Typical Accessories for Ductless Fume Hoods

Once you've decided on a Ductless Fume Hood, you should consider what complementary accessories may further improve your respiratory safety engineering controls.

Here are some examples:




A Magnehelic Gage (or Filter Saturation Gage)

Magnehelic Gages (or Minihelic Gages) are used on Fume Hoods to measure filter saturation.

These compact devices are used to measure static pressure on particulate filters [i.e. pre-filters, HEPA filters, ASHRAE filters]. When the filter in your Fume Hood begins to clog, the needle on the gage drops. When it has reached a certain point, it is time to change the filter. If you do not monitor filter saturation, it can be difficult to tell when the efficiency of the filter starts to dwindle and neglect to capture hazardous particulate or dust.

If you have questions about filter saturation in your Sentry Air Systems Fume Hood, contact your Sales Rep.

Velometer

Velometers are designed to measure hood face velocities in feet per minute. This measurement is taken at the inlet (or sash) of the hood.

Several health and safety organizations recommend good practices for fume hood face velocities. Here are some examples:

OSHA (National Research Council Recommendations Concerning Chemical Hygiene In Laboratories, Section4G): "[...] airflow into and within the hood should not be excessively turbulent; hood face velocity should be adequate (typically 60-100 fpm)"

ANSI/AIHA (American National Standards Institute/American Industrial Hygiene Association, Standard Z9.5-1992, Section 5.7): "Each hood shall maintain an average face velocity of 80-120 fpm with no face velocity measurement more than plus or minus 20% of the average." (source)

S.E.F.A. (Scientific Equipment & Furniture Association, 1.2-1996, Section 5.2): "Government codes, rules, and regulations may require specific face velocities. A fume hood face velocity of 100 fpm is considered acceptable in standard practice. In certain situations face velocity of up to 125 fpm or as low as 75 fpm may be acceptable to meet require capture velocity of the fume hood." (source)

Hour Counter

Hour Counters keep track of how many hours the Ductless Fume Hood is in operation. This can give the operator a better idea of when filter changes need to take place. The hour counter can easily be reset once the filters are changed.

Spill Trays

Spill Trays are helpful when chemicals, other liquids, and powders are being utilized in your Ductless Fume Hood. They allow for easy clean-up and are available in a variety of options including fiberglass, anti-skid material, NSF-Certified, and static-dissipative material.

Disinfectant Spray & Anti-Static Wipes

CaviCide® is a non-toxic surface disinfectant that is designed to kill certain bacteria and viruses [see product website for details]. It is recommended for use on a variety of laboratory and hospital equipment and will not harm the surface of your fume hood.

Pro-Wipes®880 are polypropylene nonwoven wipes. They are recommended for use in cleanroom environments because of their very low particle and fiber generation. These multi-layer wipes are compatible with a variety of acid solvents and common cleaning and disinfecting solutions (including Cavicide®). Ideal for use in a variety of laboratory, biomedical, and pharmaceutical compounding environments.

Clean & Polish Kit

This clean and polish kit is designed for use on acrylic and polycarbonate. Other cleaning solutions have the potential to scratch or mar these materials.

Sentry Air Systems manufactures an extensive line of Ductless Fume Hoods, ranging in size from 12" Wide to 70" Wide. Custom fume hoods are also available. For more information:

• Call us at 1.800.799.4609
• Email us at sales@sentryair.com
• Fill out this form to receive more information from a Sentry Air Systems Applications Specialist.

How to File a Complaint with OSHA for Poor Indoor Air Quality at Work

Poor Indoor Air Quality Can Affect your Health and Job Performance

Poor indoor air quality can be a common problem in workplaces. Because employees spend a large portion of their day at work, the indoor environmental quality of work facilities can have a noticeable and sometimes chronic effect on employee health. Typical undesirable air quality conditions include poor ventilation, mold exposure, temperature and humidity extremes, and potential exposure to workplace chemicals. These conditions may lead to frequent headaches, lethargy, cough, and have the potential to cause more serious conditions like asthma and pneumonia. [source: http://www.osha.gov/SLTC/indoorairquality/faqs.html]

Image Source: osha.gov

The Occupational Safety & Health Administration (OSHA) provides other frequently asked questions about indoor air quality on their website.

If You Think Your Workplace Has An Air Quality Problem

If you believe that the air quality at your place of employment is negatively affecting your health, OSHA recommends first asking your employer to check the ventilation, heating and air conditioning systems to make sure there is no water damage and that these systems are performing adequately based on the building use and occupancy.

There is not a single test that can verify if the building has an indoor air quality problem. General measurements regarding temperature, humidity, and air flow should be monitored, and a general walk-through of the facility should turn up leaks, pest problems, and standing water. Additional tests, like radon and asbestos, may need to be performed based on building regulations.

If you have symptoms that you believe are related to an air quality problem, OSHA recommends discussing it with your doctor.

[source: http://www.osha.gov/SLTC/indoorairquality/faqs.html]

If these requests do not work, employees have the right to contact OSHA:

The Occupational Safety and Health Act of 1970 [OSHAct]

Under this act, employees have the right to a safe workplace. As an employee, you can file a complaint and request an OSHA inspection of your workplace if you believe there is a serious hazard or if OSHA standards are not being followed.

Options for contacting OSHA:

Online: You can find the online complaint form here: http://www.osha.gov/pls/osha7/eComplaintForm.html

Download [Fax/Mail]: You can download the OSHA complaint form [pdf] and then fax or mail it to your local OSHA Regional or Area Office (you can also request this form from one of these offices). You can find your Regional or Area office here.

Telephone: By using the office-locator tool listed above, you'll be able to access the telephone number of your Regional or Area OSHA office.

[source: http://www.osha.gov/as/opa/worker/complain.html#3]

The Whistleblower Protection Program

The OSHAct also prohibits employers from retaliating or discriminating against an employee who files a complaint or participates in additional safety and health activities [including refusing to work because of imminent danger]. There are twenty-one whistleblower protection statues.

Image Source: whistleblowers.gov

According to OSHA, some examples of retaliation and discrimination include:

• firing or laying off
• demoting
• denying overtime or promotion
• denial of benefits
• discipline
• making threats
• reducing pay or hours

[source: http://www.whistleblowers.gov/index.html]

If you believe that you have been discriminated for exercising your rights under the OSHAct, you must file your Discrimination Complaint "within 30 DAYS of the alleged discrimination" according to OSHA. They recommend contacting your local OSHA office right away to file this complaint.

For additional information on indoor air quality and filing complaints with OSHA, visit these helpful links:

"How to File a Complaint with OSHA" osha.gov
"OSHA: We Can Help"- information about the OSHAct of 1970 and Worker Rights. osha.gov
"Indoor Air Quality" osha.gov
"Indoor Air Quality: Frequently Asked Questions" osha.gov
"The WhistleBlower Protection Program" whistleblowers.gov

Video Case Study on Occupational Asthma from Welding Smoke

If you're a welder or are commonly exposed to welding fumes because of your occupation, we recommend watching this case study video produced by the national watchdog for work-related health in Great Britain.

In the video, Phil Hynes, a welder for 16 years, explains how he developed occupational asthma and the impact it had on his life. The illness forced him to quit his job. He now lives with chronic asthma that greatly affects his life with his two young daughters.

View Video Here: http://www.hse.gov.uk/lev/reallifestories.htm

Welders who perform their jobs without the assistance of local exhaust ventilation or comparable safety engineering controls should discuss the situation with their health and safety advisor, third-party industrial hygeniest, or other safety professional.

For additional information on welding fumes, visit some of our past blog entries listed below (not associated with the Health and Safety Executive of Great Britain). You can also visit The Occupational Safety & Health Administration's (OSHA) website for information on the hazards of welding.

Additional Information:

• The Hazards of Welding Smoke
• Awareness: Occupational Asthma
• New OSHA Hexavalent Chromium Requirement
• Spotlight: Portable Welding Fume Extractor
• Testimonial: Fume Extraction for Welding Stainless Steel
• Application Profile: Welding with Model 450 Portable Floor Fume Extractor
• Metal Fume Fever
• Welding, Manganese Fumes, and Related Negative Health Effects
• Portable Fume Extractor for Elevated Welding Operations

How Does a Ductless Fume Hood Work?

Ductless Fume Hoods, often referred to as "Ductless Containment Hoods", are used in a wide variety of industries including manufacturing, medical, chemical, laboratory, and pharmaceutical. These negative-pressure systems are designed to protect the operator, as opposed to positive-pressure systems (e.g. Portable Clean Room Hoods) that are designed to protect the application or product.

There a few key characteristics that distinguish Ductless Fume Hoods from Conventional Ducted Fume Hoods (that typically vent outdoors):

• A "recirculating" air pattern and no external ducting or venting.
• The use of high-quality filtration media.
• Benefits including environmentally-friendly operation, energy efficiency, cost efficiency, minimal maintenance, and mobility.

Recirculating Air Pattern & Filtration Media

The most significant difference between a Ductless Fume Hood and Conventional Ducted Fume Hood is the exhaust method. While the exhausting air on Ducted (External Venting) Hoods typically empties outdoors (with or without filtration), Ductless Fume Hoods are designed to recirculate filtered air back into the immediate environment.

Click picture to view a larger image.

The diagram above outlines the major steps:

1. Operators perform their process in the work area of the hood. The access area at the front of the hood is often referred to as the "sash ". Sentry Air's standard sash opening is 8" H. While performing in the work area, fume and particulate emissions from the application are quickly pulled into the filtration system by a powerful fan situated on top of the hood.

Click picture to view a larger image.

Click picture to view a larger image.

2. Air is processed through a pre-filter, which captures some of the particles.

3. Air is passed through the main filter and the majority of contaminants are captures. Main filter options include:

• HEPA Filter [up to 99.97% efficient on particles 0.3 microns and larger]
• ASHRAE Filter [up to 95% efficient on particles 0.5 microns and larger]
• ULPA Filter [up to 99.9995% efficient on particles 0.12 microns and larger]
• Activated Carbon Filter [efficiency rate varies with the chemical being extracted]
• Specialty-blended Filters [e.g. Acid Gas, Aldehydes, Ammonia, Mercury]

4. Once filtered, air is distributed back into the immediate environment.

Other Features/Benefits

Envrionmentally-Friendly: In many cases, ducted exhaust hoods empty extracted fume and particulate directly outdoors without sending it through a filtration system first. Ductless Fume Hoods trap hazardous particulate in filters so they can be disposed of properly.

Energy Efficiency/Cost Efficiency: Ductless Fume Hoods recirculate existing room air, while externally ducting systems remove heated, cooled, or dehumidified air outdoors, which requires that air to be replaced. This has the potential to waste energy and increase cost.

Recirculating vs. Exhausting Systems

Shown with a wall-mounted fume extractor, but the

same concept applies to Ductless Fume Hoods.

Click picture to view a larger image.

Minimal Maintenance & Installation Requirements/Easy Mobility: While externally ducting exhaust hoods require complicated installation because of ducting construction, Ductless Fume Hoods can be up and running with minimal installation. They are essentially "plug and play" solutions. Ductless Containment Hoods do not require any ducting or external venting and can be moved from location to location with relative ease. The only maintenance requirements are replacing saturated filters and wiping the hood down with appropriate cleaning supplies from time to time.

Sentry Air Systems offers an extensive line of standard and custom Ductless Fume Hoods. Standard sizes include 12", 18", 24", 30", 40", 50", 60", 70" widths, and custom modifications include, but are not limited to, size, material, cutouts, air volume, and multiple points of entry.

Take a look at some custom examples below:

Custom Fume Hoods by Sentry Air Systems

View more presentations from Sentry Air Systems, Inc.

For more information:  visit our website, call us at 1.800.799.4609, email us at sales@sentryair.com, or fill out this form to receive more information from a Sentry Air Systems Applications Specialist.