# Senior Mechanical Engineer — Hazardous Materials Safety Interpretation

- **operation:** document
- **citation:** 12-0213
- **title:** Senior Mechanical Engineer — Hazardous Materials Safety Interpretation
- **source type:** guidance
- **agency:** Pipeline and Hazardous Materials Safety Administration
- **status:** guidance
- **official:** true
- **published on:** 2012-12-18
- **effective on:** Not available
- **summary:** 12-0213 response to Senior Mechanical Engineer concerning 173.309, 178.36, 178.37, 178.42, 178.46, 178.50, 178.51, 178.55, 178.61.
- **machine formats:** - **json:** https://regulus.evalyn.ai/document/phmsa-interpretation-12-0213.json
- **markdown:** https://regulus.evalyn.ai/document/phmsa-interpretation-12-0213.md
- **app url:** https://regulus.evalyn.ai/document/phmsa-interpretation-12-0213
- **source url:** https://www.phmsa.dot.gov/sites/phmsa.dot.gov/files/legacy/interpretations/Interpretations/2012/120213.pdf
**body:**

<<<PAGE 1>>>

U.S. Department
of Transportation
Pipeline and Hazardous
Materials Safety
Administration
1200 New Jersey Avenue, SE
Washington, D.C. 20590
DEC 1 8 2m:~
Mr. Mark Fazzio
Senior Mechanical Engineer
UTC Aerospace Systems
4200 Airport Drive
Wilson, NC 27896
Ref. No.: 12-0213
Dear Mr. Fazzio:
This is in response to your September 11, 2012 letter requesting clarification of the
Hazardous Materials Regulations (HMR; 49 CPR Parts 171-180) as they pertain to
UN1 044, fire extinguishers. In your letter you describe two, DOT specification 39 cylinders
with a volumetric capacity of 11.7 ( cu in) and 19.6 ( cu in) and an operating pressure of 1225
psi. It is your understanding that these cylinders should be shipped as UN1 044, fire
extinguisher.
The HMR do not authorize the use of DOT specification 39 cylinders as UN1044, fire
extinguishers. When transported, each cylinder must be described with the name of its
compressed gas contents and the outside package must be properly marked and labeled in
accordance with Part 172.
The requirements for shipping fire extinguishers are found in§ 173.309. Paragraph (a) of
this section permits the use of non-specification cylinders charged with a limited quantity of
compressed gas to not more than 241 psig. Such fire extinguishers are excepted from
labeling, unless shipped by aircraft and the specification packaging requirements when
shipped under the conditions described in§ 173.309(a)(1) through (a)(3). If the
requirements of§ 173.309(a) cannot be met, a DOT specification 3A, 3AA, 3E, 3AL, 4B,
4BA, 4B240ET, or 4BW (§§ 178.36, 178.37, 178.42, 178.46, 178.50, 178.51, 178.55, and
178.61) cylinder must be used in accordance with§ 173.309(b).
I hope this information is helpful. If you have further questions, please do not hesitate to
contact this office.
Sincerely,
~~t!+
Senior Regulatory Advisor
Standards and Rulemaking Division
--------------- ----------- --------

<<<PAGE 2>>>

Fire Protection Systems
UTC Aerospace Systems
4200 Airport Dr.
Wilson, NC 27896
+1 252 246 7910 Fax: +1 252 246 8415
Mark.fauio@utas.utc.com
www.utcaerospacesystems.com
Mark Fazzio
Senior Mechanical Engineer, Fire Extinguishing Products
0 UTC Aerospace Systems
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September 11, 2012
Associate Administrator for Hazardous Material Safety
Pipeline and Hazardous Materials Safety Administration
U.S. Department of Transportation
East Building
1200 New Jersey Avenue, SE
Washington, D.C. 20590-0001
Attention: Special Permits, PHH-31
Subject: Interpretation of 49 CFR 173.309 and 172.1 02
Dear Sir/Madam:
Kidde Aerospace & Defense (KAD), a company of UTC Aerospace Systems- Fire
Protection Systems, is requesting interpretation of the 49 CFR 173.309 and 172.1 02. The
interpretation request is related to specification 39 (49 CFR 178.65} pressure vessels, KAD
part numbers 474617 and 474618. The design specifications of these cylinders are
provided below.
PIN 474617 PIN 474618
Volume, cu.in. 11.7 19.6
Charge Pressure, psig @ 70F 1225 1225 !
Identification Number UN1044 UN1044 I
Hazardous Materials Fire Extinguisher containing 1
Description compressed gas !
Actuation Device Cartridge, power device
The hazardous material description and proper shipping name per 49 CFR 172.101 is "Fire
Extinguisher''. As such, the packaging authorizations per columns SA, 88 and 8C of the
hazardous materials table indicate that in addition to the requirement of 49 CFR 173.24
and 49 CFR 178.65, that the requirements of 49 CFR 173.309 also apply.
KAD's interpretation of 49 CFR 173.309 and its sub parts are as follows:
173.309(a)- Applies: the subject part numbers are not exempt from labeling as the
extinguishers are charged to 1200 psig.
173.309(a)(1)- Applies: Agent is nonflammable, nonpoisonous and noncorrosive.
173.309(a)(2)- Applies: The extinguishers are shipped as an inner packaging.

<<<PAGE 3>>>

Fire Protection Systems
UTC Aerospace Systems
4200 Airport Or.
WHson, NC 27896
+1 252 246 7910 Fax: +1 252 246 8415
Mark.fazzio® utas.utc.com
www.utcaerospacesystems.com
Mark Fazzio
Senior Mechanical Engineer, Fire Extinguishing Products
() UTC Aerospace Systems
173.309(a)(3)(i, ii, iii, iv)- Does not apply: Requirements are for non-specification
cylinders only. The units are designed to spec. 39.
173.309(a)(4)(i, !i, iii)- Does not apply: Only applies to specification 2P & 20.
173.309(b)- Does not apply: Identifies additional specifications which are
acceptable and is not a fully inclusive list. Other specification and non-specification
cylinders are acceptable provided they meet the requirements of 173.309(a}.
In addition, KAD's interpretation of special provisions for fire extinguishers listed in the
hazardous materials table of 49 CFR 172.101 identifying 49 CFR 172.1 02 paragraphs 18
and 11 o are as follows.
Special provision 18 - Does not apply: Only applicable to fire extinguishers listed in
173.309(b).
Special Provision 11 0 - Applies: Permits the use of a cartridge, power device of
Division 1.4C or 1.4S with quantity of explosives less than 3.2 grams to be included
with each fire extinguisher without changing the classification.
Please advise if these are accurate interpretations of 49 CFR 173.309 and 172.201, as
well as UN1 044 as the appropriate identification number.
Thank you,
?JI ~-·
/ IJ~L<.A
Mark Fazzio
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