# Performance Specification Gap in Division 27 Communications submittals

> Source: https://deviationcheck.com/divisions/27-communications/performance-specification-gap/

A measurable performance property in the submittal (rating, capacity, tolerance, efficiency) does not meet what the spec requires.

## What to look for in Division 27 Communications

Key performance parameters in Div 27 submittals:
- **Cabling category** (Cat 5e, Cat 6, Cat 6A, Cat 8) - must match spec exactly; lower category is always a blocker
- **Fiber type** (OM3, OM4, OM5 multimode; OS2 single-mode) - lower grade does not support specified bandwidth/distance
- **Fiber connector type** (LC, SC, MPO/MTP) - must match spec for patching compatibility
- **Fiber strand count** per cable (12, 24, 48, 72, 96, 144) - must meet or exceed spec
- **Cable pathway fill ratio** - 40% maximum per TIA-569; submitted conduit sizing must support cable count
- **Telecommunications room size** - must meet TIA-569 minimums for served area
- **Rack unit capacity (RU)** and depth - must accommodate specified equipment with growth
- **Power density per rack (kW)** - submitted power distribution must support heat load
- **Wireless AP coverage** (dBm at cell edge) - submitted AP model/placement must meet design coverage
- **DAS coverage** (signal strength threshold, typically -85 dBm) - submitted system must cover all required areas
- **Cable test results** - permanent link or channel test per TIA-568; submitted test equipment must match spec
- **Bandwidth support** (1G, 10G, 25G, 40G, 100G) at specified distances
- **Plenum vs riser vs general-purpose cable jacket** - must match installation environment

## Severity

Default grade: Blocker. Always a Blocker when the gap touches life-safety or structural performance.