# Invinity Energy Systems — Hazardous Materials Safety Interpretation

**Citation:** 25-0058  
**Type / status:** guidance / guidance  
**Agency:** Pipeline and Hazardous Materials Safety Administration  
**Effective:** Not stated  
**Published:** 2025-06-10

25-0058 response to Invinity Energy Systems concerning 171.15, 173.159.

## Document text

<<<PAGE 1>>>

1200 New Jersey Avenue, SE
Washington, DC 20590
U.S. Department
of Transportation
Pipeline and Hazardous
Materials Safety
Administration
June 10, 2025
Derek Polman-Tuin
Director
Invinity Energy Systems
1250 E. Pender Street
Vancouver, B.C., Canada V6A 1W8
Reference No. 25-0058
Dear Mr. Polman-Tuin:
This letter is in response to your April 23, 2025 letter requesting clarification of the Hazardous
Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to wet batteries transported via
highway. Specifically, you explain that your company designs and manufactures vanadium flow
batteries classified as “UN2794, Batteries, wet, filled with acid, electric storage, 8.” You state
that these batteries contain a non-flammable, aqueous electrolyte solution containing vanadium
sulfate. You are seeking confirmation that the transportation of these batteries, as described
below and in accordance with the requirements of § 173.159(e), is not subject to any other
requirement of the HMR.
• The battery is shipped fully discharged.
• The power and energy storage elements (i.e., the tanks) of the battery are physically
separated and the power elements (i.e., stacks) contain no stored energy.
• No voltage on the terminals (0 V).
• Stacks have no exposed terminals to prevent short circuiting.
• Stacks are firmly secured within a rigid metal racking system that separates each stack to
prevent short circuiting.
• The metal racking system containing the stacks is firmly secured and integrated into a
20-ft International Organization for Standardization/Convention of Safe Containers
(ISO/CSC) certified steel container.
• The 20-ft ISO/CSC certified container has re-enforced structures, fixtures, and secondary
containment.
• No other hazardous material is shipped with the complete unit.
• No other materials are transported on the vehicle.

<<<PAGE 2>>>

Based on the information as described and the photographs you provided, it is the opinion of this
Office that the batteries meet the requirements of § 173.159(e) for highway transport. Please note
that batteries transported in this manner are still subject to incident reporting requirements in
§ 171.15.
I hope this information is helpful. Please contact us if we can be of further assistance.
Sincerely,
Dirk Der Kinderen
Chief, Standards Development Branch
Standards and Rulemaking Division

<<<PAGE 3>>>

Baker, Y.
25-0058
From: INFOCNTR (PHMSA)
To: Dodd, Alice (PHMSA)
Cc: Hazmat Interps; Baker, Yul (PHMSA)
Subject: FW: Request for a letter of interpretation
Date: Wednesday, April 30, 2025 9:29:55
Attachments: image001.png
Letter of Interpretation_DOT.docx
Hi Alice,
Please see the attached interpretation request. Let us know if you need anything.
Sincerely,
Janaye
From: Derek Polman-Tuin <DPolmanTuin@invinity.com>
Sent: Tuesday, April 29, 2025 6:58 PM
To: INFOCNTR (PHMSA) <INFOCNTR.INFOCNTR@dot.gov>
Cc: Benjamin Duperthal <bduperthal@invinity.com>; Derek Polman-Tuin
<DPolmanTuin@invinity.com>
Subject: Request for a letter of interpretation
You don't often get email from dpolmantuin@invinity.com. Learn why this is important
CAUTION: This email originated from outside of the Department of Transportation (DOT). Do
not click on links or open attachments unless you recognize the sender and know the content
is safe.
Good morning,
Please see attached request for a letter of interpretation.
The letter outlines our understanding of the regulations, our battery classification and detailed information
(with pictures), which confirms it meets the highway(Road) requirements under 49CFR 173.159(e).
Mailing Address:
Invinity Energy Systems
Attn: Derek Polman-Tuin
1250 E. Pender Street
Vancouver, BC
Canada
V6A 1W8
Please feel free to reach out to me if you have any questions.
Thank you,
Derek

<<<PAGE 4>>>

Derek Polman-Tuin
Director, Global Logistics & Trade
Compliance
dpolmantuin@invinity.com
VAN:+1.604.335.7117

## Provenance

- Official: Yes
- Source: <https://www.phmsa.dot.gov/sites/phmsa.dot.gov/files/2025-06/250058.pdf>
- Source ID: `phmsa`
- SHA-256: `202387029451e28269eeabc1aad711b7d5d3cf699e441f5f4932cc7ff307b7f1`
- Retrieved: 2026-08-20T00:59:31.977Z
- Exported: 2026-08-23T10:58:13.697Z
- Document slug: `phmsa-interpretation-25-0058`

### Source metadata

```json
{
  "materialSubtype": "interpretation",
  "interpretationArea": "hazardous_materials",
  "representation": "full_text_from_official_pdf",
  "companies": [
    "Invinity Energy Systems"
  ],
  "individuals": [
    "Derek Polman-Tuin"
  ],
  "refIds": [
    "25-0058"
  ],
  "catalogDates": [
    "2025-06-10"
  ],
  "catalogParts": [
    171,
    173
  ],
  "catalogRowCount": 2,
  "sourceRecordUrls": [
    "https://www.phmsa.dot.gov/node/77851"
  ],
  "linkedAttachmentUrls": [],
  "unavailableResponseUrls": [],
  "duplicateRepresentationUrls": [],
  "citedSections": [
    "171.15",
    "173.159",
    "173.159(e)"
  ],
  "catalogPageUrls": [
    "https://www.phmsa.dot.gov/regulations/title49/section/17115",
    "https://www.phmsa.dot.gov/regulations/title49/section/173159"
  ],
  "pdfUrls": [
    "https://www.phmsa.dot.gov/sites/phmsa.dot.gov/files/2025-06/250058.pdf"
  ],
  "representations": [
    {
      "viewUrl": "https://www.phmsa.dot.gov/sites/phmsa.dot.gov/files/2025-06/250058.pdf",
      "detailUrl": null,
      "detailHtmlPath": null,
      "pdfUrl": "https://www.phmsa.dot.gov/sites/phmsa.dot.gov/files/2025-06/250058.pdf",
      "pdfArtifactPath": "data/sources/phmsa-interpretations/25-0058-bb0d4045ab.pdf",
      "pdfArtifactSha256": "a45a0f253b2315883ba47ab1a4110cf756bf5e1861d3508ff70f0de59243998f",
      "extractedTextPath": "data/sources/phmsa-interpretations/25-0058-bb0d4045ab.v2.txt",
      "extractedTextSha256": "6002763620789e0a166ec9c0a353e4028224bf5d76f16f07c3355c478f65ba0d",
      "pageCount": 4,
      "extractionVersion": 2
    }
  ],
  "caveat": "Interpretations apply regulations to the facts presented and do not create independently enforceable requirements.",
  "jurisdiction": "US"
}
```
