downed personnel (specific to SCBA use only).

—A liquid-splash-resistant ensemble used with the highest level of reparatory protection (level B).

—Closed circuit rebreather or open circuit SCBA or, when appropriate, SABA (level B).

—Hooded chemical-resistant clothing (overalls and long-sleeved jacket; coveralls; one or two-piece chemical-splash suit; disposable chemical-resistant overalls).

—Liquid Chemical Splash Resistant Hood (permeable or non-permeable) (level B).

—Chemical Resistant Gloves, including thermal as appropriate to hazard (level B).

—Chemical resistant boots, steel or fiberglass toe and shank (level B).

—Chemical Resistant Outer Booties (level B).

—Spare cylinders for rebreathers, SCBA or SABA, and service/repair kits.

—HAZMAT gear bag.

—A liquid-splash-resistant ensemble, with the same level of skin protection as Level B, used when the concentration(s) and type(s) of airborne substances(s) are known and the criteria for using air-purifying respirators are met (level C).

—Full-Face Air Purifying Respirators with appropriate cartridges or positive pressure units (Powered Air Purifying—PAPR) (level C).

—Liquid Chemical Splash Resistant Hood (permeable or non-permeable) (level C).

—Hooded chemical-resistant clothing (overalls; two-piece chemical-splash suit; disposable chemical-resistant overalls) (level C).

—Chemical Resistant Gloves, including thermal as appropriate to hazard (level C).

—Chemical resistant boots, steel or fiberglass toe and shank (level C).

—Chemical Resistant Outer Booties (level C).

—HAZMAT gear bag.

—Emergency Escape Breathing Apparatus (EEBA) 10 minutes or longer.

—A work uniform affording minimal protection: used for nuisance contamination only (level D).

—Escape mask for self-rescue.

—Decontamination Equipment used to clean, remediate, remove, or mitigate chemical or biological contamination of first responders.

Definition/ Indicators

—The hazardous substance has been identified or is unknown, and requires the highest level of protection for skin, eyes, and the respiratory system based on either the measured (or potential for) high concentration of atmospheric vapors, gases, or particulates; or the site operations and work functions involve a high potential for splash, immersion, or exposure to unexpected vapors, gases, or particulates of materials that are harmful to skin or capable of being absorbed through the skin.

—Substances with a high degree of hazard to the skin are known or suspected to be present, and skin contact is possible.

—Operations must be conducted in confined, poorly ventilated areas, and the absence of conditions requiring Level A have not yet been determined.

—When an event is uncontrolled or information is unknown about: the type of airborne agent, the dissemination method, if dissemination is still occurring or it has stopped.

—The type and atmospheric concentration of substances have been identified and require a high level of respiratory protection, but less skin protection.

—The atmosphere contains less than 19.5 percent oxygen; or

—The presence of incompletely identified vapors or gases is indicated by a direct-reading organic vapor detection instrument, but vapors and gases are not suspected of containing high levels of chemicals harmful to skin or capable of being absorbed through the skin.

—Full respiratory protection is required but danger to the skin from vapor is less.  It differs from Level A that is incorporates a non-encapsulating, splash-protective, chemical-resistant suit (splash suit) that provides Level A protection against liquids, but is not airtight.

—The atmospheric contaminants, liquid splashes, or other direct contact may adversely affect or be absorbed through any exposed skin.

—The types of air contaminants have been identified, concentrations measured, and an air-purifying respirator is available that can remove the contaminants; and

—All criteria for the use of air-purifying respirators are met.

—Utilizes a splash suit along with a full-faced positive—negative pressure respirator (a filter-type gas mask) rather than a SCBA or air line.

—Selected when the atmosphere contains no known hazards.

—Work functions preclude splashes, immersion, or the potential for unexpected inhalation of or contact with hazardous levels of any chemicals.

Ensemble/ Component

—A fully encapsulated, liquid and vapor protective ensemble selected when the highest level of skin, reparatory and eye protection is required.

—Positive pressure, full face-piece self-contained breathing apparatus (SCBA), or positive pressure supplied air respirator with escape SCBA, approved by the National Institute for Occupational Safety and Health (NIOSH).  Pressure-demand, self-contained breathing apparatus (SCBA) or pressure-demand supplied respirator (air hose) and escape SCBA.

—Totally-encapsulating chemical-protective suit.

—Gloves, outer, chemical-resistant.

—Gloves, inner, chemical-resistant.

—Boots, chemical-resistant, steel toe and shank.

—A liquid-splash-resistant ensemble used with the highest level of reparatory protection.

—Positive pressure, full-facepiece self-contained breathing apparatus (SCBA), or positive pressure supplied air respirator with escape SCBA (NIOSH approved).

—Hooded chemical-resistant clothing (overalls and long-sleeved jacket; coveralls; one or two-piece chemical-splash suit; disposable chemical-resistant overalls).

—Gloves, outer, chemical-resistant.

—Gloves, inner, chemical-resistant.

—Boots, outer, chemical-resistant steel toe and shank.

—Boot-covers, outer, chemical-resistant (disposable).

—A liquid-splash-resistant ensemble, with the same level of skin protection as Level B, used when the concentration(s) and type(s) of airborne substances(s) are known and the criteria for using air-purifying respirators are met.

—Full-face or half-mask, air purifying respirators (NIOSH approved).

—Hooded chemical-resistant clothing (overalls; two-piece chemical-splash suit; disposable chemical-resistant overalls).

—Gloves, outer, chemical-resistant.

—Gloves, inner, chemical-resistant.

—Boots (outer), chemical-resistant steel toe and shank.

—Boot-covers, outer, chemical-resistant (disposable).

—A work uniform affording minimal protection: used for nuisance contamination only.

—Coveralls.

—Gloves.

—Boots/shoes, chemical-resistant steel toe and shank.

—Safety glasses or chemical splash goggles.

—Hard hat.

—Escape mask.