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Water pressure boosting system pump and tank (C) Daniel FriedmanWater Pressure Booster Pump & Tank FAQs
Questions & answers about water pressure boosting pumps & systems

Questions & answers about how to choose & install a water pressure booster pump:

FAQs about water pressure increase by using a booster pump systems.

This article series describes the use of water pressure boosting systems that add a pump and pressure tank to improve water pressure and flow, including improving water pressure & flow on the upper floors of tall buildings.

InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers, products, or services discussed at this website.

Water Pressure Boosting Pump & System FAQs

Water pressure booster pump closeup (C) Daniel FriedmanThese questions were posted originally at WATER PRESSURE BOOSTER PUMP - the home page for this topic. You will want to check the advice given there.

Our photos at page top and just here show a typical water pressure booster pump and tank system for sale at Don Pedro's Ferreteria in San Miguel de Allende.

[Click to enlarge any image]

On 2018-10-29 - by (mod) -

Brett

You posted this question and we replied at https://inspectapedia.com/water/Water_Pressure_Booster_Pumps.php

Help me manage our workload by posting questions or comments on just one page.

Thanks.

On 2018-10-29 by Brett

I had a constant pressure inline water pump professionally installed in the basement of my single story home. Incoming pressure is around 30psi; the pump is set-up to supply the outgoing water to the house around 60psi. During demand, the pump cycles on for 3-4 seconds and stops for 3-4 seconds, etc.

When the pump stops, a single 'clunk/thud' type noise can be heard behind the basement wall where the water pipe enters the house.

Currently the water pressure TANK shows 54psi. I recall my plumber telling the tank should be around 42psi (+/- 2). Question is: could the noise I'm hearing be caused by the pressure tank having too high pressure?

Also worth noting, the demand from my irrigation system has the pump running steady for the duration of an irrigation zone -- the pressure maintains a constant 60psi. But there is no 'clunk/thud' when the system cycles to the next zone.

On 2018-06-15 - by (mod) -

Yes, but if you do have a pressure tank and it's left with no air charge then your pump will short cycle and ultimately be damaged.

On 2018-06-14 by Ihsan

Will booster pump works with zero air pressure at tank?

On 2018-01-09 - by (mod) -

Scott

This sounds dangerous to me - TURN OFF the pump. Running at 100 psi risks bursting a pipe or tank that can in turn not just cause a flood but can injure someone.

From the brown water it sounds as if the well is being exhausted and/or a control is debris clogged and not working properly.

You may be able to find and clear the pressure control switch for the pump, or replace it.

On 2018-01-09 by Scott

booster pump running flat out, it does not shut off. Water coming from the pipes is now brown. Pressure gauge is showing 100psi. Outside temperature has been -15F for about a week. Water coming into the house 3ft below grade.

On 2017-06-07 - by (mod) -

Doc, if you do not have the manual for your pump see our WATER PUMP MANUALS page at

https://inspectapedia.com/water/Water-Pump-Repair-Manuals.php

On 2017-06-07 - by (mod) -

Doc

Goulds technical manual for the GT Irrigator series pumps gives five reasons that the pump might not run:

1. Motor thermal protector tripped.
2. Open circuit breaker or blown fuse.
3. Impeller binding.
4. Motor improperly wired.
5. Defective motor.

Was it running before you had this problem? If so the thermal reset may have tripped. The Goulds GT pump uses a thermal overload switch (internal) that will automatically re-set after the motor has cooled-down.

If that's not the case I would proceed in these three steps or phases:

1. confirm that there is proper voltage to the motor terminals - and of course that you've wired the pump as per the data tag or instructions
2. disassemble the pump to confirm that the impeller is not jammed or bound-up
3. test the motor itself - search InspectApedia.com using the search box just above for ELECTRIC MOTOR DIAGNOSIS for detailed help
4. replace the motor if it's confirmed to be defective

If you do not have the installation and operation manual for the Goulds irrigation pump, when I've got my set uploaded I will post a link to them here - later this morning.

You can contact the company directly:
Xylem Inc.
2881 East Bayard Street Ext., Seneca Falls, NY 13148
Phone: (866) 325-4210 • Fax: (888) 322-5877
www.gouldswatertechnology.com

On 2017-06-07 by Sprinkler Doctor

Water pressure entering booster pump from city line is 75 psi. It's use is for a baseball field. I have a 2hp gourds pump GT20 with relay but no pressure switch. But pump not kicking on? Wiring is correct, checked twice. Working on 240 volts

On 2018-10-30 by (mod) -

Brett

re your question about why during demand, your water pressure pump cycles on for 3-4 seconds and stops for 3-4 seconds,

That sounds as if you may be missing a pressure tank - on the system or there could be an obstruction in the outlet piping.

Here is what the pump manual tells us:

The Inline System needs a small pressure tank placed on the pump outlet to maintain constant pressure.

The tank supplies water while the pump ramps up to speed and in circumstances where only a small amount of water is required for a short period of time. In addition, the tank prevents water hammer by acting as a system buffer.

This buffer also helps to prevent pressure spikes when there is a sudden change in demand. For 12 gpm (45 lpm) flow or greater, minimum pressure tank size is 4 gallons (15 L); for 12 gpm (45 lpm) flow, minimum pressure tank size is 2 gallons (7.5 L).

Pressure Tank Pre-charge (PSI) The pressure tank pre-charge setting should be 70% of the system pressure sensor setting as indicated in the preceeding table. - see the IO Manual table on page 3.

If you don't have the IO manual for your pump you can obtain one from

On 2018-10-30 by Brett

Brett said:
Thank you for responding... I don't see the reply I posted earlier today so will try again...

I have the Little Giant In-Line CP, Model # 25LGIL1100N4.

- link deleted by moderator, see image above.

Little Giant pumps (Franklin Electric) website is littlegiant.com -

With that info, it's pretty easy to find the install diagram. Plumber's design matched the diagram pretty closely. He added a bypass to be able to go back to a non-pump-assisted flow.

First, thank you for the reply. I appreciate your time and willingness to help.
The pump is a Little Giant CP. http://littlegiant.com/products/water-systems/constant-pressureboosting-systems/inline-cp/
Model # : 25LGIL1100N4

Above is a picture of the Install instructions which the plumber followed pretty well from what I can tell...
<<i'm having trouble getting a menu to appear after choosing "add image" >>

...but you can find the installation PDF pretty easily by Googling "little giant constant pressure" and looking for the PDF, "Constant Pressure System -- Little Giant Pump"

On 2018-10-29 by (mod) - review the pump manufacturer's instructions about pressure tanks, pressure settings, pump cycling con trols

Brett

Let's start with a careful review of the specific pump brand and model and thence its installation instructions.

If you installed a pump that is designed specifically to work *without* a pressure tank, and as you have a pressure tank installed, that could be causing the trouble you describe.

On 2018-10-29 by Brett - constant pressure inline water pump cycling issue

I had a constant pressure inline water pump professionally installed in the basement of my single story home. Incoming pressure is around 30psi; the pump is set-up to supply the outgoing water to the house around 60psi. During demand, the pump cycles on for 3-4 seconds and stops for 3-4 seconds, etc.

When the pump stops, a single 'clunk/thud' type noise can be heard behind the basement wall where the water pipe enters the house. Currently the water pressure TANK shows 54psi. I recall my plumber telling the tank should be around 42psi (+/- 2).

Question is: could the noise I'm hearing be caused by the pressure tank having too high pressure? Also worth noting, the demand from my irrigation system has the pump running steady for the duration of an irrigation zone -- the pressure maintains a constant 60psi. But there is no 'clunk/thud' when the system cycles to the next zone.

On 2018-10-10 by (mod) -

It's possible, but I don't know for sure because I don't know how your water is being delivered, or whether it's coming from above or below, or what pipes you share in common.

On 2018-10-09 by Subbarao

I am in 5th floor in my apartment 4th floor owners fixed pressure pump for their rain shower in the bath rooms . Is it effects our 5th floor water flow in bath rooms waterfle

On 2018-08-28 by (mod) -

Can - sure. Permitted or "may" - (to be picky about language) - probably, though you may find a dispute with your other flat owners on water usage and on who pays the water bill.

On 2018-08-28 by Maurice Shukla

Can one flat owner drawing water from a common water tank instal a booster pump for his water needs ?

On 2018-08-03 16:18:34.326533 by cris

I am on the 3rd floor, water flow is faint at times - city water.
can we install a water pump and a reservoir tank to keep steady water supply?

On 2018-07-29 04:02:23.764415 by alok kumar

my building height is 60 feet from ground and i have jet pump for tank but water pressure is not much as i need which jet is good and if i need water pressure pump for push up the water.
8881322551

On 2018-05-07 by (mod) - calculate the total flow rate of water usage that you are going to provide to your sprinkler system

Moses,

What you need to do is to calculate the total flow rate of water usage that you are going to provide to your sprinkler system and then compare that with the capacity of both the pump and the well flow rate that is your water source.

Any one of a number of pumps can work but the pumping capacity needs to be adequate both in gallons per minute and after taking into consideration the lift if the pump has to lift water from one elevation to another. Every pump comes with a table that gives those numbers.

On 2018-05-06 by Moses - kind and capacity of water booster pump can be use in a farm that have 60 water sprinklers

Please what kind and capacity of water booster pump can be use in a farm that have 60 water sprinkler to wet at a time? I

On 2018-04-16 by (mod) - On 3rd floor, my flush tank takes 10 min to refill.

Harsh

As your 3rd floor toilet is 2 floors under the water tank I suspect that the problem is not water pressure in the system but a bad toilet fill valve.

Often a toilet fill valve can become clogged with minerals or debris, or the small valve and riser that feed water to the toilet could be blocked.

I would start by replacing those components. Let me know what you find and we'll take it from there.
Hold off on adding a pressure booster for now.

On 2018-04-16 by Harsh Bafna

Liked this article. I have one query, hope you can solve this.

My building is of 4 floors and there is a tank on the top.

On 3rd floor, my flush tank takes 10 min to refill. What should I do to make it refill in 10 seconds only? Do I need to use some pressure pump? Please provide solution. Plz reply your solution on email ID : harsh.bafna@transformsolution.net. It will be very helpful

On 2018-01-25 by (mod) -

Saravan, why not first confirm that there is no blockage in the piping, then second add a pressure booster pump such as described above.

On 2018-01-23 by Saravanan

In my house water stored in roof winter tank.water outlet goes in terrace for 30 feet and down words in 15 feet and straight to 25 feet and upwards to 8 feet but we can't get water flow.

Tank is in terrace level. Kindly give me a solution

On 2017-11-01 by (mod) - pumping water from a cistern

Not necessarily Jack.

If for pumping water from a cistern, and if you are using a one-line jet pump, that pump can generally be adapted to Pump from a shallow well that is less than 27 feet deep.

if in your cisternand you are using a free-standing submerged sump pump type pump to send water up out of the cistern to your water supply,, that pump is not going to function if dropped into a deep well.

and if your well is a deep well, that is more than 27 feet, you would need to use either a two-line jet pump or submersible well pump.

On 2017-11-01 by jack

are cistern pumps interchangeable with well pumps

On 2017-10-12 by (mod) - piping materials used to move water up and down hilly terrain in Costa Rica and Mexico

Tony I have seen a variety of piping materials used to move water up and down hilly terrain in Costa Rica and Mexico as well as the U.S. including galvanized iron (no-freezing climates) and various plastics including ABS and PVC.

In regions where freezing is a risk there will need to be a measure to avoid that damage, burying below the frost line, drain-back systems, or (less practical) heating systems. Depending on distance, pumping stations are needed enroute.

A common procedure is to pump up to a point from which water can continue onwards by gravity, perhaps using an intermediate reservoir.

On 2017-10-12 by Tony O NEILL

Hi I was wondering if water had to be transported over great distances over mountains or forest regions what type of pumping and piping system would have to be used

On 2017-10-12 by (mod) - pumping water over large uneven terrain

Tony I have seen a variety of piping materials used to move water up and down hilly terrain in Costa Rica and Mexico as well as the U.S. including galvanized iron (no-freezing climates) and various plastics including ABS and PVC.

In regions where freezing is a risk there will need to be a measure to avoid that damage, burying below the frost line, drain-back systems, or (less practical) heating systems.

Depending on distance, pumping stations are needed enroute. A common procedure is to pump up to a point from which water can continue onwards by gravity, perhaps using an intermediate reservoir.

On 2017-10-12 by Tony O NEILL

Hi I was wondering if water had to be transported over great distances over mountains or forest regions what type of pumping and piping system would have to be used

On 2017-10-03 by Anonymous

Buster pump previously it works in high pressure but now it given a low pressure why?

On 2017-10-02 - by (mod) - how much excess water will be consumed when we use a pressure pump

None

On 2017-10-02 by s n naik

can you let me know as to how much excess water will be consumed when we use a pressure pump

On 2017-08-13 by Bobby H

Our home pressure is 45 PSI and the flow rate is 1.6 (1 point 6) GPM. This explains why if I flush the toilet the water at the sink slows to a trickle.

My neighbor has the same problem and says the City water line is to small. The City says the pressure is legal and won't help us.

A plumber is willing to install a water pressure booster but says that may not help much when using more than one fixture at the same time. I understand the concept of the pump can only work with the volume of water available at the inlet. Is there any options I'm not thinking of?

My neighbors have adopted the "just living with it" attitude and I'm fine with that if no options. The pump and inlet are in the basement. Thank you for your suggestions.

On 2017-07-31 by Sunil

I need to know difference between VSD operated water booster pump and pressure booster water pump

On 2017-06-02 by (mod) - fixing jumping pipes usually means correcting water hammer

Daze

Jumping pipes can certainly occur when a water pump starts or stops - a notorious source of leaks. But I agree with what I infer from your comments that looking into water hammer controls might help - along with taking care to secure the pipes against movement.

See WATER HAMMER NOISE DIAGNOSE & CURE at https://inspectapedia.com/plumbing/Water_Hammer_Noise.php

On 2017-06-02 by Dazed

We have a pressure booster package installed in the basement of a 7 story building with a diaphragm type hydro-accumulator tank installed on the top floor to keep the size down.

The piping for the tank is 1-1/2" & connects from the tank to the 6" loop for the 7th floor. Occasionally the piping between the tank & the loop jumps drastically & will swing back & forth in the cradle mounts for a moment.

It is odd because it will sometimes do this when the booster pump isn't even running, sometimes it will do it after the booster pump has been on for a few minutes & sometimes it will do it while the booster is completely off.

The booster is a good system with check valves installed correctly at each of the 3 pumps on the station. It's almost like extreme hammering, but way more than anything I've ever seen. What could be causing this?

The cut-in pressure for the top floor is 40 PSI & the initial fill on the tank is 35 psi. Any idea what is causing the piping to swing & jump wildly at odd times?

On 2017-05-30 by (mod) - deliver pond water for landscaping

Mark,

That's a 15 gpm flow rate from your well - which should be adequate for lots of outdoor uses. But we can't confuse flow rate at the well with

- the pump's output rate or capacity in gpm

- the effect of restrictions in the piping system: filters, controls, pipe diameters, lengths, elbows, sprinkler heads

Yes you could add a pressure tank and booster pump or a simple pressure-sensitive booster pump like the new Grundfos SCALA2

More about methods for boosting water pressure and the Grundfoss SCALA2 variable speed pump are

at WATER PRESSURE BOOSTER PUMP.

There's something you could try first - avoiding running wires out to whoknowswhere. What about installing some control valves at the heads of the closest sprinkler zones so that you can partly close them, slowing the water volume into those zones and giving more water to the more distant zones?

That's simpler and cheaper even than installing pressure regulators at the zone heads - another alternative.

On 2017-05-30 by Mark

I have a 1hp, 950 gph shallow water pump with a 30/50 pressure switch and tank that I am using to supply water from my pond to my landscaping.

The watering zones that are closest to the pump are working fine. But, as the zones get further away from the pump, the water pressure decreases.

I'm sure some of this is due to friction from the irrigation piping and tubing. Can I put a pump inline between the current pump and the zones that are located further away to increase my water pressure to the sprinklers in these zones>? If so, what type of pump should I look for?

On 2017-05-29 by (mod) - water use increases when we boost water pressure

Lata

In my OPINION, yes, unless we take great care, we will use more water when we convert a gravity-fed water supply system (say from a rooftop water tank) to a water supply system that uses a pressure-pump.

That's because the higher "pressure" provided by the pump will increase the water flow rate in litres per minute or gallons per minute at the building's sinks, showers, tubs. (Flush toilets won't use more water than before, they'll just fill faster).

Even with a pressure booster pump set to a rather low 25 psi you'll see a much greater flow rate at the sink or tub faucet. And if your building water supply is from a low pressure municipal supply the same effects will be seen.

You can buy back some of the increased water usage by changing faucets and shower heads to low-flow fixtures.

On 2017-05-29 by Latasiddharth @gmail.com

Does consumption of water increase when we use a pressure pump

On 2017-05-23 by (mod) - delivering water in Columbia

Jack

It's perfectly reasonable to use a pressure boosting system to do what you want. After all, plenty of people also are pumping water out of a ground level or below ground cistern or tanaka that collects rainwater.

see WATER PRESSURE BOOSTER PUMP

and also, WATER PUMP VARIABLE FREQUENCY / VARIABLE SPEED DRIVE (VFDs)

Pressure sensitive or "tankless" pressure booster pumps are widely used in my area of Mexico where we just installed one.

The new Grundfos SCALA2 will give you the pressure you want provided you're not lifting the water too many stories up.

Here's a photo of the system as we were installing it

https://inspectapedia.com/water/Grundfos-Scala2-Pump-Installation-300-DJFs.jpg

On 2017-05-23 by Jack

Dear Plumbers,

First of all thank you for your interest. I live in Colombia and in a rural part to boot.

Everyone here has a water tank for reserve in case there is no water due to a line break or some other problem. Most people have their tank on top of their house which is gravity fed into the home. In my case we have 2, 1100L tanks which I would like hooked up with a pump to pressure our house.

I prefer this to building a huge column strong enough to support it.

The thing is that with gravity pressure its not nearly enough to reach the 20PSI needed to turn on the water heater.

Can I have a pump between the main line that enters the property and the reserve tanks, set so that when there is a drop of pressure or a loss of water all together we still have something like 40PSI?

We also don't want to just run a pump for our water pressure needs 24/7. Really that increased water pressure is needed for taking a shower and thats it. The rest of the time anything is better than nothing.

Here they sell JET pumps as well as the membrane style pumps, but I don't know what is best for me or what size tank/power of pump.

All our water lines are 1/2in and are located close to the main tanks if that makes a difference.

On 2017-04-19 by (mod) : how to use the The Darcy-Weisbach equation vs the Hazen-Williams equation to calculate friction head loss in water piping systems

John, the Engineering Toolbox to whom I sometimes turn for greater depth in engineering calculations offers this comment

The Darcy-Weisbach equation with the Moody diagram is considered to be the most accurate model for estimating frictional head loss for a steady pipe flow.

Since the Darcy-Weisbach equation requires iterative calculation an alternative empirical head loss calculation like the Hazen-Williams equation may be preferred: - 2017/04/18 original source http://www.engineeringtoolbox.com/hazen-williams-water-d_797.html

The engneers also tell us to add a coefficient to the William Hazen equation for pipe material. - http://www.engineeringtoolbox.com/hazen-williams-coefficients-d_798.html

And they offer a cute little head loss calculator at http://apps.engineeringtoolbox.com/head-loss-water-pipe-a_15.html

You'll see that you need, besides pipe diameter and pressure, pipe length, elbows, etc. Pump output ratings like the one you mention also are lift dependent - though lift may be trivial in your application.

h = 0.2083 (100 / c)1.852 q1.852 / dh4.8655 (1)

where

h = friction head loss in feet of water per 100 feet of pipe (fth20/100 ft pipe)

c = Hazen-Williams roughness constant

q = volume flow (gal/min)

dh = inside hydraulic diameter (inches)

Note that the Hazen-Williams formula is empirical and lacks a theoretical basis. Be aware that the roughness constants are based on "normal" conditions with approximately 1 m/s (3 ft/sec).

Now plugging in your data and using a smoothness coefficient of 140 (typical smooth pipe interior) I got

31.5 (ft H2O/100 ft pipe) head loss

13.6 (psi/100 ft pipe) head loss

473 (ft H2O) head loss

205 (psi) head loss

13.3 (ft/s) velocity

Perhaps the high head loss is a factor of that long run of 1500 feet - that's pretty long for a 2" pipe.

On 2017-04-19 by John

Just to clarify, I have 280 ft of 3 inch pipe before the softener, and 1500 ft of 2 inch pipe after the softener.

I work at a metal finishing shop. Supplied water pressure from the city is 48 psi, in a 3 inch line. By the time some process water gets used, the pressure drops before reaching my 30 cubic inch water softener. Pressure drops to approximately 28 psi.

I need 60 psi to lift the resin bed and properly backwash. I am looking at a booster pump that will supply 130 gpm at 85 psi to correct this problem.

When I use William Hazen's equation to determine pressure loss in a 2 inch pipe at 1500 ft, it comes out to be over 100 psi. I know this isn't true. (PVC pipe, schedule 80). Am I using this equation improperly or should I be using a different formula to calculate?

On 2017-04-04 by (mod) : InspectApedia does not sell any product nor service, including pumps or tanks

To protect reader confidence, we do not sell any product nor service so cannot offer price quotes.

Before choosing a pump or changing out a pump you've bought you will want to determine the water flow rate needed, water source, pump lift height, and then to compare those with the specifications for the specific pump you are considering.

On 2017-04-04 by yunus

We have guest house / we do not have problem BUT . like to installl 2x 750lt jo jo tank/ pls advice size pump is required.

i have purchace tank with a pump 3.7 / how much will a bigger cost.

On 2017-03-16 by (mod) re: using a pressure tank with a pressure booster pump?

It would be unusual for a municipal water supply pressure to be below 7 psi in most countries - you don't say where you live.

But certainly installing a combination of water pressure tank and booster pump or a type of booster pump that doesn't require a separate pressure tank can deliver improved water pressure.

A common-sense approach would be to consider not just the pressure you need but the quantity of water you neeed - as that may argue for a large pressure tank in addition to a pump.

On 2017-03-16 QUIKCLEAN said:

My machine needs 7 to 145 psi pressure, as building pressure is not adeqaute for my machine, tell me attached link is useful or not.NOT.

On 2017-03-15 19:19:39.457499 by (mod) re: do you need a booster pump for water pressure or not?

It's not clear why you need a booster pump unless your current building pressure is inadequate for your machine.

On 2017-03-15 by QuickClean

RE-posting without screaming capital letters

Qiuikclean said:
I want contineous flow of water in my electrolux washing machine, but condition is that machine will take water automatic from pump, so suggest me booster pump is useful for me and how?

On 2017-02-28 by (mod) re: need for a foot valve or check valve

Lokuge

Indeed if you are describing a well pump, you need a non-return valve or check valve, either at the pump or at the bottom of the well piping ( a foot valve) - otherwise when the pump stops, water drains back into the well from the water tank and building piping.

That causes not just extra pump cycling (that can burn up the pump motor) but it can also cause loss of prime and thus loss of all water.

Rae:

See my advice to Lokuge above. Sounds like you need a replacement foot valve or check valve on your system.

On 2017-02-28 3 by Lokuge

When there is no non return valve fitted before the pump, the water return through the pump impel-or.
when this happens, the pump runs even when water is not in use.


...

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