ASSE 1060

In 1996, the American Society of Sanitary Engineering released a new standard to regulate the budding backflow enclosure industry: ASSE 1060. Enclosures built before 1996 may have had too little or too much insulation, or heaters that weren't safe. Sometimes they were simply a fiberglass box placed on top of valves.

Before 1060 was released, drainage was as much a problem with enclosures as it is today for RPZ backflow preventers installed indoors. It's especially interesting that Plumbing Standards Magazine was publishing information on RPZ discharge rates and the dangers of confined spaces in 1996, and these are the same problems we're facing today.

The standard has since been updated: once in 2006, adding more detail to the testing. It also clarified that equipment enclosures designed for "fluid conveying components" need to pass this threshold, not just "backflow preventer enclosures." It was updated again in 2017, changing the requirements for heaters and adding testing requirements.

ASSE recommends these enclosures are installed in a way that conforms to local codes, most of which require covers to be ASSE certified. Products can only be ASSE approved if the manufacturer has applied to ASSE and had their product tested in ASSE's lab. The process can take up to 60 days and, in 1996, it could cost up to $25,000.

Once the product has passed the test, as Safe-T-Cover's have, they earn a seal of approval. Here's what that approval means.

The primary specifications of the ASSE 1060 standard include:

1.0 Classifications

Class I Freeze Protection Enclosures Heated

Enclosures designed and constructed to maintain a minimum internal temperature of 40°F with an external temperature of -30°F with a minimum thermal resistance (R) value of eight (8.0). Heat sources and related equipment supplied by the enclosure manufacturers shall be listed for use in damp or wet locations by an independent third-party certification agency and shall be constructed and installed so that water or other liquids cannot enter or accumulate in or on wired sections, electrical components or duct work. Heater shall be installed as specified by the manufacturer’s installation instructions and local codes.

Class II Freeze Retardant Enclosures 

Freeze retardant enclosures shall have a minimum thermal resistance (R) value of eight (8.0). These enclosures shall be designed and constructed to be installed in climates where the ambient temperature does not go below 33.0 °F for long periods of time. These enclosures offer no guarantee of freeze protection and are for indeterminable temporary freeze protection when the ambient temperature drops below freezing for a short period of time.

Class III Non-Freeze Protection Enclosures

Enclosures designed and constructed without freeze protection and have no minimum thermal resistance (R) value.

2.0 Structural Strength

All classification enclosures must be designed to support a minimum vertical load of 100 pounds per square foot (100 psf). See our infographic for reference.

3.0 Drainage Capability

All classification enclosures must be designed to discharge water from within the enclosure to prevent equipment submersion. The depth of water rise within the enclosure shall not exceed eight inches during full discharge of a reduced pressure zone (RPZ) backflow preventer and in accordance with the following diameter requirements:

4.0 Access for Testing and Maintenance

Equipment components, such as test cocks and valve handles or hand wheels, must be within 24 inches of the access opening.

Hinged access panels must be restrained in the open and closed position.

All unrestrained panels and horizontal hinged panels can weigh no more than 70 pounds.

5.0 Security and Vandalism

Access to the internal equipment shall be lockable. Access shall be by keyed devices or have the ability to affix padlocks.

6.0 Materials of Construction

Exposed Exterior Wall Panel Materials

• Aluminum
• Galvannealed Steel
• Prepainted Galvanized Steel
• Stainless Steel
• Natural Stone
• Fiberglass-Reinforced Plastic & Gelcoat (25% glass fiber by weight with 18-20 mil gelcoat on outer surface)
  
  

Exposed Internal Wall Panel Materials

• Cedar
• Redwood
• Closed Cell Foam Insulation (1% maximum water absorption)
• Glass Fiber-Reinforced Facers
• Approved External Materials