ANSI N42.48-2018 pdf free download – American National Standard Performance Requirements for Spectroscopic Personal Radiation Detectors (SPRDs) for Homeland Security.
5.4 Effective range of measurement or indication
5.4.1 Requirement
The effective range of measurement or indication shall be specified and shall be at least 5 uR/h to100 mR/h.
When exposed to radiation fields that are greater than the effective range of measurement, the SPRD shallindicate an over-range condition.
5.4.2 Test method
Review the manual and record the stated range. The range will be confirmed during the accuracy test. Theover-range indication shall be tested during the over-range test.
5.5 Audible alarms
5.5.1 Requirements
The SPRD shall provide an audible alarm to indicate an increase in the radiation level that is greater thanthe alarm set point. Different techniques may be used to differentiate between the type of radiation detected(e.g., gamma，neutron, over-range).The frequency of an audible alarm signal shall be in the range from1000 Hz to 4000 Hz. Where an intermittent alarm signal is provided, the interval shall not exceed 2 s. TheA-weighted alarm signal volume at 30 cm from the SPRD shall be at least 80 dB(A) and shall not exceed100 dB(A).
lt shall not be possible to disable both the vibration and audible alarm indications simultaneously, exceptthrough the restricted mode.When both alarm signals are off, an indication shall be provided on the displayto inform the user of this condition.
An earphone connection (wired or wireless) should be available. When an earphone is connected, it shouldbe possible to switch off the SPRD speaker function.
5.5.2 Test method
The audible alarm signal of the SPRD shall be activated with an appropriate radiation source that may beplaced as close to the SPRD as practical.The A-weighted sound level at 30 cm shall be measured using apeak measurement device.
Verify that it is not possible to switch off the audible and vibration alarm signals simultaneously withoutaccessing the restricted mode.Verify that when both alarm modes are off, an indication is provided on thedisplay. lf a separate device is used for display, the same indication shall be provided on that device.
lf an earphone connection is provided, verify that the earphone functions when connected and that theSPRD speaker can be switched off.
5.6 Vibration alarm
5.6.1 Requirements
The SPRD shall have a vibration alarm signal capability. The vibration alarm shall have sufficient intensityto inform the user of an alarm condition.
The use of carrying pouches is discouraged. lf a holder is used, there should be a rigid connection betweenthe holder and the SPRD such that there is no loss of vibration intensity to the user.
The intensity of the vibration at the surface of the SPRD(pouch or holder, when used) shall be greater than0.8 g.The vibration motor used by the SPRD should rotate between 9 000 rpm and 11 000 rpm.
5.6.2 Test method
Review the manual and record the vibratory motor rotation frequency stated by the manufacturer.Install new batteries or fully charge the batteries, as applicable, in the SPRD being tested.
Attach the SPRD (in a pouch or attached to a holder, when appropriate) to a flat, hard surface using non-cushioning double-sided tape if possible. Attach a single-axis accelerometer to the side of the SPRD that,when worn, is closest to the wearer.
After allowing the vibration measurement system to settle,activate the alarm signal and once themeasurement is stable, record the results. The measured intensity shall be greater than 0.8 g.After a periodof 10 s, reduce the radiation field and allow the SPRD to return to normal operation(non-alarm condition).Repeat the test two additional times.Each measured reading shall be greater than 0.8 g to be acceptable.lf the vibration signal is intermittent, measure the intensity during the activated period.
5.7.1 Requirements
The overall dimensions of the SPRD should be like that of a personal radiation detector (within therectangular solid defined by 20 cm in length,10 cm in width, and 5 cm in depth).
Means shall be provided to securely fix the SPRD to the user (e.g.. a clip, ring, or lanyard), with attentiongiven to the necessary orientation of the detector and display.
5.7.2 Test method
Measure the physical dimensions of the SPRD. The SPRD shall be measured outside of its holster orcarrying case and the measurement shall exclude the clip and/or lanyard.ANSI N42.48 pdf download.