The service corridor BNL-SERV/B2C is a utility passage (length: approximately 34 metres) running below ground between Lab Block B and Lab Block C. The corridor is used for moving large equipment and cryogenic tanks between blocks without travelling through the main lobby. Push-bar handles at both ends allow exit from inside without a badge; entry from the Block B side and Block C side both require only a physical push of the bar — no electronic access control.
The corridor floor is smooth epoxy, light grey. Overhead strip lighting. A single wall-mounted fire extinguisher is present at the midpoint. There are no cameras.
| Item | Location in Corridor | Description |
|---|---|---|
| SERV/TM-01 | Approx. 8 metres from the Block B entrance, left wall near skirting | Nitrile glove fiber cluster — 7 fragments, blue-grey, Size M. Laboratory analysis confirms fibre composition and coloration are consistent with BioNexus Labs lab-issue PPE (same manufacturer and batch as fragments recovered from workstation LN-07 drawer pull — E01/TM-01). |
| SERV/TM-02 | Approx. 27 metres from Block B entrance (Block C entrance side), floor | Partial shoe impression — right shoe, size approximately UK 7–8 (women's range or smaller men's). Impression made in residual moisture/cleaning product on epoxy floor. Tread pattern: consistent with closed-toe flat laboratory shoes (not trainers). |
| SERV/TM-03 | Block C push-bar handle (corridor side) | Single latent fingerprint — insufficient ridge detail for individualisation (smeared). Presence of a print confirms the handle was used on 7–8 May 2025 (corridor had been cleaned on 6 May, per BNL maintenance log). |
| Time (approx.) | Inferred Activity | Evidence Basis |
|---|---|---|
| 21:00 | Last confirmed in Conference Suite — group photograph taken | E08 (Celebration Register) |
| 21:12 | Badge (BNL-0102) exits Lab Block B — AP-04 | E02 (Access Control Audit) |
| 21:12–21:44 | Approximately 32 minutes — location unconfirmed by badge or CCTV | No badge events, no CCTV, handset inactive (E05 CDR gap) |
| 21:44 | Dr. Anil Reddy's badge enters Lab Block C | E02 |
| 21:44–22:31 | Bay B-14 (Kavitha's Tesla) remains in parking bay | E06 (Vehicle CCTV) — no bay exit event until 22:31 |
| 22:31 | Kavitha's Tesla exits Bay B-14 | E06 |
| 22:35 | Tesla exits campus | E06 (CAM-P02) |
| 23:04 | Kavitha's handset reappears on GV-N1 tower — calls Ravi Teja (6m 47s) | E05 (CDR) |