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Course 736 - Introduction to Process Safety Management

Safety guides and audits to make your job as a safety professional easier

Mechanical Integrity and Hot Work Permit

PSM mechanical integrity requirements apply to pressure vessels and storage tanks.
PSM mechanical integrity requirements apply to pressure vessels and storage tanks.

Mechanical Integrity

OSHA believes it is important to maintain the mechanical integrity of critical process equipment to ensure it is designed and installed correctly and operates properly.

PSM mechanical integrity requirements apply to the following equipment:

  • pressure vessels and storage tanks;
  • piping systems (including piping components such as valves);
  • relief and vent systems and devices;
  • emergency shutdown systems;
  • controls (including monitoring devices and sensors, alarms, and interlocks); and
  • pumps.

The employer must establish and implement written procedures to maintain the ongoing integrity of process equipment.

Training

Employees involved in maintaining the ongoing integrity of process equipment must be trained in an overview of that process and its hazards and trained in the procedures applicable to the employee's job tasks.

The employer must train each employee involved in maintaining the on-going integrity of process equipment in an overview of that process and its hazards and in the procedures applicable to the employee’s job tasks to assure that employees can perform their jobs in a safe manner.

1. PSM mechanical integrity requirements apply to _____.

a. personal protective equipment, fall restraint systems, mechanical lift systems
b. pressure vessels, storage tanks, piping systems, vent systems
c. pressure vessels, electrical sub-stations, fire-suppression systems
d. personal protective equipment, storage tanks, mechanical lift systems

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Inspection and testing must be performed on process equipment, using procedures that follow recognized and generally accepted good engineering practices.
Inspection and testing must be performed on process equipment.

Inspection and Testing

Inspection and testing must be performed on process equipment, using procedures that follow recognized and generally accepted good engineering practices. The frequency of inspections and tests of process equipment must be consistent with and conform to applicable manufacturers' recommendations and good engineering practices, or more frequently if determined to be necessary by prior operating experience.

Each inspection and test on process equipment must be documented, identifying the date of the inspection or test, the name of the person who performed the inspection or test, the serial number or other identifier of the equipment on which the inspection or test was performed, a description of the inspection or test performed, and the results of the inspection or test.

The employer must document each inspection and test that has been performed on process equipment. The documentation must include:

  • the date of the inspection
  • name of the person who performed the inspection or test,
  • the serial number or other identifier of the equipment inspected or tested,
  • a description of the inspection or test, and
  • the results of the inspection or test.

2. Each inspection and/or test on process equipment must be _____.

a. randomly performed
b. able to meet the ANSI ISO 28000 standard requirement
c. limited to problematic equipment
d. documented

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Equipment Deficiencies and Quality Assurance

Equipment deficiencies outside the acceptable limits defined by the process safety information must be corrected before further use. In some cases, it may not be necessary that deficiencies be corrected before further use, as long as deficiencies are corrected in a safe and timely manner, when other necessary steps are taken to ensure safe operation.

In constructing new plants and equipment, the employer must ensure that equipment as it is fabricated is suitable for the process application for which it will be used. Appropriate checks and inspections must be performed to ensure that equipment is installed properly and is consistent with design specifications and the manufacturer's instructions.

The employer also must ensure that maintenance materials, spare parts, and equipment are suitable for the process application for which they will be used.

3. In the Equipment deficiencies outside the acceptable limits _____ must be corrected before further use.

a. identified by EPA guidelines
b. defined by EPA and OSHA regulations
c. as required by HAZWOPER rules
d. defined by the process safety information

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A permit must be issued for hot work operations conducted on or near a covered process.
A permit must be issued for hot work operations.

Hot Work Permit

A permit must be issued for hot work operations conducted on or near a covered process. The permit must:

  • document that the fire prevention and protection requirements in OSHA regulations (1910.252(a)) have been implemented prior to beginning the hot work operations;
  • it must indicate the date(s) authorized for hot work; and
  • identify the object on which hot work is to be performed. The permit must be kept on file until completion of the hot work.

4. What document is used to ensure all safety requirements have been met prior to beginning hot work operations?

a. Welding authorization permit
b. Hot work permit
c. Entry permit
d. Fire watch permit

Check your Work

Read the material in each section to find the correct answer to each quiz question. After answering all the questions, click on the "Check Quiz Answers" button to grade your quiz and see your score. You will receive a message if you forgot to answer one of the questions. After clicking the button, the questions you missed will be listed below. You can correct any missed questions and check your answers again.

Exercise

Optional Exercise

Scenario:

Art and Ray were sent to the Tank Farm to replace bearings on an isopropanol pump located on the alcohol pad. They found the bearings “frozen" in place. When Art told his supervisor they would have to pull the pump, he said, “Let’s see if we can't pull those bearings in place; we've got too much downtime in that area already." First they tried to loosen the bearings with a bearing heater, a powerful electric heat gun, without success. Ray then called a welder who heated the casing with her torch until the bearings came free. While the welder was there, the supervisor had her weld brackets on an I-beam so he could install a “Warning-Flammable Area" sign.

A piece of slag from the welding rolled into a nearby pile of damp wooden shims. After the mechanics and the welder left the area, the wood began to smolder and then burst into flames. At the same time an operator began to charge ethanol to his unit by remote computer control. The ethanol transfer pump started to leak around its mechanical seal creating a pool of alcohol on the pad. The vapors from the pool traveled towards the fire, which then ignited them.

The fire spread instantly to the pump and grew in intensity as the heat increased the size of the leak. The tank farm operator saw the fire, sounded the alarm and attacked the fire with an extinguisher. She was overcome by vapors and fell unconscious. Quick response by the in-plant emergency response team saved her life and stopped a potentially disastrous fire.

Task

Think about the incident and, based on your experience, answer the following questions.

What could have been done to prevent this fire?

Click on the button below to see the "book answers."

Importance of Welding Location

Weld or cut only in locations specifically designated for this purpose unless you have obtained approval of the job and have taken the necessary precautions to eliminate fire and explosion hazards.

Do not weld in any location outside the shop unless you take the necessary precautions and get authorization. Before you weld in any compartment, room, tank, or adjacent space which contains or which has contained flammable or explosive materials, liquids, or vapors, make sure they are:

  • made safe,
  • tested, and
  • proclaimed safe.

Restrictions

Allow welding or cutting only in areas that are or have been made "fire safe."

  • When you cannot move work practically, as in most construction work, the area must be made safe by removing combustibles or protecting combustibles from ignition sources.
  • If you cannot remove fire hazards, install suitable guards, or take special precautions as discussed below, then welding and cutting should not be performed.
  • If you cannot move the object to be welded or cut and if not all the fire hazards can be removed, use guards to confine the heat, sparks, and slag, and to protect the immovable fire hazards.

Prohibited Areas

Do not permit welding or cutting in the following situations:

  • in areas not authorized by management
  • in sprinklered buildings while such protection is impaired
  • in the presence of explosive atmospheres (mixtures of flammable gases, vapors, liquids, or dust with air)
  • inside uncleaned or improperly prepared tanks or equipment which have previously contained such explosive atmospheres or have the potential for explosive atmospheres
  • in areas with an accumulation of combustible dust
  • in areas near the storage of large quantities of exposed, readily ignitable materials such as bulk sulfur, baled paper, or cotton

Special Precautions for Fire Prevention

Relocation of combustibles: If possible, relocate all combustibles at least 35 feet (10.7 m) from the work site. When relocation is not possible:

  • protect combustibles with flame-proofed covers, or
  • shield combustibles with metal or asbestos guards or curtains.

Floors: Where combustible materials such as paper clippings, wood shavings, or textile fibers are on the floor, sweep the floor clean within a radius of 35 feet (10.7 m). In addition:

  • If floors are combustible, keep them wet, covered with damp sand, or protected by fire-resistant shields.
  • Protect workers operating arc welding or cutting equipment from shock where floors have been wet down.

Hot Work

Hot work is any work that involves burning, welding, using fire- or spark-producing tools or that produces a source of ignition. Follow these general best practices below for hot work.

  • Do not perform hot work where flammable vapors or combustible materials exist.
  • Relocate work and equipment outside of the hazardous areas, when possible.
  • Make suitable fire-extinguishing equipment immediately available in a state or readiness. The equipment may consist of pails of water, buckets of sand, hose, or portable extinguishers dependent upon the nature and quantity of the combustible material exposed.
  • When performing hot work, assign a fire watch to guard.

Fire Watch: A worker designated as the "Fire Watch" is required whenever welding or cutting is performed in locations where other than a minor fire might develop, or any of the following conditions exist:

  • Appreciable combustible material, in building construction or contents, closer than 35 feet (10.7 m) to the point of operation.
  • Appreciable combustibles are more than 35 feet (10.7 m) away but are easily ignited by sparks.
  • Wall or floor openings within a 35-foot (10.7 m) radius expose combustible material in adjacent areas including concealed spaces in walls or floors.
  • Combustible materials are adjacent to the opposite side of metal partitions, walls, ceilings, or roofs and are likely to be ignited by conduction or radiation.

Fire Watch Duties: The duties of a qualified fire watch include:

  • They must have fire-extinguishing equipment readily available.
  • Train them in how to use fire-extinguishing equipment.
  • They must be familiar with facilities for sounding an alarm in the event of fire.
  • They must watch for fires in all exposed areas, try to extinguish them only when obviously within the capacity of the equipment available, or otherwise sound the alarm.
  • They must maintain a fire watch for at least a half hour after completion of welding or cutting operations to detect and extinguish possible smoldering fires.

Welding or Cutting Containers

Used containers: Do not weld, cut, or perform other hot work on used drums, barrels, tanks or other containers until you clean them.

  • Clean them so thoroughly to make absolutely certain there are no flammable materials present or any substances such as greases, tars, acids, or other materials which when subjected to heat, might produce flammable or toxic vapors.
  • Disconnect or blanket any pipelines or connections to the drum or vessel.

Venting and purging: Vent all hollow spaces, cavities or containers to permit air or gases to escape before preheating, cutting or welding. You should purge with inert gas.

Video

Video

Watch this CSB video about the key lessons to prevent flammable vapor explosions caused by welding and cutting.

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