Environmental Safety Solutions LLC is a manufacturer of Dust Suppression Accessories for the construction trades.  We at ESS  feel an obligation to the American construction worker to provide safety in the workplace. In that regard we submit this information and suggestions to Cal/OSHA in reference to Dust Suppression. ESS is not the only manufacturer of Dust Suppression accessories for the construction trades.   Dependant upon the tool ie: demolition hammers, grinders ,floor scrapers, etc., there are many products available.  Most of these products use similar designs and technology.  To name a few, Dustcontrol Inc, Dustless Technologies, and many more. We feel we are leading the way in dust suppression technology.. 

Both tool manufacturers and vacuum manufacturers have been working with ESS to develop better and more efficient products to meet our goal of creating a safer work environment.   Some of the tool manufacturers you might recognize such as Robert Bosch Tools, Hitachi tools, just to name a few.  On the vacuum side, both Nilfisk and Ruwac vacuums have engaged in joint R& D projects with ESS. 

We have had the ESS Enviroboot tested by an independent testing lab.  I am attaching some older reports for your..  The final testing in January showed the Enviroboot to be over 90 percent effective in the removal and containment of airborne particulate matter created by the hammer effect. 

Although we are specifically addressing silica dust, when using a demolition hammer many additional types of dusts and molds are dispersed into the air.  Many of the dust suppression accessories mentioned will help entrap them as well.

The use of water as a dust suppressant, is not a very good method and can lead to additional types of contamination.  Water runoff can contaminate pools, ponds and streams.  When used on interior surfaces for dust suppression, water usually evaporates leaving a film of fine dust that can be disseminated into the air by air currents or walking on the dust .  On exterior demolition jobs, wind, and cars passing by can also spread dust contamination.  A good example of when not to use water would be the demolition of a garage floor.  These floors are usually contaminated with additional auto products (ie Ethylene glycol, oil and other auto fluids).  The use of water can spread this contamination.

Vacuums come in various sizes, CFM (Cubic Feet Per Minute)  ratings and inches of water column lift.  Not all are suitable for use in dust suppression.  High water column lift and CFM are important.  For the purpose of dust suppression, these vacuums must be completely sealed with no leakage from seals and gaskets. 

Only HEPA filtered vacuums using a certified HEPA filter should be used.  These certified HEPA filters should filter down to .3 microns.  There are many configurations of filtration for these vacuums.  Pre filters should also be a requirement with disposable  bags so as to remove particulate matter safely.  When in an enclosed  environment these standards should be mandatory.  Without proper filtration, cross contamination has and will become an ongoing issue.

Environmental Safety Solutions LLC is presently involved in R&D on the following and will soon have products for all mentioned.

1 -- Larger electric, pneumatic and hydraulic breaker hammers (70 lbs and above)

2 – Smaller demolition hammers   (50 to 60 lbs)

2 – Various size chipping hammers

3 – Various size hammer drills

4 – Needle and scaling hammers

5 --Both small and large grinders.

Above will be adapted for electric hydraulic and pneumatic tools. 

The documents listed below or excerpts have been copied from various web sites such as OSHA, NIOSH/CDC. There are many references made to dust control.  Unfortunately to the average layman, these are difficult to comprehend.  If new legislation and codes are to be written, they should be written in a language that the average person can comprehend.  OSHA has many references to this subject scattered throughout their website, but not consolidated in one area.  Their limits on allowable breathable dust is calculated from a formula.  This formula is referenced in several documents and it is difficult to find all the variables.   

I have also highlighted several areas that are pertinent to this legislation.

For further information please see the references at the end of this document.

  From NIOSH

http://www.cdc.gov/niosh/92-102.html

CURRENT EXPOSURE LIMITS

The current OSHA permissible exposure limit (PEL) for respirable crystalline silica (quartz) is 100 µg/m³ as an 8-hour time-weighted average (TWA) [29 CFR** 1910.1000]. The NIOSH recommended exposure limit (REL) for respirable crystalline silica is 50 µg/m³ as a TWA for up to 10 hours/day during a 40-hour workweek [NIOSH 1974b]. This REL is intended to prevent silicosis. However, evidence indicates that crystalline silica is a potential occupational carcinogen [NIOSH 1988a; IARC 1987; DHHS 1991], and NIOSH is reviewing the data on carcinogenicity.

HEALTH EFFECTS OF CRYSTALLINE SILICA EXPOSURE

A worker may develop any of three types of silicosis, depending on the airborne concentration of crystalline silica:

• Chronic silicosis, which usually occurs after 10 or more years of exposure to crystalline silica at relatively low concentrations
• Accelerated silicosis, which results from exposure to high concentrations of crystalline silica and develops 5 to 10 years after the initial exposure
• Acute silicosis, which occurs where exposure concentrations are the highest and can cause symptoms to develop within a few weeks to 4 or 5 years after the initial exposure [Peters 1986; Ziskind et al. 1976].

Silicosis (especially the acute form) is characterized by shortness of breath, fever, and cyanosis (bluish skin); it may often be misdiagnosed as pulmonary edema (fluid in the lungs), pneumonia, or tuberculosis. Severe mycobacterial or fungal infections often complicate silicosis and may be fatal in many cases [Ziskind et al. 1976; Owens et al. 1988; Bailey et al. 1974]. Fungal or mycobacterial infections are believed to result when the lung scavenger cells (macrophages) that fight these diseases are overwhelmed with silica dust and are unable to kill mycobacteria and other organisms [Allison and Hart 1968; Ng and Chan 1991]. About half of the mycobacterial infections are caused by Mycobacterium tuberculosis, with the other half caused by M. kansasii and M. avium-intracellular [Owens et al. 1988]. Nocardia and Cryptococcus may also cause lung infections in silicosis victims [Ziskind et al. 1976]. Investigations usually show the lungs to be filled with silica crystals and a protein material [Owens et al. 1988; Buechner and Ansari 1969].

Description of Silicosis

Silicosis is a disabling and often fatal lung disease caused by breathing dust that has very small pieces of crystalline silica in it. Crystalline silica is found in concrete, masonry, sandstone, rock, paint, and other abrasives. The cutting, breaking, crushing, drilling, grinding, or abrasive blasting of these materials may produce fine silica dust. It can also be in soil, mortar, plaster, and shingles. The very small pieces of silica dust get in the air that you breathe and become trapped in your lungs. Even the very small pieces of dust that you cannot see will harm you. As the dust builds up in your lungs, the lungs are damaged and it becomes harder to breathe.

Silicosis: Learn the Facts!

Do you work in construction or do abrasive blasting?

If so, here are some important facts you need to know:

• Since 1968, more than 14,000 workers in the U.S. have died from a disease called silicosis.
• In the U.S. each year more than 200 workers die with this disease while hundreds more become disabled.
• Many workers with silicosis are only in their thirties; some are as young as 22 years old. Many of them are unable to take care of themselves and their families.

Types of Silicosis

There are three types of silicosis:

• Chronic silicosis: Usually occurs after 10 or more years of exposure to crystalline silica at low levels. This is the most common type of silicosis.
• Accelerated silicosis: Results from exposure to higher levels of crystalline silica and occurs 5 to 10 years after exposure.
• Acute silicosis: Can occur after only weeks or months of exposure to very high levels of crystalline silica. Death occurs within months. The lungs drown in their own fluids.

What Type of Respirator Should I Use?

Choosing the right respirator that fits you snugly is important for protecting your health. Your employer will help you choose the type of respirator you need. ALWAYS USE NIOSH-APPROVED RESPIRATORS. The type of respirator you need depends on:

• The amount of silica dust to which you are exposed, and
• The kind of work you need to do.
• If you must do abrasive blasting, use only a type CE pressure demand abrasive blasting respirator (see photo 7).

Respirators used for protection from crystalline silica should not cause undue discomfort. If you have problems with your respirators, report immediately to your supervisor.

References

*******************************************

OSHA

Regulations (Standards - 29 CFR)
Air contaminants. - 1910.1000

1910.1000(e)

To achieve compliance with paragraphs (a) through (d) of this section, administrative or engineering controls must first be determined and implemented whenever feasible. When such controls are not feasible to achieve full compliance, protective equipment or any other protective measures shall be used to keep the exposure of employees to air contaminants within the limits prescribed in this section. Any equipment and/or technical measures used for this purpose must be approved for each particular use by a competent industrial hygienist or other technically qualified person. Whenever respirators are used, their use shall comply with 1910.134.

[71 FR 16673, April 3, 2006]

NIOSH /cdc

Silica...It's Not Just Dust

Silica Dust Causes Silicosis

What ROCK DRILLERS can do to protect their lungs from silica dust

How To Protect Yourself

Maximize Dry Dust Collection

• Provide inside corner flaps for deck shrouds (skirts).
• Install an air-ring seal where the drill pipe passes through the drill deck.
• Install or upgrade dust collector fans so the collector airflow/bailing airflow ratio is greater than 3:1.
• When safe to do so, raise the level of the drill in steps as the job progresses to minimize dust leakage between the deck shrouds (skirt) and the ground.
• Enclose the area around the collector discharge with brattice cloth or a flexible hose to prevent recirculation of dust that has already been collected.
• Lower the deck shroud (skirt) after it has been lifted to shovel cuttings.
• Use proper dust control equipment.

The above document from NIOSH/CDC refers to rock drilling, the silica dust created by the hammer-drilling effect which is similar to the hammer effect of Demolition /Jack hammers, chipping hammers and smaller hammer drills.  All produce a similar type dust that when inhaled can and will cause Silicosis. 

The above document issued by OSHA is related to software developed by OSHA in regards to asbestos abatement.  This same software could be rewritten to envelope silica dust abatement.  There is not much difference between silica and asbestos when it pertains to distribution into the air we breathe. 

See: http://www.osha.gov/dts/osta/oshasoft/asbestos/asbxwin.html

        http://www.osha.gov/dts/osta/oshasoft/asbestos/index.html

Terminology:  jack hammer, demolition hammer and breaker hammer are all interchangeable names. There does not appear to be an industry standard naming convention.  These tools are used in a similar manner and have similar appearance.  All produce the same results, to break up concrete and masonry products. 

Reference material:

http://www.cdc.gov/niosh/92-102.html

http://www.cdc.gov/niosh/homepage.html

http://www.cdc.gov/niosh/consilic.html

http://www.cdc.gov/niosh/topics/silica/

http://www.osha.gov/SLTC/etools/silica/index.html

http://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=STANDARDS&p_id=10628

http://www.osha.gov/pls/oshaweb/owasrch.search_form?p_doc_type=STANDARDS&p_toc_level=0&p_keyvalue=&p_status=CURRENT

http://www.osha.gov/pls/oshaweb/owastand.display_standard_group?p_toc_level=1&p_part_number=1926

http://pathhsw5m54.ucsf.edu/case20/silicosis.html

http://www.cdc.gov/niosh/92-107.html

http://www.osha.gov/dcsp/osp/stateprogs/new_york.html

http://www.cdc.gov/niosh/docs/2004-108/default.html

http://www.osha.gov/SLTC/silicacrystalline/index.html

http://www.osha.gov/SLTC/silicacrystalline/index.html

http://www.osha.gov/SLTC/silicacrystalline/standards.html

http://www.osha.gov/dts/osta/oshasoft/asbestos/asbxwin.html

http://www.nsc.org

http://www.nsc.org/lrs/statinfo/odds.htm

micron = one millionth of a meter

Typical Specifications for Dust Suppression Accessories

Vacuum Specifications

1.   Industrial vacuum manufactured by ISO 9001 registered company.

2.   Vacuum must be minimum of 120 CFM and/or meet the requirements of the dust 

      suppression attachment as recommended by the attachment manufacturer.

3.   Vacuum must include dual stage by-pass motors for longevity.

4.   Vacuum housing must be manufactured out of a rust and dent free material, (no  

      painted steel).  Fiberglass Or plastic type material preferred.

5.   Vacuum must have a collection bag for the disposal of dust..

6.   Vacuum Filter must be 99.95% efficient @ 0.3 microns.

7.   Vacuum must have heavy duty casters (double ball bearing) .

8.   Vacuum must be completely grounded to avoid static build up.

9.   No visible dust can ever be returned from the exhaust of the vacuum.

10. Vacuum must have sound suppression and be below 80 dB. @ 3ft.

11. Vacuum must be able to handle at least 15 feet of 2" vacuum hose without any loss of  

      suction.

12. Vacuum must be able to pick up fine particles for at least 20 minutes without loss of   

      suction.

13. Vacuums HEPA filter must be individually DOP tested and approved at the CFM rating the vacuum.

14. HEPA filter must pass all standards.

EnviroBoot Specifications   (EB-1)

1. Attach to hammer with approved adaptors only.
2. Attach only to approved hammers
3. Attach two inch hose from vacuum unit. Smaller hoses are not recommended.
4. EB-1 is to be attached to recommended vacuum unit having a minimum CFM rating of 120
5. Use only approved hoses and fittings
6. Adjust height of boot so as to allow proper viewing of chisel end during normal operation

NOTE:  This spec is for the Enviroboot, but can be adapted for many other dust suppression accessories.