# API 607 vs API 608: Key Differences in Valve Fire Testing Standards

Introduction

When it comes to fire safety in industrial valves, two key standards often come into play: API 607 and API 608. Both are developed by the American Petroleum Institute (API) but serve different purposes in valve fire testing. Understanding the differences between these standards is crucial for engineers, procurement specialists, and safety professionals working with valves in fire-prone environments.

What is API 607?

API 607 is the standard for Fire Test for Quarter-Turn Valves and Valves Equipped with Nonmetallic Seats. This standard specifies fire testing requirements for:

• Quarter-turn valves (such as ball, butterfly, and plug valves)
• Valves with nonmetallic seating materials
• Valves intended for flammable service

The test evaluates a valve’s ability to maintain pressure integrity during and after exposure to fire conditions.

What is API 608?

API 608 is titled Metal Ball Valves – Flanged, Threaded, and Welding End. While it includes some fire testing requirements, its primary focus is on:

• Design and manufacturing of metal ball valves
• Pressure-temperature ratings
• Materials and dimensions
• Testing and inspection requirements

Key Differences Between API 607 and API 608

1. Scope and Application

API 607 is specifically focused on fire testing methodology and performance requirements, while API 608 is a comprehensive standard covering the entire design and manufacturing process of metal ball valves.

2. Valve Types Covered

API 607 applies to various quarter-turn valves with nonmetallic seats, whereas API 608 is exclusively for metal ball valves.

3. Fire Testing Requirements

API 607 provides detailed fire testing procedures that are more rigorous than the fire testing mentioned in API 608. The API 607 test includes:

• 30-minute fire exposure at 1400-1800°F (760-980°C)
• External and internal leakage measurements
• Operability testing during and after fire exposure

4. Certification Process

API 607 requires third-party certification of fire test performance, while API 608 allows manufacturer self-certification for most requirements.

When to Use Each Standard

Choose API 607 when:

• You need valves with verified fire-safe performance
• Working with quarter-turn valves having nonmetallic seats
• Operating in high-risk fire environments

Choose API 608 when:

• Specifying metal ball valves for general service
• Need comprehensive design and manufacturing standards
• Fire safety is important but not the primary concern

Conclusion

While both API 607 and API 608 address valve performance, they serve distinct purposes. API 607 is the gold standard for fire testing of quarter-turn valves, while API 608 provides comprehensive specifications for metal ball valves. Understanding these differences ensures proper valve selection for your specific application requirements, particularly in environments where fire safety is a critical