The use of fire automatic sprinkler system

It varies with location. Where are you? I can't tell to use SI or U.S. In most places there is a building code, or a state building code it lists the hazards in there. You are going to have to look in the building code. Some places an office building more than 7500 square feet, you will need sprinklers. Density is your next thing you should know. A typical office layout, the sprinkler heads are 10'-0" feet on center.

In general, it is not needed in a non public area.

It changes when public can enter the building without entrance regulations (a store, ...)

From which moment you need to install sprinklers is depending on the authority having jurisdiction: in most cases the fire chief of you region.

Special cases are listed in laws (chemical plants with a Seveso classification, ...)

Contact your local fire chief and he will tell you what you have to do. When he tells you to install sprinkler, you will have to. He will not do this to block your activities, he does it to protect the local community and you and your business. More than half of the companies that experience a mayor fire do not survive it, how good you are insured doesn't mather. (customers find other ways of supply and do not come back)

There are others that can ask to install sprinklers: insurance companies. But this can be disputable when you go out for another company or fee.

The spacing is by type and combustion load. the 10' is an average.

Regardless of the regulations sprinklers are a good idea, especially in multi story structures.

I have seen the effectiveness of these systems on a couple of occasions and on both the fire was well and truly out before the fire brigade even arrived on site.

There have been many arguments put forward about the damage they cause if accidentally set off but when you look at how effective they are at extinguishing a fire at the early stage and preventing its spread there is no question.

If you think they may be a good idea then more than it's a pretty good idea to put them in.

We have them in our warehouse as business support.

Nobody asked for it, but out warehouse supports a $200.000.000 market.

I used to work in a mayor sprinkler company and the questions we got were each time: do we need to have it? Is there a law?

The only reason to install it is common sense. And when installed right by a decent installer (not the cheapest) the risk of accidental opening is low.

Actually, and contrary to much of what has been said, the sprinkler requirements are covered in the International Building Code (IBC) Chapter 9 "Fire Protection Systems" and the NFPA Life and Safety Code Supplement 3 " A Brief Introduction to Sprinkler Systems for Life and Safety Code Users", provides a good introdcution to the regulatoy and funtctional requirements.

I've been told that the upcoming edition of the Life & Safety Code will call for sprinklers in all residences as well. The requirement for installation of sprinklers (commercial and/or residential) will vary from jurisdiction to jurisdiction. Not all States have a uniform building code (eg. Texas) where every incorporated city makes up their own, adopts one, or goes without. Contact the local Fire Chief, Fire Marshal, or City Administrator for direction. Often, the published local ordinances are available in the local library.

The requirements depend on where you are and what code your local authority has adopted. The IBC is okay, but it is not in force everywhere. The NFPA codes, especially the Life Safety codes, are in effect in more jurisdictions - mainly because they are really good codes. You have to know what your local jurisdiction requires for minimums. Once you know what your minimum requirements are, then you have to go about the common sense piece.

Like Masu stated, even if not required sprinklers are a good idea. You have to analyze your risk - what you stand to lose from a fire and how likely a fire is, as well as determine whether or not the business can recover. Don't forget to figure in the human loss potential.

If you stick with good equipment and a reputable installer, you should be good for years. Also very important is the routine maintenance (checks and services) - don't skimp on that!

Another consideration for your sprinkler system, you should see a significant reduction with your insurance rates.

As the others have stated, it is up to the local jurisdiction having the authority in your area (your local fire marshal). You will also want to explore fire extinguisher placement, while you are at it.

Good Luck!

Consult with a local Professional Engineer. They are familiar with the local codes and can give you advise and design the systems, if required.