The Language of EHS Part II: Air

Continuing with my take on the EHS lexicon, let's talk about one of the more ubiquitous and unwieldy parts of the EHS regulatory arena: Air. Whether you're talking about environmental or safety, air quality is an issue that is going to come up, and it can get sticky. How are the contaminant emissions from the facility stacks impacting the local community? And 'closer to home' how is air quality within the facility impacting worker safety and productivity?

These are the kinds of questions that are at the heart of the air arena. Of course, the regulations that have been constructed around these two questions sometimes get just a wee bit off course, but that's part and parcel to our command and control regulatory structure here in the US. But I digress.

Let's explore some of the language of air in the EHS world.

CAA: Clean Air Act. This was the legislation that would forever create the regulatory structure for air quality under which US companies currently struggle. The enacting regulations are lengthy and convoluted (like many environmental regs) and for any company that employs contaminant-emitting processes, this likely represent the biggest time-eater for their environmental staff.

Title V: refers to Title V of the CAA as amended in 1990. This resulted in the creation of a new operating permit structure for 'major sources' of air emissions. Under this structure, a source is major if it emits more than the threshold of any of the criteria pollutants. If a facility is a major source, it is required to obtain a Title V operating permit.

Ok, I just re-read that definition, and it spouts lingo left and right, here are some of the related definitions, to help clarify.

Let's start with the NAAQS: National Ambient Air Quality Standards. Ambient Air Quality standards, or criteria, are set for six common, or 'criteria pollutants:' Ozone, Particulate Matter, Carbon Monoxide, Nitrogen Oxides, Sulfur Dioxide, and Lead. The criteria are not stagnant, and change periodically. When they do, it throws everyone into a tizzy because it impacts what areas of the country are designated 'attainment' versus 'non-attainment' for the pollutant in question.

Attainment/Non-attainment is basically an evaluation of the air quality of an area (in Ohio, areas are designated attainment/non-attainment on a county by county basis, for the most part, other states may vary) against the criteria for the pollutant in question. If an area is 'attainment' for a pollutant it means that the area, on average, meets the NAAQS criteria for that pollutant. The states had to set up a huge network of monitoring stations in order to monitor for the criteria pollutants, and it is based on this data that designations are made.

When a new NAAQS standard is released, USEPA includes a deadline for each state to recommend designations within its boundaries. The state environmental regulatory agency evaluates all available monitoring data, and makes recommendations to the USEPA, with supporting evidence, for the designation of each area as either attainment or non-attainment for the new criteria. USEPA then reviews the information provided, and either agrees (making the designation 'official') or disagrees, and counters. This process is lengthy, and can lead to some back and forth between the state agency and the Feds.

It makes a BIG difference how an area is designated, because it impacts the definition of 'major source' as well as what type of permit a major source must pursue when installing a new emitting unit (or a new facility, for that matter). Companies have been known to locate plants based on the existing designation of an area, and this can be a huge consideration for new installations. As a result, NAAQS designation can have a profound impact on the economy of an area, particularly in heavily industrialized regions. I'm from Ohio. I know from whence I speak here. Economic impact has become a huge issue between OEPA and the Feds for precisely this reason.

Alright, again, I barely scratched the surface of the environmental regulations realted to air quality, but I really want to get into the safety regulations, because it's an important topic. indoor air quality (IAQ) in a facility is essential to worker health and safety, and is something that can generally be managed through installation and maintenance of appropriate ventilation equipment.

OSHA has published data on what they consider 'adequate' air quality for various chemicals and pollutants. There is a whole bunch of acronyms that go along with understanding this regulatory realm, and what 'limits' an employer should evaluate against is something I've heard debated more than once. Let's start with the OSHA 'official' limits, and then we'll discuss other sources that you should review.

PEL: Permissible Exposure Limits - OSHA has established over 500 PELs, mostly within 29 CFR 1910.1000 Table Z-1. These are regulatorily-required limits related to air quality within workers' breathing zones (also referred to as BZ). PELs are set mostly as 8-hour TWA or time-weighted average, limits. For evaluating this limit, air quality is measured continuously over a typical 8-hour shift, and the average exposure must be below the TWA limit. There are also PEL-STELs or short-term exposure limits, usually 15-minutes. For evaluation purposes, the continuous measurements are averaged in 15-minute increments, and for no 15-minute period may the STEL go above the limit, even if the TWA is below the limit. Some chemicals may even have a PEL-C, or ceiling limit established, which is an exposure limit over which a worker should NEVER be exposed.

NIOSH: the National Institute of Occupational Safety and Health is part of the Center for Disease Control & Prevention (CDC). This agency is responsible for conducting research and making recommendations on the prevention of workplace injuries and illnesses, and as part of that directive publishes the NIOSH Pocket Guide to Chemical Hazards (NPG). The NPG is updated far more frequently then the OSHA PELs. The 2005 NPG contains general industrial occupational exposure limits for 677 chemicals. The NIOSH limits, referred to as RELs (Recommended Exposure Limit), follow terminology analogous to that used by OSHA, with TWA, ST and C limits. The NPG is particularly useful, because it also provide a lot of other data on the chemical, such as its chemical properties, exposure routes, symptoms of exposure, etc. As a bonus, the entire guide is available on line, or in a downloadable format from the CDC. However, NIOSH is NOT a regulatory body, and can only make recommendations regarding exposure limits. These limits do not carry the force of law, though OSHA has been known to enforce them under the General Duty Clause.

ACGIH: American Conference of Governmental Industrial Hygienists (though I notice on their web page that they have dropped the 'governmental' part of the acronym, which I find curious). ACGIH also publishes their own set of occupational exposure limits. ACGIH is an entirely independent body, not related to the government. Their exposure limits, called TLVs or Threshold Limit Values, are developed by a body of independent IHs (Industrial Hygienists). There have been instances where the science behind thier limits has been questioned, and I am, by no means suggesting that you blindly accept the limits ACGIH publishes. However, though OSHA does not generally enforce these limits, it is always good to be aware of them. ACGIH is often at the leading edge of limit setting for occupational exposures, and if they choose to make a stink about a particular chemical, NIOSH and OSHA usually at least lend an ear, if not a hammer.

General Duty Clause: I realized, looking over the above, that I threw out a term that you hear bandied around in the OSHA realm a lot, and there's a good reason for it. The General Duty Clause is a catchall in the OSH Act of 1970, and states in part that "Each employer shall furnish . . . a place of employment which [is] free from recognized hazards that are causing or are likely to cause death or serious physical harm . . ." As an employer, therefore, it is not enough to comply with the OSHA standards, but you must take action to abate any and all recognized hazards. That is why it is important to be aware of what NIOSH and ACGIH have published as limits. Though fairly recent court rulings have put the brakes on OSHA issuing citations against NIOSH or ACGIH limits, note that states can, and often do adopt more stringent limits then OSHA (Particularly California, where CalOSH has been known to adopt ACGIH limits as law).

It is in every company's best interest to periodically test the air quality within their facility. Developing a routine Air Quality Evaluation protocol. Physical testing should be conducted at least once every couple years, or when there is a change in the facility operations. If your company is a small business, the state BWC (Bureau of Workers Compansation) will often offer help. I know in Ohio, at least at one point in time, BWC would actually come in and perform the testing for a small company, and provide the results with a preliminary evaluation. There are also consulting firms that offer this sort of testing, and can also provide aid for taking corrective measures where problems are found.

The key when designing any new industrial process is to ensure that proper ventilation and other safety measures are included in the design requirements up front to avoid the development of problems once the process goes into operation. However, as with any new process, it is important to test to ensure that everything is working as designed.

In addition, tracking results over time, and under different operating scenarios (summer versus winter, for example) can also help reveal conditions under which worker safety and health may be compromised, even with appropriate controls in place. Air quality is influenced by so many factors, that a one-time testing under controlled conditions is not enough to provide a clear picutre of the exposures a worker may experience.

I got a bit off-topic there toward the end. I will be back next week with the next installment of my take on the EHS lexicon. Again, if you have any particular areas you'd like covered, leave a comment and let me know.