Trace the intercommunication system from the riser diagram into its specified system type, station capacity, and video or door-release features, then compare power source and cabling basis for the same system before treating a station schedule as coordinated.
Assemble the review package
Gather the intercom riser and station location plan, the station schedule with master and remote counts, the door hardware and electronic-security-system documentation for any video-equipped stations with door release, and the issued intercommunication system specification. This guide covers dedicated intercommunication systems, not public address systems, which are specified separately; review one system type completely before assuming a similar-looking station elsewhere shares the same type and capacity.
WBDG publishes UFGS 27 51 23: Intercommunication System as a public guide-specification reference (accessed September 24, 2026). Use your project’s issued specification and amendments for the actual comparison; the guide specification does not automatically govern your project. The checklist below is an original suggested review workflow, not a reproduction of the UFGS requirements.
Eight checks to run against the issued set
Use one record per location or system. The CSV contains the same eight prompts plus fields for source revisions, observed evidence, the review owner, the decision, and closure references.
| Check | Sources to compare | Question to resolve |
|---|---|---|
| System type assignment | Riser diagram configuration + specified Type 1 hardwired, Type 2 multiplexed, or Type 3 IP-based system | Does the riser diagram’s wiring configuration and station count match the specified system type, particularly whether the project needs the roughly 30-station limit associated with a single-master hardwired system? |
| Station capacity and spare capacity | Station schedule count + specified master station capacity and spare-capacity requirement | Does the scheduled remote-station count leave the specified spare capacity at each master station without requiring additional hardware to add stations later? |
| Video-equipped station assignment | Station location plan camera symbol + specified video master and remote station features | Does every station shown with a camera symbol correspond to a station type in the specification that actually includes the video feature, rather than an audio-only station? |
| Door release and security-system interface | Video master station door-release feature + coordinated electronic security system documentation | Where a video master station includes a door-release feature, is the associated door’s electric strike or latch coordinated with the electronic security system design rather than left as an unassigned interface? |
| Public-address distinction | Facility type and paging requirement + specified public address system exclusion | Where the facility type (such as a detention or brig area) requires a separate two-way public address system in addition to intercom, does the documentation show that system specified separately rather than substituted by the intercom? |
| Power and PoE assignment | Remote-station power note + specified 24-volt transformer or Power-over-Ethernet basis | Does the specified power method for each remote station match whether the system is documented as hardwired or IP-based with Power over Ethernet? |
| Cabling and IP compliance | Riser cabling callout + specified structured-cabling and conductor-gauge requirement for IP-based systems | Where the system is IP-based, does the cabling shown comply with the referenced structured-cabling requirements, including the specified minimum conductor gauge? |
| Acceptance testing basis | Specified frequency-response, signal-to-noise, and video test requirements + station schedule | Does the commissioning plan identify which stations receive each specified acceptance test, including video tests for camera-equipped stations? |
Worked example: a detention area without its separate paging system
Illustrative example: a detention wing’s intercom riser shows Type 2 multiplexed stations at each cell, and the intercom specification is the only communications section referenced on that sheet. The specification’s own scope note requires a separate two-way public address system for paging and monitoring in facilities of this type, in addition to the intercom system, but no public-address section appears on the referenced-sections list for the wing.
Confirm the facility’s classification and paging requirement with the project’s life-safety and security criteria, add the missing public-address section reference if required, and recheck the wing’s riser diagram for a station or speaker conflict between the two systems before closing the item.
Avoid a false conflict
An intercom system and a public address system serve different functions even where their stations sit close together on a plan; do not assume that an intercom riser alone satisfies a facility’s paging requirement without confirming the specification’s own scope exclusions.
When requirements disagree, follow the project’s document-control and clarification process. Do not assume that drawings always override specifications, or the reverse. Identify the exact sources and request an authorized decision.
Close the issue across the affected documents
Record the location or tag, drawing and specification references, issue dates, observed difference, and the decision needed. Assign an owner and keep the item open until the response identifies the governing requirement. Check the revised drawings and specification references together; a response email alone may leave the issued package inconsistent.
For the overall process, use the guide to drawing and specification conflicts. Mark an inapplicable checklist row with a reason, and distinguish a verified correction from a question that still needs design information.
Where Groundbook fits
Groundbook’s drawing and specification review helps investigate potential disagreements in the documents you supply. Include the relevant specification sections and drawing references, then verify the cited evidence with the responsible reviewers before acting on a finding.