Using Foam(ed) Plastics
Occasionally, CalArts students use foam(ed) plastics to fabricate characters, sets, and props for their productions, especially when working with stop-motion animation. The following are guidelines for using these materials safely.
Foam(ed) plastics are products made of petroleum distillates which can ignite when used in connection with heat from a hot wire or welding / cutting operation (hot work), or when used in close proximity to a fire effect or special effect / pyrotechnic device. Accordingly, it is recommended that only approved fire resistant foam(ed) plastics be used.
The following types of foam are most commonly used in set and prop construction:
- Sprayable polyurethane foam
- HSF 110 Pour Foam, Class 1
- Two-part rigid foam (AB foam)
- Expanded Polystyrene (EPS) or polyurethane or polystyrene foam blocks
Potential Health Hazard From Foam(ed) Plastics
The primary hazards in working with or around foam(ed) plastics are adverse health effects from direct exposure to foam(ed) plastics, and injuries caused from ignition of foam(ed) plastics. Although foam(ed) plastics can be used safely, they must be handled in accordance with the procedures designed to minimize exposure and ignition. When foam products burn they will generate dense clouds of black smoke and a variety of toxic gases, including carbon dioxide, carbon monoxide, oxides of nitrogen, and traces of hydrogen cyanide. All precautions must be taken to avoid ignition of foam(ed) plastics to prevent inhalation of potentially hazardous smoke and other injuries, such as burns. If inhalation of potentially hazardous smoke occurs, immediately seek medical attention.
Exposure to Foam(ed) Plastics
Typically, there are three primary routes of possible exposure to foam(ed) plastics and the vapors released from such products: inhalation, skin contact, and eye contact.
- Airborne vapors, aerosol mists, and particulates are irritating to the respiratory tract.
- Symptoms of overexposure may include tightness of the chest, difficult or labored breathing, headache, nausea, or vomiting. Exposure to higher concentrations may result in chemical bronchitis, pneumonitis, and pulmonary edema.
- Some people may become sensitized and experience severe asthma-like attacks whenever they are subsequently exposed to even minute amounts of vapor. Once sensitized, these people must avoid any further exposure.
- Skin Contact
- Although a single prolonged exposure is not likely to result in the foam material being absorbed through the skin in acutely toxic amounts, skin contact may discolor the skin and cause irritation. Skin contact may produce contact dermatitis and skin sensitization. Therefore, avoid contact with the skin.
- Eye Contact
- Direct or indirect contact with foam material may cause eye irritation, temporary blurred vision or corneal damage. Be aware that ordinary safety goggles or face masks will not prevent eye irritation from high concentrations of vapor.
General Precautions While Cutting, Craving, Sculpting, Bluing, and/or Spraying
- Skin and eye protection should be used during all normal working operations. Personal protective equipment (PPE) includes, but is not limited to, safety glasses, chemical worker’s goggles, chemical gloves, face shield, long-sleeve coveralls, safety shoes, or boots.
- Mechanical ventilation adequate enough to draw vapors, aerosol mists, or smoke away from an operator’s breathing zone should be provided at all workstations. Because CalArts does not have such workstations, at the Institute all work with foam(ed) plastics should be done outdoors.
- When adequate local exhaust ventilation is not feasible, proper personal respiratory equipment must be used.
- Monitoring for airborne contaminants may be necessary.
General Precautions for Worksite, Storage, and Disposal
- Due to potential fire hazard, consideration should be given during the design and pre- production phase to ensure appropriate egress.
- Foam(ed) plastics are combustible. Care should be taken to avoid contact with sources of ignition before, during, and after installation of all foam(ed) plastics. Smoking while working with or around foam(ed) plastics is strictly prohibited.
- Foam(ed) products and associated adhesives must be dry and cured prior to sculpting and/or shaping.
- When setting up welding / cutting operations, do not locate them in close proximity to foam(ed) plastics operations.
- Working with foam(ed) plastics produces combustible dust. Keep the work area clean.
- Fire suppression devices and materials should be readily available when working with foam(ed) plastics.
- Do not expose foam(ed) plastics to reactive chemicals (such as solvents, petroleum products, etc.). Consult the product MSDS and Manufacturer’s Technical Data Sheet for further information.
- Since uncured AB foam can generate heat and cause fires, use care in disposal.
In addition to the “General Precautions,” the following safety guidelines should be used when sculpting foam:
- Sculpting foam(ed) plastics may involve many different types of tools. Care must be taken when using sharp tools or those with moving parts to avoid injury. Be aware of others working in close proximity.
- Abrading, sawing, cutting, sanding, or other methods of sculpting foam(ed) plastics will cause dust and debris to form, which increases the potential for flammability.
- Wear appropriate PPE when necessary. Keep the work area clean by regular sweeping and disposal of dust and debris.