[Code of Federal Regulations]

[Title 49, Volume 2]

[Revised as of October 1, 2005]

From the U.S. Government Printing Office via GPO Access

[CITE: 49CFR174.67]



[Page 677-680]

 

                        TITLE 49--TRANSPORTATION

 

   CHAPTER I--PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, 

                      DEPARTMENT OF TRANSPORTATION

 

PART 174_CARRIAGE BY RAIL--Table of Contents

 

           Subpart C_General Handling and Loading Requirements

 

Sec. 174.67  Tank car unloading.



    For transloading operations, the following rules must be observed:

    (a) General requirements. (1) Unloading operations must be performed 

by hazmat employees properly instructed in unloading hazardous materials 

and made responsible for compliance with this section.

    (2) The unloader must apply the handbrake and block at least one 

wheel to prevent movement in any direction. If multiple tank cars are 

coupled together, sufficient hand brakes must be set and wheels blocked 

to prevent movement in both directions.

    (3) The unloader must secure access to the track to prevent entry by 

other rail equipment, including motorized service vehicles. This 

requirement may



[[Page 678]]



be satisfied by lining each switch providing access to the unloading 

area against movement and securing each switch with an effective locking 

device, or by using derails, portable bumper blocks, or other equipment 

that provides an equivalent level of safety.

    (4) The unloader must place caution signs on the track or on the 

tank cars to warn persons approaching the cars from the open end of the 

track that a tank car is connected to unloading equipment. The caution 

signs must be of metal or other durable material, rectangular, at least 

30 cm (12 inches) high by 38 cm (15 inches) wide, and bear the word 

``STOP''. The word ``STOP'' must appear in letters at least 10 cm (3.9 

inches) high. The letters must be white on a blue background. Additional 

wording, such as ``Tank Car Connected'' or ``Crew at Work'' may also 

appear.

    (5) The transloading facility operator must maintain written safety 

procedures (such as those it may already be required to maintain 

pursuant to the Department of Labor's Occupational Safety and Health 

Administration requirements in 29 CFR 1910.119 and 1910.120) in a 

location where they are immediately available to hazmat employees 

responsible for the transloading operation.

    (b) After the pressure is released, the seal must be broken and the 

manhole cover removed as follows:

    (1) Screw type. The cover must be loosened by placing a bar between 

the manhole cover lug and knob. After two complete turns, so that vent 

openings are exposed, the operation must be stopped, and if there is any 

sound of escaping vapor, the cover must be screwed down tightly and the 

interior pressure relieved as prescribed in paragraph (a)(4) of this 

section, before again attempting to remove the cover.

    (2) Hinged and bolted type. All nuts must be unscrewed one complete 

turn, after which same precautions as prescribed for screw type cover 

must be observed.

    (3) Interior type. All dirt and cinders must be carefully removed 

from around the cover before the yoke is unscrewed.

    (c) When the car is unloaded through a bottom outlet valve, the 

manhole cover must be adjusted as follows:

    (1) Screw type. The cover must be put in place, but not entirely 

screwed down, so that air may enter the tank through the vent holes in 

threaded flange of the cover.

    (2) Hinged and bolted type. A non-metallic block must be placed 

under one edge of the cover.

    (3) Interior type. The screw must be tightened up in the yoke so 

that the cover is brought up within one-half inch of the closed 

position.

    (d) When unloading through the bottom outlet of a car equipped with 

an interior manhole type cover, and in each case where unloading is done 

through the manhole (unless a special cover with a safety vent opening 

and a tight connection for the discharge outlet is used), the manhole 

must be protected by asbestos or metal covers against the entrance of 

sparks or other sources of ignition of vapor, or by being covered and 

surrounded with wet burlap or similar cloth material. The burlap or 

other cloth must be kept damp by the replacement or the application of 

water as needed.

    (e) Seals or other substances must not be thrown into the tank and 

the contents may not be spilled over the car or tank.

    (f) The valve rod handle or control in the dome must be operated 

several times to see that outlet valve in bottom of tank is on its seat 

before valve cap is removed.

    (g) The valve cap, or the reducer when a large outlet is to be used, 

must be removed with a suitable wrench after the set screws are loosened 

and a pail must be placed in position to catch any liquid that may be in 

the outlet chamber. If the valve cap or reducer does not unscrew easily, 

it may be tapped lightly with a mallet or wooden block in an upward 

direction. If leakage shows upon starting the removal, the cap or 

reducer may not be entirely unscrewed. Sufficient threads must be left 

engaged and sufficient time allowed to permit controlled escape of any 

accumulation of liquid in the outlet chamber. If the leakage stops or 

the rate of leakage diminishes materially, the cap or reducer may be 

entirely removed. If the initial rate of leakage continues, further 

efforts must be



[[Page 679]]



made to seat the outlet valve (see paragraph (f) of this section). If 

this fails, the cap or reducer must be screwed up tight and the tank 

must be unloaded through the dome. If upon removal of the outlet cap the 

outlet chamber is found to be blocked with frozen liquid or any other 

matter, the cap must be replaced immediately and a careful examination 

must be made to determine whether the outlet casting has been cracked. 

If the obstruction is not frozen liquid, the car must be unloaded 

through the dome. If the obstruction is frozen liquid and no crack has 

been found in the outlet casting, the car may, if circumstances require 

it, be unloaded from the bottom by removing the cap and attaching 

unloading connections immediately. Before opening the valve inside the 

tank car, steam must be applied to the outside of the outlet casting or 

wrap casting with burlap or other rags and hot water must be applied to 

melt the frozen liquid.

    (h) Unloading connections must be securely attached to unloading 

pipes on the dome or to the bottom discharge outlets before any 

discharge valves are opened.

    (i) Throughout the entire period of unloading and while a tank car 

has unloading equipment attached, the facility operator must assure that 

the tank car is:

    (1) Attended by a designated hazmat employee who is physically 

present and who has an unobstructed view of the unloading operation; or

    (2) Monitored by a signaling system (e.g., video system, sensing 

equipment, or mechanical equipment) that is observed by a designated 

hazmat employee located either in the immediate area of the tank car or 

at a remote location within the facility, such as a control room. The 

signaling system must--

    (i) Provide a level of surveillance equivalent to that provided in 

subparagraph (1) of this paragraph (i); and

    (ii) Provide immediate notification to a designated hazmat employee 

of any system malfunction or other emergency so that, if warranted, 

responsive actions may be initiated immediately.

    (j) Attendance is not required when piping is attached to a top 

outlet of a tank car, equipped with a protective housing required under 

Sec. 179.100-12 of this subchapter, for discharge of lading under the 

following conditions:

    (1) All valves are tightly closed.

    (2) The piping is not connected to hose or other unloading equipment 

and is fitted with a cap or plug of appropriate material and 

construction.

    (3) The piping extends no more than 15.24 centimeters (6 inches) 

from the outer edge of the protective housing.

    (k) In the absence of the unloader, a tank car may stand with 

unloading connections attached when no product is being transferred 

under the following conditions:

    (1) The facility operator must designate a hazmat employee 

responsible for on-site monitoring of the transfer facility. The 

designated hazmat employee must be made familiar with the nature and 

properties of the product contained in the tank car; procedures to be 

followed in the event of an emergency; and, in the event of an 

emergency, have the ability and authority to take responsible actions.

    (2) When a signaling system is used in accordance with paragraph (i) 

of this section, the system must be capable of alerting the designated 

hazmat employee in the event of an emergency and providing immediate 

notification of any monitoring system malfunction. If the monitoring 

system does not have self-monitoring capability, the designated hazmat 

employee must check the monitoring system hourly for proper operation.

    (3) The tank car and facility shutoff valves must be secured in the 

closed position.

    (4) Brakes must be set and wheels locked in accordance with 

paragraph (a)(2) of this section.

    (5) Access to the track must be secured in accordance with paragraph 

(a)(3) of this section.

    (l) As soon as a tank car is completely unloaded, all valves must be 

made tight by the use of a bar, wrench or other suitable tool, the 

unloading connections must be removed and all other closures made tight.

    (m) Railroad defect cards may not be removed.

    (n) If oil or gasoline has been spilled on the ground around 

connections, it



[[Page 680]]



must be covered with fresh, dry sand or dirt.

    (o) All tools and implements used in connection with unloading must 

be kept free of oil, dirt, and grit.



[Amdt. 174-26, 41 FR 16092, Apr. 15, 1976, as amended by Amdt. 174-26A, 

41 FR 40685, Sept. 20, 1976; Amdt. 174-43, 48 FR 27699, June 16, 1983; 

Amdt. 174-68, 55 FR 52678, Dec. 21, 1990; 56 FR 66280, Dec. 20, 1991; 

Amdt. 174-81, 60 FR 49111, Sept. 21, 1995; Amdt. 174-83, 61 FR 28678, 

June 5, 1996; 68 FR 61941, Oct. 30, 2003; 70 FR 20034, Apr. 15, 2005]