FREQUENTLY ASKED QUESTIONS

What is the difference between pipe cleaner, primer/cleaner and primer?

All pipe surfaces should be thoroughly cleaned with pipe cleaner. Pipe cleaner is formulated to remove surface dirt and any oils or grease that remain on the pipe from the manufacturing process or from the work environment. Primer/cleaner and primer contain more aggressive solvents and will soften the pipe surface to allow the solvent cement to penetrate more effectively. Primer is often required by plumbing codes and sometimes a purple colored primer is specified. Colorless primers, visible under UV or black lights can be used in place of purple primers as permitted in ASTM F656. (see below)

What are “UV” primers, “black light” primers and “Unpurple” primers?

These are all terms used to describe colorless primers that are visible only under UV/black lights which are used as a substitute for purple primers. These primers function identically to standard purple primers except they are colorless and invisible to the naked eye when applied. The installer/inspector may use a “black light” or “black light” flashlight to inspect for the presence of correctly applied primer as required by the plumbing codes. These “black light” flashlights are available from the primer manufacturers and are also available at a nominal cost on the web. These “Unpurple” primers offer the benefits of a colored primer with none of the aesthetic and cleanup disadvantages of purple primers.

What temperature should solvent cements be applied?

While it is recommended that the cement be applied between 40-100 degrees F, weather conditions may not make this feasible. A strong solvent welded joint can be made at temperatures below freezing, as long as the cement is fluid, cure times are extended and other handling precautions are followed. Cements are available which are designed for temperatures outside of this temperature range – consult manufacturer’s web sites for more use and proper storage information.

What is the difference between PVC, CPVC and ABS?

These are three different types of plastic pipe used in plumbing applications that are joined by solvent cementing: PVC (Polyvinyl Chloride); CPVC (Chlorinated Polyvinyl Chloride); and ABS (Acrylonitrile-Butadiene- Styrene). PVC and ABS pipe are normally used for Drain, Waste and Vent (DWV) systems, while CPVC is used for water distribution systems. PVC pipe can be used in pressure applications - such as water mains, service lines and irrigation. It is important to choose the correct solvent cement based on the type of plastic pipe being used.

What type of applicator should be used to apply the solvent cement?

Most solvent cements come with a dauber included in the can. This dauber is typically one inch in size and be used to apply cement to pipe sizes up to 2". Installer should check the dauber size as different size cans can have large and small daubers. The dauber size should be as close as possible to ½ the diameter of the pipe. (Using a dauber which is too large in size can cause the cement to puddle in the fitting causing potential solvent stress cracking.) Above 2" diameter, a brush ½ the pipe diameter can be used, rollers should be avoided for the smaller sizes (¼” thru 3”). For above 3” diameter, it is recommended that the installer consult the manufacturer’s installation guide for possible applicators and sizes.

Should a gelled or lumpy cement be used?

Do not use gelled or thickened cements on plastic pipe. The solvents in the can will evaporate if left open for extended periods of time, causing the product to thicken or gel. It is not recommended that you attempt to thin solvent cements.

What cement should be used for PVC, CPVC and ABS pipe?

It is important to carefully select the proper solvent cement for your application. PVC cements should be used for PVC pipe and fittings, CPVC cements should be used for CPVC pipe and fittings and ABS cement should be used for ABS pipe and fittings.

Should primer or primer/cleaner be allowed to dry before applying solvent cement?

Because the primers will soften the pipe surface, it is important to apply cement to the pipe and fittings while the primer is still wet for maximum bond strength.

What are Low VOC solvent cements? 

In areas of the country where population and geography combine to produce ozone and smog air quality issues, low volatile organic compound (VOC) products, like paints and adhesives, are either recommended, or required by law. These products have special formulations that have lower solvent content and/or use alternative solvents, like acetone, that are less reactive in the atmosphere. Solvent cements and primers are produced that meet the requirements in California’s South Coast Air Quality Management District (SCAQMD) and other regions which have similar VOC regulations. These products still meet required levels of performance required by standards and third party certifiers.

Can I use solvent cements in “green” and “sustainable” building systems, like LEED?

Yes. While solvent cements contain VOC’s, the total quantity used during home construction is very small compared with other products commonly used by the gallon, like paints and other adhesives. Solvent cemented plumbing systems are essentially permanent once installed and do not need repair or reapplication. LEED V 2.2 does require the use of low VOC solvent cements in Environmental Quality credit 4.1. In order to obtain the credit point, all adhesives and sealants used on the interior of the building are to meet SCAQMD rule #1168. Low-VOC solvent cements manufactured to comply with SCAQMD and are commercially available. Solvent cemented piping systems, like ABS, PVC and CPVC each find uses in sustainable piping systems such as gray water, subsurface irrigation, radon venting, rain water catchment, and higher efficiency hot water distribution.

What are other benefits of solvent welded systems? 

Under certain conditions, and because of their flammability, larger containers of solvent cements, cleaners and primers "offered for shipment" require special placarding of vehicles. To properly follow U.S. Department of Transportation (DOT) shipping regulations, training of employees is required.     Containers with volumes under one liter are considered ORM-D (consumer commodity) by DOT and are generally exempt.    DOT does not certify hazmat employees, or endorse any private sector training program or certification. Rather, the hazmat employer must choose what training is appropriate for its employees under the Hazardous Material Regulations, and certify that employees are appropriately trained. Training must be done initially with a new employee and at least every three years. Any employee whose work directly affects hazardous materials transportation safety is required to have this training.

Where can shippers of solvent cement products learn about placarding and other DOT transportation regulations? 

Under certain conditions, and because of their flammability, larger containers of solvent cements, cleaners and primers "offered for shipment" require special placarding of vehicles. To properly follow U.S. Department of Transportation (DOT) shipping regulations, training of employees is required.     Containers with volumes under one liter are considered ORM-D (consumer commodity) by DOT and are generally exempt.    DOT does not certify hazmat employees, or endorse any private sector training program or certification. Rather, the hazmat employer must choose what training is appropriate for its employees under the Hazardous Material Regulations, and certify that employees are appropriately trained. Training must be done initially with a new employee and at least every three years. Any employee whose work directly affects hazardous materials transportation safety is required to have this training.

The following link: http://hazmat.dot.gov/training/mods/mod.html  contains links to pre-made DOT training materials your company may find useful.