Water supply systems for non-exclusive use: The answer depends on the rules under which the network supplied by the pump-set was designed and constructed, as well as on the type of water supply. In certain very specific cases, coexistence is permitted; in others, it is prohibited.*
Table of Contents
Water Treatment Plants for Non-Exclusive Use: The Most Common Question
When there are multiple technical systems in the same building, people often wonder whether it is possible to “optimize” the space and locate the pump-set in the same room as a pressurized water system. The question is valid, but the answer cannot be generalized: it is a regulatory issue, and it varies depending on the specific situation.
The key point is to distinguish the general rule (for exclusive local use) from the exceptions permitted under well-defined conditions.
General rule: room for exclusive use in accordance with UNI EN 12845:2015
UNI EN 12845:2015 stipulates that pump room spaces must be for exclusive use (see section 10.3.1). In practice, this requirement excludes the presence of any other components or materials:
- from the pump-set;
- from its accessories.
Therefore, if you are operating in accordance with UNI EN 12845, the idea of placing an autoclave (or other equipment) in the same room conflicts with the principleof exclusive use.
Possible exception: when UNI 10779:2014 is applied
However, there is one case in which the text cited allows for a non-exclusive application: when the pump-sets are used solely to supply networks designed and constructed in accordance with UNI 10779:2014.
In this scenario, UNI 10779 itself (see section A.1.1.) stipulates that, if it is not possible to locate fire pumps in dedicated rooms, they may be located:
- limited to electric vehicles;
- in common areas shared with other technical systems;
- provided that such premises present a very low fire hazard;
- with a fire load of less than 100 MJ/m² in any case.
This is the only “window” identified in which coexistence can become feasible.
Limits of the exception: Level 1, electrical units only, fire load
The text makes it clear that admission to public spaces is not “unrestricted,” but is subject to certain limitations. Specifically, it clarifies that:
- The application complies with UNI 10779;
- is limited to the lowest hazard level (Level 1);
- These must be electrical units only;
- the premises must remain at a very low fire risk;
- The maximum fire load specified is 100 MJ/m2.
In other words: if even one of these conditions is not met, you are no longer within the scope of the exception as stated.
When exclusive use always applies (all other cases)
The text is very clear on this point: in all other cases,the exclusive use specified in UNI EN 12845:2015 applies.
Therefore, if your pump-set is not intended “solely and exclusively” to supply UNI 10779 networks, or if you do not fall under the lowest level and the conditions specified, the rule to follow remains that of a room dedicated exclusively to the pump-set and its accessories.
This conclusion is important because it prevents “broad” interpretations of the exception: admissibility is not determined by analogy, but by whether the case corresponds to the one provided for.
Caution: Combined water supply systems (sprinklers + fire hydrants)
There is another explicit point to note: in the case of combined water supply systems—that is, systems that simultaneously supply both sprinkler systems and fire hydrants—the provisions of UNI 10779 regarding location in common areas do not apply.
In this case, it is clarified that the exclusive use requirement set forth in UNI EN 12845 applies. Therefore, the presence of the sprinkler system “reinstates” the assessment based on the criterion of the room’s exclusive use.
Minimum requirements for premises: reference to UNI 11292:2019
In addition to the “exclusive room vs. common room” distinction, the text notes that the minimum requirements specified in UNI 11292:2019 apply to rooms housing pressurization units.
This step is useful for properly setting up the inspection: it is not enough to simply decide “where people can be”; one must also consider that the premises must comply with the minimum requirements set forth in the referenced standard.
Practical Checklist (Quick Decision)
Below is a practical guide based exclusively on the criteria mentioned:
- Does the pump-set supply only systems designed and built in accordance with UNI 10779:2014?
- If so, go to step 2.
- Otherwise, apply for exclusive use (UNI EN 12845:2015).
- Are you at the lowest threat level (Level 1) and using only electric vehicles?
- If so, go to step 3.
- Otherwise, apply for exclusive use (UNI EN 12845:2015).
- Does the common area have a very low fire hazard and a fire load of < 100 MJ/m²?
- If so, installation in a common area is permitted (UNI 10779, A.1.1).
- Otherwise, apply for exclusive use (UNI EN 12845:2015).
- Is the water supply a combination system (sprinklers + fire hydrants)?
- If so, apply for exclusive use (UNI EN 12845).
Conclusion
In water supply systems for non-exclusive use, the coexistence of a pump-set and a water booster pump is not a “layout” choice, but a consequence of the applicable rules: the general rule for exclusive use (UNI EN 12845), with a limited and conditional exception under UNI 10779 (Level 1, electric units only, very low hazard, and fire load < r 100 MJ/m²). In presence of a combined sprinkler and hydrant system, exclusive use takes precedence.
