Frequently Asked Questions


What are the consequences of not meeting OSHA regulations?

Failure to comply with OSHA regulations can lead to serious fines and legal problems. OSHA has a standard procedure for discovering violations and for treating violators.

If an OSHA inspector finds a violation, the agency issues a citation and proposes a penalty. The citation must be specific and detailed, and the proposed penalty will have a deadline. Along with a penalty comes a list of actions a violator must take to correct the situation. Penalties are scaled to the severity of the violation, which are labeled in different categories: “willful, serious, other-than-serious, de minimis (trivial), failure to abate, and repeated.”

As of January 2017, most fines are $12,675 per violation. A company failing to correct a problem could also be fined $12,675 per day. Companies showing a “willful or repeated” pattern could be fined $126,749 per violation. These are obviously nontrivial amounts.

To help companies navigate the enforcement policies of OSHA, the agency provides compliance assistance specialists in most of its area offices. These can be found here.

Companies have the chance to appeal any citations. These appeals are made to the OSHA Area Director and can address the citation, penalty, abatement dates or other details. Companies have 15 working days after receiving a citation to file an appeal.

general info:

How are OSHA regulations enforced?

OSHA oversees roughly seven million workplaces in the U.S., so the agency must prioritize when it conducts inspections. “Imminent danger situations” and cases of severe injuries and illnesses are the first priority. Next are cases resulting from worker complaints and referrals. Next, targeted inspections look at high-hazard industries and individual workplaces that have a record of noncompliance. Lastly, follow-up inspections are sometimes done to check on abatement.

Inspections are done without advance notice but according to a published, standard procedure. They begin with a presentation of credentials and a conference with the employer. The walkaround is conducted with a representative of the employer as well as an authorized representative of employees, if requested. The compliance officer can also talk to employees in private during the inspection.

Inspections end with a closing conference to discuss findings. If there are violations, employers can discuss possible courses of action as well as ways to contest any citations and penalties.

OSHA enforces many different rules regarding workplace safety, not just air quality standards. Its compliance officers are trained to examine all of these areas, and employers can expect inspections to address all of them. Still, violations of air quality regulations are the fourth most common citation, after fall protection, hazard communication, and scaffolding problems.

Citations can lead to serious fines. As of January 2017, fines are $12,675 per violation, which can add up if there are multiple offenses. Companies showing a “willful or repeated” pattern could be fined $126,749 per violation.

OSHA provides assistance in navigating the enforcement process. Their compliance specialists are available in most of their area offices. Appeals can be made up to 15 work days after receiving a citation. OSHA maintains that their priority is maintaining safe workplaces and not pursuing citations.

What is a PEL?

The Occupational Safety and Health Administration (OSHA) bases its air quality standards on “permissible exposure limits,” or PEL’s. A PEL is a maximum amount of substance in the air that a worker can be exposed to over the course of an eight-hour shift. The exposure is measured as a time-weighted average (TWA). If an exposure goes over the PEL, penalties can ensue.

Adhering to PELs is important for many reasons. First, workers’ health depends on it. PEL’s are set based on evidence of health effects, and they represent the maximum safe exposure. In fact, OSHA has said that many of today’s PEL’s might be outdated. Many of OSHA’s PEL’s were set in the early days of the agency, and it is possible that stricter limits are needed to adequately protect workers. The agency advises that employers err on the side of caution when setting air quality goals. Here are PEL’s for some common industrial contaminants:

  • Cadmium: 0.005 mg/m3
  • Hexavalent chromium: 0.005 mg/m3
  • Lead: 0.05 mg/m3
  • Nickel: 1.0 mg/m3
  • Manganese: 5.0 mg/m3

How do I make sure I am meeting OSHA PEL’s?

The first step in meeting a PEL is to understand your current air quality. Doing an air quality audit allows you to get a comprehensive, quantitative analysis of your air quality. Independent, licensed, third party professionals—usually industrial hygienists—perform this service by setting up monitors throughout your facility to collect and analyze air quality data. They can also attach monitors to workers’ uniforms to test exposure in the breathing zone. An air quality audit collects information on the volume of contaminants, toxicity and when and where air quality problems are occurring. An audit comes with a full report which can be a very useful tool in creating an air quality strategy—or in documenting the exceptional air quality you might already have!

If your air quality exceeds the PEL for any of the substances OSHA regulates, there are solutions. Increasing ventilation can cut contaminants and lower workers’ exposure levels. Adding ambient filtration would also achieve this goal while avoiding the high energy costs associated with ventilation’s need for heating or cooling your makeup air. If a more intensive solution is needed, a source capture system could be installed where the fumes or dust are generated. Source capture is the most efficient means of reducing exposure levels and meeting OSHA PEL’s. You can learn more about these options here.

The air quality experts at RoboVent understand how to meet any air quality goal in the most cost-effective way possible. They discuss with you the variables involved—airflow, filter media, targeted substances, equipment location and more—and prescribe solutions. They understand regulations and PEL’s as well as they do blower speeds and filter types.

What is a TWA?

A TWA is a time-weighted average and relates to a worker’s exposure to harmful substances. The Occupational Safety and Health Administration (OSHA) sets their permissible exposure limits (PEL’s) as TWA’s. In short, a worker’s exposure level is averaged over a certain time period—usually a typical eight-hour shift during a 40-hour workweek.

The TWA allows for natural irregularities in a worker’s day. As the worker moves throughout a facility and engages in different activities, their exposure levels will rise and fall. Sometimes their exposure will even briefly exceed the legal PEL. OSHA sets a number for that, as well, or the “acceptable maximum peak above the acceptable ceiling concentration for an 8-hr shift.” OSHA lists a concentration and a maximum duration for this figure. But the key number to focus on is the averaged PEL. Averaging the worker’s exposure over time creates a more accurate measurement.

Source: definition of TWA in federal code is here:
Source: OSHA’s annotated Z-2 table:

How do I get my air quality tested?

Air quality audits are best conducted by licensed, third party professionals. These are usually industrial hygienists who understand manufacturing processes, regulations, data collection, health effects, and other relevant criteria.

Air quality audits are comprehensive and scientific. Most likely, the auditor will set up monitors throughout your facility to measure the contaminants. These sensors will be a few feet off the ground—around the height of the breathing zone and spread in a pattern that collects representative samples of air from throughout the facility. Monitors might also be attached to select workers in order to measure their exposures. These monitors will be attached to their uniforms, not far from their head to collect air near the breathing zone.

After collecting samples and data for a certain amount of time, the auditor will take them away for processing. Samples will be tested to determine what substances were in the air. Auditors will crunch the numbers and prepare a full report on your air quality.

Having a professionally conducted air quality audit by an independent source is valuable for a lot of reasons:

  • First, it can let you know if your facility is safe for workers.
  • Second, if your air quality is lacking in one area or another, the audit can help you develop a strategy for improving it. For example, air quality that is only slightly out of regulatory compliance demands a much different solution than air that is radically out of compliance.
  • Third, if your air quality is great, it’s nice having that documented. It gives you something to brag about to new recruits. It is also nice to have in case of legal issues, if any should ever arise.
  • Fourth, if your air quality is adequate but not great, it lets everyone know that the issue should be on their radar.

Taking steps to improve your air quality isn’t just great for employees’ health and productivity, it also helps prepare you for any regulatory changes that might occur. It’s always better to make investments when you want them, rather than being told by others that you need to make them.

How can engineering processes be changed to meet air quality regulations?

One of the first steps in improving your air quality should be to look at changing your engineering processes. This is the “low-hanging fruit” that might save you a lot of trouble and expense. For example, it’s possible that cleaning a surface that gets welded or changing your weld wire might significantly reduce your weld fumes, avoiding the need for major ventilation equipment.

There are, in fact, several ways to improve your air quality before you resort to filtration and other such solutions. OSHA has collected some of these methods in their “Hierarchy of Controls,” an easy-to-use guide to adjusting your processes in ways that could solve your air quality problems.

  • The first couple options in OSHA’s list are to remove the hazard or substitute something safer for it. Perhaps the process that produces the contaminant could be replaced with a less toxic process. New materials and processes are changing manufacturing every day, so new options might be on the table. An air quality expert could help you identify these opportunities.
  • The next option is to change your engineering controls to cut or remove a threat to air quality. This includes the aforementioned adjustments in weld wire or shielding gasses, changes that can significantly reduce weld fumes or their toxicity. Changing from stick welding to MIG welding can also produce similar reductions. Isolating the process from workers is another solution. Robotic welding cells, for example, are a major step in protecting workers from direct contact with fumes. This method is also sometimes called “Prevention Through Design” (PtD). Why solve a problem when you can avoid it?
  • Another option is to cut fumes through new housekeeping controls. For example, cleaning the residue on parts that are to be welded can significantly cut weld fumes. These solutions, and many others, are listed in OSHA’s Hierarchy of Controls.

OSHA’s Hierarchy of Controls:
Prevention Through Design:

Which is better for meeting air quality regulations: source capture or ambient capture?

The question of source v. ambient capture primarily comes down to the nature of your air quality problems—namely, in the volume of fumes and the nature of the particulates. High-volume operations that produce a lot of dust or fumes are best served with a source capture solution. Failing to do so risks letting too many particulates drift around your facility, causing harm to workers and risking regulatory compliance. Equipment such as fume arms and backdraft tables are able to pull contaminants away workers as soon as they are produced. Robotic welding cells—one of the highest-volume fume producers—can be enclosed with a hood, allowing you to weld all day without filling your facility with fumes.

Contaminated air that contains a high quantity of toxic substances requires a more intensive air quality solution than more benign contaminants. For example, air that contains hexavalent chromium is much more dangerous than air that carries wood dust. The former air quality challenge calls for an intensive solution, such as source capture. You don’t want those toxic substances drifting through a facility waiting to be exhausted or to pass through an ambient capture system. While they drift, they could affect workers spread across a facility; and even a small level of exposure to these substances can cause harm.

Another factor affecting a decision regarding source or ambient capture is the layout of your facility. Overhead cranes or restricted floor space can limit your options. Sometimes an ambient capture system is the only option available. In situations like these, such a system could be paired with personal protective equipment.

Ambient capture solutions are great for facilities with operations spread across a wide area and with lower volumes of contaminants. These systems circulate the air throughout an entire facility and ensure that contaminants don’t linger and threaten workers. Applications that deal with less toxic substances are good candidates for ambient capture, as well, like the aforementioned wood dust. In these cases, an ambient capture system would both protect workers and guard against facility-wide dangers such as dust explosions.

Often, a hybrid system is worth considering. For example, in a facility where large pieces are being welded, a powerful source capture system—such as an enclosure and fume hood—might not be an option. In this situation, a fume extraction gun would be a good option for collecting most weld fumes at the source. A secondary ambient capture system would help ensure that nothing is missed. Today’s strict air quality standards demand this attention to detail.

Why can’t I just exhaust my dirty air to the outside?

The primary risk to exhausting contaminated air to the outside—besides possibly adversely affecting the community—is breaking air quality regulations of the Environmental Protection Agency (EPA). These regulations apply to the environment, rather than to workplace air, which OSHA regulates. If too many contaminants are put into the air in too short a time, your company might have a compliance problem.

Another problem with exhausting dirty air is that it often encounters a lot of workers and equipment on its way out the building. If the air is carrying toxic substances, those workers will be exposed, risking their health and OSHA compliance. Dirty surfaces can cause slip hazards, unsightliness, and malfunction problems with equipment.

A less critical but still common problem with exhausting dirty air is the prevalence of dirty roofs where exhaust vents are located. Besides being unsightly, this creates an extra housekeeping burden.

How are OSHA and ACGIH different?

In short, OSHA is a federal agency that regulates workplace safety, while the ACGIH is a scientific organization that studies occupational and environmental health issues. While the two are very different in structure and mandate, they have a relationship that is relevant for manufacturers.

OSHA, or the Occupational Safety and Health Administration, was signed into law by President Richard Nixon in 1970. The agency began work in 1971 with the mission to “assure safe and healthful working conditions for working men and women by setting and enforcing standards and by providing training, outreach, education and assistance.” Over the years, OSHA has added regulations to the legal code, most of which are contained in Standard 29 CFR Part 1910 Subpart Z. Many of these regulations set limits for worker exposure to various substances. These limits are often expressed as “permissible exposure limits,” or PEL’s. Workplaces must comply with these regulations or risk citations and fines.

OSHA oversees roughly seven million workplaces. The agency is organized under the Department of Labor and has ten regional offices, as well as area offices in most states. You can find OSHA’s frequently asked questions here.

The American Conference of Governmental Industrial Hygienists, or ACGIH, is a nonprofit organization established in 1938. Their motto is “Defining the Science of Occupational and Environmental Health.” Made up of a core of industrial hygiene workers, they collect and share information to support this goal. The organization also publishes the well-known reference work TLVs and BEIs. This annual guide for “evaluation and control of workplace exposures to chemical substances and physical agents” contains TLVs® (Threshold Limit Values, or exposure guidelines for over 700 chemical substances) and BEIs® (Biological Exposure Indices, or limits on over 80 more substances).

A TLV does not have any regulatory power in the workplace, but the number is still significant. It serves an advisory role to OSHA and to manufacturers who care about workplace safety. The ACGIH’s recommendations reflect the field’s latest research and expert analysis, so OSHA looks to it to inform its regulations. For example, if the ACGIH chooses to lower its limit for a particular substance, it is likely that OSHA will at least consider the issue. OSHA is under many conflicting pressures, so it is not an agency that acts quickly, but ACGIH recommendations are an influence on the agency. Some manufacturers who want to stay ahead of regulations and protect their workers according to the latest science follow ACGIH’s recommendations for exposure limits.

How are OSHA regulations different from EPA ones?

While the Occupational Safety and Health Administration (OSHA) regulates workplace safety, the Environmental Protection Agency (EPA) sets rules to limit environmental pollution. A manufacturer that produces contaminated air in any serious volume should be aware of both sets of regulations.

OSHA’s regulations for air quality often come in the form of permissible exposure limits (PEL’s) for workers. These standards limit how much of a certain substance a worker can be exposed to over a typical shift. If exposure exceeds that limit, an employer can be cited and possibly fined. OSHA maintains ten regional field offices, as well as area offices in most states, to inspect facilities, help employers meet the regulations and enforce the rules in case of noncompliance.

The EPA’s regulations are different—most of the relevant standards for manufacturers are based on the Clean Air Act. These regulations limit how much of a particular substance a company can release into the environment. Their concern is the health effects of these substances on the surrounding community. The EPA maintains a list of air emissions sources:

  • Nitrogen Dioxide (NO2)
  • Ozone (O3)
  • Sulfur Dioxide (SO2)
  • Particulate Matter (PM)
  • Carbon Monoxide (CO)
  • Lead (Pb)

Some of these limits affect typical manufacturers. If a facility is producing contaminated air—say, through a large welding operation—and exhausting all of it to the outside, the company may be breaking EPA regulations. Failure to comply could lead to citations and penalties.

How often do OSHA regulations change?

The simple answer is: often enough to cause concern. Because the process of changing the legal code is so complicated, these changes don’t come according to a regular schedule—but when they do, they can cause serious waves in the manufacturing sector.

When OSHA changes a regulation, it sets a timetable for implementation, explains how it will be enforced and so on. The agency will typically allow months—if not years—for employers to adjust to the new rule. While this may sound generous, if a change in regulation is significant enough, it will likely require quick and serious action from an employer.

A good example of such a change came in 2016 when OSHA changed its regulation of crystalline silica. The agency determined that the existing permissible exposure limit (PEL) for the substance was not adequately protecting workers and cut the limit in half. Manufacturers are still scrambling to adapt to the change.

How has the standard for silica dust changed?

In 2016, the Occupational Safety and Health Administration (OSHA) changed the air quality regulation for crystalline silica. Scientific evidence had accumulated that said the substance was more dangerous than previously thought. In particular, exposure to crystalline silica dust was associated with cases of lung cancer.

OSHA reduced the permissible exposure limit (PEL) to crystalline silica by half. The limit is now 50 micrograms of the substance per cubic meter of air, averaged over an eight-hour day. The agency is applying this standard to all workplaces, including construction and maritime operations. The change will affect around 676,000 workplaces and roughly 2.3 million workers.

OSHA says that engineering controls must be used to reduce exposures. These include practices such as wetting down work operations or enclosing dust-producing applications. Respirators are only allowed after these practices have been attempted to control exposures.

The change in regulation also calls for medical surveillance of workers exposed to the substance. This is meant to identify health problems before they become critical and to determine if an employee has a condition which makes them especially sensitive to the substance.

For a full list of requirements associated with this rule change, visit the OSHA site for this regulation.