Explosion Proof Monitors

A New Low Cost Explosion Proof Fume Hood Monitor for Hazardous Laboratories

expl-proofWe are very pleased to offer the XPA1 series of explosion proof monitors. We have models for Class 1 Div 1 & Class 1 Div 2 laboratories.

Intended for use in laboratories classified as a hazardous location, the explosion-proof low pressure alarm provides continuous monitoring of the negative static pressure in the fume hood exhaust duct. During normal negative static pressure conditions, the alarm illuminates a green indicator LED. When static pressure in the exhaust duct is insufficient, an audible alarm sounds and a red LED indicator illuminates. To maintain the integrity of the certified explosion proof instrument enclosure, the functionality of the test/reset button is performed using a light sensor.

Covering the light sensor momentarily acknowledges the alarm and silences the horn for 10 minutes. During periods of darkness, the alarm functions normally but the test/reset function is unavailable. An output relay is provided to signal a remote alarm if needed.

All electrical housings are UL or FM approved for Class 1, Div 1, Groups B, C and D.
Standard buzzer is Class 1, Div 2, optional buzzer is Class 1, Div 1.

Explosion Proof Monitors can not be purchased online, use the contact form on this page to request a quote.

Main Control Box & Cap


Pressure Switch



The style of buzzer determines the difference in safety classification.buzzer

Static Probe



  • Voltage: 120VAC
  • Frequency: 60 Hz
  • Current: 1A
  • Mains Breaker: Switch/Breaker 15A
  • Mounting: Surface Mount
  • Alarm Pressure Range: 0.07 to 0.15 inches water
  • Alarm relay output: Normally open and Normally closed volt-free contacts
  • Contacts rated 0.5A at 125 VAC / 1A at 24 VDC
  • Visual Indicators: Green LED – static pressure OK; Red LED – static pressure FAIL
  • Audible Indicator: Intermittent Buzzer – 94 dB at 10 feet
  • Horn Silence: Temporary with 10 minute self-reset, permanent until re-enabled or power-cycle
  • User Input: Alarm is silenced and tested through the use of an ambient light sensor located behind sealed window in explosion proof housing
  • Wiring method: Installer supplies explosion proof wiring materials and glands
  • Calibration: Single point pressure setting
  • Agency Listings: All housings FM or UL listed