Nobody knows better than Techspray the challenges of cleaning trains, signal devices, control panels and anything else that gets covered with grease and dirt. Our contact cleaners are widely used in some of the largest subway systems in the US to help keep the trains running on time.
Techspray offers a variety of solvents, industrial degreasers, and water-based cleaner that allows you to match the right products for your cleaning needs. Maintenance cleaners clean oil and contaminants off of metal parts, printed circuit boards, barcode instruments, switch boxes, gear boxes, and engines.
Our contact cleaners remove oxidation, oil, and other contaminants from contacts, metal switches, motors, relays, generators, edge connectors, buss bars, circuit breakers, scales, and sensors.
Techspray's PWR4 Transit Equipment Degreaser is a single purpose transit degreaser, with strong removal ability of an oxidized hydraulic fluid, carbonized oils and fuels, lubricating oils and greases, and other organic residues. It is fast evaporating, quick penetrating, and ideal for cleaning heavily soiled parts.
Every organization using hazardous chemicals within their facility has the responsibility to equip their facility and personnel to maintain exposure levels below the TLV. Personal monitoring badges can be used to measure exposure of a specific material. Then, depending on the threshold limit and the application, exposure can be controlled with PPE like masks, face shields, respirators, and even coveralls. If they don’t reduce exposure below the recommended limit, you will need to consider a special ventilation hood or even containment booth. As you can see, as the exposure limit gets down to a certain level, the equipment required to safely use the solvent can get impractical. At that point, your best option is to consider a safer alternative.
The personal hazard associated with a solvent is often defined using Threshold Limit Value (TLV), which is the recommended average exposure in an 8-hour day, 40 hour work week. The lower the TLV of a particular substance, the less a worker can be exposed to without harmful effects. TLV is stated on the SDS of chemical products, in additional to recommended personal protection equipment (or PPE). The threshold limit value of a solvent is generally set by the American Conference of Governmental Industrial Hygienists (ACGIH). The unit of measure is Parts Per Million (PPM).
A degreaser is intended to clean a surface, so remove contamination. A degreaser is designed specifically to remove oils, greases, and lubricants. Sanitizers are intended to kill various pathogenic agents, like bacteria and viruses. There are materials that can do both, like 70% isopropyl alcohol (per CDC guidelines for hard surface disinfecting), but don’t assume all degreasers will kill pathogens.
The ingredients of a degreaser can vary wildly depending on the product. Generally speaking, they fall into 2 camps: 1) solvent cleaners – this includes alcohols (like isopropyl alcohol, or ethyl alcohol), hydrocarbons (like heptane and mineral spirits), ketones (like acetone and xylene), and more exotic compounds and blends. 2) water-based cleaners – these include ingredients dissolved or blended with water. Which is best for your application depends on the type of soil and various requirements like performance, evaporation rate, toxicity limits, and environmental regulations.
Windex (or other similar glass cleaners) could be considered a very light-duty degreaser. Glass cleaners can remove very light oils, like fingerprints, but will fall very short with heavier oils, greases and lubricants. Techspray offers a foaming glass cleaner (part #1625-18S) and water-based Eco-Shine (1505-QT) for light cleaning, and products like G3 Maintenance Cleaner (1630-16S), PWR-4 Maintenance Cleaner (3400-20S), and E-LINE Maintenance Cleaner (1620-10S) for more heavy-duty oils, greases and lubricants.
N-Propyl Bromide (nPB), Trichloroethylene (TCE) and Perchloroethylene (Perc) are highly toxic chemicals commonly used in degreasers to provide cleaning performance in a nonflammable formula. There are documented court cases where workers suffered major health effects when exposed to high levels of these chemicals. Workers reported headaches, dizziness, and even loss of full body control. There are also possible links to reproductive problems and cancer. All of this has caused maintenance facilities to reconsider their solvent choices, especially with manual cleaning when exposure tends to be higher.
Rigid plastics like ABS, polycarbonate (trade name Lexan), and acrylic materials like Plexiglass can be very sensitive to harsh solvents like toluene, xylene, and acetone. Alcohol and hydrocarbon based solvents tend to be better on sensitive plastics. Rubber, silicone or other seals or gaskets made of elastomeric (soft) materials can have a tendency to swell or shrink with exposure to harsh solvents. After the solvent flashes off, they may spring back to their original dimensions, or be permanently changed, impacting the effectiveness of the seal. Polyester or Teflon based gasketing materials are less prone to this type of damage from harsh solvents.
A degreaser is a cleaner designed to remove grease, oils, cutting fluids, corrosion inhibitors, handling soils, finger prints, and other contamination common in assembly, stamping, other types of metal fabrication, refineries, motor repair, airplane hangars, and many other applications. Degreasers go by a number of different names, including precision cleaner, maintenance cleaner, and specific for automotive repair, carb cleaner, brake cleaner. The objective for a degreaser is to remove the offending soil quickly, avoiding as much wiping and scrubbing as possible. Degreasing solvents are commonly packaged as an aerosol for convenience. Aerosols have the added advantage of providing a forceful spray that creates agitation and to penetrate all the crevices of the part.
While the contact surfaces of connectors are metal, they are often housed in plastic, and rubber gaskets to seal everything from the outside environment. If the solvent used in a contact cleaner is incompatible with the plastic, it can craze (create small cracks), embrittle, or soften the material. Rubber seals may swell, shrink or even dissolve if exposed to a harsh solvent. Rigid plastics like ABS, polycarbonate (trade name Lexan), and acrylic materials like Plexiglass can be very sensitive to harsh solvents like toluene, xylene, and acetone. Alcohol and hydrocarbon based solvents tend to be better on sensitive plastics. Rubber, silicone or other seals or gaskets made of elastomeric (soft) materials can have a tendency to swell or shrink with exposure to harsh solvents. After the solvent flashes off, they may spring back to their original dimensions, or be permanently changed, impacting the effectiveness of the seal. Polyester or Teflon based gasketing materials are less prone to this type of damage from harsh solvents. A new contact cleaner should always be tested before use on any questionable applications, using any live (and expensive) equipment.
Dielectric strength is defined as the maximum electric field that the material can withstand under ideal conditions without breaking down. Breaking down in this sense is described as a failure of insulating properties, where the electricity breaks free of the conductors and burns a path through the weakest area of the insulating materials. And, it’s not a breakdown over time. As soon as there is enough free electricity it will immediately or, in a nanosecond, discharge through the insulating material. If it doesn’t discharge through, it’s going to severely degrade it to the point it is of no insulating use. So you want a cleaner with high dielectric strength because you want it to clean without conducting. Remember, certain soils such as carbon are effective conductors of electricity, and both the combination of the conductivity of the soil and cleaning solution need to be taken into consideration. You want the cleaner to act as an insulator to protect you while you are using it. It seems basic, but it should clean an energized surface, not conduct electricity back to you or to your insulating material and it should not corrupt or attack the circuit you are cleaning. When selecting a contact cleaner, look for dielectric strength in the product specifications. The higher the number the better, and you want to avoid spraying energized contacts with anything below 30 kV (30,000 volts).
There is no way to give a definite answer for all circumstances, because safety is highly dependent on the amount voltage and amperage as well as environmental factors such as the equipment, working environment, etc. On the other hand, choosing a contact cleaner with high dielectric strength or breakdown (also called withstand) voltage increases safety when you do have to clean energized equipment. BEFORE you start spraying, we strongly recommend you shut down power to avoid the potential of sparks, electrical shorts or discharges, and other safety hazards. If, for whatever reason, you don’t have the option of disconnecting the power, look for electrical contact cleaners with a dielectric strength above 30 kV (30,000 volts). Choosing a nonflammable cleaner would also add a layer of safety in case there is a spark.
While it isn’t always necessary, a nonflammable contact cleaner would be the safest option if the vapors or liquid could be exposed to sparks, open flames, or hot surfaces. Of course, when the electrical device is powered, there is a much great potential for sparks. Many commercially available contact cleaners contain alcohols and hydrocarbon solvents, which are very flammable. They are economical and effective cleaners, but can pose a safety hazard without proper ventilation, and if there are open flames, sparks (e.g. welding process), or hot surfaces nearby. Nonflammable contact cleaners are available to avoid these safety issues.