Unexpected releases of toxic, reactive, or flammable liquids and gases in processes involving highly hazardous chemicals have been reported for many years. Incidents continue to occur in various industries that use highly hazardous chemicals which may be toxic, reactive, flammable, or explosive, or may exhibit a combination of these properties.
Regardless of the industry that uses these highly hazardous chemicals, there is a potential for an accidental release any time they are not properly controlled. This, in turn, creates the possibility of disaster.
Several major disasters involving highly hazardous chemicals drew international attention to the potential for major catastrophes; the public record in the U.S. is replete with information concerning many other less notable releases of highly hazardous chemicals.
Hazardous chemical releases continue to pose a significant threat to employees and provide impetus, internationally and nationally, for authorities to develop or consider developing legislation and regulations to eliminate or minimize the potential for such events.
On July 17, 1990, the U.S. Dept. of Labor, OSHA issued the “Process Safety Management of Highly Hazardous Chemicals” (PSM) (29 CFR 1910.119), containing requirements for the management of hazards associated with processes using highly hazardous chemicals to help assure safe and healthful workplaces.
OSHA’s PSM standard emphasizes the management of hazards associated with highly hazardous chemicals and establishes a comprehensive management program that integrates technologies, procedures, and management practices.
The Clean Air Act Amendments and the PSM Standard
Section 304 of the CAAA requires that the Secretary of Labor, in coordination with the Administrator of the Environmental Protection Agency (EPA), promulgate a PSM standard to prevent accidental releases of chemicals that could pose a threat to employees.
The CAAA also requires that the PSM standard include a list of highly hazardous chemicals which includes toxic, flammable, highly reactive, and explosive substances.
CAAA Requirements for the PSM Standard
The CAAA requires that the standard include a list of highly hazardous chemicals which includes toxic, flammable, highly reactive, and explosive substances. These requirements have become widely known as the “14 PSM Program Elements.”
OSHA’s Final PSM Standard
The final PSM standard was promulgated in 1992 and requires the employer to incorporate each of the 14 key elements in a formal PSM program. The key provision of final PSM standard is process hazard analysis (PHA)—a careful review of what could go wrong and what safeguards must be implemented to prevent releases of hazardous chemicals. Employers must identify those processes that pose the greatest risks and begin evaluating those first.
PSM clarifies the responsibilities of employers and contractors involved in work that affects or takes place near hazardous processes to ensure that the safety of both plant and contractor employees is considered.
The standard also mandates written operating procedures; employee training; pre-startup safety reviews; evaluation of mechanical integrity of critical equipment; and written procedures for managing change. PSM specifies a permit system for hot work; investigation of incidents involving releases or near misses of covered chemicals; emergency, action plans; compliance audits at least every three years; and trade secret protection.
Benefits of an Effective PSM Program
Effective PSM helps ensure the proper development of plant systems and procedures to prevent unwanted releases which may ignite and cause toxic impacts, local fires, or explosions in plants and installations.
PSM can also improve:
- the operability, productivity, stability, and quality of the outputs of hazardous chemical processes; and
- the design and specification of safeguards against undesirable events.
Effective PSM results in tangible benefits such as reduced exposure to lawsuits, OSHA penalties, public liability claims, and hikes in workers compensation insurance premiums.
Other intangible benefits include higher morale, increased trust, and an improved corporate image – the community sees the company as a responsible corporate citizen.
The final PSM standard mainly applies to manufacturing industries – particularly, those pertaining to chemicals, transportation equipment, and fabricated metal products. Other affected sectors include natural gas liquids; farm product warehousing; electric, gas, and sanitary services; and wholesale trade. It also applies to pyrotechnics and explosives manufacturers covered under other OSHA rules and has special provisions for contractors working in covered facilities.
The various lines of defense incorporated into the design and operation of the PSM process should be evaluated and strengthened to make sure they are effective at each level. Process safety management is the proactive identification, evaluation and mitigation or prevention of chemical releases that could occur as a result of failures in processes, procedures, or equipment.
What is a “process?”
To understand PSM and its requirements, employers and employees need to understand how OSHA uses the term “process” in PSM.
- Any group of vessels which are interconnected, and
- Separate vessels which are located such that a highly hazardous chemical could be involved in a potential release
For purposes of this definition, any group of vessels that are interconnected, and separate vessels located in a way that could involve a highly hazardous chemical in a potential release, are considered a single process.
What industries does PSM focus on?
The process safety management standard targets highly hazardous chemicals that have the potential to cause a catastrophic incident.
OSHA’s standard applies mainly to manufacturing industries–particularly those pertaining to chemicals, transportation equipment, and fabricated metal products.
Other affected sectors include those involved with:
- natural gas liquids
- farm product warehousing
- food processing
- electric, gas, and sanitary services
- wholesale trade
- pyrotechnics and explosives manufacturers
It has special provisions for contractors working in covered facilities.
Who is Not Covered by the PSM Standard?
The PSM standard does not apply to the following:
- retail facilities;
- oil or gas well drilling or servicing operations;
- normally unoccupied remote facilities;
- hydrocarbon fuels used solely for workplace consumption as a fuel (e.g. propane used for comfort heating, gasoline for vehicle refueling), if such fuels are not a part of a process containing another highly hazardous chemical covered by this standard; and
- flammable liquid stored in atmospheric tanks or transferred which are kept below their normal boiling point without benefit of chilling or refrigerating and are not connected to a process
To control these types of hazards, employers need to develop the necessary expertise, experience, judgment, and initiative within their work force to properly implement and maintain an effective process safety management program as envisioned in the OSHA PSM standard