Safety talk about compressed gases

02/05/2013Source: EHS (512) 471 3511

Airgas (866) 924 7427(training = OH204)

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Gases classification, hazards

Argon, nitrogenHelium, carbon dioxide

Hydrogen,Methylamine,

Carbon monoxide,Acetylene, ammonia…

Carbon monoxide,Phosgene, HCl

HCl, phosgene

Oxygen,nitrogen oxides (NO, NO2),

chlorine

Dangerously Reactive Gases like acetylene are very easy to ignite:

Slight temperature, pressure increases, static electricity or mechanical shock => polymerization or decomposition reactions => Fire or explosion

Oxygen: seems to be harmless but we must be very careful ( flash fires => severe burns)

If you are not sure: take a look to the Material Safety Data Sheet (MSDS)

The only safe means of determining product identity: cylinder labels (colors cannot be used) 2

Cylinder identification

1. Department of transportation, cylinder type of material of construction (3AA), workingPressure in psi (2,265)2. Serial number3. Date of manufacture4. Original owner of the cylinder5. Retest markings (month-facility-year-plus ratings-star stamp, with = 10-year retest instead of 5 and = qualifies for 10% overfill 6. Bar code label (to track cylinders)7. manufacturer’s inspection marking8. Cylinder tare 3

Under high pressure and heavy cylinders

Cylinder properties

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Storage hazards

uncontrolled rockets or pinwheels

Secured by a strap or a chain (upright position)

Arrangement of cylinders will increase the stability of secured cylinders (at least three points of contact)

Temperature < 130 degrees F

Proper ventilation (do not store in confined spaces without ventilation)

Safety caps

Incompatible gases (oxidizers and flammable gases) stored separately ( a minimum of 20 feet between cylinders)

Fire and/or explosion

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Transport hazards

uncontrolled rockets or pinwheels

Fire and/or explosion

Secured by a strap or a chain to the cart

Use the cap (remove regulators and pigtails)

Pay attention to the pathway

Proper clothing and closed-toed shoes

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UtilizationHazardous gases should be used in areas with proper ventilation (gas cabinets and chemical fume hoods)

Check the compatibility of the cylinder gas regulator: rated forFull cylinder pressure (regulators must be used!!)

Valves, pigtails, regulators all have the potential to leak1.Loosen the connection2.Check the seating surface3.Realign the connections and tighten with a wrench (not too much)4.If it still leaks, notify EHS and the gas supplier

Do not use Teflon tape (contaminants into gas stream)or lubricants (particularly with oxidizing gases)

Open valves (first cylinder valve) slowly standing to theside of the regulator

When you finished: close valves (pressure gauges = 0psi)

Highly toxic gas: contact EHS (special storage, training, monitoring may be required) 7