Section 4: Appendices
To design and maintain a safe facility taking such steps as are necessary to prevent
releases:
Failure to design and maintain a safe facility. In determining this factor, the case team should
consider the conditions at the facility, applicable design codes, federal and state regulations,
recognized industry practices and/or consensus standards.
10
Failure to provide for sufficient layers of protection. An additional layer of protection would
have prevented the release or explosion.
Failure to update design codes.
Failure to implement a quality control program to ensure that components and materials meet
design specifications and to construct the process equipment as designed.
10
Design failures include, but are not limited to failure to adhere to applicable design codes and/or industry
guidelines, including advisory standards. Examples include: API (American Petroleum Institute) standards; ASME
(American Society of Mechanical Engineers) standards; ANSI (American National Standards Institute) standards;
NFPA (National Fire Protection Association) guidelines; NACE (National Association of Corrosion Engineers)
standards; AIChE (American Institute of Chemical Engineers) guidelines; ISA (Instrument Society of America)
standards; International Fire Code.
Design failures also include failures to adhere to consensus standards which may also include manufacturer’s
procedures. An example of an industry consensus standard is a manufacturer’s product safety bulletin, the Material
Safety Data Sheet, or other publication which outlines safe handling and processing procedures for a specific
chemical or substance. Many of these publications discuss materials of construction, safety equipment, tank design,
and which API or ANSI standards to apply to the handling of that specific chemical or substance.
Other design failures include common sense design flaws or inadequate equipment such as failure to include
sufficient instrumentation to monitor temperature, pressure, flow, pH level, etc. Other design flaws include lack of
emergency shutdown systems, overflow controls, instrumentation interlocks and use of failsafe design. For
example, operators should typically design steam vent valves so that, if they fail, they will fail to a safe part of the
plant and not a part of plant where there is material in process. Instrumentation is vital for any process including
foods processing as well as industrial and petrochemicals. This is especially important in vessels and tank reactors
which handle polymers. Such chemicals have the potential for runaway reactions. It is important to have
automated systems to detect high levels of chemical vapors and alert the appropriate facility personnel/authorities
that a release may be occurring from a process. Such monitors and alarms should be placed in the appropriate
locations.
Maintenance failures would include failures to maintain tanks, piping, instrumentation, valves and fittings, such as
the isolation valves on tanks, or the steam shutoff valves and level switches and gauges. Such failures have
historically contributed to major catastrophic releases and/or explosions. For storage facilities, considerations must
be made for incompatible chemicals, spillage, tank/container integrity, appropriate secondary containment,
appropriate temperature conditions for storage, building code compliance, adequate aisle space for emergency
responders and forklifts, cut off storage, fire protection systems, etc.
25