Appeal 34765

2902.1

2902.1 Requires Plumbing fixtures shall be provided in the minimum number as shown in Table 2902.1 based on the actual use of the building or space. Uses not shown in Table 2902.1 shall be considered individually by the code official. The number of occupants shall be determined by this code.

Request for plumbing counts to be calculated based on the actual maximum number of occupants in the building (52), which is lower than the plumbing occupant load (145) due to the non-simultaneous use of the acoustic lab and the supporting office spaces. This approach aligns with the building’s specialized research function and actual occupancy patterns.

The Oregon Acoustic Research Lab (OARL) is a 14,130 SF acoustic testing facility located on the Port of Portland’s Terminal 2 site. The facility includes:

1. A full-scale acoustic testing chamber (F-1 Factory),
2. Research offices for the OARL and the Energy Studies in Buildings Lab (ESBL) (Group B),
3. Storage areas (S-1 Storage).

While the total calculated occupant load is 145, only the ESBL offices and the Acoustic Lab offices will be used simultaneously. The acoustic lab is used for intermittent, short-duration testing and is only accessed by the same researchers who otherwise occupy the supporting office spaces (office bar). The office bar includes Rooms L100, 101, 102, 105, 106, 107, 108, 109, and 110, all of which are work, control, and support rooms for the lab. During normal operation, only the office bar, ESBL (Room 100), ESBL storage (Room 100A), and Electrical Room (Room 120) will be simultaneously occupied. The total occupant load for this simultaneous-use zone is calculated to be 51.86 occupants.

Per OSSC Table 2902.1, the required number of plumbing fixtures for this occupant load is:
-Male Water Closets: 0.98 (rounded up to 1)
-Female Water Closets: 0.98 (rounded up to 1)
-Male Lavatories: 0.62 (rounded up to 1)
-Female Lavatories: 0.62 (rounded up to 1)
-Drinking Fountains: 0.49 (rounded up to 1)

Plumbing Fixtures Provided:
-2 Water Closets – both unisex and fully ADA-compliant
-2 Lavatories – one in each restroom
-1 Drinking fountain to be provided per OSSC.

The proposed fixture count accurately reflects the actual maximum number of simultaneous users of the facility. Due to the nature of the building's use as an acoustic testing lab, the testing chambers are not occupied at the same time as the office and research support zones. All plumbing fixtures are located adjacent to the occupied zones and are readily accessible to all users. The provided unisex, ADA-compliant restrooms are sufficient to serve the limited and consistent staff that operate within the office and lab zones.
Providing more fixtures based on the full calculated building occupant load would not improve hygiene, accessibility, or life safety, as the additional spaces (e.g., acoustic chambers) are never occupied concurrently and do not generate demand for additional restroom facilities.

903.2

Approved automatic sprinkler systems in new buildings and structures shall be provided in the locations described in Sections 903.2.1 through 903.2.11.

Request to omit fire sprinkler protection in both the lower acoustic chambers (1080 sqft) and the upper acoustic chamber (1044 sqft) of the Oregon Acoustic Research Lab (OARL). These chambers form a single sealed, acoustically controlled test volume that is fully enclosed within 2-hour fire-resistive construction and are used for highly sensitive acoustic performance testing. Installation of sprinkler heads or piping within these spaces would compromise their functional integrity.

The Oregon Acoustic Research Lab is a new facility located on the Port of Portland’s Terminal 2 site, developed by the University of Oregon. Its purpose is to conduct full-scale testing of wall and floor assemblies in a highly controlled acoustic environment. Two test chambers within the building—referred to as the lower and upper acoustic chambers—are dedicated to this testing and are uniquely constructed to prevent sound distortion or interference. These chambers are physically connected by a central opening through which the test specimen is slid in. The two chambers together form a sealed, acoustically isolated volume.
The lower acoustic chamber is constructed with 8-inch CMU walls and cast-in-place concrete floor and ceiling slabs, which provide a 2-hour fire-resistive shell. The upper acoustic chamber is constructed with 6-inch mass plywood panel (MPP) walls with 2-inch plywood sheathing, a cast-in-place concrete slab floor, and an 8-inch MPP ceiling. Based on testing published by the MPP manufacturer (Freres Engineered Wood, Fire Test Summary Report, July 2022), this wall and ceiling assembly has been demonstrated to provide 2-hour fire resistance per ASTM E119 (Standard Test Methods for Fire Tests of Building Construction and Materials). Together, these two chambers create a single, sealed volume entirely enclosed in 2-hour fire-rated assemblies. All interior surfaces of the lower chamber are exposed concrete, which will achieve a “Class A” Flame Spread rating. The upper chamber floor is exposed concrete and will achieve a “Class A” Flame Spread rating. The walls and ceiling, which are constructed with exposed Mass Plywood Panels, will achieve a “Class B” Flame Spread Rating (Freres Engineered Wood, Fire Test Summary Report, March 2019).

Sprinkler components would interfere with the chambers’ calibrated acoustic performance. The presence of these elements would alter reflection and absorption patterns, invalidate test results, and render the chambers unusable for their intended purpose.
Because both the lower and upper chambers are enclosed by tested and rated 2-hour fire-resistive assemblies, the combined space achieves a high level of passive fire protection. The acoustic chambers are not used for public access or continuous occupancy. They remain unoccupied for the majority of their use cycle and are only accessed periodically by a primary acoustic engineer for specimen inspection or calibration. The chambers are mostly empty other than a few pieces of acoustic equipment, such as small, portable testing instruments such as a tapping device (approximately suitcase-sized), audio speakers, condenser microphones, and lightweight cabling. No ignition sources or combustible materials are stored or used within the chambers.
To further enhance fire safety in the absence of sprinklers, the design team proposes the following supplementary protective measures: handheld fire extinguishers will be mounted immediately outside each chamber entrance; visual monitoring from the adjacent control room will allow continuous supervision during any occupied testing period; The path of travel from the lower chamber to the nearest exit is only 64 feet, and the rest of the building is fully sprinkled.
Given the extremely low fire load, fully rated enclosure, restricted and intermittent access, non-simultaneous occupancy, and the inclusion of supplemental fire safety measures, we respectfully request approval to omit sprinklers from the acoustic test chambers in order to preserve the functionality of this highly specialized and critical research environment.