Incident Response

Incident response is a crucial portion of environmental health. I personally have dealt with the repercussions of poorly done incident response due to an accidental discharge of environmentally toxic substances to a stream by a facility I was working at. It taught me how crucial it is that incident response be done correctly and thoroughly from start to finish, and begin before a release ever occurs.

Preparation is key in incident response. Any business needs not only a continuity plan, but an SWPCC (storm water pollution  prevention, and contamination control) and other environmental release plan. These plans should cover who to call, what methods of contamination to use, how to document everything that occurs from release to full cleanup, and how long the site should be under constant surveillance to ensure the release is fully contained and no more residual discharge occurs. Involving local entities like fire departments and police is important because you need to have them sign off on your emergency response plan before it can be validated and used. They need to sign off on it so that multiple departments don't all show up without knowing the location and what to do. That uses up valuable time, and also causes issues with the departments themselves because they have sent out many men to something that they may not have even been needed for.

During an incident, it is important to have an environmental specialist from your company on site overseeing the duties and activities of all those involved in the site response. He or she should be "CO" and direct all actions during the response. He or she should also be charged with documenting every individual who entered under his or her chain of command so that in the event that statements are needed from any individuals. Along with this, there should also be a protocol for entering and leaving the site so that all people are accounted for, and so that people crucial to the successful completion of the emergency response are nowhere to be found and difficult to contact.

Following the successful cleanup, full investigation should be done into the cause of the release or root of the problem. That may involve a facility wide audit, or shutdown of machines to have maintenance crews check them for leaks. It may call for a site evaluation from outside experts if your business is not staffed to handle a high level investigation. Regardless, it is something that needs to be done to prevent any future releases or discharges.

http://www.environment.nsw.gov.au/resources/legislation/201200227egpreppirmp.pdf

https://www.sepa.org.uk/media/100557/ppg-21-pollution-incident-response-planning.pdf

https://www.sydneywater.com.au/web/groups/publicwebcontent/documents/document/zgrf/mdq1/~edisp/dd_045259.pdf

AAI Rule and ASTM

When it comes to site evaluations for purchase and sale, there are multiple steps involved. One of these steps that you may not be aware of is the site evaluation under ASTM and EPA's AAI rule. These site evaluations are put in place to ensure the seller of the property has not done any harm to the environment that the buyer would have to fix, and also protects buyers from violations of the EPA's Clean Air Act, Clean Water Act, or Contaminate Land Management Act, just to name a few. The buyer is only protected from violations if they were unaware of the previous owner's transgressions of the acts, but also if they purchase a property and know about them, or there is sufficient evidence that they may be dealing with a site that needs some remediation, they need to act on it quickly to avoid punitive measures being taken against them.

The ASTM site evaluations come in 2 phases. Phase 1 is much more of a qualitative assessment. What a site investigator would do in the case of an ASTM Phase 1 site investigation is take a lot of pictures of the site from all angles. They would look for damage to the property, vandalism, and overall wear and tear. They would also look at distances from waterways, power lines, main roads, and other businesses or residences. This is important from an environmental standpoint because if the business is located right next to a stream or other body of water, more preventative measures will need to be taken by the owner of the property to ensure that no contamination enters the stream. Also, since there may be surrounding businesses and residences, it can be a high risk for the owner to operate a business that uses volatile substances or fine particulates. For example, a painting business for cars, bikes, trucks, etc. would be more likely to accidentally discharge paint spray dust among other particulates into the atmosphere because of poor air filtration and exhaust ventilation maintenance. The investigator will also look inside the facility at the general condition of the building, and will look to see if there are any processes that could lead to environmental contamination. During an ASTM Phase 1 site evaluation, things like lead paint, water and soil contamination, asbestos, molds, and other environmental and occupational hazards will be taken note of, but not tested until a Phase 2 site investigation.

An ASTM Phase 2 site investigation is the more qualitative portion of the site investigations done through ASTM. This investigation involves soil boring, water and air sample collecting, spore collecting and other field testing to check if the identified potential hazards in a Phase 1 truly are hazardous. It will also tell the potential  buyer if there is a history of dumping of toxic or environmentally harmful wastes on the site, if there has been any groundwater contamination that is likely, and even if there has been a major discharge of contaminated air since many of those particulates can settle to the ground around the facility.

The AAI Rule differs from ASTM in that it is a site evaluation standard directly from the EPA. The EPA AAI final rule is very similar to ASTM though. It borrows many of the same procedures as a phase 1 and phase 2 investigation, but it lumps them into 1 site evaluation. Also, since the EPA is the one who is investigating the site, they are able to go further into the records of the site owner to understand if they are innocent or guilty of violation of various codes and laws. This rule was under scrutiny that it was not thorough and stringent enough compared to ASTM to warrant the two being done by different organizations, but the EPA AAI Final Rule is being revised. If it is accepted, it will become the overall standard for site investigations nationwide.
https://www.epa.gov/sites/production/files/2014-08/documents/aai-reporting-fact-sheet-and-checklist-062111-final.pdf
http://www.epa.nsw.gov.au/clm/
http://dnr.wi.gov/files/pdf/pubs/am/am465.pdf

PortaCount Fit Testing

Fit testing is an important part of occupational hygiene and safety. Respirators come in various forms, shapes, and sizes, and ensuring a proper fit is integral to the safety of the respirator wearer. Often times, people who need to wear respirators have difficulty making a good seal on their face especially around the bridge of the nose. It is also incredibly difficult to accurately fit a respirator in an environment where constant communication is required. In this blog I will discuss the methods of respirator fit testing, the tests in a quantitative fit tests, and some types of respirators commonly used in industry.

Methods of Fit Testing:

Qualitative: This method is a basic form of fit testing. A user will put on a respirator of any design, and the tester will then run them through a series of simple yet thorough tests to make sure the fit is good. First, the user will instruct the user to place the respirator on their face with one strap going above the ears toward the top of the back of the head, and the other toward the base of the head. The tester will tell the user to make sure the seal around the nose is tight by pinching it and pressing it against the bridge of the nose. Then, the tester will ask the user to ensure a tight seal by placing their hand over the mask cartridges, or the mask itself (in the case of an N95 particulate dust mask) and breathe in. The tester will look to see if the sides of the mask suction to the face of the user, and if they do not, then the mask may be too big. Then, the tester will administer simple tests like asking the user to speak for approximately 1 minute and ask them after if the mask shifted during speech. They will ask the user to move their head in a full range of motion and ask again if the mask shifted. If the user thinks all is well with the mask, then the mask is likely to have a good seal. In the case of full face or half face cartridge respirators, the tester may also use a compound with a pungent odor to determine if the seal is good enough because if the odor reached the nostrils, it is likely that their is a breach in the seal.

Quantitative: This is a method of testing which supplies fit test values for various tests associated with overall respirator fit testing. The tests include: normal breathing, deep breathing, moving head side to side, moving head up and down, talking, grimacing, bending over, and finally normal breathing again. In order to accurately perform a fit test (I did this using a PortaCount Pro) you need to calibrate the machine to the ambient air by attaching a sampling train of a tube and a calibration filter and let the machine run through its calibration steps. Also, there is a cartridge in the machine that needs to be saturated with alcohol to ensure the machine runs properly. After that, the test subject must apply the mask and attach it to the sampling train attached to the test air (non ambient) side of the PortaCount Pro. Then the subject puts on the mask and runs through the tests. ANZI, OSHA, and NFPA (in the US) have different required fit factor values based on different mask styles and uses. The link to this table will show the specified values for each mask style.

Mask Styles: There are many mask styles. The 2 most important styles are ambient and supplied air. These are the 2 branches that every other mask style comes from. Some masks are full face, some are half face. Some are cartridge filtered (cartridges can be for chemicals, particulates, and other toxins) while others are directly supplied with oxygen. Even more basic are the N95 style particulate dust masks which you will often see contractors or carpenters wearing because they are exposed to wood and gypsum dusts regularly.

http://www.tsi.com/uploadedFiles/_Site_Root/Products/Literature/Application_Notes/ITI-046.pdf
https://www.osha.gov/video/respiratory_protection/fittesting_transcript.html
http://www.3m.com/3M/en_US/safety-centers-of-expertise-us/respiratory-protection/fit-testing/

OHSMS

OHSMS or Occupational Health and Safety Management Systems are designed to keep people within a business safe, people around a business safe, and the business afloat financially. They are designed with care and take countless hours of planning, but once they are in place, the rewards are tangible nearly immediately. You have probably worked in a business that has an OHSMS even if you were unaware or if they called it something else. Thinking back, I know I worked in a grocery store that had one because they had strict protocols and training required for employees in various departments of the business. For example, as a cashier, you had to understand repetitive stress injuries and the importance of breaks and stretching of the arms and fingers. As a stock worker, you had to be trained on slips, trips, and falls because of the nature in which the store stocked its excess products. Also, if I was to go into the freezer section, I had to be trained on the hazards of hypothermia, frost bite, and frost nip while also wearing the cold protective gear (big jacket, gloves, and a hat). All of these things are common in OHSMS which vary by site, and business as a whole.

The formal process of developing and OHSMS for any business is the same. It is a multi step process starting with identification of necessary safety protocols. Businesses can get these from incident or accident reports, loss evaluations, and even lawsuits. The purpose isn't just to keep people safe, it is to make sure that the business isn't hemorrhaging money. Therefore, even if there is only a slight risk or a small handful of incidents historically, but they cost exponentially more for the company to fix, those are areas that will more often be addressed as a priority due to the potential losses the company may endure.

Next, the process involves setting up formal policies to deal with employee health and safety. They can be simple policies that are as basic as, "Anyone entering the facility must check in at the guard shack and be administered full PPE before entering the plant floor," or they can be very complex. Usually, a safety policy is very blunt, and leaves nothing to interpretation because as an administrator, you do not want people taking liberty with the policy due to excess grey areas.

Following the formation of policies, the OHSMS must review those policies to ensure they are doing exactly what they were designed to do. For example, if a policy on requiring all employees to wear steel toed shoes is developed, but the number of crush injuries to the foot does not decrease, a more stringent policy addendum should be made. Perhaps the steel toed shoes are not rated to the proper specifications required in the plant, or maybe the crushes happen on the metatarsals instead of the toes.

In addition to auditing the policy, it must be enforced. Using the safety shoe example again, if the policy requires employees to wear safety shoes, but nobody does or they take liberty with the policy, supervisors need to follow-up with disciplinary actions. This seems harsh, but it is the reasoning behind why people get speeding tickets. Personally, if I knew I would never get a ticket for speeding, I would drive as fast as I felt comfortable doing. Just like speeding, violation of safety policies put you and others at risk of serious injury and even death.

Lastly, the process needs to be audited on a consistent basis. This can be annually, bi-annually, or even every day if it is feasible to do so. Whatever the time frame is, it needs to be done thoroughly and by competent people so that critical areas of improvement are identified. Audits should also be done by people who are impartial to the groups involved in the audit. This is often why corporate offices often have audit teams that travel to various locations where they have little to no personal connection with the individuals there.

http://www.education.vic.gov.au/Documents/school/principals/management/ohsmsguide.pdf 
https://www.worksafe.qld.gov.au/__.../safety-mngt-sys-audit-report.doc
http://www.worksafe.vic.gov.au/safety-and-prevention/health-and-safety-topics/ohs-management-systems/ohsms-audit-tools

ISO Standards 9001, 14001, and OHSAS 18001

ISO and OHSAS standards are not required by any industry, nor are they legally enforceable, but they are important standards for many businesses. ISO, the acronym for the International Standards Organization while OHSAS is the acronym for "Occupational Health and Safety Advisory Services." These 2 organizations are crucial to the success and longevity of many businesses nowadays and many businesses strive for certification in ISO 9001 and 14001, as well as OHSAS 18001.

Since ISO is an international organization and thousands of businesses operate under ISO certifications, it is nearly a requirement for a business to get at least 9001 quality certified to have a stake in any international market or develop business relationships with international clients. This is because having and keeping any ISO certification shows a dedication to whatever the certification is for. In the case of 9001, it shows a dedication to the manufacture of a quality good which is important if you want to sell your goods to other businesses. Even if you have an incredibly low price, it is still unlikely that you make any international sales if you do not have 9001 certification.

As for 14001, this certification or standard is related to environmental sustainability and protection. It is a certification that is becoming increasingly popular in recent years, and many businesses are making it a standard for all of their branches to achieve. I have personally worked at achieving ISO 14001 certification, but it is a long and arduous process, especially if a business does not have a strong environmental protection, or sustainability program in place. Some of the major parts of ISO 14001 that make it different from 9001 are that for ISO 14001, a team of people responsible for Environmental Health and Safety will usually lead and develop the program. In ISO 9001, quality engineers and operations manager-like professionals will develop that program. Every quarter, ISO 14001 significant aspects and impacts on sustainability must be audited and reviewed to ensure they are steadily approaching completion. In the long run, the goal of ISO 14001 is for businesses to end up giving back as much or more to the community and environment than they take away.

OHSAS 18001 is slightly different from the ISO standards but is still important. It is far less utilized formally at this point than either ISO 9001 or 14001 because there is no clear benefit for businesses interested in making sales or doing international business. However, just as ISO 14001 was slow to start, OHSAS 18001 could make a significant impact on the way businesses overseas in third world countries approach the issues revolving around employee health and safety. As you may know, third world countries have little to no safety concerns for their employees and serious injuries and death often occur from poor working conditions. In the US, and EU, it is highly unlikely that a business couldn't put together a formal OHSAS program and achieve certification due to the fact that OSHA and OSHA-like organizations require (by law) businesses to do many things that would fall under the OHSAS 18001 certification program.

The process of getting certified for any of the 3 of these aforementioned programs is very similar. There must be identified significant impacts to the business, environment, or safety of employees. Next, these impacts must be pursued by a team or individual on a specific time frame not to exceed 1 year. Then, the processes must be audited to ensure that what was suggested s actually being done, and the results of those audits are brought up in management reviews to keep upper management informed. Also, policy updates are required and other clerical work such as form retention policies must be abided by.

http://www.ohsas-18001-occupational-health-and-safety.com/
http://www.iso.org/iso/home/standards/management-standards/iso_9000.htm
http://www.iso.org/iso/home/standards/management-standards/iso14000.htm

OSHA Process Safety Management Standard

Process Safety Management is an important way to ensure that all aspects of any job, and all people withing an organization are kept safe. To help facilitate this, OSHA has developed the " Process Safety Management of Highly Hazardous Chemicals standard (29 CFR 1910.119), which contains requirements for the management of hazards associated with processes using highly hazardous chemicals." This standard is enforced across all businesses involved or categorized under general industry (excluding construction) and is an integral part of any business, especially those who are involved in the chemical manufacture trade.

Under 29 CFR 1910.119, the employer is required to control all materials that are highly flammable, reactive (corrosive), explosive, or toxic. The exceptions of this rule are facilities used for retail, and oil well drilling facilities. Gasoline, propane, and other hydrocarbon fuel sources are exempt from the regulation if the quantity stored is under 10000 lb, and they are not mixed with another flammable, reactive, toxic, or explosive material.

To actively engage in the use of this program, the facility must be inspected regularly by a team, and also, any incoming products must be examined by a member of the team who is deemed competent in the field of materials science or engineering. "Analysis shall be performed by a team with expertise in engineering and process operations," describes the qualifications of the people that must be on the team. As you can see, the team must be a technically skilled team so that hazards are accurately identified. One member of the team must also be fully capable of understanding how to effectively control the hazards of any identified problem areas in the facility.

Along with inspecting does come controlling. As we know from EHS methods of control, the best way to control an issue is through engineering. Engineering can be costly, but if it is feasible, OSHA requires it to be done over any other form of control. One example of how to use engineering to control a problem would simply be to purchase and use fire safe, and corrosion safe containers for materials that are explosive, reactive, and flammable. On top of this, administrative controls can be used to put in place formal procedures for the use and storage of any materials that enter the facility. By making these policies or rules, the company is not only controlling the hazard, but also documenting the methods and manner in which the workplace is expected to operate which can lead to further documentation if there are transgressions of the policy. Finally, PPE can be used as well to cover the "trifecta of hazard control options" by providing and requiring employees to use a specific type of glove, like PVC, when working with reactive materials.

Process safety management is also used to control exposure if there in an unfortunate exposure or failure of the system. It covers protocols for exactly what to do in the event of a release, or exposure. It covers where to take an exposed person, and will provide doctors with all the pertinent information they will need to effectively treat the patient. It also covers who to contact and how/why/when to contact them in the event that the release becomes a larger issue other than environmental cleanup. For example, this program can prevent accidental environmental discharge by containing a spill to a localized area, and getting experts to the site to remedy the situation.

All in all, process safety management is important and often required for many businesses. Utilizing it may be difficult at times, but in the long run, it can save lives and thousands of dollars in damages and settlements.

https://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=STANDARDS&p_id=9760

https://www.osha.gov/Publications/osha3133.html

https://www.osha.gov/pls/oshaweb/owasrch.search_form?p_doc_type=INTERPRETATIONS&p_toc_level=3&p_keyvalue=1910.119&p_status=CURRENT

Tert-butyllithium

To ensure that when shipping any substance, the potentially exposed are aware of what exactly is being shipped, proper documentation, labeling, packaging, and transport methods must be followed. In this blog I will describe how to effectively safely ship 25mL of tert-butyllithium in heptane.

The Department of Transportation has the responsibility of making sure that all materials shipped are done so according to strict standards, especially when it comes to the shipment of biological and hazardous materials. To abide by the regulations for shipment of hazardous materials, there are seven steps to follow when preparing these types of materials for transport. The steps are:
1- Classify the material and name it
2- Properly package the material
3- Mark the parcel with pertinent information
4- Label it with the proper safety information
5- Complete and attach the necessary paperwork (cradle to grave)
6- Place the proper placards and stamps on the package
7- Place the material in the proper transport vehicle and place the same placards on the vehicle

In step 1, according to the data sheet for TBL, you would classify it as a "pyrophoric, liquid, water reactive, organometallic substance." You would also put the UN number 3394 and  reference #'s 4.2 and 4.3 on the name and information label and sheet that you will later include in the package.

As for packaging, since the substance is 25 mL, you can use a waterproof sealed 125 mL test tube labeled with the name and UN number of TBL. Then, the test tube would be placed inside an airtight casing to protect it further and place that with some form of foam or padded insulation in a rigid cardboard box.

The box before it is closed will have a hazardous substance manifest included in it, and the SDS sheet for TBL along with the manufacturers paperwork including the name, toxicity, and hazardous information as well as emergency contact information that is direct from the manufacturer.

The parcel will then be marked with the labels for corrosive and reactive materials using the numbers 4.2 and 4.3 on the package. The labels will be placed within 6 inches of each other and not cover up any other markings on the package. The package will also be marked with the name of the material along with the labels "Dangerous When Wet" and "Spontaneously Combustible" in clear, easily noticed lettering on the front of the package, but not covering any other markings.

At this point, the paperwork is mostly duplicates of what is already done for the internal packaging, but the attached paperwork must be placed in a waterproof sleeve on the package. It must include the name, UN number, hazard class, quantity, destination, name, and emergency contact information. This is for responders who need to know what exactly to do with the material in the event of an accident or other misstep that can cause a reasonable leak within the package.

The last step involves perparing the shipment vehicle, and since TBL is not permitted to be shipped via plane, it must be shipped by ground, or sea. I choose to ship this by ground via railway because I am shipping it to Hartford, CT. For this method, I must change the placards on the train car to mimic the ones on the package. The placards will show the UN number of TBL (3394) and the hazard class of 4.2 and 4.3.

By following all of these instructions, I can say that I will be able to safely and legally transport 25mL of tert-butyllithium to Hartford, CT from Athens, OH. If it takes 2 days to arrive in CT i can expect that if the train is kept at 15 degrees celsius, that 24.995 mL of true TBL will arrive due to its decomposition rate of 0.02% weight per day at 15 degrees C.

http://www.fmclithium.com/Portals/FMCLithium/content/docs/DataSheet/QS-PDS-044%20r2.pdf

http://131.104.156.23/lectures/7113/7113_Literature/FMC%20Lithium%20pdf/FMC_ButylCat_web.pdf

https://www.fmcsa.dot.gov/regulations/hazardous-materials/how-comply-federal-hazardous-materials-regulations

LA Gas Leak

In February, SoCalGas was responsible for a massive gas leak that has affected the lives of thousands of LA residents, and has adversely impacted the entire state. The gas leak was from one of the drilling/pumping locations outside of Los Angeles, and the site is nearly half a century old. The leak was caused partly because the management team decided that the cost vs. risk of not reinstalling a secondary release cap was not worth the time or money required to do the job effectively. Essentially, they put company money and time as a higher priority than the environment, and the people of the state. 

One may ask why the company would ever do this. Well, risk and cost benefit analysis, also known as CBA, are both huge parts of any company. No major project is ever initiated without a thorough cost benefit analysis. It weighs all aspects of the project from initiation to completion on a scale using dollar values to often represent not only the actual costs of doing the project, but the potential for humans, animals, and other wildlife to be harmed. For example, if a human is harmed because of Project X, then a company will say that compensation will equal let's say 100,000 U.S dollars. If the project is expected to make the company 1,000,000 US dollars per year and is expected to last 25 years, then it means that in order to make the project economically feasible, it cannot cause harm to any more than 250 people (1,000,000 x 25 = 250 x 100,000). However, many other factors go into the process.

In the case of SoCalGas, the risk management team decided to go away from re-installing a secondary containment cap because it was going to be a lengthy and difficult process. This is all fair in business as it is very common to make that justification and decision. However, "upkeep on the initial well cap was either poorly documented or ignored" because there was no effort to replace or fix the cap after the decision was made in the 1980's. That means that for over 30 years, the initial well cap was not fixed. The result was a gas leak of methane that dispensed over 1/4th of the entire state's annual average carbon emissions to the atmosphere in a matter of days, and nothing could be done about it to stop it immediately.

Also, since the leak consisted of pure methane, and the release occurred during very mild winter months, there was plenty of excess sunlight to convert the methane to methanal, also known as formaldehyde. Formaldehyde, as you may be aware, is an embalming fluid that is toxic to humans and may even cause cancerous growth within soft tissues of the body. With vaporized, or gaseous, "formaldehyde being converted through oxidation being just barely heavier than air, it can mix in with atmospheric gases" and enter the body easily through inhalation. the respiratory pathways are incredibly vulnerable tissues because the "lungs and alveoli can become saturated" with the gaseous formaldehyde and it may never escape because it, again, is heavier than oxygen. 

All these things considered, the CBA of not reinstalling the secondary cap overlooked many of the disastrous outcomes. Children have been evacuated from schools and essentially quarantined in their homes. Countless people are unwillingly exposed to potentially toxic chemicals. SoCalGas is undoubtedly dealing with a PR nightmare and extensive costs to fix their mess. All in all, it is important to always think of the worst before making a decision that can put thousands of unwilling, unknowing people at risk.

http://enenews.com/experts-formaldehyde-spewing-massive-la-gas-blowout-body-start-digesting-very-dangerous-methane-basically-turning-embalming-fluid-officials-be-warning-theyre-dont-about-video

http://scorecard.goodguide.com/chemical-profiles/html/formaldehyde.html

http://www.olemiss.edu/courses/bisc207/respiration.html

Understanding the Importance of Physical and Chemical Properties

All substances possess various physical and chemical properties. Physical properties can be the mass, density, flammability, explosive nature, and even radioactivity of a substance. Chemical properties can be related to the incompatibility or compatibility with other substances through their reactivity. Common reactions include addition and reduction, but can be much more complex. Many products of chemical reactions can be harmful to human health and that of the environment which is why it is important to understand all aspects of a chemical or substance's physical and chemical properties before using it or disposing of it.

For example, many solvents like isopropyl alcohol are highly flammable and should be stored in containers that are fireproof. Large quantities in drums should be stored in a room that keeps the drums protected from the elements, and the drums should be grounded to direct static or other forms of electrical charge away from the containers so that the material inside does not ignite.

Also, cans that hold contents under pressure are of high concern when dealing with storage environments. All cans containing substances that vaporize at low temperatures (lower than ambient air temperature) should be stored in temperature and climate controlled environments. This is because if the temperature gets too high, the contents of the container will rapidly vaporize and condense throughout the course of the day if it gets hot and cold. This weakens the integrity of the storage container and can cause it to crack or rupture and the material inside will then escape either as a gas, liquid, or semisolid. Even if the container does not undergo this variety of stress, if it is stored in an environment that is simply too hot and causes the material within to vaporize, it can cause an explosion of the container which is highly dangerous. Hazards such as this, as I have stated, are common with highly volatile substances such as solvents.

In the event that a container for a gas or liquid does rupture, the physical hazards can compile on themselves. First you have the initial hazard regarding the rupture of the container and release of the substance within. If nobody is harmed by the rupturing process, the exposure to gases can cause serious physical harm by asphyxiation, or even contact. In the event that a heavier than air gas like propane is discharged in high volumes to a confined space, it will displace all oxygen and the people within that space my suffocate or at least pass out from lack of oxygen in the lungs. If the container held a reactive acid, the physical hazards can be severe in that they can lead to chemical burns, and also through chemical reactivity, heat can be generated which, if not dissipated, can cause heat stress in a small, localized environment.

On the subject of reactivity, if an acid that is not contained properly leaks into a storage unit, or even onto the floor of a facility, sometimes drastic consequences can arise. In the case of sulfuric acid mixed with water, incredible amounts of heat arise. Also, if some amounts of fluorine react with water, you can get hydrofluoric acid which can chew its way through a plethora of materials, including human skin in a matter of seconds.

The best way to protect yourself and your company is to thoroughly understand the physical and chemical properties of substances and materials so that you can properly store, use, and dispose of them without causing harm.

http://chemed.chem.purdue.edu/genchem/topicreview/bp/ch11/acidbase.php
http://antoine.frostburg.edu/chem/senese/101/thermo/faq/always-add-acid.shtml
http://environmentalchemistry.com/yogi/hazmat/articles/explosives.html