Short Answer
The full title of FM DS 8-30 is Storage of Carpets, and it deals with storing carpet rolls in racks, cubicle racks and tubes. What sets it apart is that it builds the ceiling sprinkler design on a large number of sprinklers at low pressure and gives most of the protection load to in-rack sprinklers and manual response.
Identity and Scope of the Data Sheet
The copy used here is dated January 2003, with an April 2025 interim revision, and has 8 pages (cover, PDF p.1); according to Appendix B, the April 2025 interim revision consists only of reaffirming that the document is technically accurate (PDF p.8).
The scope section (Section 1.0) draws the limits: carpets made of wool, cotton, man-made fibers and synthetic blends, including plastic or rubber pads bonded to these carpets. For carpet underpads made of polyurethane, foam rubber or rubber-coated fiber, DS 8-9 applies (PDF p.2).
Carpet rolls and carpet pieces standing on the floor (cartoned or uncartoned) are protected per the DS 8-9 recommendations for Class 4 commodities (in current FM terminology Class 4 is not a separate class: the April 2014 revision of DS 8-1 removed Class 4 and treats this commodity as cartoned unexpanded plastic (CUP); the relevant DS 8-9 tables carry the heading "Class 4 and CUP", DS 8-1 Appendix B and DS 8-9 Tables 3 and 8); polyurethane, foam rubber or rubber-coated fiber carpet pads are also protected per the DS 8-9 guidance for expanded plastic commodities (Section 2.4.1, PDF p.3). For the framework of commodity classes see the DS 8-1 commodity classification article and the DS 8-9 Class 1-4 and plastics storage article.
Storage Arrangement Rules
Section 2.3.1 sets the carpet arrangement in racks in three items (PDF p.3):
- Transverse flue spaces of at least 2 to 4 in. (51-102 mm) are kept at the vertical uprights; in back-to-back racks, a gap of about 1 ft (0.3 m) is left between the vertical members.
- To reduce water damage, the lowest carpet storage tier is at least 4 in. (102 mm) above the floor.
- In standard carpet racks with storage of 12 ft (3.6 m) or less and no in-rack sprinklers, at least 8 ft (2.4 m) of open space is left about every 100 ft (30.5 m) along the length of the rack to break fire spread.
For tube storage, the tube length should preferably be equal to or greater than the carpet roll, the carpet should not project more than 6 in. (152 mm) from either end of the tube, and the lowest tube tier should be at least 4 in. (102 mm) above the floor (Section 2.3.2, PDF p.3). Section 2.3.3 requires storage to be kept at least 36 in. (915 mm) below the sprinkler deflectors. The flue space concept is defined in the flue space glossary article; with carpet, this gap is not only an air path but the path by which water reaches the lower tiers.
Ceiling Sprinkler Design
Section 2.4.2 requires protection per Table 1, with sprinklers also provided in the transverse aisle tunnels of rack storage. The system should preferably be wet-pipe or preaction; dry-pipe systems are considered acceptable. In new installations the sprinkler temperature rating should be 286°F (141°C) (PDF p.3).
The structure of Table 1 is unusual: the operating pressure is fixed at 7 psi (0.5 bar) in every column, and what changes is the number of sprinklers (DS 8-30, Table 1, PDF p.4).
| Storage arrangement | Storage height | Ceiling height / clearance | Wet system (pendent or upright) | Dry system (upright, 280°F) |
|---|---|---|---|---|
| Standard carpet rack | Up to 12 ft (3.6 m) | Up to 30 ft (9.0 m) | 30 sprinklers @ 7 psi (0.5 bar) | 40 sprinklers @ 7 psi (0.5 bar) |
| Standard carpet rack | Above 12 ft (3.6 m), in-rack sprinklers required | Not more than 20 ft (6.1 m) | 20 sprinklers @ 7 psi (0.5 bar) | 25 sprinklers @ 7 psi (0.5 bar) |
| Cubicle rack | Up to 15 ft (4.5 m) | Up to 30 ft (9.0 m) | 30 sprinklers @ 7 psi (0.5 bar) | 40 sprinklers @ 7 psi (0.5 bar) |
| Cubicle rack | Above 15 ft (4.5 m), in-rack sprinklers required | Not more than 20 ft (6.1 m) | 20 sprinklers @ 7 psi (0.5 bar) | 25 sprinklers @ 7 psi (0.5 bar) |
| Tube storage | Up to 25 ft (7.5 m) | Up to 30 ft (9.0 m) | 30 sprinklers @ 7 psi (0.5 bar) | 40 sprinklers @ 7 psi (0.5 bar) |
For wet systems the table lists K11.2 (K160), K14.0 (K200), K16.8 (K240), K22.4 (K320) and K25.2 (K360) options, both quick and standard response; in the extended coverage K25.2 EC (K360EC) column the number of sprinklers is halved (PDF p.4). For K-factor families see the site's K-factor table.
Section 2.2.1 states that this data sheet also assumes there are no roof vents or draft curtains; where permanent vents exist, they should be arranged for manual operation (PDF p.3). For installation details the data sheet refers to DS 2-0, which is covered in the DS 2-0 sprinkler installation article.
In-Rack Sprinklers
Section 2.4.3.1.1 gives the general rules (PDF p.5): nominal 160°F (70°C) FM Approved in-rack sprinklers in all in-rack installations; a quick-response listing for K14.0 (K200) and smaller, quick or standard response for larger K-factors; a minimum operating pressure of 7 psi (0.5 bar). In-rack systems can be wet, dry, preaction or refrigerated-area type; gridded piping is recommended only for wet systems, and for dry-type in-rack systems the maximum water delivery time is 60 seconds based on operation of the hydraulically most remote in-rack sprinkler.
Arrangement by rack type:
| Item | Standard carpet rack | Cubicle rack |
|---|---|---|
| In-rack sprinkler threshold | Storage above 12 ft (3.6 m) | Storage above 15 ft (4.5 m) |
| Vertical spacing | Every 8 ft (2.4 m) | Every 15 ft (4.5 m) |
| Storage left above the top level | Not more than 5 ft (1.5 m) | Not more than 10 ft (3.0 m) |
| Rack shallower than 12 ft (3.6 m) | A single line in the middle of the rack, spacing not more than 12 ft (3.6 m) | Same |
| Rack 12 ft (3.6 m) deep or more | Within 24 in. (600 mm) of each rack face, horizontal spacing not more than 12 ft (3.6 m) | Same |
| Hydraulic design | 22 gpm (85 L/min) from the most remote 8 in-rack sprinklers; with more than one level, 22 gpm (85 L/min) from the most remote 14 sprinklers (7 on each of two levels) | Same |
Source: DS 8-30, Sections 2.4.3.2 and 2.4.3.3, PDF p.5.
Two further rules bind the design. First, even where storage height stays within the 12 ft (3.6 m) limit in standard racks or 15 ft (4.5 m) in cubicle racks, if in-rack sprinklers are installed, the ceiling demand can be taken from the next row of Table 1, that is the value given for the higher storage (PDF p.5). Second, if the clearance between the top of storage and the ceiling exceeds 20 ft (6.0 m), in-rack sprinklers are installed at the top of the rack so that only one tier of storage is left above the top level (PDF p.5-6).
Section 2.4.3.1.3 requires the water demands of the in-rack and ceiling systems to be balanced at the point where the two systems connect.
Hose, Water Supply and Alarm
Section 2.4.4 asks for 1-1/2 in. (38 mm) small hose stations with combination straight stream and spray nozzles, spaced so that at least one hose stream can be applied to every point of the rack; the hose should be no longer than 100 ft (30.5 m) and the supply independent of the nearby in-rack and ceiling sprinklers (PDF p.6). Under Section 2.4.5, the water supply must meet the sprinkler demand of Table 1 together with a 500 gpm (1900 L/min) hose demand for at least two hours.
Section 2.4.6 gives the alarm side with its reason: because carpet fires develop relatively slowly and carpet warehouses have a particular arrangement, manual response can be very effective in the early stage; Class III or higher alarm service per DS 9-1 should therefore be provided (PDF p.6).
Fire Behaviour and Water Damage
Section 3.1.1 reports the results of large-scale fire tests with carpets stored in racks: the fire developed vertically and in a fan shape from floor level to the top of the rack, affecting more storage on the upper tiers than on the lower ones. In-rack sprinklers were effective at the tier where they were installed and to some extent one or two tiers below. The same section states two sentences clearly: vertical barriers in racks are not a substitute for in-rack sprinklers, and because carpet fires smoulder, manual response is extremely valuable for complete extinguishment (PDF p.6).
Water damage is not a side topic in this data sheet but a design input. Section 2.1.1 notes that carpet storage is highly susceptible to water damage and asks for forklift operators to be trained not to damage in-rack sprinkler systems; painting sprinkler piping and nearby rack members is very helpful for alerting operators (PDF p.2).
Field Note
The most frequent violation of this data sheet on site comes from the ceiling design looking easy. Because the pressure in Table 1 is fixed at 7 psi (0.5 bar), the design is thought to be "comfortable", but the choice of row in the same table depends on the in-rack sprinkler decision: as soon as storage in a standard rack goes above 12 ft (3.6 m), in-rack sprinklers become mandatory and the clearance is limited to 20 ft (6.1 m) (Table 1 and Section 2.4.3.2, PDF p.4-5). An operator who later adds one tier to the storage height has changed the whole protection regime without realising it.
The second point is that in-rack sprinklers are the most fragile component. The forklift warning of Section 2.1.1 and the balance in Section 2.4.3.1.2 between "protect the pipe from mechanical damage but do not disturb the distribution" are solved not on the drawing but by placement on site; when the on-site check before installation is skipped, either the sprinkler gets broken or the water does not reach the storage.
Checklist
- Determined whether the stored product falls under DS 8-30 or DS 8-9 (carpet underpads go to DS 8-9)
- Carpet rolls and pieces on the floor assessed separately as Class 4/CUP commodity per DS 8-9
- Rack type classified as standard, cubicle or tube, and the Table 1 row chosen accordingly
- 2-4 in. (51-102 mm) transverse flue spaces kept at the uprights; lowest tier at least 4 in. (102 mm) above the floor
- Storage at least 36 in. (915 mm) below the sprinkler deflectors
- If the in-rack threshold is exceeded, vertical spacing and the limit on storage left on top met
- In-rack hydraulic design done at 22 gpm (85 L/min) over 8 or 14 sprinklers
- Ceiling and in-rack demands balanced at the connection point
- 1-1/2 in. (38 mm) hose stations placed with an independent supply to reach every point of the rack
- Water supply meets the table demand plus a 500 gpm (1900 L/min) hose allowance for 2 hours
- Class III or higher alarm service per DS 9-1 provided
- Forklift operators trained on in-rack sprinklers; piping and rack members marked
Frequently Asked Questions
What storage does DS 8-30 cover?
Under Section 1.0 it covers storage of carpets made of wool, cotton, man-made fibers and synthetic blends, including plastic or rubber pads bonded to these carpets. For storage of carpet underpads made of polyurethane, foam rubber or rubber-coated fiber, DS 8-9 applies.
When are in-rack sprinklers needed in carpet racks?
Under Section 2.4.3.2, in-rack sprinklers are needed in standard carpet racks for storage heights above 12 ft (3.6 m); they are placed every 8 ft (2.4 m) vertically, and no more than 5 ft (1.5 m) of storage is left above the top in-rack level. In cubicle racks the threshold is 15 ft (4.5 m), the vertical spacing 15 ft (4.5 m) and the storage left on top no more than 10 ft (3.0 m).
How large must the water supply be for carpet storage?
Under Section 2.4.5, the water supply must be able to meet the sprinkler demand shown in Table 1 together with a 500 gpm (1900 L/min) hose demand for at least two hours. Section 2.4.4 also asks for 1-1/2 in. (38 mm) small hose stations spaced so that at least one hose stream can reach every point of the rack.
Do vertical barriers in racks replace in-rack sprinklers?
No. DS 8-30 Section 3.1.1 states it plainly: vertical barriers in racks are not a substitute for in-rack sprinklers. In full-scale tests the fire developed vertically and in a fan shape from the floor to the top of the rack, and in-rack sprinklers were effective at their own tier and to some extent one or two tiers below.
References
- FM Property Loss Prevention Data Sheet 8-30, Storage of Carpets, January 2003, Interim Revision April 2025. Sections used: Sections 1.0-1.1 and 2.1.1 (PDF p.2), 2.2.1, 2.3.1-2.3.3, 2.4.1-2.4.2 (p.3), Table 1 (p.4), 2.4.3.1-2.4.3.3 (p.5), 2.4.4-2.4.6 and 3.1.1-3.1.2 (p.6), 3.1.2.2-3.1.2.4 and 4.1 (p.7-8), Appendix B (p.8).
- FM Global, Property Loss Prevention Data Sheets: https://www.fmglobal.com/research-and-resources/fm-global-data-sheets
- selvi.org, FM Global DS 8-9: Class 1-4 and Plastic Storage
- selvi.org, FM Global DS 2-0: Sprinkler Installation Rules
- selvi.org, K-factor table: K57 to K480
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Download MEP Calc on the App StoreFM Property Loss Prevention Data Sheet 8-30, Storage of Carpets, January 2003, Interim Revision April 2025; clause, table and page references are listed under References. General information only: the current edition governs, and design must be carried out by a qualified engineer.