Profile: John W Danforth Company specializes in providing HVAC solutions. We are an ISO 9001 certified company. We offer HVAC preventive maintenance & repairs, sheet metal fabrication & installation, air filtration products and services. Our HEPA filter includes stainless steel separator, double headered frame, silicone sealant, and neoprene gasket type HEPA filters. Chemical fume hoods are used to contain and exhaust chemical vapors. They are designed to protect the operator, and not for product protection.