TM-10-3610-202-14 Table 4-1.  Organizational Preventive Maintenance Checks and Services Legend W - Weekly Q - Quarterly A-Annually H - Hours M - Monthly S - Semiannually B - Biennially MI - Miles For Readiness Interval Reporting Item Item To Be Equipment is Not No. W M Q S A B H MI Inspected Procedures Ready/Available If: 4 Shelter Door Filter Inspect for cleanliness, damage and proper installa- tion.  If necessary, clean filter as follows: Remove the filter by pulling the foam material from the frame. Clean by washing in a soap and water solution.  Dry thoroughly and spray with coater (NS:4 4130-00-860- 0042). Install filter by inserting foam material under bottom lip of frame, then tucking it under remaining three lips of frame. 5 Ladder Inspect for damage and ensure that clamps are properly attached and are not damaged.  lf inspection indicates that repair or replacement of the ladder is necessary, refer to para- graph. 6 Level Indicator Gages   Inspect the level gages for secure mounting, broken or cracked sight glass.  If inspection indicates that replacement of the level gages is necessary, refer to paragraph 4-55. Change  1       4-9/(4-10  blank)