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Haz-Ops

Date post: 01-Jan-2016
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Haz-Ops. Operations vs Awareness. Awareness is the lowest level of training allowed by the NFPA. It allows for recognition of containers and contents in hazardous situations. Operations level of training allows for defensive actions of responders to hazardous material situations. PPE. - PowerPoint PPT Presentation
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Haz-Ops
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Haz-Ops

Operations vs Awareness

• Awareness is the lowest level of training allowed by the NFPA. It allows for recognition of containers and contents in hazardous situations.

• Operations level of training allows for defensive actions of responders to hazardous material situations.

PPE

• Four LevelsA – fully capsulated with SCBA

B – splash guard with SCBA or SAR

C – splash guard with air-purifying respirator

D – normal duty wear

Level A

• Highest level of protection

• Must be trained in it’s use

• Meets NFPA 1991• Can be cumbersome

to work in

Level B

• Same respiratory protection but less protection to the skin

• Meets NFPA 1992• Easier to move in, but

there must be no known chemical danger to the skin

Level C

• Same skin protection as Level B with lower respiratory protection

• Substance must be known

• Use only with IC’s OK

Level D

• No significant protection

• Use only for nuisance calls

Respiratory Protection

• SCBA• Must meet NFPA

1981• Portable,

manueverable, heavy• SAR• Not fire approved• Limited distance,

lighter than SCBA

Respiratory

• APR – Air-purifying respirator

• Limited use• Easy to use• Filters for particles

and gas/vapors

Climate Concerns

• Heat rash – develops from constant exposure to heat and humid air

• Heat cramps – long exposure to heat with fluid loss – leg/abdominal cramps, faintness, dizziness

Climate Concerns

• Heat exhaustion – exposure to excessive heat. Symptoms are weakness, cool/clammy skin, heavy perspiration, rapid/shallow breathing, weak pulse, possible unconsciousness

Climate Concerns

• Heat Stroke – Caused by heat exposure resulting in failure of the body’s heat regulating system.

• Symptoms include high fever (105 to 106), dry, hot, red skin, rapid, strong pulse, deep breaths and possible convulsions. Can result in coma or death

Prevention

• Hydrate before beginning operations. It is better to drink 200 ml every 15 to 20 minutes than a large quantity once an hour.

• Wear long cotton undergarments for natural ventilation

• Work in rotation and rehab

Medical Monitoring

• Complete vitals must be taken prior to entering and after exiting the hot or warm operating zones.

Working Hazards

• Thermal

• Radiological

• Asphyxiation

• Chemical

• Etiological/Biological

• Mechanical

Thermal

• Extreme temperatures

• Exothermic reactions

• Cryogenic Liquids

Radiological

• Alpha – small, goes short distance

• Beta – Fast-moving, travels up to 20’

• Gamma – High energy, travels great distances

Radiation

• Three methods of protection

– Time

– Distance – doubling the distance reduces the exposure by 4 times. Halving the distance increases it by 4 times

– Shielding

Shielding

Asphyxiation

• Simple asphyxiants displace oxygen

• Chemical asphyxiants prohibit the body from using oxygen

Chemical

• Toxicity of the chemical

• Pathway or route of exposure

• Nature and extent of exposure

Routes of Entry

• Inhalation

• Ingestion

• Contact

• Absorbtion

Etiological/Biological

• Microorganisms such as viruses or bacteria (or their toxins) that may cause severe, disabling disease or illness

Mechanical

• Can cause trauma that occurs as a result of direct contact with an object.

• Striking and friction are the two most common types

Hazard Properties

• Physical state

– Gas – expands indefinitely – no shape

– Liquid – specific volume that flows according to gravity – no shape

– Solid – has shape and volume

Terms

• Vapor pressure – the pressure exerted or produced by the vapors released from a liquid. A measure of the tendency of a substance to evaporate

• Boiling point – Temperature at which the vapor pressure is equal to or greater than atmospheric pressure.

Terms

• Vapor density – weight of a given volume of pure vapor or gas compared to the weight of an equal volume of dry air at the same temp. A vapor density of less than 1 is lighter than air

• Solubility – percentage of a material (by weight) that will dissolve in water at ambient temperature.

Hydrocarbon vs polar solvent

• Hydrocarbons such as gasoline, diesel fuel are non-soluble and will not mix with water

• Polar solvents such as alcohol, methanol mix readily in water

More Terms

• Miscibility is the degree to which two or more gases or liquids are able to mix with or dissolve into each other

• Specific Gravity is the ratio of the density (heaviness) of a material to the density of some standard material as standard conditions of pressure and temperature

Specific Gravity

• If a volume of a material weighs 8 pounds and the same volume of water weighs 10 pounds, the specific gravity of the material is 0.8

• Specific gravity of less than 1 will float on water. Most hydrocarbons, like gasoline, have a specific gravity of less than one

More Terms

• Persistence is the ability of the chemical to remain in the environment

• Reactivity is a substances relative ability to undergo a chemical reaction with another material

The Path of a Hazardous Release

• Stress. When a container is stressed beyond it’s design strength, it fails, or breaches

The Path of a Hazardous Release

• Breach. The way a container breaches is based on the material of which it is constructed, the type of stress it was exposed to, and the pressure inside the container at the time it fails.

Type of Breaching

• Disintegration – Container suffers a general loss of integrity - like a grenade blowing up

• Runaway cracking – A crack develops in a container as a result of some type of damage, which continues to grow rapidly, breaking the container into two or more relatively large pieces

Type of Breaching

• Attachments (closures) open or break – attachments such as pressure relief valves, discharge valves, etc. fail, open or break off. This usually leads to total failure of the container

• Puncture – Mechanical stress coming into contact with the container

Type of Breaching

• Split or tear – seams fail or tear. Mechanical or thermal stressors may cause splits

The Path of a Hazardous Release

• Release. When a container is breached or fails, its contents, stored energy, and pieces of the container may release

• There are four ways in which containers release their content

Four Releases

• Detonation – Instantaneous and explosive release of stored chemical energy of a hazardous material

• Violent rupture – Immediate release of chemical or mechanical energy caused by runaway cracks

Four Releases

• Rapid Relief – Fast release of a pressurized hazardous material through properly operating safety devices

• Spill/Leak – Slow release of hazardous material under atmospheric or head pressure through holes, tears, rips or usual openings/attachments

The Path of a Hazardous Release

• Dispersion/Engulf. When released the product inside the container, any stored energy and the container disperse. How and where they go are based in chemistry, physics, and product characteristics

Dispersion

• Hemispheric – Dome-shaped pattern of airborne product that is still in contact with the ground or water

• Cloud – Ball-shaped pattern of airborne material that has collectively risen above the ground or water

Dispersion

• Plume - Irregular shaped pattern of airborne product. Many factors influence a plume including wind, terrain, product characteristics. Etc

• Cone – Triangular shaped pattern with a point at the source of the breach and a wide base downrange

Dispersion

• Stream – Surface following pattern of a liquid material that is affected by gravity and topographical contours

• Pool – Three dimensional (including depth), slow flowing liquid

• Irregular – Indiscriminate deposit of hazardous material (contaminated responders)

The Path of a Hazardous Release

• Exposure/Contact. Anything that is in the area of the release is exposed. Contact is just that, coming in physical contact with the material. There are three time frames of exposure and contact– Short-term – Seconds, minutes, hours– Mid-term – Days, weeks, months– Long-term - Years

The Path of a Hazardous Release

• Harm. Depending on the container, product, energy involved and duration of exposure/contact, exposures may be harmed. Always base estimations of harm on worst-case scenarios

7 Steps to Identifying Hazards

1. Locations and Occupancies

2. Container Shapes

3. Transportation Placards, Labels and Markings

4. Other markings and colors (704)

5. Written Resources

6. Senses

7. Monitoring and Detection Devices

Identification

• ERG covers most identification needs

• Remember that high pressure containers usually have rounded ends and only one fitting (usually in a protected housing)

• Non pressure tanks = 3 psi or less

• Low pressure tanks = 40 psi or less

• High pressure tanks = over 100 psi

Couple of Tips

• Hydrogen Cyanide cars are no longer painted white with red stripes due to terrorist threats

• Tube module railcars are now obsolete

704

• Useful but does not tell what chemicals are stored

• Also does not tell the location

Monitoring/Detecting Devices

• There are many devices for detecting and monitoring hazardous materials.

• Use the devices to determine the scope of the incident– What material is involved– How far has it traveled– What is its concentration– Where are the safe zones?

Monitoring/Detecting Devices

• Two most commonly used detectors– Combustible gas indicators– Two, Three or Four gas monitors

Combustible Gas Indicator

4 Gas Monitor

Next Week We Will

• Discuss management of Hazmat scene

• Mitigation efforts (using a shove and such)

• Decontamination – 3 types

And answer questions you dreamed up in 7 days


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