Can a firefighter wearing an air mask with a 4500 psig cylinder use the Quick-Fill System to transfill air to a fellow firefighter wearing an air mask equipped with a low-pressure 2216 psig cylinder?
Yes. Quick-Fill System quick-disconnect fittings are identical for oth low-pressure (2216 psig) and high-pressure (4500 psig) air asks. This capability allows wearers of low- and high-pressure air asks to transfill air between each other. Additionally, the Quick-Fill system male adapter assembly is equipped with a special self-reseating relief valve that automatically vents at approximately 2500 psig. This relief valve is designed to prevent over pressurization from accidental over filling from a 4500 psig air source.

Can the Quick-Fill System be used with all MSA cylinders?
MSA has received NIOSH certification extensions for use of the Quick-Fill System on its NIOSH-certified pressure-demand air masks using MSA carbon fully-wound composite cylinders.

The Quick-Fill System can help at the scene of a fire. Can it be used for routine cylinder filling back in the shop?
Yes. MSA offers a variety of Quick-Fill System hoses with standard CGA fittings or outlets on one end to facilitate connection to your cylinder filling station. If the Quick-Fill System is used in this manner, MSA recommends that the cylinder be allowed to "cool"until the pressure stabilizes, as with any routine filling method. The cylinder must then be topped off to ensure that it is fully pressurized prior to storage.

Does the unusually high pressure inside the Quick-Fill System Hose make it rigid or awkward to use?
No. Because of the flexibility of the materials used to construct Quick-Fill System hoses, they remain very pliable even when under pressure.

Will the ends of a pressurized Quick-Fill System hose "whip"freely when disconnected?
No. The Quick-Fill System fittings incorporate check valves which prevent air from escaping, and thus, the hose from "whipping" when disconnected.

I thought that cylinders had to be placed in a water tank during refilling. Aren't there federal regulations that require this?
No. The practice of placing cylinders in a water tank during normal refilling operations was started when steel cylinders were predominantly used. This practice was based upon the premise that heat generated from rapid air compression of air would transmit through the steel cylinder wall to the surrounding water. Heat dissipation would then reduce the pressure loss as the cylinder air cooled. Since the fiberglass over-wrap insulates the aluminum liner from water, this practice has no beneficial effect on reducing internal cylinder temperature. Therefore, MSA does not recommend that cylinders be placed in a water tank during refilling.

Don't most SCBA manufacturers recommend a 300 psi/minute fill rate because higher fill rates may adversely affect air cylinders?
No. The 300 psi/minute fill rate recommendation currently advised by most SCBA manufacturers is not based upon concerns that higher fill rates adversely affect air cylinders. The idea behind the very conservative 300 psi/minute fill rate recommendation is to minimize heat buildup resulting from air compression during cylinder refilling. This heat buildup forces air inside the cylinder to expand, thus causing a higher pressure-gauge reading than the actual volume of air would produce at room temperature (70° F). Test data from millions of cylinder refills, combined with the fact that many fire departments for years have successfully used fill rates significantly higher than the 300 psi/minute recommendation, clearly demonstrate that this recommendation is highly conservative and simply not applicable for today's professional firefighter who may need to replenish his air supply quickly. A much higher fill rate is warranted, needed, and certainly more in keeping with today's technology.

How long does it take for two 30 minute-rated cylinders to equalize pressure, if one is empty and the other full, when using the EBS (3-foot) Quick-Fill System hose between two SCBA wearers?
Approximately 40 seconds, regardless of whether the cylinder is low-pressure (2216 psig) or high-pressure (4500 psig).

How long does it take to refill a low-pressure (2216 psig) 30-minute-rated cylinder from a cascade system or a compressor/reservoir pressurized to approximately 2300 psig using the Quick-Fill System?
Approximately 50 seconds.

How long does it take to refill high-pressure (4500 psig) cylinders from a compressor/reservoir or cascade system pressurized to 4500 psig?
Approximately 45 seconds for 30-minute-rated cylinders and 60 seconds for 60-minute-rated cylinders.

What is meant by average fill rate?
An average fill rate is the total pressure put into a cylinder divided by the amount of time (in minutes) it takes to reach that total pressure. For example, if it takes 45 seconds to fill a high-pressure (4500 psig) cylinder to 4500 psig, then the average fill rate is 6000 psi/minute. In practice, air speed transfer is actually faster than 6000 psi/minute at first and then slow to less than that as the cylinder fills. Hence, the fill rate averages 6000 psi/minute.

What is the maximum average fill rate allowed by the Quick-Fill System?
MSA's cylinder valve used on all MSA cylinders incorporates a restrictive orifice. This orifice allows a maximum average fill rate of 6000 psi/minute provided that the secondary air source used to fill the cylinder does not exceed 4500 psig.

Did MSA conduct a test program to determine the structural and thermal effects of rapidly filling MSA cylinders?
Yes. Over many years, MSA and our cylinder suppliers have jointly conducted an extensive testing and research program. This test program was specifically designed to determine structural and thermal effects of rapidly filling cylinders using average fill rates up to 13,500 psi/minute - more than twice the maximum average fill rate that the Quick-Fill System allows.Based upon these findings and allowing a safety margin of over 2:1, MSA established a maximum average fill rate recommendation of 6000 psi/minute for all MSA fully-wound composite and steel cylinders.

Does the rise in cylinder air temperature/pressure caused by the Quick-Fill System mean I won't have a fully pressurized cylinder?
Not necessarily. With the Quick-Fill System, as with any cylinder refilling method, a cooling effect occurs after cylinder refill which causes a slight decrease in cylinder pressure. This actual pressure loss occurs at a rate of roughly 2 psi/minute. The rate is based upon tests using a composite II cylinder at room temperature, a 6000 psi/minute average fill rate, and inlet air having a temperature of 70° F. Therefore, when the Quick-Fill System is used at a fire scene where firefighters typically use their cylinders within 30 minutes after refilling, pressure loss is not discernible. If however, the Quick-Fill System is used for routine filling operations, MSA recommends the cylinder be allowed to "cool" until the pressure stabilizes. At this point, the cylinder must then be topped off to ensure that it's fully pressurized prior to storage. This of course, is standard operating procedure with any refilling method.

Don't the cylinder liner and air get extremely hot when you use the Quick-Fill System?
No. Liner and air temperature may rise a maximum or 46° F, according to our extensive test program conducted with cylinder manufacturers. This finding was determined by installing numerous thermocouples along a production cylinder liner's exterior wall prior to wrapping that liner with high-strength fiberglass filaments. To achieve the highest temperature increase possible, MSA used a 60-minute-rated cylinder which has the highest pressure (4500 psig) and greatest volume; in short, a cylinder that requires the longest filling time. Starting at room temperature (70° F) for both the cylinder and inlet air, and using an average fill rate of 6000 psi/minute, the hottest point measured was 116° F at the bottom of the cylinder - a maximum temperature increase of 46° F. As long as air temperature entering the cylinder or the cylinder liner temperature itself does not exceed approximately 200° F (both of which are extremely unlikely), this rise in temperature is not enough to affect the cylinder's structural integrity.

Doesn't the Quick-Fill System exert tremendous pressure on the cylinder liner, thus making it risky to refill the cylinder while it is positioned on my back?
No. The internal pressure on the cylinder wall during refilling, whether using an average fill rate of 300 psi/minute or 6000 psi/minute (which the Quick-Fill System uses), is no greater than the total stress on the cylinder when fully charged. In other words, there is no greater stress exerted during the filling process than when a fully-charged cylinder is worn, as millions of wearers have safely done over the past five decades.

Does the rapid filling of MSA cylinders weaken the cylinder structure over time?
No. Our joint research and testing program concluded that there are no adverse effects on the structural integrity of MSA fully-wound composite cylinders due to rapid filling. This finding is further demonstrated by extensive quality assurance testing conducted by cylinder manufacturers on MSA cylinders for nearly 15 years. As part of this on-going test program, a cylinder manufacturer pressurizes MSA cylinder production samples using a rapid pressurization cycling system similar to the Quick-Fill System. These tests are preformed to meet required Department of Transportation (DOT) qualification tests. During the 15-year period, over 1,100 MSA cylinders have been rapidly pressurized over 10,000 times each, from 0 psig to working pressures of 4500 or 2216 psig. Each cylinder was pressurized at a fill rate far exceeding 13,500 psi/minute. None of these cylinders exhibited any structural degradation due to the rapid-fill method.