guide based on answers to the following
• Is there an evacuation?
• Is product on the ground?
• Is there a fire?
• Are there reports of injuries?
• Is the area populated?
• Are sensitive receptors (e.g., hospitals,
day cares, nursing homes, schools)
• Are there impacts to water supplies?
• Does the facility have a history of releases?
• Does the release have a high potential
to disrupt commerce?
information must originate from a credible source and be expressed in lay terms.
Environmental Chemical Releases
Proper monitoring must be implemented
quickly in all affected environmental
media, adjusted to meet changing conditions, and performed constantly for the
duration of the release, both to protect
workers and offsite receptors and to generate complete documentation of the incident. Responses to airborne releases
should include 360-degree perimeter and
community monitoring at locations of
interest (e.g., exclusion zone perimeters,
schools, nursing homes, residential
areas) and at the breathing zone to represent human exposures.
If the facility does not have monitoring resources, skilled third-party environmental monitoring teams are necessary.
Extensive knowledge of monitoring and
sampling methodology, the capabilities
and limitations of monitoring equipment,
and the proper documentation of equipment maintenance and calibration are essential to collect sound data. Air
dispersion modeling may also help predict the extent of chemical plume movement and the resulting concentrations.
Special to the Digital Edition
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a special section, unavailable in print,
on pre- and post-emergency response.
Look for the digital edition to reach
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the best first response. However, PPE may
have its own hazards and limitations (e.g.,
restricted motion, limited line of sight,
and physiological stresses), so quick data
collection is necessary to place workers in
the most appropriate PPE.
In our experience, if the answer to
some or all of these questions is “yes,”
the public will view the incident as significant—even if the chemical has relatively benign toxicological properties.
Human Health Hazards
Because of the urgent need for health
hazard information, industrial hygienists
must have access to useful information
about chemicals’ effects on human and
environmental health. Toxicology support personnel should be intimately involved with identifying the chemicals,
summarizing toxicological data (e.g.,
dose-response data, epidemiological
studies), and determining the routes of
exposure that pose the greatest risk to
workers and the community. This information is also necessary for proper hazard communication, and not only with
onsite responders. Local medical facilities
need to be briefed on decontamination
issues (e.g., do exposed persons pose a
secondary contamination risk to health-care workers?) and chemical hazards.
MSDS are often used to communicate
health hazard information to treating
physicians, the public, and first responders. We do not agree with this practice.
While we use MSDS to identify the product and percent composition of chemicals and physical chemical properties, we
rely on more appropriate sources of
health hazard information for dissemination to the public or emergency room
physicians, including the Agency for
Toxic Substances and Disease Registry
(ATSDR) Medical Management Guidelines, the documentation of TLVs®,
AIHA® ERPGs, and Acute Exposure
Guidelines levels (AEGLs). The scientific
Exposure Guidelines and Action
Responders must also identify protective
action levels. For example, responders
might enact an action level that is one-half of the appropriate occupational exposure limit (OEL) so that changing
conditions identified through environmental monitoring can lead to appropriate actions before the OEL is exceeded.
Hazard mitigation activities can cause
rapid changes in chemical concentrations in work areas, which could require
an upgrade of worker protection. Responders must also develop community
action levels to help determine the extent of evacuation areas.
Personal Protective Equipment (PPE)
Responders must identify the proper PPE
for workers involved in hazard mitigation
and cleanup. Frequent re-evaluation of
environmental conditions is necessary to
make informed decisions about upgrading
or downgrading PPE. When environmental conditions are unknown, or when initial monitoring data is still being
acquired, the most protective PPE is often
Operational Approaches to Hazard
Responders must be able to identify
proper responses to chemical releases as
they occur and if there is reasonable anticipation of explosion, fire, or failure of
chemical containment mechanisms. Also
important is the placement of proper
chemical containment and decontamination equipment for limiting contamination to the exclusion zone.
As conditions change and/or mitigation
progresses, the approach to hazard mitigation must change accordingly. For example, dealing with a chemical fire poses
new challenges. Should responders fight
the fire, or allow it to burn? Fire hazards,
including smoke and vapor exposures,
change when the fire is controlled; in
post-fire cleanup operations, workers face
structural hazards and the potential for
dermal exposure to surface contamination.
Response leaders must be able to adjust
plans quickly and appropriately to respond to the change in conditions.
Another consideration is the accumulation of hazardous waste from mitigation activities. Facilities must be
prepared to identify hazardous waste,
quickly handle waste collection and
storage prior to removal and disposal,
and ensure that workers involved in
cleanup are properly certified and
trained for hazardous waste work.
Glenn C. Millner, PhD, is founding partner and principal toxicologist with the Center for Toxicology and