Photopolymer Frequently Asked Questions
Photopolymer FAQ - While we are known for our quality materials and fabrication equipment, you will discover our reputation for training, service and technical support surpasses every supplier. For the highest quality Technical Support available contact Nova Polymers at 1-888-484-NOVA (6682) or email us at email@example.com.
Photopolymer is a photo-sensitive synthetic compound that hardens when exposed to an ultraviolet light source. Photopolymer is available in both liquid and sheet form. It has a number of applications that span a multitude of industries ? ranging from flexographic printing to rubber stamps to signage.
It wasn?t until the passing of the Americans with Disabilities Act in 1992 that photopolymer rose to prominence in the sign industry. The new ADA regulations had a major impact on tactile signage, requiring all public facilities to meet specific codes and regulations. These changes were implemented for the visually impaired and affected issues such as contrast characters, sign placement, character spacing and required the placement of Braille raised to 1/32? off the base material.
At Nova Polymers, we bond a 1/32? clear, high resolution photopolymer sheet to a variety of base substrates. Instead of the tedious routing and engraving methods, photopolymer signs are easily produced and cost-efficient. Computer generated artwork is output to a film negative which is placed on the surface of the photopolymer sheet in the processing unit then exposed to ultraviolet light ? hardening the raised area. After exposure, the material is placed in the washout tank where the unexposed photopolymer is washed away, leaving the raised area. With our unique photopolymer, washout takes place in plain tap water and its effluent is 100% biodegradable which can be disposed of in any public waste disposal system. Once the photopolymer is processed, many finishing options are available.
For tactile signage, the unique imaging characteristics of photopolymer make it the choice of fabricators as well as designers. Our specialized product line allows designers unlimited flexibility and provides fabricators with the raw material needed to meet all ADA regulations.
Clearly, photopolymer is the material of choice for all your environmental graphic design needs!
Q. Do all Photopolymer signs require a top coat?
A. Yes, regardless of material selection or if the sign is sub-surfaced painted, the photopolymer layer must be protected from UV rays with a top coat (painted color or clear coat)
Q. What type of paint can I use?
A. Nova recommends using an automotive grade acrylic polyurethane, ie. Matthews acrylic polyurethane or equivalent.
Q. How thick do I apply the paint or clear coat layer?
A. According to Matthews Paint Company, it is specified that clear coats and/or paints should have the same amount of coating (4 mil wet/2mil dry).
Q. What is a Wet Film Gauge?
A. A Wet Film Gauge is the most accurate way to measure the thickness of the paint coating when it is first applied to a surface or substrate.
Q. I am using a photopolymer sheet as a lens in a curved sign with a digital print. Do I need to apply a clear coat even though it is an interior application?
A. Yes. Regardless of the application (Interior/Exterior) a top coat must always be applied over the photopolymer. This is true for all sub surfaced painted signs, signs with sub-surface digital graphics and materials that incorporate color or patterns in the base substrate.
The 5 Step Process for Making Photopolymer Signage
For more information see the NovAcryl Processing Guidelines
Q: Isn’t the government constantly changing the ADA rules?
A: ADA sign guidelines have not changed once since 1991 when they were first written. However, various states may have published their state building codes in the meantime, and there might be some more stringent rules in your specific state. Also, ANSI (American National Standards Institute) did come out with new standards, including a completely rewritten sign section in 1998. The federal government, which is in charge of the ADA, has no control over this activity. The Federal Government is in the process of revising the ADA Guidelines.
Q: What is the new 2010 ADA Standard?
A: The Department of Justice (DOJ) amended the American with Disabilities Act on September 15, 2010. The revisions clarify and refine issues that have arisen since its implementation over twenty years ago. These changes are referred to as the "2010 Standards". On March 15, 2012, the 2010 Standard for Accessible Design or simply SAD was enforced for new construction and alterations. Please note, formal compliance is administered at the state and local levels, therefore, revisions may have already been adopted. Some states and municipalities are permitted to adopt accessibility codes even more stringent than the 2010 Standards with the approval of the U.S. Department of Justice.
Q: Will photopolymer signs still be compliant after the new ADA rules are passed?
A: The new 2010 Standards for Accessible Design do not rule out any fabrication methods. The codes only indicate that Braille dots be rounded or domed, therefore Photopolymer continues to meet all compliance guidelines.
Q: ADA signs are supposed to be "non-glare." Can we use metals for ADA signs?
A: When a substrate is use that has a shiny finish such as aluminum, a non-glare satin clear coat can be applied to the surface of the material.
Q: How do we determine contrast on signs? What colors work best?
A: Contrast is between light and dark, not between colors. For instance, a very pale grey (almost white) would be fine with a charcoal background. Brown and green or red and black do not contrast for people with defective color vision. Although contrast is not defined in the guidelines with a specific number, the minimum 70% rule is good to follow.
Q: Current ADA guidelines call for "simple" serifs. What is a simple serif?
A: There is no such term. The original writers of the ADA guidelines incorrectly used this definition of typeface. The new Rules eliminate this confusing term. Serifs on tactile characters make them more difficult to read by touch.
Q: What sign types need to follow ADA guidelines?
A: All permanent rooms and spaces are required to have an ADA compliant sign providing identification. Life safety signs identifying doors at exit passage ways, discharge, and stairwells are required to be ADA compliant and include raised characters and Braille copy. Overhead, flag-mounted, and wall-mounted signs that direct or identify need to follow ADA guidelines but do not require tactile copy.
Q: Do temporary signs need to be ADA compliant?
A: No. The new ADA defines permanent signage as an identification sign representing destinations for more than seven days. Temporary signs (signs used less than seven days) do not need to be ADA compliant.
Q: What type of Braille is used for ADA compliant signage?
A: There are two types of Braille. Grade 1 Braille is full spelling. Grade 2 Braille consists of Grade 1 Braille and 189 contractions. Grade 2 Braille is ADA compliant. 2/90 uses the new standard when creating Braille. New guidelines require Braille dots to be rounded or domed. Braille dots needs to be positioned 3/8 of an inch directly below the corresponding text and be the same color as the background.
Q: What are the guidelines for Visual Characters?
A: When raised characters and Braille copy are not mandated but signs provide direction or life safety, guidelines for Visual Characters are required. Visual characters and their background need to follow these guidelines: non-glare finish, contrast with their background, uppercase or lowercase or a combination of both, copy style to be conventional in form, and characters cannot be expanded, extended, italic, oblique, script, highly decorative, or of other unusual forms.
Q: What size does my copy need to be for ADA compliance?
A: The new codes allow for letter heights to better fit their environment. Minimum character height is 5/8 inch and 2 inches maximum for raised characters. For visual characters, a range of 5/8 inch to 2 inches is used for wall-mounted signs. Overhead signage has a 2 inch minimum character height along with height requirements above 3 inches for longer distances.
Q: Are there any ADA changes for symbol signage?
A: Yes. Pictograms need a vertical field of 6 inches. Raised characters and Braille cannot be located in this field. The equivalent verbal description needs to be placed directly below the pictogram field.
Q: At what height do ADA signs need to be installed?
A: Previously, ADA signs were mounted at 60 inches to the center of the sign. 2010 Standards provide for a range of 48 to 60 inches from the bottom to the top of sign text. This change provides for visual consistency of sign heights.
Q: What are minimum height clearances for ADA signage?
A: The bottom of overhead signage must clear 80 inches minimum above the finished floor (AFF). Wall-mounted signs must be mounted a minimum of 27 inches AFF and a maximum height of 80 inches, with a maximum protrusion into the pathway of 4 inches.
Q: Where do ADA signs need to be installed in relationship to a door?
A: When mounting ADA-compliant signage, sign location is relative to door type and swing path. The new ADA provides greater guidance for the placement of signs, allowing tactile signs to be placed on the push side of doors with a closing mechanism. This change clarifies the issue of signs on restroom doors.
- Single Door: Sign shall be next to door on latch side.
- Double Doors (one active leaf): Sign shall be located on inactive leaf.
- Double Doors (two active leaves): Sign shall be to the right of right-handed door.
- Push Doors: Sign shall be on the push side of doors with closers and without hold-open devices.
- Signs for doors without wall space (on latch side of single door or at the right side of double doors) shall be mounted on nearest adjacent wall.
- Mounting location for such signage shall be so that a person may approach within 3 inches of signage without encountering protruding objects or standing within the swing of a door.
Q: Is ADA stairwell signage necessary?
A: Yes. A tactile sign is required next to each door inside a stairwell identifying floor level and stair well. Many local fire codes require a visual-compliant minimum sign size of 18 inches high by 12 inches wide for each floor in all stairwells identifying floor level, stair level, roof access, and level of exit. These signs can be separate but 2/90 recommends tactile copy on the visual compliant sign for cost and maintenance savings. Depending on building type and state code, these signs may be required to be photoluminescent. Since local ordinances override federal, please verify with your municipality.
Q: Where can I find more factual information about the ADA and regulations?
A: More information can be found at the U.S. Department of Justice Americans with Disabilities Act ADA Home Page
The Process: How Compliant Photopolymer is Achieved
There are four main steps in creating a photopolymer sign - artwork design, film generation, photopolymer processing and finishing.
- We start by reducing the actual size of the Braille diameter in our Workflow Manager (WM) software. WM is designed to follow all the current ADA guidelines which include kerning, character size, Braille placement, fonts and more. The dot size is reduced to .044" so that we can build a shoulder during the exposure process.
- Once the files are created a film negative needs to be generated with high enough density that allows for the proper exposure. Our InkStar Film Solution creates film with the proper density.
- The exposure of the photopolymer is measured using a 21 Step Stouffer Scale. This scale measures UV output which takes into account the wear on the bulbs ensuring proper exposure throughout the bulbs lifecycle. By using the scale we can accurately measure the exact size of the Braille.
- Once you have the proper dot size in the artwork and adequate exposure you will need to apply a top coat. This means a coating of paint for surface decorated signs or a clear coat for signs that are decorated sub-surface. We work very closely with Matthews Paint and per their specification you will need to apply a 4mil wet /2mil dry top coat on all photopolymer signs. This coating is the final step in creating complaint photopolymer Braille dots that "have a domed or rounded shape."