New York Codes, Rules and Regulations
Title 16 - DEPARTMENT OF PUBLIC SERVICE
Chapter III - GAS UTILITIES
Subchapter C - Safety
Part 256 - Inspection And Maintenance Of Gas Holders
Section 256.9 - Preliminary precautions before entering piston chamber

Employees before entering or descending to piston chamber shall satisfy themselves that the motor driven elevator, hand operated safety hoist and folding ladders, are in a proper operating condition and that all items described herein under "First Aid and Protective Equipment" are at their specified locations.

If any item of the mechanical apparatus is not operating properly, no descent to the piston shall be made until the item is placed in proper working order. The safety basket on the hand operated safety hoist shall be ready for immediate use before descending to piston.